C166S V2 Core User's Manual

Use r Ma nual, V 1.7, Ja nuary 2001
C166S V2
1 6 - B i t M ic r o c o n t r o l l e r
M i c r o c o n t ro l le r s
N e v e r
s t o p
t h i n k i n g .
Edition 2001-01
Published by Infineon Technologies AG,
St.-Martin-Strasse 53,
D-81541 München, Germany
© Infineon Technologies AG 2001.
All Rights Reserved.
Attention please!
The information herein is given to describe certain components and shall not be considered as warranted
characteristics.
Terms of delivery and rights to technical change reserved.
We hereby disclaim any and all warranties, including but not limited to warranties of non-infringement, regarding
circuits, descriptions and charts stated herein.
Infineon Technologies is an approved CECC manufacturer.
Information
For further information on technology, delivery terms and conditions and prices please contact your nearest
Infineon Technologies Office in Germany or our Infineon Technologies Representatives worldwide (see address
list).
Warnings
Due to technical requirements components may contain dangerous substances. For information on the types in
question please contact your nearest Infineon Technologies Office.
Infineon Technologies Components may only be used in life-support devices or systems with the express written
approval of Infineon Technologies, if a failure of such components can reasonably be expected to cause the failure
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devices or systems are intended to be implanted in the human body, or to support and/or maintain and sustain
and/or protect human life. If they fail, it is reasonable to assume that the health of the user or other persons may
be endangered.
Use r Ma nual, V 1.7, Ja nuary 2001
C 1 6 6 S V2
1 6 - B it M icr o c ontroller
M i c r o c o n t ro l le r s
N e v e r
s t o p
t h i n k i n g .
C166S V2
Revision History:
2001-01
Previous Version:
-
Page
V 1.7
Subjects (major changes since last revision)
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User Manual
C166S V2
Table of Contents
Page
1
1.1
1.2
1.2.1
1.2.2
1.2.3
1.2.4
1.2.5
1.2.6
1.2.7
1.2.8
1.2.9
1.2.10
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Technical Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
System Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
CPU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
On-Chip Memory Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Data Management Unit (DMU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Program Memory Unit (PMU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Interrupt and PEC Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
OCDS and JTAG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
External Bus Controller (EBC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
System Control Unit (SCU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Clock Generation Unit (CGU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
On-Chip Bootstrap Loader . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
2
2.1
2.2
2.3
2.3.1
2.3.2
2.3.3
2.3.3.1
2.3.3.2
2.3.4
2.3.5
2.3.6
2.3.6.1
2.3.6.2
2.4
2.4.1
2.4.2
2.4.3
2.4.3.1
2.4.3.2
2.5
2.5.1
2.5.2
2.5.2.1
2.5.2.2
2.5.2.3
2.5.2.4
2.5.3
2.5.4
Central Processing Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Register Description Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CPU Special Function Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Instruction Fetch and Program Flow Control . . . . . . . . . . . . . . . . . . . . . . .
Branch Target Addressing Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Branch Detection and Branch Prediction . . . . . . . . . . . . . . . . . . . . . . . .
Sequential and Mispredicted Instruction Flow . . . . . . . . . . . . . . . . . . . .
Correctly Predicted Instruction Flow . . . . . . . . . . . . . . . . . . . . . . . . .
Incorrectly Predicted Instruction Flow . . . . . . . . . . . . . . . . . . . . . . . .
Atomic and Extend Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Code Addressing via Code Segment and Instruction Pointer . . . . . . . .
IFU Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The CPU Configuration Register CPUCON1 . . . . . . . . . . . . . . . . . . .
The CPU Configuration Register CPUCON2 . . . . . . . . . . . . . . . . . . .
Use of General Purpose Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Memory Mapped GPR Banks and the Global Register Bank . . . . . . . .
Local Register Bank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Context Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Changing the selected Physical Register Bank . . . . . . . . . . . . . . . . .
Context Switching of the Global Register Bank . . . . . . . . . . . . . . . . .
Data Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Short Addressing Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Long and Indirect Addressing Modes . . . . . . . . . . . . . . . . . . . . . . . . . .
Addressing via Data Page Pointer DPP . . . . . . . . . . . . . . . . . . . . . .
DPP Override Mechanism in the C166S V2 CPU . . . . . . . . . . . . . . .
Long Addressing Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Indirect Addressing Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DSP Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The CoREG Addressing Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
User Manual
5
15
17
18
19
20
22
24
24
26
27
28
30
30
31
34
36
40
40
40
42
45
46
48
49
51
52
53
56
63
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C166S V2
Table of Contents
Page
2.5.5
2.6
2.6.1
2.6.2
2.6.3
2.6.4
2.6.5
2.6.6
2.7
2.7.1
2.7.2
2.7.3
2.7.4
2.7.5
2.7.6
2.7.7
2.7.8
2.7.9
2.7.10
2.7.11
2.8
The System Stack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Data Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Data Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Constants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
16-bit Adder/Subtracter, Barrel Shifter, and 16-bit Logic Unit . . . . . . . .
Bit Manipulation Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Multiply and Divide Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The Processor Status Word PSW . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parallel Data Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Representation of Numbers and Rounding . . . . . . . . . . . . . . . . . . . . . .
The 16-bit by 16-bit signed/unsigned Multiplier and Scaler . . . . . . . . . .
Concatenation Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
One-bit Scaler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The 40-bit Adder/Subtracter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The Data Limiter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The Accumulator Shifter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The 40-bit Signed Accumulator Register . . . . . . . . . . . . . . . . . . . . . . . .
The Repeat Counter MRW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The MAC Unit Status Word MSW . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The MAC Unit Control Word MCW . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dedicated CSFRs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3
3.1
3.2
3.3
3.3.1
3.3.2
3.3.3
3.3.4
3.4
3.4.1
3.5
3.6
3.6.1
C166S V2 Memory Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Data Organization in Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Internal Program Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
DPRAM, Internal SRAM, and SFR Areas . . . . . . . . . . . . . . . . . . . . . . . . . 94
Data Memories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Special Function Register Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
IO Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
PEC Source and Destination Pointers . . . . . . . . . . . . . . . . . . . . . . . . . . 97
External Memory Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Boot and Debug/Monitor Program Memories . . . . . . . . . . . . . . . . . . . . 98
Crossing Memory Boundaries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
System Stack . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Data Organization in Global General Purpose Registers . . . . . . . . . . 100
4
4.1
4.1.1
4.1.2
4.1.3
4.1.4
Instruction Pipeline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Instruction Dependencies in Different Pipeline Stages . . . . . . . . . . . . . .
The General Purpose Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Indirect Addressing Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Memory Bandwidth Conflicts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CPU-SFRs and the Pipeline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5
Interrupt and Exception Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
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6
64
68
68
70
70
70
71
74
78
79
80
80
80
81
81
82
82
84
85
88
89
103
104
104
106
107
110
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C166S V2
5.1
5.1.1
5.1.2
5.1.3
5.1.4
5.1.5
5.2
5.2.1
5.2.2
5.2.3
5.2.4
5.3
5.3.1
5.3.2
5.4
5.4.1
5.4.2
5.4.3
5.4.4
5.5
Interrupt System and Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Interrupt System Structure . . . . . . . . . . . . . . . . . . . . . . . . . . .
Interrupt Arbitration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Interrupt Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Interrupt Vector Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Interrupt Jump Table Cache . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Status and Switch Context Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Interrupt Control Functions in the PSW . . . . . . . . . . . . . . . . . . . . . . . .
Saving the Status during Interrupt Service . . . . . . . . . . . . . . . . . . . . .
Context Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fast Bank Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Traps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Software Traps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hardware Traps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Peripheral Event Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PEC Control Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The PEC Source and Destination Pointer . . . . . . . . . . . . . . . . . . . . . .
PEC Handler Interrupt Actions Summary . . . . . . . . . . . . . . . . . . . . . .
PEC Channel Assignment and Arbitration . . . . . . . . . . . . . . . . . . . . . .
CPU Action Control Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
118
118
120
122
124
125
127
127
129
130
131
132
132
133
138
139
145
147
149
151
6
6.1
6.2
6.2.1
6.2.2
6.2.3
6.2.4
6.2.5
6.2.6
6.3
6.3.1
6.3.2
6.3.3
6.3.4
6.3.5
6.3.5.1
6.3.5.2
6.3.6
6.3.6.1
6.3.6.2
6.3.6.3
6.3.7
External Bus Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Timing Principles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
E Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
F Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Configuration Register Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The EBC MODE Registers EBCMODx . . . . . . . . . . . . . . . . . . . . . . . .
The Timing Configuration registers TCONCSx . . . . . . . . . . . . . . . . . .
The Function Configuration Registers FCONCSx . . . . . . . . . . . . . . . .
The Address Window Selection Registers ADDRSELx . . . . . . . . . . . .
Definition of Address Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Address Window Arbitration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ready Controlled Bus Cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The Synchronous/Asynchronous READY . . . . . . . . . . . . . . . . . . . .
Combining the READY function with predefined wait states . . . . . .
EBC Idle State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
153
153
154
157
157
157
157
157
158
158
158
158
161
163
164
164
166
167
167
168
168
169
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6.4
6.4.1
6.4.1.1
6.4.1.2
6.4.1.3
6.4.1.4
6.4.2
6.5
Multi Master Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
External Bus Arbitration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Initialization of Arbitration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Arbitration Master Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Arbitration Slave Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Locking the Bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Connecting Multimaster Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fastest possible external access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
169
169
169
170
171
171
172
173
7
7.1
7.2
7.3
Instruction Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Short Instruction Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Instruction Set Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Instruction Opcodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
175
175
178
192
8
8.1
8.2
8.3
Detailed Instruction Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Normal Instruction Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DSP Instruction Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Instructions for OCDS/ITC injection and System Control . . . . . . . . . . . .
205
212
315
417
9
9.1
9.2
9.2.1
9.2.2
9.3
9.3.1
9.3.2
9.4
9.4.1
9.4.2
Summary of CPU/Subsystem Registers . . . . . . . . . . . . . . . . . . . . . . .
General Purpose Registers (GPRs) . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Core Special Function Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ordered by Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ordered by Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Register Overview Interrupt and Peripheral Event Controller . . . . . . . . .
Ordered by Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ordered by Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Register Overview External Bus Controller . . . . . . . . . . . . . . . . . . . . . . .
Ordered by Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ordered by Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
421
421
423
423
424
426
426
427
430
430
431
10
Keyword Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 433
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Introduction
1
Introduction
C166S V2 is a member of the most recent generation of the popular C166
microcontroller cores. C166S V2 combines high performance with enhanced modular
architecture. It was developed to provide easy migration from standard existing C16x to
the new C166S V2 core with its impressive DSP performance and advanced interrupt
handling. The system architecture inherits successful hardware and software concepts
that have been established in the C16x 16-bit microcontroller families. C166 code
compatibility enable re-use of existing code. This dramatically reduces the time-tomarket for new product development.
The following features position C166S V2 strategically for contemporary and emerging
markets for performance-hungry real-time applications:
– High CPU performance. Single clock cycle execution doubles the performance at the
same CPU frequency (relative to the performance of the C166).
– Built-in advanced MAC unit dramatically increases DSP performance.
– High Internal Program Memory bandwidth and the instruction fetch pipeline
significantly improve program flow regularity and optimize fetches into the execution
pipeline.
– Sophisticated Data Memory structure and multiple high-speed data buses provide
transparent data access (0 cycles) and broad bandwidth for efficient DSP processing.
– Advanced exceptions handling block with multi-stage arbitration capability yields
stellar interrupt performance with extremely small latency.
– Upgraded Peripheral Event Controller supports efficient and flexible DMA features to
support a broad range of fast peripherals.
– Highly modular architecture and flexible bus structure provide effective methods of
integrating application-specific peripherals to produce customer-oriented derivatives.
This User’s Manual describes the new standard C166S V2 core independently from its
use for the dedicated product. Differencies to existing standard products are therefore
described in the User’s Manual (or Target Specification) of the product.
1.1
–
–
–
–
–
–
–
–
–
–
Technical Overview
5-stage execution pipeline
2-stage instruction fetch pipeline with FIFO for instruction pre-fetching
Pipeline with forwarding that controls data dependencies in hardware
Linear address space for code and data (von Neumann architecture)
Multiple high bandwidth internal busses for data and instructions
Enhanced memory map with extended I/O areas
16 MBytes total linear address space
C16x family compatible on-chip special function register area
Fast multiplication (16-bit x 16-bit) in one CPU clock cycle
Fast background execution of division (32-bit/16-bit) in 21 CPU clock cycles
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Introduction
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
Nearly all instructions executed in one CPU clock cycle
Enhanced boolean bit manipulation facilities
Zero cycle jump execution
Additional instructions to support High Level Language (HLL) and operating systems
Register-based design with multiple variable register banks
Two additional fast register banks
General purpose register architecture
16 General-purpose registers (GPRs) for byte operands
16 General-purpose registers (GPRs) for integer operands
Overlapping 8-bit and 16-bit registers
Opcode fully upward compatible with C166 family
Variable stack with automatic stack overflow/underflow detection
High performance branch-, call- and loop processing
Multiply and accumulate instructions (MAC) executed in one CPU clock cycle
Extremely short interrupt response time
"Fast interrupt" and "Fast context switch" features
Peripheral bus (PDBUS+) with bit protection
1.2
System Description
The basic C166S V2 System consists of the following main units:
•
•
•
•
•
•
•
•
•
C166S V2 CPU
On-Chip Data- and Code-Memories
Data Management Unit (DMU)
Program Management Unit (PMU)
Interrupt and Peripheral Event Controller (PEC) Controller
OCDS and JTAG-Interface
External Bus Controller (EBC)
System Control Unit (SCU)
Clock Generation Unit (CGU)
The powerful C166S V2 core, the peripherals, and the internal memories of the
C166S V2 microcontroller are connected to various busses:
•
•
•
•
16-bit high performance system bus
16-bit enhanced peripheral bus (PDBUS+)
64-bit internal program memory bus
16-bit data memory bus
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Introduction
Figure 1-1 shows a typical configuration of a C166S V2-based system.
C166S V2 MegaCore
16
Data Memory
PMU
up tp 3 kBytes
DPRAM
C166S V2 CPU
64
up tp 24 kBytes
SRAM
64
Program Memory
DMU
up to 4MBytes
Break
Interface
Injection
Interface
Trace
Interface
WDT
Interrupt Controller
and
Peripheral Event Controller
C166S V2
System
SCU
CGU
OSC
16
High Speed System Bus
16
EBC
OCDS
Peripheral
n
Figure 1-1
1.2.1
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
JTAG
External Bus Interface
Bus
JTAG
RESET
CONFIG
XTAL2
Dedicated Pins
XTAL1
PORT
CLKOUT
PORT
Peripheral
....
NMI
PORT
Periheral
2
CLKOUT
Peripheral
1
Config.
Block
External
PDBUS+
PLL
C166S V2 System
CPU
5-stage execution pipeline
2-stage instruction fetch pipeline with FIFO for instruction pre-fetching
Pipeline with forwarding that controls data dependencies in hardware
Flexible PMU and DMU with cache capabilities
Linear address space for code and data (von Neumann architecture)
Multiple high bandwidth internal busses for data and instructions
16 MBytes total linear address space
Nearly all instructions executed in one CPU clock cycle
Enhanced boolean bit manipulation facilities
Zero cycle jump execution
Additional instructions to support HLL and operating systems
Register-based design with multiple variable register banks
Two additional fast register banks
General purpose register architecture
16 General-purpose registers (GPRs) for byte operands
16 General-purpose registers (GPRs) for integer operands
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Introduction
– Overlapping 8-bit and 16-bit registers
Multiply Accumulate Unit (MAC)
– Single cycle MAC with zero cycle latency including a 16*16 multiplier plus 40-bit barrel
shifter; single clock multiplication is ten times faster than C166 at the same CPU clock
– 40-bit accumulator to handle overflows
– Automatic saturation to 32 bit or rounding included with the MAC instruction
– Fractional numbers supported directly
– One Finite Impulse Response Filter (FIR) tap per cycle with no circular buffer
management
1.2.2
–
–
–
On-Chip Memory Modules
Up to 3 KBytes on-chip dual ported SRAM for DSP data and register banks
Up to 24 KBytes on-chip internal single ported SRAM module for data storage
Up to 4 MBytes on-chip memory module for program storage
Note: The on-chip memory configuration may differ from product to product. Product
specific on-chip memory configurations are defined in the corresponding product
specifications.
1.2.3
Data Management Unit (DMU)
The Data Management Unit (DMU) handles all data transfers external to the core (i.e.
external memory or on-chip special function registers on the PDBUS+) and instruction
fetches in external memory. The DMU acts as a data mover between the various
interfaces. By handling all these interfaces, it incorporates the C166S V2 System Bus.
An access prioritization between External BUS Controller (EBC) accesses from the core
and Program Memory Unit (PMU) is handled by the DMU. This allows an instruction
fetch from external memory in parallel with data access that is not on EBC.
1.2.4
Program Memory Unit (PMU)
The PMU has two basic functions: to provide the CPU with instructions and to provide
the CPU (through the DMU) with data located in the Internal Program Memory. The
Internal Program Memory is implemented within the PMU.
The instructions requested by the CPU can be located in the Internal Program Memory;
in which case, the instructions are requested to the internal memory. Alternatively, they
can be located in external memory; in which case, the PMU re-sends this request to the
EBC through the DMU, receives the data from the external memory, through the EBC/
DMU, and delivers it as the requested instruction to the CPU.
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1.2.5
Interrupt and PEC Controller
– 16-Priority-level interrupt system with up to 128 sources on four group levels
– Eight PEC channels with 24-bit source and destination pointers with segment pointer
registers
– Enhanced PEC pointers. PEC source pointers and PEC destination pointers can be
simultaneously modified
– Independent programmable PEC level and "End of PEC" interrupt
1.2.6
OCDS and JTAG
The OCDS (level 1) provides facilities to the debugger to emulate resources and assist
in application program debug. The main features are:
– Real time emulation
– Extended trigger capability including: instruction pointer events, data events on
address and/or value, external inputs, counters, chaining of events, timers, etc.
– Software break support
– Break and “break before make” (on IP events only)
– Interrupt servicing during break or monitor mode
– Simple monitor mode or JTAG based debugging through instruction injection
The C166S V2 OCDS is controlled by the debugger1) through a set of registers
accessible from the JTAG interface. The OCDS also receives informations (such as IP,
data, status) from the core for monitoring the activity and generating triggers. Finally, the
OCDS interacts with the core through a break interface to suspend program execution,
and through an injection interface to allow execution of OCDS generated instructions.
1.2.7
External Bus Controller (EBC)
All external memory accesses are performed by a particular on-chip External Bus
Controller (EBC).
1.2.8
System Control Unit (SCU)
The System Control Unit supports all central control tasks and all product specific
features. The following typical sub-modules are implemented in this unit:
Reset Control
The reset function is controlled by the reset control unit.
1)
Debugger refers to the tool connected to the emulator, and more specifically to the OCDS via the JTAG and
which manages the emulation/debugging task.
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Introduction
Power Saving Control
The Power Saving Control block, known from the power management of the C166
derivatives, manages idle mode, power down mode, and sleep mode of the C166S V2.
ID Control
A set of six identification registers is defined for the most important silicon parameters,
including the chip manufacturer, the chip type and its properties. These ID registers can
be used for automatic test selection.
External Interrupt Control
The C166S V2 System provides asynchronous fast external interrupt inputs.
Central System Control
The central system behavior of the C166S V2 is controlled by this block. The frequency
of the PDBUS+ (bus clock) and of all peripherals connected to this bus is programmable
according to the maximum physical bus speed and the application requirements.
Furthermore, the clock generation status is indicated. Depending on the application
state, various security levels (such as protected and unprotected mode) are supported
by the security level control state machine.
Watchdog Timer (WDT)
The Watchdog Timer is one of the fail-safe mechanisms that have been implemented to
prevent the controller from malfunctioning. However, the Watchdog Timer can detect
only long term malfunctions.
1.2.9
Clock Generation Unit (CGU)
The C166S V2 Clock Generation Unit uses either an oscillator or crystal to generate the
system clock. A programmable on-chip PLL adds high flexibility to clock generation for
the C166S V2.
1.2.10
On-Chip Bootstrap Loader
As in the C166, the on-chip bootstrap loader allows the start code to be moved into
internal RAM via the serial interface.
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Central Processing Unit
2
Central Processing Unit
C166S V2 CPU represents the third generation of the well known C166 core family. It
combines many powerful enhancements with compatibility to the C166 family. The new
architecture results in high CPU performance, fast and efficient access to different kinds
of memories, and proficient peripheral units integration.
.
System-Bus
data out
address
PMU
data in
Internal Program Memory
CPU
Prefetch Unit
Branch Unit
DPRAM
CSP
IP
CPUCON1
CPUCON2
CPUID
FIFO
Return Stack
IDX0
IDX1
QX0
QX1
QR0
QR1
+/-
+/-
Multiply Unit
MRW
VECSEG
TFR
5-Stage
Pipeline
Injection/Exception
Handler
IFU
DPP0
DPP1
DPP2
DPP3
+/MAH
MAL
R15
R15
R14 R15
R14
R14
GPRs
GPRs
GPRs
PSW
+/-
MDH
ZEROS
MDL
ONES
R15
R14
GPRs
R1
R1
R0 R1
R0
R0
Barrel-Shifter
MDC
R1
R0
RF
data in
Buffer
ALU
WB
data out
data in
address
data out
address
data out
data in
User Manual
address
Division Unit Bit-Mask-Gen.
DMU
Peripheral-Bus
Figure 2-1
CP
ADU
MAC
SRAM
IPIP
SPSEG
SP
STKOV
STKUN
Multiply Unit
MCW
MSW
2-Stage
Prefetch
Pipeline
System-Bus
CPU Architecture
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Central Processing Unit
The new core architecture of the C166S V2 CPU results in higher CPU clock frequencies
and reduces the number of clock cycles per executed instruction by half, compared to
the C166 core. C166S V2 CPU also integrates a multiplication and accumulation unit
which dramatically increases performance of the DSP-intensive tasks.
C166S V2 CPU has eight main units that are listed below. All of these units have been
optimized to achieve maximum performance and flexibility.
• High Performance Instruction Fetch Unit (IFU)
– High Bandwidth Fetch Interface
– Instruction FIFO
– High Performance Branch-, Call-, and Loop-Processing with instruction flow
prediction
• Return Stack
– Injection/Exception Handler
– Handling of Interrupt Requests
– Handling of Hardware Failures
• Instruction Pipeline (IPIP)
– Bypassable 2-stage Prefetch Pipeline
– 5-stage Execution Pipeline
• Address and Data Unit (ADU)
– 16-bit arithmetic unit for address generation
– DSP address unit with a set of dedicated address- and offset pointers
• Arithmetic and Logic Unit (ALU)
– 8-bit and 16-bit Arithmetic Unit
– 16-bit Barrel Shifter
– Multiplication and Division Unit
– 8-bit and 16-bit Logic Unit
– Bit manipulation Unit
• Multiply and ACcumulate Unit (MAC)
– 16-bit multiplier with 32-bit result generation1)
– 40-bit Accumulator with 40-bit Barrel Shifter
– Repeat Control Unit
• Register File (RF)
– 5-port Register File with three independent register banks
• Write Back Buffer (WB)
– 3-entries buffer
1)
The same hardware-multiplier is used in the ALU and in the MAC Unit.
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Central Processing Unit
2.1
Register Description Format
C166S V2 CPU contains a set of Special Function Register (SFR) and Extended Special
Function Registers (ESFR). They are described in the respective chapter of this manual.
The example below shows how to interpret the format and notation used to describe
SFRs and ESFRs.
A word register looks like this:
REG_NAME
Short Description
SFR(b)/ESFR(b)/XSFR
15
14
13
12
11
10
0
0
0
0
0
0
r
r
r
r
r
r
9
8
7
6
Reset Value: aaaaH
5
4
3
2
1
0
bitfield
A
0
0
bit
C
bit
B
bit
A
rwh
r
r
rw
rw
rwh
A byte register looks like this:
REG_NAME
Short Description
7
SFR(b)/ESFR(b)/XSFR
6
5
4
Reset Value: aaH
3
2
1
0
0
bitfield
A
0
bit
C
bit
B
bit
A
r
rwh
r
rw
rw
rwh
Field
Bits
Type Description
bitfieldX
[m:n]
type
Description
value Function off(Default)
value Enable Function 1
...
...
bitX
[n]
type
Description
0
Function off(Default)
1
Enable Function
Elements:
REG_NAME
bitX
bitfieldX
A16 / A8
SFR(b)/ESFR(b)
XSFR
User Manual
Name of this register
Name of bit
Name of bitfield
Long 16-bit address/Short 8-bit address
Register space (SFR or ESFR (bit addressable) Register)
Register located in the internal 4 k IO area
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(* *) * *
Register contents after reset
’0/1’
: defined value,
’U’
: unchanged (undefined (’X’) after power up)
’?’
: defined by reset configuration
[n]
[m:n]
Bit number
n
: Bit number first bit of the bitfield
m
: Bit number of last bit of the bitfield
type
’r’
’w’
’h’
: readable by software
: writable by software
: writable by hardware
value
’0/1’
’X’
’0’
: defined value,
: undefined,
: reserved for future purpose, read access delivers 0,
must not be set to 1
2.2
CPU Special Function Registers
The core CPU requires a set of CPU Special Function Registers (CSFRs) to maintain
the system state information, to control system and bus configuration, and to manage
code memory segmentation and data memory paging. The CPU also uses CSFRs to
access the General Purpose Registers (GPRs) and the System Stack, to supply the ALU
with register-addressable constants, and to support multiply and divide ALU operations.
The access mechanism for these CSFRs in the CPU core is identical to the access
mechanism for any other SFR. Since all SFRs can be controlled by any instruction
capable of addressing the SFR/CSFR memory space, there is no need for special
system control instructions.
However, to ensure proper processor operations, certain restrictions on the user access
to some CSFRs must be imposed. For example, the Instruction Pointer (IP) and Code
Segment Pointer (CSP) cannot be accessed directly at all. They can only be changed
indirectly via branch instructions.
The PSW, SP, and MDC registers can be modified not only explicitly by the programmer,
but also implicitly by the CPU during normal instruction processing.
Note: Note that any explicit write request (via software) to an CSFR supersedes a
simultaneous modification by hardware of the same register.
Note: All SFRs may be accessed wordwise, or bytewise (some of them even bitwise).
Reading bytes from word SFRs is a non-critical operation. Any write operation to
a single byte of an CSFR clears the non-addressed complementary byte within the
specified CSFR.
Non-implemented (reserved) CSFR bits cannot be modified, and will always
supply a read value of 0.
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2.3
Instruction Fetch and Program Flow Control
64bit
data
24-bit address
The Instruction Fetch Unit (IFU) pre-fetches and pre-processes instructions to provide a
continuous instruction flow. The IFU can fetch simultaneously at least two instructions
via a 64-bit wide bus from the Program Management Unit (PMU). The pre-fetched
instructions are stored in an instruction FIFO. Pre-processing of branch instructions
enables the instruction flow to be predicted. While the CPU is in the process of executing
an instruction fetched from the FIFO, the pre-fetcher of the IFU starts to fetch a new
instruction at a predicted target address from the PMU. The latency time of this access
is hidden by the execution of the instructions which have been buffered in the FIFO
before. Even for a non-sequential instruction, execution the IFU can generally provide a
continuous instruction flow. The IFU contains two pipeline stages: the Prefetch Stage
and the Fetch Stage.
IFU Control
IFU Pipeline
Instruction Buffer(up to 6 Instr.)
+/-
Prefetch
Stage
CSP
IP
Branch Detection and Prediction Logic
Return Stack
Instruction Buffer(up to 3 Instr.)
Control Registers
Instruction
FIFO
Injection and Exception Handler
VECSEG
TFR
Bypass Fetch to Decode
CPUID
Fetch
Stage
Branch Folding
Unit
CPUCON2
Bypass Prefetch to Decode
CPUCON1
Decode
Stage
Instruction Buffer(up to 1 Instr.)
Figure 2-2
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During the pre-fetch stage, the Branch Detection and Prediction Logic analyzes up to
three pre-fetched instructions stored in the first Instruction Buffer (up to six instructions).
If a branch is detected, then the IFU starts to fetch the next instructions from the PMU
according to the prediction rules. After having been analyzed, up to three instructions are
stored in the second Instruction Buffer (three instructions) which is the input register of
the Fetch Stage.
On the Fetch Stage, the pre-fetched instructions are stored in the instruction FIFO. The
Branch Folding Unit (BFU) allows processing of branch instructions in parallel with
preceding instructions. To achieve this the BFU pre-processes and re-formats the
branch instruction. First, BFU defines (calculates) the absolute target address. This
address—after being combined with branch condition and branch attribute bits—is
stored in the same FIFO step as the preceding instruction. The target address is also
used to pre-fetch the next instructions.
For the Execution Pipeline, both instructions are fetched from the FIFO again and are
executed in parallel. If the instruction flow was predicted incorrectly (or FIFO is empty),
the two stages of the IFU can be bypassed.
Note: Pipeline behavior in case of a incorrectly predicted instruction flow is described in
the following sections.
2.3.1
Branch Target Addressing Modes
The target address and the segment of jump or call instructions can be specified by
several addressing modes. The Instruction Pointer register (IP) may be updated using
relative, absolute, or indirect modes. The Code Segment Pointer register (CSP) can be
updated using an absolute value only. A special mode is provided to address the
interrupt and trap jump vector table which resides in the lowest portion of the code
segment selected by the VECSEG register contents.
Table 2-1
Branch Target Addressing Modes
Mnemonic Target Address
Target Segment
Valid Address Range
caddr
(IP)
= caddr
-
caddr = 0000H...FFFEH
rel
(IP)
(IP)
= (IP) + 2*rel
= (IP) + 2*(rel+1)
-
rel
rel
[Rw]
(IP)
= (Rw)
-
Rw w = 0...15
seg
-
(CSP) = seg
seg
#trap7
(IP)
(CSP) = VECSEG
trap7 = 00H...7FH
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= 0000H +
VECSC*trap7
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= 80H...FFH
= 0...255(3)
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caddr:
Specifies an absolute 16-bit code address within the current segment.
Branches MAY NOT be taken to odd code addresses. Therefore, the least
significant bit of ’caddr’ is not used.
rel:
This mnemonic represents an 8-bit signed word offset address relative to the
current Instruction Pointer contents, which points to the instruction after the
branch instruction. Depending on the offset address range, both forward (’rel’=
00H to 7FH) and backward (’rel’= 80H to FFH) branches are possible. The
branch instruction itself is repeatedly executed, when ’rel’ = ’-1’ (FFH) for a
word-sized branch instruction, or ’rel’ = ’-2’ (FEH) for a double-word-sized
branch instruction.
[Rw]:
In this case, the 16-bit branch target instruction address is determined indirectly by the contents of a word GPR. In contrast to indirect data addresses,
indirectly specified code addresses are NOT calculated via additional pointer
registers (eg. DPP registers). Branches MAY NOT be taken to odd code
addresses. Therefore, the least significant bit of ’caddr’ is not used.
seg:
Specifies an absolute code segment number. The C166S V2 CPU supports
256 different code segments, so only the eight lower bits (respectively) of the
’seg’ operand value are used to update the CSP register.
#trap7: Specifies a particular interrupt or trap number for branching to the corresponding interrupt or trap service routine via a jump vector table. Trap numbers from
00H to 7FH can be specified to access any double word code location within
the address range xx’0000H...xx’15D4H (depending of VECSC) in the selected
code segment (see VECSEG, i.e. the interrupt jump vector table), please refer
to Section 5.1.4.
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2.3.2
Branch Detection and Branch Prediction
The Branch Detection Unit pre-processes instructions and classifies detected branches.
Depending on the branch class, the Branch Prediction Unit predicts the program flow
using the rules in the following table:.
Table 2-2
Branch Target Addressing Modes
Instruction Classes
Instructions
Prediction
Branch instructions with user
programmable branch
prediction
JMPA- xcc,caddr
JMPA+ xcc,caddr
CALLA- xcc, caddr
CALLA+ xcc,caddr
The User can specify whether
the branch should be taken
Branch instructions with branch JMPA xcc,caddr
prediction defined by Assembler CALLA xcc, caddr
Assembler defines whether the
branch should be taken based
on the jump condition.
Inter-segment branch
instructions
JMPS seg, caddr
CALLS seg,caddr
The branch is always taken.
Indirect branch instructions
JMPI cc,[Rw]
CALLI cc,[Rw]
The branch is taken only if the
branch is unconditional.
Relative branches instructions
with condition code
JMPR cc,rel
The branch is taken if it is
unconditional or if the branch is
a backward branch.
Relative branch instructions
without condition code
CALLR rel
The branch is always taken.
Branch instructions with
bitcondition
JB bitaddr,rel
JBC bitaddr,rel
JNB bitaddr,rel
JNBS bitaddr,rel
The branch is taken if it is a
backward branch. Forward
branches are always not taken.
Return instructions
RET
RETS
RETP
RETI
The branch is always taken.
Note: For JMPA+/- and CALLA+/- instructions, a static user programmable prediction
scheme is used. If bit 8 (’a’) of the instruction long word is cleared, the branch is
assumed ‘taken.’ If it is set, the branch is assumed ‘not taken’. The user controls
value of bit 8 by entering ’+’ or ’-’ in the instruction mnemonics. This bit can be also
set/cleared by the Assembler for JMPA and CALLA instructions depending on the
jump condition.
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Note: For JMPA instruction, a pre-fetch hint bit is used (the instruction bit 9 = l). This bit
is required by the fetch unit to deal efficiently with short backward loops. It must
be set if 0 < IP_jmpa - IP_target <= 32, where IP_jmpa is the address of the JMPA
instruction and IP_target is the target address of the JMPA. Otherwise, bit 9 must
be cleared.
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2.3.3
Sequential and Mispredicted Instruction Flow
Because passing through one pipeline stage takes at least one clock cycle, any isolated
instruction takes at least five clock cycles to be completed. Pipelining, however, allows
parallel (i.e. simultaneous) processing of up to five instructions (with branches up to six
instructions). Therefore, most of the instructions appear to be processed during one
clock cycle as soon as the pipeline has been filled once after reset.
The pipelining increases the average instruction throughput considered over a certain
period of time. In this manual, any execution time specification always refers to the
average instruction execution time due to pipelined parallel processing.
2.3.3.1
Correctly Predicted Instruction Flow
Figure 2-3 and Figure 2-4 show the continuous execution of instructions in principal
under the assumption of a fast (0 wait states) Program Memory. In this example, most
of the instructions are executed in one CPU cycle while Instruction In+6 takes two CPU
cycles for the execution. In+6 is a general example for multicycle instructions (two cycles
instruction in this case).
The instructions are fetched from the Instruction FIFO while the IFU pre-fetches the next
instructions to fill the FIFO. The Instruction FIFO is being filled with new instructions
while the previously stored instructions are being fetched from the FIFO to be executed
in the CPU. As long as the instruction flow is correctly predicted by the IFU, both
processes are independent.
I
Figure 2-3
In+21
In+21
In+20
In+20
Ia+40
In+19
In+18
In+17
In+16
Ia+32
In+16
In+15
In+15
In+14
Ia+24
In+14
In+13
In+12
In+12
Ia+16
In+11
In+11
In+10
In+10
Ia+8
In+9
In+8
In+7
In+6
Ia
Program Memory Contents for Figure 2-4
The diagram shows the sequential instruction flow through the different pipeline stages.
While the Prefetcher is prefetching the instruction from the PMU, the processing pipeline
is filled with instructions fetched out of the FIFO. In this example with a fast Internal
Program Memory, the Prefetcher is able to fetch more instructions than the processing
pipeline can execute. In Tn+4, the FIFO and prefetch buffer are filled and no further
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instructions can be prefetched. The PMU address stays stable (Tn+4) until a whole 64-bit
double word can be buffered (Tn+7) in the 96-bit Prefetch buffer again.
Tn
Tn+1
Tn+2
Tn+3
Tn+4
Tn+5
Tn+6
Tn+7
Tn+8
Ia+16
Ia+24
Ia+32
Ia+40
Ia+40
Ia+40
Ia+40
Ia+48
Ia+48
PMU Data 64bit Id+1
Id+2
Id+3
Id+4
Id+5
Id+5
Id+5
Id+5
Id+7
PREFETCH
96 bit Buffer
In+6
...
In+9
In+9
...
In+11
In+12
In+13
In+14
In+15
In+15
...
In+19
In+15
...
In+19
In+16
...
In+19
In+17
...
In+19
In+18
...
In+21
FETCH
Instruction
Buffer
In+5
In+6
In+7
In+8
In+9
In+10
In+11
In+12
In+13
In+14
-
In+15
In+16
In+17
FIFO contents
In+3
...
In+5
In+4
...
In+8
In+5
...
In+11
In+6
...
In+13
In+7
...
In+14
In+7
...
In+14
In+8
...
In+15
In+9
...
In+16
In+10
...
In+17
Fetch from FIFO In+4
In+5
In+6
In+7
In+7
In+8
In+9
In+10
In+11
DECODE
In+3
In+4
In+5
In+6
In+6
In+7
In+8
In+9
In+10
ADDRESS
In+2
In+3
In+4
In+5
In+6
In+6
In+7
In+8
In+9
MEMORY
In+1
In+2
In+3
In+4
In+5
In+6
In+6
In+7
In+8
EXECUTE
In
In+1
In+2
In+3
In+4
In+5
In+6
In+6
In+7
In
In+1
In+2
In+3
In+4
In+5
In+6
In+6
PMU Address
WRITE BACK
Figure 2-4
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2.3.3.2
Incorrectly Predicted Instruction Flow
If the CPU detects that the IFU made an incorrect prediction of the instruction flow, then
the pipeline stages and the Instruction FIFO containing the wrong prefetched instructions
are canceled. The entire instruction fetch must be restarted at the correct point of the
program. Figure 2-5 and Figure 2-6 show the behavior in the case of incorrectly
predicted instruction flow (0- wait states Internal Program Memory).
During the cycle Tn, the CPU detects an incorrectly prediction case which leads to a
canceling of the pipeline. The new address is transferred to the PMU in Tn+1 which
delivers the first data in the next cycle Tn+2. But, the target instruction crosses the 64-bit
memory boundary and a second fetch in Tn+3 is required to get the entire 32-bit
instruction. In Tn+4, the Prefetch Buffer contains two 32-bit instructions while the first
instruction Im is directly forwarded to the Decode stage.
64-bit wide Program Memory with four
16 bit packages
I...
I...
Im+5
Im+5
Im+4
Ia+24
Im+4
Im+3
Im+3
Im+2
Ia+16
Im+2
Im+1
Im+1
Im
Ia+8
Im
I...
I...
Figure 2-5
Ia
Program Memory Contents for Figure 2-6
The prefetcher is now restarted and prefetches further instructions. In Tn+5, the
instruction Im+1 is forwarded from the Fetch Instruction Buffer directly to the Decode
stage as well. The Fetch row shows all instructions in the Fetch Instruction Buffer and
the instructions fetched from the Instruction FIFO. The instruction Im+3 is the first
instruction fetched from the FIFO during Tn+6. During the same cycle, instruction Im+2
was still forwarded from the Fetch Instruction Buffer to the Decode stage.
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PMU Address
Tn
Tn+1
Tn+2
Tn+3
Tn+4
Tn+5
Tn+6
Tn+7
Tn+8
I...
Ia
Ia+8
Ia+16
Ia+24
I...
I...
I...
I...
Id
Id+1
Id+2
Id+3
I...
I...
I...
Im
Im+1
Im+2
Im+3
Im+4
Im+5
I...
I...
Im+1
Im+2
Im+3
Im+4
Im+5
I...
Im+3
Im+4
Im+5
Im+1
Im+2
Im+3
Im+4
Im
Im+1
Im+2
Im+3
Im
Im+1
Im+2
Im
Im+1
PMU Data 64bit I...
PREFETCH
96-bit Buffer
I...
FETCH
Instruction
Buffer
Inext+2
Fetch from FIFO
DECODE
Inext+1
ADDRESS
Inext
MEMORY
Ibranch
EXECUTE
In
WRITE BACK
Figure 2-6
2.3.4
Im
Ibranch
In
Ibranch
Im
Incorrectly Predicted Instruction Flow
Atomic and Extend Instructions
The atomic and extend instructions (ATOMIC, EXTR, EXTP, EXTS, EXTPR, EXTSR)
disable the standard and PEC interrupts and class A traps until completion of the
immediately following sequence of instructions. The number of instructions in the
sequence may vary from 1 to 4. It is coded in the 2-bit constant field #irang2 and takes
values from 0 to 3. The EXTended instructions additionally change the addressing
mechanism during this sequence (see instruction description).
ATOMIC and EXTended instructions become active immediately, so no additional NOPs
are required. All instructions requiring multi cycles or hold states for execution are
considered to be one instruction. The ATOMIC and EXTended instructions can be used
with any instruction type.
Note: If a class B trap interrupt occurs during an ATOMIC or EXTended sequence, then
the sequence is terminated, an interrupt lock is removed, and the standard
condition is restored before the trap routine is executed. The remaining
instructions of the terminated sequence executed after returning from the trap
routine will run under standard conditions.
Note: Certain precautions are required when using nested ATOMIC and EXTended
instructions. There is only one counter to control the length of the sequence, i.e.
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issuing an ATOMIC or EXTended instruction within a sequence will reload the
counter with the value of the new instruction.
2.3.5
Code Addressing via Code Segment and Instruction Pointer
The C166S V2 CPU provides a total addressable memory space of 16 MBytes. This
address space is arranged as 256 segments of 64 Kilobytes each. A dedicated 24-bit
code address pointer is used to access the memories for instruction fetches. This pointer
has two parts: an 8-bit code segment pointer CSP and a 16-bit offset pointer called
Instruction Pointer (IP). The concatenation of the CSP and IP results directly in a correct
24-bit physical memory address.
Memory organized in segments
255
8 7
CSP
0
15
IP
0
FF’0000H
254
FE’0000H
23
1
01’0000H
0
Figure 2-7
15
0
16 15
segment
offset
00’0000H
Addressing via the Code Segment- and Instruction Pointer
The Instruction Pointer IP
This register determines the 16-bit intra-segment address of the currently fetched
instruction within the code segment selected by the CSP register. The IP register is not
mapped into the C166S V2 CPU’s address space, and thus it is not directly accessible
by the programmer. The IP can be modified indirectly via the stack by return instructions.
The IP register is implicitly updated by the C166S V2 CPU for branch instructions and
after instruction fetch operations.
IP
Instruction Pointer
15
14
User Manual
13
12
(not addressable)
11
10
9
8
7
6
Reset Value: 0000H
5
4
3
2
1
0
IP
0
h
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Field
Bits
Type Description
IP
[15:1]
h
Specifies the intra segment offset from which the
current instruction is to be fetched. IP refers to the
current segment <SEGNR>.
0
[0]
-
IP is always word-aligned
The Code Segment Pointer CSP
This non-bit addressable register selects the code segment being used at run-time to
access instructions. The lower 8 bits of register CSP select one of up 256 segments of
64 Kilobytes each, while the higher 8 bits are reserved for future use. The reset value is
specified by the contents of the VECSEG register (Section 5.1.4).
CSP
Code Segment Pointer
SFR
Reset Value: 0000H
15
14
13
12
11
10
9
8
7
0
0
0
0
0
0
0
0
SEGNR
r
r
r
r
r
r
r
r
rh
Field
Bits
Type Description
SEGNR
[7:0]
rh
6
5
4
3
2
1
0
Specifies the code segment from which the current
instruction is to be fetched.
The actual code memory address is generated by direct extension of the 16-bit contents
of the IP register by the lower byte of the CSP register as shown in the figure below. The
CSP register can be only read and may not be written by data operations.
There are two modes: segmented and non-segmented. The mode is selected with the
SGTDIS bit in the CPUCON1 register. After reset, the segmented mode is selected.
CPUCON1
CPU Control Register 1
SFR
Reset Value: 0000H
15
14
13
12
11
10
9
8
7
6
5
0
0
0
0
0
0
0
0
0
VECSC
r
r
r
r
r
r
r
r
r
rw
4
3
2
WDT SGT INT
CTL DIS SCXT
rw
rw
rw
1
0
BP
ZCJ
rw
rw
Note: For a summary of the CPUCON1 register, please refer to Section 2.3.6.
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Field
Bits
Type Description
SGTDIS
[3]
rw
Segmentation Disable/Enable Control
0
Segmentation enabled
1
Segmentation disabled
Segmented Mode
The CSP is modified either directly by the JMPS and CALLS instructions, or indirectly via
the stack by the RETS and RETI instructions.
Upon the acceptance of an interrupt or the execution of a software TRAP instruction, the
CSP register is automatically loaded with the segment address of the vector location.
Non-Segmented Mode
In non-segmented mode, the CSP is fixed to the CSP value of the instruction that
disabled the segmentation. It is no longer possible to modify the CSP either directly by
the JMPS or CALLS instructions or indirectly via the stack by the RETS (RETI)
instruction.
In case of interrupt processing or a software TRAP instruction, the CSP register is
automatically loaded with the segment address of the vector location (VECSEG).
Note: For the correct execution of interrupt tasks, the contents of VECSEG must be the
same as the segment selected by the current value of CSP, i.e. the vector table
must be located in the segment pointed by the CSP.
Note: For Single Chip Mode, the contents of the CSP register are significant for internal
Program Memories accesses.
2.3.6
IFU Control Registers
2.3.6.1
The CPU Configuration Register CPUCON1
This register is used to configure the C166S V2 CPU. Most bits of this register enable
dedicated features of the Instruction Fetch Unit (IFU). CPICON1 may not exist in future
product derivatives.
CPUCON1
CPU Control Register 1
SFR
Reset Value: 0000H
15
14
13
12
11
10
9
8
7
6
0
0
0
0
0
0
0
0
0
VECSC
r
r
r
r
r
r
r
r
r
rw
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5
4
3
2
WDT SGT INT
CTL DIS SCXT
rw
rw
rw
1
0
BP
ZCJ
rw
rw
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Field
Bits
Type Description
VECSC
[6:5]
rw
Scaling factor of Vector Table
00
Space between two vectors is 2 words
01
Space between two vectors is 4 words
10
Space between two vectors is 8 words
11
Space between two vectors is 16 words
WDTCTL
[4]
rw
Configuration of Watch Dog Timer
0
DISWDT executable until End of Init1)
1
DISWDT/ENWDT always executable
SGTDIS
[3]
rw
Segmentation Disable/Enable Control
0
Segmentation enabled
1
Segmentation disabled
INTSCXT
[2]
rw
Enable Interruptibility of Switch Context
0
Switch context is not interruptible
1
Switch context is interruptible
BP
[1]
rw
Enable Branch Prediction Unit
0
Branch prediction disabled
1
Branch prediction enabled
ZCJ
[0]
rw
Enable Zero Cycle Jump function
0
Zero cycle jump function disabled
1
Zero cycle jump function enabled
1)
The DISWDT (executed after EINIT) and ENWDT instructions are internally converted in a NOP instruction
Note: Register CPUCON1 is only changeable in supervisor mode. Supervisor mode is
finished by executing the EINIT instruction.
2.3.6.2
The CPU Configuration Register CPUCON2
This register is used to configure the C166S V2 CPU. It is an extension of the CPUCON1
register. This register is implemented for test purposes only in the first C166S V2
demonstration devices. This register will not be implemented in production devices.
CPUCON2
CPU Control Register
15
1)
14
13
12
SFR
11
10
9
FIFODEPTH
FIFOFED
BYP
PF
rw
rw
rw
8
7
Reset Value: 0000H
6
5
4
BYP EIO
OV
STEN LFIC
F
IAEN
RUN
rw
rw
rw
rw
rw
3
2
RET FAST
ST BL1)
rw
rw
1
0
0
SL
r
rw
reserved
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Field
Bits
Type Description
FIFODEPTH
[15:12]
rw
FIFO Depth configuration
0000 No FIFO (entries)
0001 One FIFO entry
...
....
1000 Eight FIFO entries
1001 reserved
...
...
1111 reserved
FIFOFED
[11:10]
rw
FIFO Fed configuration
00
FIFO disabled
01
FIFO filled with up to one instruction per cycle
10
FIFO filled with up to two instructions per cycle
11
FIFO filled with up to three instruction per cycle
BYPPF
[9]
rw
Prefetch Bypass control
0
Bypass path from prefetch to decode disabled
1
Bypass path from prefetch to decode available
BYPF
[8]
rw
Fetch Bypass control
0
Bypass path from fetch to decode disabled
1
Bypass path from fetch to decode available
EIOIAEN
[7]
rw
Early IO Injection Acknowledge Enable
0
Injection acknowledge by destructive read not
guaranteed
1
Injection acknowledge by destructive read
guaranteed
STEN1)
[6]
rw
Stall Instruction Enable
0
Stall Instruction disabled
1
Stall Instruction enabled
LFIC
[5]
rw
Linear Follower Instruction Cache
0
Linear Follower Instruction Cache disabled
1
Linear Follower Instruction Cache enabled
OVRUN
[4]
rw
Pipeline control
0
Overrun of pipeline bubbles not allowed
1
Overrun of pipeline bubbles allowed
RETST
[3]
rw
Enable return Stack
0
Return Stack is disabled
1
Return Stack is enabled
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Field
Bits
Type Description
FASTBL2)
[2]
rw
Enables the fast injection of block transfers
0
Direct injection disabled
1
Direct injection enabled
SL
[0]
rw
Enables short loop mode
0
Short loop mode disabled
1
Short loop mode enabled
1)
enables dedicated stall debug instructions:
STALLAM da,ha,dm,hm Opcode: 44 dahadmhm
STALLEW de,he,dw,hw Opcode: 45 dehedwhw
d and h are 6 bit each
Stalls the corresponding pipeline stage after d cycles for h cycles.
2)
The FASTBL bit is implemented, but reserved. So do not use it. The block feature is implemented in the CPU,
but not used by the Interrupt and Injection Unit.
Note: Register CPUCON2 is changeable in supervisor mode only. Supervisor mode is
finished by executing the EINIT instruction.
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2.4
Use of General Purpose Registers
The C166S V2 CPU uses several banks of sixteen dedicated registers R0, R1, R2...
R15, called General Purpose Registers (GPR), which can be accessed in one CPU
cycle. The GPRs are the working registers of the arithmetic and logic units and many
also serve as address pointers for indirect addressing modes.
There are several banks of GPRs which are memory mapped and two special banks
which are not memory-mapped.
The banks of the memory-mapped GPRs are located in the internal DPRAM. One bank
uses a block of 16 consecutive words. A Context Pointer (CP) register determines the
base address of the current selected bank. Because of the required number of access
ports and access time, the GPRs located in the DPRAM cannot be accessed directly. To
get the required performance, the GPRs are cached in a 5-port register file for high
speed GPR accesses.
Core-RAM
global
Registerfile
local
AGU Write Port
Me
mo
ry
ma
pp
ed
GP
R
R15
R14
R13
R12
R11
R10
R9
R8
R7
R6
R5
R4
R3
R2
R1
R0
Ba
nk
ALU Write Port
CP
R15
R15
R14
R14
R13
R13
R12
R12
R11
R11
R10
R10
R9
R9
R8
R8
R7
R7
R6
R6
R5
R5
R4
R4
R3
R3
R2
R2
R1
R1
R0
R0
R15
R14
R13
R12
R11
R10
R9
R8
R7
R6
R5
R4
R3
R2
R1
R0
AGU Read Port
ALU Read Port 1
ALU Read Port 2
Figure 2-8
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The register file is split into three independent physical register banks. Because of
behavior differences, the banks can be distinguished as global and local register banks.
There are two local and one global register bank.
The memory-mapped GPR bank selected by the current CP is always cached in the
global register bank. Only one memory-mapped GPR bank can be cached at the time.
In the case of a context switch, the cache contents must be sequentially saved and
restored.
Note: The global register bank is the equivalent of the memory-mapped GPR bank of the
C166 family which is selected by the context pointer CP.
To support a very fast context switch for time-critical tasks, two independent not memory
mapped GPR banks are available. They are physically and logically located in the two
special local register banks. They cannot be accessed via a 24-bit physical memory
address.
Only one of the three physical register banks can be activated at the same time. The
bank selection is controlled by the BANK bitfield of the PSW. The BANK bitfield can be
changed explicitly by any instruction which writes to the PSW, or implicitly by a RETI
instruction, an interrupt or hardware trap. In case of an interrupt, the selection of the
register bank is configured in the Interrupt Controller ITC. Hardware traps always use the
global register bank.
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2.4.1
Memory Mapped GPR Banks and the Global Register Bank
The C166S V2 CPU uses the global register bank to cache an active memory-mapped
GPR bank selected by the Context Pointer (CP). The CP register value determines the
address of the first General Purpose Register (GPR) within the DPRAM of up to 16
wordwide and/or bytewide GPRs and selects the memory area which is automatically
cached in the global register bank.
Internal DPRAM
0
15
16-Bit Context Pointer
(CP)+30
(CP)+28
º
Figure 2-9
R15
R14
R13
R12
R11
R10
R9
R8
R7
R6
R5
R4
R3
R2
R1
R0
R15
R14
R13
R12
R11
R10
R9
R8
R7
R6
R5
R4
R3
R2
R1
R0
global
local
Register File
(CP)+2
(CP)
Register Bank Selection via Register CP
The General Purpose Registers of a global register bank are memory-mapped. The
behavior is identical with a cache in which the CP is used as a tag. If the global register
bank is activated, the cache will be validated before further instructions are executed.
After validation, all further accesses to the GPRs are redirected to the global register
bank. If the global register bank is activated, there are three possible ways to access the
global register bank:
Short 4-Bit GPR Addresses (mnemonic: Rw or Rb) specify addresses relative to the
memory location pointed by the contents of the CP register, i.e. the base of contents of
the current global register bank. Both byte and word GPR accesses are possible. The
short 4-bit GPR address is logically added to the contents of register CP in the case a
byte (Rb) GPR address is specified, or multiplied by two and then added to CP; in case
of a word (Rw) GPR address (see figure below).
Note: If GPRs are used as indirect address pointers, they are always accessed
wordwise.
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For some instructions, only the first four GPRs can be used as indirect address pointers.
These GPRs are specified via short 2-bit GPR addresses. The respective physical
address calculation is identical with the one for the short 4-bit GPR addresses.
Short 8-Bit Register Addresses (mnemonic: reg or bitoff) within a range from F0H to
FFH interpret the four least significant bits as short 4-bit GPR addresses, while the four
most significant bits are ignored. The respective physical GPR address is calculated
similar to the short 4-bit GPR addresses. For single bit GPR accesses, the GPR’s word
address is calculated in the same way. The accessed bit position within the word is
specified by a separate additional 4-bit value.
Specified by reg or bitoff
12-Bit Context Pointer
11
1 0
1 1 1 1 4-Bit GPR
address
For byte GPR
*1
accesses
*2
For word GPR
accesses
Internal
DPRAM
+
Must be within
the internal
DPRAM area
GPRs
Figure 2-10 Implicit CP Use by logical Short GPR Addressing Modes
.
24-Bit Memory Addresses can be directly used to access GPRs. In this case, the CPU
immediately starts the memory access. At the same time, a hit detection logic checks if
the accessed memory location is cached in the global register bank. In case of a cache
hit, an additional global register bank read access is initiated. The data that is read from
cache will be used and the data that is read from memory will be discarded. This leads
to a delay of one CPU cycle (MOV R4,mem [CP<=mem<=CP+31]). In case of memory
write access, the hit detection logic determines a cache hit in advance. Nevertheless, the
address conversion needs one additional CPU cycle. The value is directly written into the
global register bank without further delay (MOV mem,R4).
Note: The 24-bit GPR addressing mode is not recommended because it requires an
extra cycle for the read and write access.
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.
Table 2-3
Addressing Modes to Access Word-GPRs
4-Bit
Description
Name Physical 8-Bit
Address Address Address
Reset
Value
1)
R0
(CP)+0
F0H
0h
General Purpose Word Register R0
UUUUH
R1
(CP)+2
F1H
1h
General Purpose Word Register R1
UUUUH
R2
(CP)+4
F2H
2h
General Purpose Word Register R2
UUUUH
R3
(CP)+6
F3H
3h
General Purpose Word Register R3
UUUUH
R4
(CP)+8
F4H
4h
General Purpose Word Register R4
UUUUH
R5
(CP)+10 F5H
5h
General Purpose Word Register R5
UUUUH
R6
(CP)+12 F6H
6h
General Purpose Word Register R6
UUUUH
R7
(CP)+14 F7H
7h
General Purpose Word Register R7
UUUUH
R8
(CP)+16 F8H
8h
General Purpose Word Register R8
UUUUH
R9
(CP)+18 F9H
9h
General Purpose Word Register R9
UUUUH
R10
(CP)+20 FAH
Ah
General Purpose Word Register R10 UUUUH
R11
(CP)+22 FBH
Bh
General Purpose Word Register R11 UUUUH
R12
(CP)+24 FCH
Ch
General Purpose Word Register R12 UUUUH
R13
(CP)+26 FDH
Dh
General Purpose Word Register R13 UUUUH
R14
(CP)+28 FEH
Eh
General Purpose Word Register R14 UUUUH
R15
(CP)+30 FFH
Fh
General Purpose Word Register R15 UUUUH
1)
Addressing mode only usable if the GPR bank is memory mapped.
Note: The first 8 GPRs (R7...R0) may also be accessed bytewise.
Note: Writing to a GPR byte does not affect the other byte of the respective GPR.
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The respective halves of the byte-accessible registers have special names (see
Table 2-4). .
Table 2-4
Addressing modes to access Byte-GPRs
Name Physical 8-Bit
4-Bit
Description
Address Address Address
Reset
Value
1)
RL0
(CP)+0
F0H
0h
General Purpose Byte Register RL0
UUH
RH0
(CP)+1
F1H
1h
General Purpose Byte Register RL1
UUH
RL1
(CP)+2
F2H
2h
General Purpose Byte Register RL2
UUH
RH1
(CP)+3
F3H
3h
General Purpose Byte Register RL3
UUH
RL2
(CP)+4
F4H
4h
General Purpose Byte Register RL4
UUH
RH2
(CP)+5
F5H
5h
General Purpose Byte Register RL5
UUH
RL3
(CP)+6
F6H
6h
General Purpose Byte Register RL6
UUH
RH3
(CP)+7
F7H
7h
General Purpose Byte Register RL7
UUH
RL4
(CP)+8
F8H
8h
General Purpose Byte Register RL8
UUH
RH4
(CP)+9
F9H
9h
General Purpose Byte Register RL9
UUH
RL5
(CP)+10 FAH
Ah
General Purpose Byte Register RL10 UUH
RH5
(CP)+11 FBH
Bh
General Purpose Byte Register RL11 UUH
RL6
(CP)+12 FCH
Ch
General Purpose Byte Register RL12 UUH
RH6
(CP)+13 FDH
Dh
General Purpose Byte Register RL13 UUH
RL7
(CP)+14 FEH
Eh
General Purpose Byte Register RL14 UUH
RH7
(CP)+15 FFH
Fh
General Purpose Byte Register RL15 UUH
1)
Addressing mode only usable if the GPR bank is memory mapped.
Note: Even if the local register bank is selected by BANK, an old memory-mapped GPR
bank can be cached in the global register bank. Memory accesses are still
redirected in case of a cache hit.
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2.4.2
Local Register Bank
C166S V2 CPU has two local register banks with sixteen independent GPRs each. Both
local register banks are not memory mapped. After a switch to a local register bank, the
GPRs are directly accessible. There are two different ways to access an activated local
register bank.
Short 4-Bit GPR Addresses (mnemonic: Rw or Rb) specify addresses in the local
register banks. The local register bank is selected by the BANK bitfield of the PSW.
Depending on whether a relative word (Rw) or byte (Rb) GPR address is specified, the
short 4-bit GPR address is either multiplied by two or not before it is used to physically
access the local register bank. Thus, both byte and word GPR accesses are possible in
this way.
Note: If GPRs are used as indirect address pointers, they are always accessed
wordwise.
For some instructions, only the first four GPRs can be used as indirect address pointers.
These GPRs are specified via short 2-bit GPR addresses. The respective physical
address calculation is identical with the one for the short 4-bit GPR addresses.
Short 8-Bit Register Addresses (mnemonic: reg or bitoff) within a range from F0H to
FFH interpret the four least significant bits as short 4-bit GPR address, while the four
most significant bits are ignored. The respective physical GPR address calculation is
identical with the one for the short 4-bit GPR addresses. For single bit accesses on a
GPR, the GPR’s word address is calculated as just described, but the position of the bit
within the word is specified by a separate additional 4-bit value.
For a summary of all addressing modes usable to access GPRs, please see Table 2-3
and Table 2-4.
2.4.3
Context Switch
An interrupt service routine or a task scheduler of an operating system usually saves into
the stack all the used registers and restores them before returning. The more registers
a routine uses, the more time is wasted with saving and restoring. There are two ways
to change a context in the C166S V2 core:
• Switching the context by changing the selected register banks.
• Switching the context of the global register bank by changing the context pointer CP.
2.4.3.1
Changing the selected Physical Register Bank
The switch between the three physical register banks is the fastest possible context
switch. It is possible to switch between the current memory-mapped GPR bank located
in the global register bank and the two not memory-mapped local register banks. The
BANK bit field of the PSW register determines the selected bank.
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PSW
Processor Status Word
15
14
13
12
SFRb
11
10
9
8
ILVL
IEN
HLD
EN
BANK
rwh
rw
rw
rwh
Reset Value: 0000H
7
6
USR1 USR0
rwh
rwh
Field
Bits
Type Description
BANK
9-8
rwh
5
4
3
2
1
0
MUL
IP
E
Z
V
C
N
rwh
rwh
rwh
rwh
rwh
rwh
Reserved for register file bank selection
00
Global register bank
01
Reserved
10
Local register bank 1
11
Local register bank 2
In case of an interrupt service, the bank switch is automatically executed by updating the
PSW. The Interrupt Controller (ITC) configuration decides which register bank will be
selected. By executing a RETI instruction, the BANK bit field of the PSW will
automatically be restored and the context will switched to the original register bank.
global
Bank
local
Bank
global
Bank
Execution
Task A
Execution
Task B
Execution
Task A
Execution of
RETI
Interrupt of Task B
recognized
Figure 2-11 Context Switch by Changing the Physical Register Bank
After a switch to a local register bank, the new bank is immediately available. After
switching to the global register bank, the cached memory-mapped GPRs must be valid
before any further instructions can be executed. If the global register bank is not valid at
this time (in case if the context switch process has been interrupted), the cache
validation process is repeated automatically. For further explanation, please refer to
Section 2.4.3.2.
Note: The switch between the three physical register banks of the register file can also
be executed by writing to the BANK bitfield of the PSW. Because of pipeline
dependencies an explicit change of the PSW must cancel the pipeline.
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2.4.3.2
Context Switching of the Global Register Bank
The contents of the global register bank are switched by changing the base address of
the memory mapped GPR bank. The base address is given by the contents of the
Context Pointer (CP).
The Context Pointer (CP)
The CP register is non-bit addressable. It can be updated via any instruction capable of
modifying SFRs.
CP
Context Pointer
SFR
11
10
9
15
14
13
12
1
1
1
1
CONTEXT POINTER
0
r
r
r
r
rw
r
Field
Bits
1
[15:12] r
8
7
Reset Value: FC00H
6
5
4
3
2
1
0
Type Description
CP always points in the internal DPRAM
CONTEXT POINTER [11:1]
rw
Modifiable Portion of register CP
Specifies the (word) base address of the current
memory-mapped register bank.
When writing a value to register CP with bits
CP[11:9] = ’000’, bits CP[11:10] are set to ’11’
by hardware.
0
r
CP is always word-aligned
[0]
Note: It is the user’s responsibility that the physical GPR address specified via CP
register plus the short GPR address must always be an internal DPRAM location.
If this condition is not met, unexpected results may occur. Do not set CP below the
internal DPRAM start address.
Note: Due to the internal instruction pipeline, a write operation to the CP register stalls
the instruction flow until the register file context switch is really executed. The
instruction immediately following the instruction that updates CP register can use
the new value of the changed CP.
The C166S V2 CPU switches the complete memory-mapped GPR bank with a single
instruction. After switching, the service routine executes within its own separate context.
The instruction “SCXT CP, #New_Bank” pushes the value of the current context pointer
(CP) into the system stack and loads CP with the immediate value “New_Bank”, which
selects a new register bank. The service routine may now use its “own registers”. This
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memory register bank is preserved when the service routine terminates, i.e. its contents
is available on the next call.
Before returning from the service routine (RETI), the previous CP is simply popped from
the system stack which returns the registers to the original bank.
Context Pointer Updating
After the CP has been update, a state machine starts to store the old contents of the
global register bank and to load the new one. An instruction “SCXT CP, #New_Bank”
takes two cycles. The store and load algorithm is executed in nineteen CPU cycles: the
execution of the cache validation process takes sixteen cycles plus three cycles to stall
an instruction execution to avoid pipeline conflicts upon the completion of the validation
process. The context switch process has two phases:
1. Store phase: The contents of the global register bank is stored back into the DPRAM
by executing eight injected STORE instructions. After the last STORE instruction the
contents of the global register bank are invalidated.
2. Load phase: The global register bank is loaded with the new context by executing
eight injected LOAD instructions. After the last LOAD instruction the contents of the
global register bank are validated.
The code execution is stopped until the global register bank is valid. A hardware interrupt
which also uses a global register bank cannot be executed until the validation process is
finished (see Figure 2-12).
global
Bank
Execution
Task A
global
Bank
Execution
Task B
Execution of
SCXT CP
Interrupt of Task B
recognized
Execution of
SCXT CP
Execution
Task B
Execution of
POP CP
Register Bank
validation
process
started
global
Bank
finished
Execution
Task B
Register Bank
validation
process
started
Execution
Task A
Execution of
RETI
finished
Register Bank
validation
process
started
finished
Figure 2-12 Validation process and hardware interrupts using a global register
bank
But, the validation process can be interrupted by any hardware interrupt which will work
with a local register bank. After switching back to the global register bank, the validation
process must be finished. The way the validation process will be restarted depends on
the phase in which it has been interrupted.
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If the interrupt occurred before the load phase, the entire validation process is restarted
from the very beginning. If the store phase has been completed before the interrupt, only
the load phase is executed.
global
Bank
local
Bank
Execution
Task A
global
Bank
Execution
Task B
Execution
Task A
Execution of
RETI
Interrupt of Task B
recognized
Execution of
SCXT CP
Register Bank
validation
process
started
Register Bank
validation
process
stopped
restarted finished
Note: Validation Process and Hardware Interrupts using a Local Register Bank
Note: A cache validation process of Task A can be interrupted by a Task B which uses
a local register bank. Task B itself is interrupted again by an interrupt Task C which
uses a global register bank again. In this case, the validation process of Task A
must be finished before code of Task C can be executed. This means that the
validation process of Task A does not affect the interrupt latency of Task B but the
latency of Task C. If Task C would immediately interrupt Task A, the register bank
validation process of Task A would be finished first. The worst case interrupt
latency is identical in both cases (see Figure 2-12 and Figure 2-13).
.
global
Bank
local
Bank
Execution
Task A
global
Bank
Execution
Task B
Interrupt of Task C
recognized
Interrupt of Task B
recognized
Execution
Task C
Register Bank
validation
process
restarted finished
local
Bank
global
Bank
Execution
Task B
Execution
Task A
Execution of
RETI
Execution of
RETI
Execution of
SCXT CP
Register Bank
validation
process
started
stopped
Figure 2-13 Validation Process and Hardware Interrupts using Local and Global
Register Bank
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2.5
Data Addressing
The Address Data Unit (ADU) of the C166S V2 CPU contains two independent
arithmetic units to generate, calculate, and update addresses for data accesses. The
ADU performs the following major tasks:
•
•
•
•
Standard Address Generation (Standard Address Generation Unit)
DSP Address Generation (DSP Address Unit)
Data Paging (Standard Address Unit)
Stack Handling (Standard Address Unit)
The Standard Address Unit supports linear arithmetic for the indirect addressing modes
and also generates the address in case of all other short and long addressing modes.
The DSP Address Generation Unit contains an additional set of address pointers and
offset registers which are used in conjunction with the CoXXX instructions only.
The C166S V2 CPU provides a lot of powerful addressing modes for word, byte, and bit
data accesses (short, long, indirect). The different addressing modes use different
formats and have different scopes.
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2.5.1
Short Addressing Modes
All of these addressing modes use an implicit base offset address to specify a 24-bit
physical address.
Short addressing modes allow access to the GPR, SFR or bit addressable memory
space:
Physical Address = Base Address + ∆ * Short Address
Note: ∆ is 1 for byte GPRs, ∆ is 2 for word GPRs..
Table 2-5
Short addressing modes
Mnemonic Physical Address
Short Address
Range
Scope of Access
Rw
(CP) + 2*Rw or local
Rw
= 0...15
GPRs(Word)
Rb
(CP) + 1*Rb or local
Rb
= 0...15
GPRs(Byte)
reg
00’FE00H + 2*reg
00’F000H + 2*reg
(CP)+2*(reg∧0FH) or local
(CP)+1*(reg∧0FH) or local
reg
reg
reg
reg
= 00H...EFH
= 00H...EFH
= F0H...FFH
= F0H...FFH
SFRs (Word, Low byte)
ESFRs(Word, Low byte)
GPRs(Word)
GPRs(Bytes)
bitoff
00’FD00H + 2*bitoff
00’FF00H + 2*(bitoff∧7FH)
00’F100H + 2*(bitoff∧7FH)
(CP) + 2*(bitoff∧0FH) or
local
bitoff
bitoff
bitoff
bitoff
= 00H...7FH
= 80H...EFH
= 80H...EFH
= F0H...FFH
RAM Bit word offset
SFR Bit word offset
ESFR Bit word offset
GPR Bit word offset
bitaddr
Word offset as with bitoff. bitoff = 00H...FFH
bitpos= 0...15
Immediate bit position.
Any single bit
Rw, Rb: Specifies direct access to any GPR in the currently active context (global register bank or local register bank). Both ’Rw’ and ’Rb’ require four bits in the
instruction format.The base address of the global register bank is determined
by the contents of register CP. ’Rw’ specifies a 4-bit word GPR address relative
to the base address (CP), while ’Rb’ specifies a 4-bit byte GPR address relative to the base address (CP). In case of an active local register bank this 4
bits are used directly to address the GPR.
reg:
Specifies direct access to any (E)SFR or GPR in the currently active context
(global or local register bank). The ’reg’ value requires eight bits in the instruction format. Short ’reg’ addresses in the range from 00H to EFH always specify
(E)SFRs. In that case, the factor ’D’ equates 2 and the base address is
00’FE00H for the standard SFR area or 00’F000H for the extended ESFR
area. The ‘reg’ accesses to the ESFR area require a preceding EXT*R instruction to switch the base address. Depending on the opcode, either the total
word (for word operations) or the low byte (for byte operations) of an SFR can
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be addressed via ’reg’. Note that the high byte of an SFR cannot be accessed
via the ’reg’ addressing mode. Short ’reg’ addresses in the range from F0H to
FFH always specify GPRs. In that case, only the lower four bits of ’reg’ are significant for physical address generation and, therefore, it is identical to the
address generation described for the ’Rb’ and ’Rw’ addressing modes.
bitoff:
Specifies direct access to any word in the bit addressable memory space. The
’bitoff’ value requires eight bits in the instruction format. Depending on the
specified ’bitoff’ range different base addresses are used to generate physical
addresses: Short ’bitoff’ addresses in the range from 00H to 7FH use
00’FD00H as a base address to specify the 128 highest internal RAM word
locations in the range from 00’FD00Hh to 00’FDFEH. Short 'bitoff' addresses in
the range from 80H to EFH use base address 00’FF00H to specify the internal
SFR word locations in the range from 00’FF00H to 00’FFDEH or base address
00’F100H to specify the internal ESFR word locations in the range from
00’F100H to 00’F1DEH. The ‘bitoff’ accesses to the ESFR area require a preceding EXT*R instruction to switch the base address. For short 'bitoff'
addresses from F0H to FFH, only the lowest four bits are used to generate the
address of the selected word GPR.
bitaddr: Any bit address is specified by a word address within the bit addressable
memory space (see 'bitoff'), and by a bit position ('bitpos') within that word.
Therefore, 'bitaddr' requires twelve bits in the instruction format.
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2.5.2
Long and Indirect Addressing Modes
These addressing modes use one of the four DPP registers to specify a 24-bit address.
Any word or byte data within the entire address space can be accessed with these
modes.
Any long or indirect 16-bit address contain two parts that have different meanings. Bits
13...0 specify a 14-bit data page offset, while bits 15...14 specify the Data Page Pointer
(DPP) (1 of 4) register used to generate the full 24-bit address (see Figure 2-14).
The C166S V2 CPU also supports an override mechanism for the DPP addressing
scheme (EXTP(R) and EXTS(R) instructions). See following sections for details.
15 14 13
0
16-bit Long Address
DPP0
DPP1
DPP2
DPP3
14-bit page offset
24-bit Physical Address
Figure 2-14
Interpretation of a 16-bit Long Address
Note: Word accesses on odd byte addresses are not executed. A hardware trap will be
triggered.
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2.5.2.1
Addressing via Data Page Pointer DPP
The four non-bit addressable Data Page Pointer registers select up to four different data
pages. The lower 10 bits of each DPP register select one of the 1024 possible 16Kilobyte data pages while the upper 6 bits are reserved for the future use. The DPP
registers provide an access to the entire memory space in 16 Kilobytes pages.
The DPP registers are implicitly used whenever data accesses to any memory location
are made via indirect or direct long 16-bit addressing modes (except for override
accesses via EXTended instructions and PEC data transfers).
Data paging is performed by concatenating the lower 14-bits of an indirect or direct long
16-bit address with the contents of the DDP register selected by the upper two bits of the
16-bit address. The contents of the selected DPP register specifies one of the 1024
possible data pages. This data page base address together with the 14-bit page offset
forms the physical 24-bit address.
16-Bit Data Address
15 14
0
Memory
selects DPP
255
FF’0000H
9
DPP
0
DPP3 - 11
254
DPP2 - 10
FE’0000H
DPP1 - 01
DPP0 - 00
x
23
1
15 14
0
01’0000H
0
00’0000H
Page
Page offset
Segment
Segment offset
Figure 2-15 Data Page Pointer Addressing
After reset, the DPP registers select data pages 3...0 within segment 0. If the user does
not want to use any data paging, no further action is required.
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DPP0
Data Page Pointer 0
SFR
9
15
14
13
12
11
10
0
0
0
0
0
0
PN
r
r
r
r
r
r
rw
DPP1
Data Page Pointer 1
8
7
Reset Value: 0000H
6
5
4
SFR
9
7
14
13
12
11
10
0
0
0
0
0
0
PN
r
r
r
r
r
r
rw
6
5
4
SFR
9
7
14
13
12
11
10
0
0
0
0
0
0
PN
r
r
r
r
r
r
rw
6
5
4
SFR
9
8
7
14
13
12
11
10
0
0
0
0
0
0
PN
r
r
r
r
r
r
rw
Bits
Type Description
PN
[9:0]
rw
0
3
2
1
0
3
2
1
0
Reset Value: 0003H
15
Field
1
Reset Value: 0002H
15
DPP3
Data Page Pointer 3
8
2
Reset Value: 0001H
15
DPP2
Data Page Pointer 2
8
3
6
5
4
3
2
1
0
Data Page Number of DPP
Specifies the data page selected via DPP.
Note: In case of non-segmented memory mode, the entire DPP register is still used for
the calculation of the physical 24-bit address.
A DPP register can be updated via any instruction capable of modifying an SFR.
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Note: Due to the internal instruction pipeline, a write operation to the DPPx registers
could stall the instruction flow until the DPP is actually updated. The instruction
that immediately follows the instruction which updates the DPP register can use
the new value of the changed DPPx.
2.5.2.2
DPP Override Mechanism in the C166S V2 CPU
The C166S V2 CPU provides an override mechanism for the temporary bypass of the
DPP addressing scheme.
The EXTP(R) and EXTS(R) instructions override this addressing mechanism. Instruction
EXTP(R) replaces the contents of the respective DPP register, while instruction
EXTS(R) concatenates the complete 16-bit long address with the specified segment
base address. The overriding page or segment may be specified directly as a constant
(#pag, #seg) or via a word GPR (Rw).
15 14 13
EXTP(R):
0
16-bit Long Address
#pag
14-bit page offset
24-bit Physical Address
15
EXTS(R):
0
16-bit Long Address
#seg
16-bit segment offset
24-bit Physical Address
Figure 2-16
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2.5.2.3
Long Addressing Mode
The long addressing mode uses a 16-bit constant value encoded in the instruction format
which specifies the data page offset and the DPP.
The long addressing mode is referred to by the mnemonic ‘mem’. .
Table 2-6
Long Addressing Modes
Mnemonic
Physical Address
Scope of Access
mem
(DPP0) || mem∧3FFFH
(DPP1) || mem∧3FFFH
(DPP2) || mem∧3FFFH
(DPP3) || mem∧3FFFH
Any Word or Byte
mem
pag || mem∧3FFFH
Any Word or Byte
mem
seg || mem
Any Word or Byte
Note: The long addressing may be used with the DPP overriding mechanism (EXTP(R)
and EXTS(R)).
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2.5.2.4
Indirect Addressing Modes
These addressing modes can be considered as a combination of short and long
addressing modes. This means that long 16-bit address is provided indirectly by the
contents of a word GPR which is specified directly by a short 4-bit address (’Rw’=0 to
15). There are indirect addressing modes, which add a constant value to the GPR
contents before the long 16-bit address is calculated. Other indirect addressing modes
can decrement or increment the indirect address pointers (GPR contents) by 2 or 1
(referring to words or bytes) or by the contents of the offset registers QR0 and QR1.
The Offset Register QR0 and QR1
There are two non-bit addressable offset registers QR0 and QR1 which can be used in
conjunction with the CoXXX instructions.
QR0
Offset Register
15
14
13
ESFR
12
11
10
9
QR1
Offset Register
15
14
13
8
7
Reset Value: 0000H
6
5
4
11
10
9
2
1
0
QR
0
rw
r
ESFR
12
3
8
7
Reset Value: 0000H
6
5
4
3
2
1
0
QR
0
rw
r
Field
Bits
Type Description
QR
[15:1]
rw
Modifiable portion of register QRx
Specifies the 16-bit offset address for indirect
addressing modes.
0
[0]
r
Fixed to 0
Note: During initialization of the QR registers, instruction flow stalls are possible. For the
proper operation refer to Chapter 4.1.4.
In each case, one of the four DPP registers is used to specify physical 24-bit addresses.
Any word or byte data within the entire memory space can be addressed indirectly.
Note: The indirect addressing may be used with the DPP overriding mechanism
(EXTP(R) and EXTS(R)).
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Some instructions only use the lowest four word GPRs (R3...R0) as indirect address
pointers, which are specified via short 2-bit addresses in that case.
Physical addresses are generated from indirect address pointers using the following
algorithm:
1)
Calculate the physical address of the word GPR, which is used as indirect
address pointer, using the specified short address (’Rw’) and
- the current global register bank
GPR Address = (CP) + 2 * Short Address
- the current local register bank
GPR Address = 2 * Short Address.
2)
If required, pre-decremented indirect address pointer (‘-Rw’) by the data-typedependent value (D=1 for byte operations, D=2 for word operations) before
the long 16-bit address is generated:
(GPR Address) = (GPR Address) - D ; [optional step!]
3)
Calculate the long 16-bit address by adding a constant value (’Rw+const16’ if
selected) to the contents of the indirect address pointer:
Long Address = (GPR Pointer) + Constant ; [+Constant is optional]
4)
Calculate the physical 24-bit address using the resulting long address and the
corresponding DPP register contents (see long 'mem' addressing modes).
Physical Address = (DPPi) + Page offset
5)
- If required, post-in/decrement indirect address pointers (‘Rw±’) by the datatype-dependent value (D=1 for byte operations, D=2 for word operations).
- If required, post-in/decrement indirect address pointers (‘Rw± QRx’) by
D=QRx:
(GPR Pointer) = (GPR Pointer) ± D ; [optional step!]
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The following indirect addressing modes are provided: .
Table 2-7
Indirect Addressing Modes
Mnemonic
Particularities
[Rw]
Most instructions accept any GPR (R15...R0) as indirect address
pointer. Some instructions accept only the lower four GPRs (R3...R0).
[Rw+]
The specified indirect address pointer is automatically post-incremented
by 2 or 1 (for word or byte data operations) after the access.
[-Rw]
The specified indirect address pointer is automatically pre-decremented
by 2 or 1 (for word or byte data operations) before the access.
[Rw+#data16] The specified 16-bit constant is added to the indirect address pointer,
before the long address is calculated.
[Rw-]
The specified indirect address pointer is automatically postdecremented by 2 (word data operations) after the access.
[Rw+QRx]
The specified indirect address pointer is automatically post-incremented
by QRx (word data operations) after the access.
[Rw-QRx]
The specified indirect address pointer is automatically postdecremented by QRX (word data operations) after the access.
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2.5.3
DSP Addressing
In addition to the Standard Address Generation Unit, the DSP Address Generation Unit
provides an additional set of pointer and offset registers. An independent arithmetic unit
allows the update of these dedicated pointer registers in parallel with the GPR-Pointer
modification of the Standard Address Generation Unit. The DSP Address Generation
Unit only supports indirect addressing modes that use the special pointer registers IDX0
and IDX1.
The Pointer Register IDX0 and IDX1
The additional set of pointer registers IDX0 and IDX1 allows the execution of DSP
specific CoXXX instruction in one CPU cycle.
IDX0
Address Pointer
15
14
13
SFRb
12
11
10
9
IDX1
Address Pointer
15
14
13
8
7
Reset Value: 0000H
6
5
4
11
10
9
2
1
0
IDX
0
rw
r
SFRb
12
3
8
7
Reset Value: 0000H
6
5
4
3
2
1
0
IDX
0
rw
r
Field
Bits
Type Description
IDX
[15:1]
rw
Modifiable portion of register IDXx
Specifies the 16-bit value of a dedicated address
pointer.
0
[0]
r
Fixed to 0
Note: During the initialization of the IDX registers, instruction flow stalls are possible. For
the proper operation, refer to the Section 4.1.4.
The address pointers can be used for arithmetic operations as well as for the special
CoMOV instruction. But, the generation of the 24 bit memory address is different.
In case of arithmetic CoXXX operations, the IDX pointers are automatically zero
extended to a 24-bit memory address. The IDX address pointers should point to the
internal DPRAM area. Even if the IDX address pointers do not point to the internal
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DPRAM area, the address is mapped into the DPRAM area. The leading four bits of the
IDX pointers are not taken into account as shown in Figure 2-17.
16-Bit IDX Pointer
15
Memory
12 11
0
2
02’0000H
1
01’0000H
DPRAM in Data Page 3
23
0
00000000
15
12 11
0
1111
00’0000H
Figure 2-17 Arithmetic MAC Operations and Addressing via the IDX Pointers
For CoMOV MAC operation, the IDX pointers are concatenated with the Data Page
Pointers, just like normal GPR-Pointers as described in Section 2.5.2.1. The IDX pointer
can address the entire C166S V2 memory area without any restrictions.
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16-Bit Data Address (IDXx)
15 14
0
Memory
selects DPP
255
FF’0000H
9
DPP
0
DPP3 - 11
254
DPP2 - 10
FE’0000H
DPP1 - 01
DPP0 - 00
x
23
1
15 14
0
01’0000H
0
00’0000H
Page
Page offset
Segment
Segment offset
Figure 2-18 CoMOV Operations and Addressing via the IDX Pointers
There are indirect addressing modes which allow parallel data move operations before
the long 16-bit address is calculated. Other indirect addressing modes allow
decrementing or incrementing the indirect address pointers (IDXx contents) by 2 or by
the contents of the offset registers. There are two non-bit addressable offset registers
QX0 and QX1 which can be used in conjunction with the CoXXX instructions.
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The Offset Register QX0 and QX1
These two non-bit addressable registers are used only for CoXXX operations which
access operands using indirect addressing mode. The QX offset registers are used in
conjunction with the IDX pointers.
QX0
Offset Register
15
14
13
ESFR
12
11
10
9
QX1
Offset Register
15
14
13
8
7
Reset Value: 0000H
6
5
4
11
10
9
2
1
0
QX
0
rw
r
ESFR
12
3
8
7
Reset Value: 0000H
6
5
4
3
2
1
0
QX
0
rw
r
Field
Bits
Type Description
QX
[15:1]
rw
Modifiable portion of register QXx
Specifies the 16-bit offset address for indirect
addressing modes.
0
[0]
r
Fixed to 0
Note: During the initialization of the QX registers, instruction flow stalls are possible. For
the proper operation, refer to the Section 4.1.4.
Physical addresses are generated from indirect address pointers IDX via the following
algorithm:
1)
Determine the used IDXx pointer
2)
An intermediate long address is calculated for the parallel data move operation of CoXXXM instructions before the long 16-bit address is generated
[optional step!]:
- If required, indirect address pointers (‘IDXx±’) are de/incremented by D=2.
- If required, indirect address pointers (‘IDXx± QXx’) are de/incremented by
D= QXx.
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Intermediate Address = (IDXx Address) ± D ; [optional step!]
3)
Calculate long 16-bit address:
Long Address = (IDXx Pointer)
4)
Calculate the physical 24-bit address using the resulting long address and the
corresponding DPP register contents (see long ’mem’ addressing modes and
DPPi override mechanism for arithmetic CoXXX instructions).
Physical Address = (DPPi) + Page offset
5)
- If required, indirect address pointers (‘IDXx±’) are in/decremented by D=2 for
word operations.
- If required, indirect address pointers (‘IDXx± QXx’) are in/decremented by
D= QXx for word operations.
(IDX Pointer) = (IDX Pointer) ± D; [optional step!]
The following indirect addressing modes are provided: .
Table 2-8
DSP Addressing Modes
Mnemonic
Particularities
[IDXx]
Most CoXXX instructions accept IDXx (IDX0, IDX1) as an indirect
address pointer.
[IDXx+]
The specified indirect address pointer is automatically post-incremented
by 2 after the access.
with parallel
data move
In case of a CoXXXM instruction, the address stored in the specified
indirect address pointer is automatically pre-decremented by 2 for the
parallel move operation. The pointer itself is not pre-decremented.
Then, the specified indirect address pointer is automatically postincremented by 2 after the access.
[IDXx-]
The specified indirect address pointer is automatically postdecremented by 2 after the access.
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Table 2-8
DSP Addressing Modes (cont’d)
Mnemonic
Particularities
with parallel
data move
In case of a CoXXXM instruction, the address stored in the specified
indirect address pointer is automatically pre-incremented by 2 for the
parallel move operation. The pointer itself is not pre-incremented. Then,
the specified indirect address pointer is automatically post-decremented
by 2 after the access.
[IDXx+QXx]
The specified indirect address pointer is automatically post-incremented
by QXx after the access.
with parallel
data move
In case of a CoXXXM instruction, the address stored in the specified
indirect address pointer is automatically pre-decremented by QXx for
the parallel move operation. The pointer itself is not pre-decremented.
Then, the specified indirect address pointer is automatically postincremented by QXx after the access.
[IDXx-QXx]
The specified indirect address pointer is automatically postdecremented by QXx after the access.
with parallel
data move
In case of a CoXXXM instruction, the address stored in the specified
indirect address pointer is automatically pre-incremented by QXx for the
parallel move operation. The pointer itself is not pre-incremented. Then,
the specified indirect address pointer is automatically post-decremented
by QXx after the access.
The example in Figure 2-19 shows the complex operation of CoXXX instructions with a
parallel move operation based on the descriptions about addressing modes given in
Section 2.5.2.4 (Indirect Addressing Modes) and Section 2.5.3 (DSP Addressing
Modes).
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CoXXXMxx [IDX0+],[R2+]
Address operations
1) calculate pointer addresses
IDXx = IDX0
R2 Address = CP + 2*2
(global register bank)
2) intermediate address of write pointer
for the parallel mov operation
Intermediate Address = (IDX0) - 2
3) calculate long 16bit address
Long Address 1 = (IDX0)
Long Address 2 = (R2)
4) calculate 24bit physical address
Physical Address 1 = Page3 + Page offset Physical Address 2 = (DPPi) + Page offset
5) post modify address pointer
(IDX0)new = (IDX0) + 2
(R2)new = (R2) + 2
Data operations
1)
Read operands
op1 = (Physical Address 1)
op2 = (Physical Address 2)
2) Write operand op1
(Intermediate Address) = op1
(IDX0)new (updated pointer)
op1
parallel
move
(IDX0)
(R2)new (updated pointer)
op2
(read pointer)
(R2)
(read pointer)
Intermediate Address
(write pointer for parallel move)
Figure 2-19 Arithmetic MAC Operations with Parallel Move
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2.5.4
The CoREG Addressing Mode
The CoSTORE instruction utilizes the special CoREG addressing mode for immediate
storage of the MAC-Unit register after a MAC operation. The address of the MAC-Unit
register is coded in the CoSTORE instruction format as described in the following table:
.
Table 2-9
Coding of the CoREG Addressing Mode
Mnemonic
Register
Coding of wwww:w bits [31:27]
MSW
MAC-Unit Status Word
00000
MAH
MAC-Unit Accumulator High Word
00001
MAS
Limited MAC-Unit Accumulator High 00010
Word
MAL
MAC-Unit Accumulator Low Word
00100
MCW
MAC-Unit Control Word
00101
MRW
MAC-Unit Repeat Word
00110
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2.5.5
The System Stack
The C166S V2 CPU supports a system stack of 64 kBytes. The stack can be located
internally in one of the on-chip memories or externally. The 16-bit Stack Pointer (SP)
register addresses the stack within a 64 kByte segment. The Stack Pointer Segment
Register (SPSG) selects the segment in which the stack is located. A virtual stack
(usually bigger then 64 kBytes) can be implemented by software. This mechanism is
supported by registers STKOV and STKUN (see descriptions below).
The Stack Pointer Register SP
The non-bit addressable Stack Pointer SP register is used to point to the top of the
system stack (TOS). The SP register is pre-decremented whenever data is to be pushed
onto the stack, and it is post-incremented whenever data is to be popped from the stack.
Therefore, the system stack grows from higher toward lower memory locations.
The SP register can be updated via any instruction capable of modifying an 16-bit SFR.
Note: Due to the internal instruction pipeline, a stack pointer initialization stalls the
instruction flow until the operation is finished. A POP and RETURN instruction can
immediately follow an instruction updating the SP.
SP
Stack Pointer
15
14
13
SFR
12
11
10
9
8
7
Reset Value: FC00H
6
5
4
3
2
0
SP
0
rwh
r
Field
Bits
Type Description
SP
[15:1]
rwh
Modifiable portion of register SP
Specifies the top of the system stack.
0
[0]
r
Fixed to 0
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The Stack Pointer Segment Register SPSEG
This non-bit addressable register selects the segment being used at run-time to access
system stack. The lower eight bits of register SPSEG select one of up 256 segments of
64-kilobytes each, while the higher 8 bits are reserved for future use.
SPSEG
Stack Pointer Segment
SFRb
7
Reset Value: 0000H
15
14
13
12
11
10
9
8
0
0
0
0
0
0
0
0
SPSEGNR
r
r
r
r
r
r
r
r
rw
Field
Bits
Type Description
SPSEGNR
[7:0]
rw
6
5
4
3
2
1
0
Stack Pointer Segment Number
Specifies the segment where the stack is located.
System stack addresses are generated by directly extending the 16-bit contents of the
SP register by the contents of the SPSG register as shown in Figure 2-20.
The system stack cannot cross a 64k byte segment boundary.
SPSEG
Stack Pointer Segment
255
254
1
0
15
7 SPSEGNR 0
15
0
SP
FF’0000H
FE’0000H
23
16 15
0
01’0000H
00’0000H
Figure 2-20 Addressing via the Stack Pointer
In case of a non-segmented memory mode, the SPSG register is also used to generate
the physical address. If a non-segmented memory model is selected, extreme care
should be taken when changing the contents of the SPSG register. Improper SPSG
change may result in erroneous system behavior. The SPSG register can be updated via
any instruction capable of modifying an SFR.
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Note: Due to the internal instruction pipeline, a write operation to the SPSG register
stalls the instruction flow until the SPSG register is really updated. The instruction
immediately following the instruction updating the SPSG register can use the new
value.
The Stack Overflow Pointer STKOV
This non-bit addressable STKOV register is compared with the SP register before each
implicit write operation which decrements the contents of the SP register. If the contents
of the SP register are equal to the contents of the STKOV register, a stack overflow trap
will occur.
STKOV
Stack Overflow Pointer
15
14
13
12
11
SFR
10
9
8
7
Reset Value: FA00H
6
5
4
3
2
1
0
STKOV
0
rw
r
Field
Bits
Type Description
STKOV
[15:1]
rw
Modifiable portion of register STKOV
Specifies the segment offset address of the lower
limit of the system stack.
0
[0]
r
Fixed to 0
The STKOV register can be updated via any instruction capable of modifying a SFR.
Note: The Stack Pointer Segment Register SPSG is not taken into account for the stack
pointer comparison. The system stack cannot cross a 64k segment.
This checking mechanism is triggered before every implicit write access. The contents
of the stack pointer is compared with the contents of the overflow register, whenever the
SP is to be decremented either by a CALLA, CALLI, CALLR, CALLS, PCALL, TRAP,
SCXT or PUSH instruction.
Note: If the Stack Pointer was explicitly changed as a result of move or arithmetic
instruction, SP is not compared to the contents of the STKOV. Therefore, if the
modified Stack Pointer is below the limit set by STKOV register, the stack violation
will not be detected. The stack overflow can be detected only if the contents of SP
are equal to (not less than) the contents of the STKOV and only in case of implicit
SP modification. This means that SP may be explicitly set to the value below
permitted SP range and even be operated there without triggering any traps.
However, if SP crosses the limit of the permitted SP range from outside the range
as a result of implicit change (PUSH for example), the event (SP) = (STKOV) will
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trigger the corresponding trap. Note that event (SP) = (STKOV) resulting from an
explicit SP modification does not trigger the trap.
The Stack Overflow Trap is triggered when (SP) = (STKOV) and if SP is to be implicitly
decremented. This trap may be used in two different ways:
• Fatal error indication treats the stack overflow as a system error and executes
associated trap service routine. Under these circumstances, data in the bottom of the
stack may have been overwritten by the status information stacked upon servicing the
stack overflow trap.
• Automatic system stack flushing allows the system stack to be used as a ’Stack
Cache’ for a bigger external user stack.
The Stack Underflow Pointer STKUN
This non-bit addressable register STKUN is compared with the SP register before each
implicit read operation that increments the contents of the SP register. If the contents of
the SP register are equal to the contents of the STKUN register, a stack underflow
hardware trap will occur.
STKUN
Stack Underflow Pointer
15
14
13
12
11
SFR
10
9
8
7
Reset Value: FC00H
6
5
4
3
2
1
0
STKUN
0
rw
r
Field
Bits
Type Description
STKUN
[15:1]
rw
Modifiable portion of register STKUN
Specifies the segment offset address of the upper
limit of the system stack.
0
[0]
r
Fixed to 0
The STKUN register can be updated via any instruction capable of modifying a SFR.
Note: The Stack Pointer Segment Register SPSG is not taken into account for the stack
pointer comparison. The system stack cannot cross a 64 k segment.
This checking mechanism is triggered before each implicit read access. The contents of
the stack pointer are compared to the contents of the underflow register, whenever the
SP will be incremented either by a RET, RETS, RETP, RETI or POP instruction.
Note: If the Stack Pointer was explicitly changed as a result of move or arithmetic
instruction, SP is not compared to the contents of the STKUN register. Therefore,
if the modified Stack Pointer is above the limit set by STKUN register, the stack
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violation will not be detected. The stack underflow can be detected only if the
contents of SP are equal to (not higher than) the contents of the STKUN and only
in case of implicit SP modification. This means that SP may be explicitly set to the
value above the permitted SP range and even be operated there without triggering
any traps. However, if SP crosses the limit of the permitted SP range from outside
the range as a result of an implicit change (POP instruction, for example), the
event (SP) = (STKUN) will trigger the corresponding trap. Note that event (SP) =
(STKUN) resulting from an explicit SP modification does not trigger the trap.
The Stack Underflow Trap is triggered when (SP) = (STKUN) and if SP is to be implicitly
incremented. This trap may be used in two different ways:
Fatal error indication treats the stack underflow as a system error and executes
associated trap service routine.
• Automatic system stack refilling allows use of the system stack as a ’Stack Cache’
for a bigger external user stack.
Scope of Stack Limit Control
The stack limit control implemented by the register pair STKOV and STKUN detects
cases in which the Stack Pointer (SP) crosses the defined stack area as a result of
implicit change.
Note: If a stack overflow or underflow event occurs in an ATOMIC/EXT sequence, the
stack operations that are part of the sequence are completed. The trap is issued
after the completion of the entire ATOMIC/EXT sequence.
2.6
Data Processing
All standard arithmetic, shift and logical operations are performed in the 16-bit ALU. In
addition to the standard arithmetic and logic unit, the ALU of the C166S V2 CPU includes
bit manipulation, multiply and divide unit. Most internal execution blocks have been
optimized to perform operations on either 8-bit or 16-bit numbers. After the pipeline has
been filled, most instructions are completed in one CPU cycle. The status flags are
automatically updated in the PSW register after each ALU operation (see Section 2.6.6).
These flags allow branching upon specific conditions. Support of both signed and
unsigned arithmetic is provided by the user selectable branch test. The status flags are
also preserved automatically by the CPU upon entry into an interrupt or trap routine.
2.6.1
Data Types
The C166S V2 CPU supports operations on booleans/bits, bit strings, characters,
integers, and signed fraction numbers. Most instructions operate with specific data
types, while others are useful for manipulating several data types.
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The C166S V2 CPU data formats are able to support all ANSI C data types. Additional
to the ANSI C data types, some C-Compilers support new types that allow efficient use
of the bit manipulation instructions in embedded control applications.. .
Table 2-10
ANSI C Data Types
ANSI C Data Types
Size (bytes) Range
CPU Data Format
bit
1 bit
0 or 1
BIT
sfrbit
1 bit
0 or 1
BIT
esfrbit
1 bit
0 or 1
BIT
signed char
1
-128 to +127
BYTE
unsigned char
1
0 to 255U
BYTE
sfr
1
0 to 65535U
WORD
esfr
1
0 to 65535U
WORD
signed short
2
-32768 to 32767
WORD
unsigned short
2
0 to 65535U
WORD
bitword
2
0 to 65535U
WORD or BIT
signed int
2
-32768 to 32767
WORD
unsigned int
2
0 to 65535U
WORD
signed long
4
-2147483648 to
+2147483647
Not directly supported
unsigned long
4
0 to 4294967295UL Not directly supported
float
4
+/-1,176E-38 to
+/-3,402E+38
Not directly supported
double
8
+/- 2,225E-308 to
+/- 1,797E+308
Not directly supported
long double
8
+/- 2,225E-308 to
+/- 1,797E+308
Not directly supported
near pointer
2
16/14 bits
depending on
memory model
WORD
far pointer
4
14 bits (16 k) in any Not directly supported
page
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Table 2-11
CPU Data Formats
CPU Data Format
Size (bytes) Range
BIT
1 bit
0 or 1
BYTE
1
0 to 255U or -128 to +127
WORD
2
0 to 65535U or -32768 to 32767
2.6.2
Constants
In addition to the powerful addressing modes, the C166S V2 CPU instruction set also
supports the use of wordwide or bytewide immediate constants. For optimum utilization
of the available code storage, these constants are represented in the instruction formats
by either 3, 4, 8, or 16 bits. The short constants are always zero-extended, while the long
constants are truncated if necessary, to match the data format required for the particular
operation (see table below): .
Table 2-12
Constant Formats
Mnemonic
Word Operation
Byte Operation
#data3
0000H + data3
00H + data3
#data4
0000H + data4
00H + data4
#data8
0000H + data8
data8
#data16
data16
data16 ∧ FFH
#mask
0000H + mask
mask
Note: Immediate constants are always signified by a leading sign ’#’.
2.6.3
16-bit Adder/Subtracter, Barrel Shifter, and 16-bit Logic Unit
All standard arithmetic and logical operations are performed by the 16-bit ALU. In case
of byte operations, signals from bits 6 and 7 of the ALU result are used to control the
condition flags. Multiple precision arithmetic is supported by a “CARRY-IN” signal to the
ALU from previously calculated portions of the desired operation.
A 16-bit barrel shifter provides multiple bit shifts in a single cycle. Rotations and
arithmetic shifts are also supported.
2.6.4
Bit Manipulation Unit
C166S V2 CPU offers a large number of instructions for bit processing. The special bit
manipulation unit was implemented for this purpose. The bit manipulation instructions
enable efficient control and testing of peripherals. Unlike other microcontrollers,
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C166S V2 CPU features instructions that provide direct access to two operands in the
bit addressable space without requiring them to be moved to temporary locations.
The same logical instructions that are available for words and bytes can also be used for
bits. The user can compare and modify a control bit for a peripheral in one instruction.
Multiple bit shift instructions have been included to avoid long instruction streams of
single bit shift operations. These instruction require a single CPU cycle. Additionally, bit
field instructions enable are able to modify the multiple bits in one operand in a single
instruction.
All instructions that manipulate single bits or bit groups internally use a read-modify-write
sequence that accesses the whole word containing the specified bit(s).
This method has several consequences:
• Bits can be modified only within the internal address areas, i.e. internal RAM and
SFRs. External locations cannot be used with bit instructions.
The upper 256 bytes of the SFR area, the ESFR area, and the internal RAM are bit
addressable, i.e. those register bits located within the respective sections can be directly
manipulated using bit instructions. The other SFRs must be accessed byte/word wise.
Note: All GPRs are bit addressable independent of the allocation of the register bank via
the Context Pointer (CP). Even GPRs allocated to not bit addressable RAM
locations provide this feature.
• The read-modify-write approach may be critical with hardware-effected bits. In such
cases, the hardware may change specific bits while the read-modify-write operation is
in progress, where the write back would overwrite the new bit value generated by the
hardware. The solution is either the implemented hardware protection (see below) or
realized through special programming (see Section 4.1).
Protected bits are not changed during the read-modify-write sequence, that is, when
hardware sets something like an interrupt request flag between the read and the write of
the read-modify-write sequence. The hardware protection logic guarantees that only the
intended bit(s) is/are effected by the write-back operation.
Note: If a conflict occurs between a bit manipulation generated by hardware and an
intended software access, the software access has priority and determines the
final value of the respective bit.
2.6.5
Multiply and Divide Unit
The C166S V2 CPU multiply and divide unit has two separated parts. One is the fast
16x16-bit multiplier that executes a multiplication in one CPU cycle. The other one is a
division sub-unit which performs the division algorithm in 21 CPU cycles maximum.
According to the data and division types, the division length varies between 18 and 21
cycles. The divide instruction requires four CPU cycles to be executed. For performance
reasons, the rest of the division algorithm runs in the background during the following
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seventeen CPU cycles, while further instructions are executed in parallel. If another
instruction tries to use the unit while a division is still running, the execution of this new
instruction is stalled until the division is finished.
Interrupt tasks can also be started and executed immediately without any delay. The
previous division will be finished in the background. If an instruction of the interrupt task
uses the multiply and divide unit before the previous division process is finished, the
instruction flow will be stalled as well. To avoid these stalls, the multiply and division unit
should not be used during the first fourteen CPU cycles of the interrupt tasks. This
requires up to fourteen one-cycle instructions to be executed between the interrupt entry
and the first instruction which uses the multiply and divide unit again (worst case).
The Multiply/Divide High Register MDH
The sixteen bit, non-bit addressable MDH register contains the high word of the 32-bit
multiply/divide MD register used by the CPU when it performs a multiplication or a
division using implicit addressing (DIV, DIVL, DIVLU, DIVU, MUL, MULU). After an
implicitly addressed multiplication, this register represents the high order sixteen bits of
the 32-bit result. For long divisions, the MDH register must be loaded with the high order
sixteen bits of the 32-bit dividend before the division has started. After any division, the
MDH register represents the 16-bit remainder.
MDH
Multiply Divide High Word
15
14
13
12
11
SFR
10
9
8
7
Reset Value: 0000H
6
5
4
3
2
1
0
MDH
rwh
Field
Bits
Type Description
MDH
[15:0]
rwh
High part of MD
The high order sixteen bits of the 32-bit multiply and
divide register MD.
Whenever this register is updated via software, the Multiply/Divide Register In Use
(MDRIU) flag in the Multiply/Divide Control register (MDC) is set to 1.
The Multiply/Divide Low Register MDL
The sixteen bit, non-bit addressable MDL register contains the low word of the 32-bit
multiply/divide MD register used by the CPU when it performs a multiplication or a
division using implicit addressing (DIV, DIVL, DIVLU, DIVU, MUL, MULU). After a
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multiplication, this register represents the low order sixteen bits of the 32-bit result. For
long divisions, the MDL register must be loaded with the low order sixteen bits of the
32-bit dividend before the division has started. After any division, the MDL register
represents the 16-bit quotient.
MDL
Multiply Divide Low Word
15
14
13
12
11
SFR
10
9
8
Reset Value: 0000H
7
6
5
4
3
2
1
0
MDL
rwh
Field
Bits
Type Description
MDL
[15:0]
rwh
Low part of MD
The low order 16 bits of the 32-bit multiply and
divide register MD.
Whenever this register is updated via software, the Multiply/Divide Register In Use
(MDRIU) flag in the Multiply/Divide Control register (MDC) is set to 1. The MDRIU flag is
cleared whenever the MDL register is read via software.
The Divide Control Register MDC
This bit addressable 16-bit register is implicitly used by the CPU when it performs a
division or multiplication in the ALU.
MDC
Multiply Divide Control
SFRb
Reset Value: 0000H
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
MDR
IU
0
0
0
0
r
r
r
r
r
r
r
r
r
r
r
rwh
r
r
r
r
Field
Bits
Type Description
MDRIU
[4]
rwh
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Multiply/Divide Register In Use
0:
Cleared when MDL is read via software.
1:
Set when MDL or MDH is written via
software, or when a multiply or divide
instruction is executed.
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The MDRIU flag is the only portion of the MDC register used for multiplication and
division within the C166S V2 CPU. This bit indicates the usage of the MDL and MDH
register. It must be stored prior to a new multiplication or division operation. The
remaining portions of the MDC register are never used by the dedicated multiplication
and division hardware.
2.6.6
The Processor Status Word PSW
This bit addressable register reflects the current status of the microcontroller. Two
groups of bits represent the current ALU status and the current CPU interrupt status.
Two separate bits (USR0 and USR1) within register PSW are provided as general
purpose flags.
PSW
Processor Status Word
15
14
13
12
SFRb
11
10
9
8
ILVL
IEN
HLD
EN
BANK
rwh
rw
rw
rwh
Reset Value: 0000H
7
4
3
2
1
0
USR USR MUL
1
0
IP
E
Z
V
C
N
rwh
rwh
rwh
rwh
rwh
rwh
rwh
6
5
r
Field
Bits
ILVL
[15:12] rwh
CPU Priority Level
0H
Lowest Priority
...
...
Highest Priority
FH
IEN
[11]
rw
Interrupt/PEC Enable Bit (globally)
0
Interrupt/PEC requests are disabled
1
Interrupt/PEC requests are enabled
HLDEN
[10]
rw
Hold Enable
0
external bus arbitration disabled
1
external bus arbitration enabled
BANK
[9:8]
rwh
Reserved for Register File Bank Selection
00
Global register bank
01
Reserved
10
Local register bank 1
11
Local register bank 2
USR1
[7]
rwh
General Purpose Flag
May be used by application
USR0
[6]
rwh
General Purpose Flag
May be used by application
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Field
Bits
Type Description
MULIP
[5]
r
Multiplication/Division in progress
Always set to 0
E
[4]
rwh
End of Table Flag
0
Source operand is neither 8000h nor 80h
1
Source operand is 8000h or 80h
Z
[3]
rwh
Zero Flag
0
ALU result is not zero
1
ALU result is zero
V
[2]
rwh
Overflow Flag
0
No Overflow produced
0
Overflow produced
C
[1]
rwh
Carry Flag
0
No carry/borrow bit produced
1
Carry/borrow bit produced
N
[0]
rwh
Negative Result
0
ALU result is not negative
1
ALU result is negative
ALU Status (N, C, V, Z, E, MULIP)
The condition flags (N, C, V, Z, E) within the PSW indicate the ALU status resulting from
the last performed ALU operation. They are set by the majority of instructions according
to the specific rules depending on the ALU operation or data movement.
After execution of an instruction which explicitly updates the PSW register, the condition
flags may no longer represent an actual CPU status. An explicit write operation to the
PSW register supersedes the condition flag values implicitly generated by the CPU. An
explicit read access to the PSW register returns the value of the PSW register after
execution of the immediately preceding instruction.
Note: After reset, all of the ALU status bits are cleared.
• N-Flag: For the majority of ALU operations, the N-flag is set to 1, if the most significant
bit of the result contains a 1; otherwise, it is cleared. In the case of integer operations,
the N-flag can be interpreted as the sign bit of the result (negative: N = 1, positive: N
= 0). Negative numbers are always represented as the 2s complement of the
corresponding positive number. The range of signed numbers extends from '–8000H'
to '+7FFFH' for the word data type, or from '–80H' to '+7FH' for the byte data type. For
Boolean bit operations with only one operand, the N-flag represents the previous state
of the specified bit. For Boolean bit operations with two operands, the N-flag
represents the logical XORing of the two specified bits.
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• C-Flag: After an addition, the C-flag indicates that a “Carry” from the most significant
bit of the specified word or byte data type has been generated. After a subtraction or
a comparison, the C-flag indicates a “Borrow” which represents the logical negation of
a “Carry” for the addition.
This means that the C-flag is set to 1, if no carry from the most significant bit of the
specified word or byte data type has been generated during a subtraction. Subtraction
is performed by the ALU as a 2s complement addition. The C-flag is cleared when this
complement addition causes a “Carry”.
The C-flag is always cleared for logical, multiply and divide ALU operations, because
these operations cannot cause a “Carry” flag to be set.
For shift and rotate operations, the C-flag represents the value of the bit shifted out
last. If a shift count of zero is specified, the C-flag will be cleared. The C-flag is also
cleared for a Prioritize operation, because a 1 is never shifted out of the MSB during
the normalization of an operand.
For Boolean bit operations with only one operand, the C-flag is always cleared. For
Boolean bit operations with two operands, the C-flag represents the logical ANDing of
the two specified bits.
•
V-Flag: The addition, subtraction and 2's complement operations set the V-flag to '1'
if the result exceeds the range of 16 bit signed numbers for word operations ('–8000H'
to '+7FFFH'), or 8 bit signed numbers for byte operations ('–80H' to '+7FH'). Otherwise,
the V-flag is cleared. Note, that the result of an integer addition, integer subtraction,
or 2's complement is not valid if the V-flag indicates an arithmetic overflow.
For multiplication and division the V-flag is set to 1 if the result can not be represented
in a word data type, otherwise it is cleared. Note that a division by zero will always
cause an overflow. Unlike the division result, the result of multiplication is valid
regardless of V-flag value.
Since the logical ALU operations cannot produce an invalid result, the V-flag is cleared
by these operations.
The V-flag is also used as 'Sticky Bit' for rotate right and shift right operations. Using
only the C-flag, a rounding error caused by a shift right operation can be estimated as
up to one half of the LSB of the result. In conjunction with the V-flag, the C-flag allows
evaluation of the rounding error with a finer resolution (see table below).
For Boolean bit operations with only one operand, the V-flag is always cleared. For
Boolean bit operations with two operands, the V-flag represents the logical ORing of
the two specified bits.
Shift Right Rounding Error Evaluation
• Z-Flag: The Z-flag is normally set to 1 if the result of an ALU operation equals zero;
otherwise, it is cleared.
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C-Flag
V-Flag
0
0
1
1
0
1
0
1
Rounding Error Quantity
0<
No rounding error
Rounding error
Rounding error
Rounding error
<
=
>
1
/2 LSB
/2 LSB
1
/2 LSB
1
For addition and subtraction with “Carry”, the Z-flag is only set to 1 if the Z-flag already
contains a 1 as a result from previous operation and the result of the current ALU
operation also equals zero. This mechanism supports the multiple precision
calculations.
For Boolean bit operations with only one operand, the Z-flag represents the logical
negation of the previous state of the specified bit. For Boolean bit operations with two
operands, the Z-flag represents the logical NORing of the two specified bits. For the
Prioritize operation, the Z-flag indicates whether the second operand was zero or not.
• E-Flag: End of table flag. The E-flag can be altered by the instructions which perform
ALU or data movement operations. The E-flag is cleared by those instructions that
cannot be reasonably used for table search operations. In all other cases, the E-flag
value depends on the value of the source operand to signify whether the end of a
search table is reached or not. If the value of the source operand of an instruction
equals the lowest negative number which depends on the data format of the
corresponding instruction ('8000H' for the word data type, or '80H' for the byte data
type), the E-flag is set to 1; otherwise, it is cleared.
• MULIP-Flag: The MULIP-flag always sticks to 0.
Note: The MULIP flag is a part of the C166 task environment. For compatibility reasons,
the bit is still implemented even if not used. A multiply and divide ALU operation
of the C166S V2 CPU is no longer interruptible.
• BANK: The BANK bitfield of the PSW registers indicates which one of the three
physical register banks is activated. The BANK field is updated by hardware upon
entry into an interrupt service routine, but it can be also modified by software. The
BANK field can be changed explicitly by any instruction which can write to the PSW.
Also, it is implicitly updated by the RETI instruction.
• HLDEN: Refer to EBC Chapter 6.4.1.
CPU Interrupt Status (IEN, ILVL)
The Interrupt Enable bit allows global enable (IEN=1) or disable (IEN=0) of interrupts.
The 4-bit Interrupt Level field (ILVL) specifies the priority of the current CPU activity. The
interrupt level is updated by hardware upon entry into an interrupt service routine, but it
can also be modified via software to prevent other interrupts from being acknowledged.
In case an interrupt level '15' has been assigned to the CPU, it has the highest possible
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priority, and thus the current CPU operation cannot be interrupted except by hardware
traps or external non-maskable interrupts. For details please, refer to Section 5
“Interrupt and Trap Functions”.
After reset, all interrupts are globally disabled and the lowest priority (ILVL=0) is
assigned to the initial CPU activity.
2.7
Parallel Data Processing
The new CoXXX arithmetic instructions are performed in the MAC unit. The MAC unit
provides single instruction-cycle, non-pipelined, 32-bit additions; 32-bit subtraction; right
and left shifts; 16-bit by 16-bit multiplication; and multiplication with cumultative
subtraction/addition. The MAC unit includes the following major components, shown in
Figure 2-21:
•
•
•
•
•
•
•
•
16-bit by 16-bit signed/unsigned multiplier with signed result1)
Concatenation Unit
Scaler (one-bit left shifter) for fractional computing
40-bit Adder/Subtracter
40-bit Signed Accumulator
Data Limiter
Accumulator Shifter
Repeat Counter
1)
The same hardware-multiplier is used in the ALU.
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16-bit input operands
Repeat Counter
MCW Register
Concatenation
Unit
signed/unsigned
Multiplier
Signed
Ext.
40-bit Adder/Subtracter
ACCU-Shifter
Round+Saturation
40-bit Signed Accumulator
MSW Register
16-bit
32-bit
Limiter
40-bit
Figure 2-21 Functional MAC Unit Block Diagram
The working register of the MAC Unit is a dedicated 40-bit wide Accumulator register. A
set of consistent flags is automatically updated in the MSW register (see Section 2.7.10)
after each MAC operation. These flags allow branching on specific conditions. Unlike the
PSW flags, these flags are not preserved automatically by the CPU upon entry into an
interrupt or trap routine. All dedicated MAC registers must be saved on the stack if the
MAC unit is shared between different tasks and interrupts.
2.7.1
Representation of Numbers and Rounding
The C166S V2 CPU supports the 2s complement representation of binary numbers. In
this format, the sign bit is the MSB of the binary word. This is set to zero for positive
numbers and set to one for negative numbers. Unsigned numbers are supported only by
multiply/multiply-accumulate instructions which specify whether each operand is signed
or unsigned.
In 2s complement fractional format, the N-bit operand is represented using the 1.[N-1]
format (1 signed bit, N-1 fractional bits). Such a format can represent numbers between
-1 and +1-2-[N-1]. This format is supported when MP of MCW is set.
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The C166S V2 CPU implements 2s complement rounding’. With this rounding type, one
is added to the bit to the right of the rounding point (bit 15 of MAL), before truncation
(MAL is cleared).
2.7.2
The 16-bit by 16-bit signed/unsigned Multiplier and Scaler
The multiplier executes 16-bit by 16-bit parallel signed/unsigned fractional and integer
multiplication in one CPU-cycle. The multiplier allows the multiplication of unsigned and
signed operands. The result is always presented in a signed fractional or integer format.
The result of the multiplication feeds a one-bit Scaler to allow compensation for the extra
sign bit gained in multiplying two 16-bit 2s complement numbers.
2.7.3
Concatenation Unit
The Concatenation Unit enables the MAC unit to perform 32-bit arithmetic operations in
one CPU cycle. The Concatenation Unit concatenates two 16-bit operands to a 32-bit
operand before the 32-bit arithmetic operation is executed in the 40-bit adder/subtracter.
The second required operand is always the current Accumulator contents. The
Concatenation Unit is also used to pre-load the Accumulator with a 32-bit value.
2.7.4
One-bit Scaler
The One-bit scaler can shift the result of the concatenation unit or the output of the
multiplier one bit to the left. The scaler is controlled by the executed instruction for the
concatenation or by the MP control bit.
The product is shifted one bit to the left to compensate for the extra sign bit gained in
multiplying two 16-bit 2s complement numbers. The enabled automatic shift is performed
only if both input operands are signed.
MCW
MAC Control Word
SFRb
Reset Value: 0000H
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
MP
MS
0
0
0
0
0
0
0
0
0
r
r
r
r
r
rw
rw
r
r
r
r
r
r
r
r
r
Field
Bits
Type Description
MP
[10]
rw
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One-bit scaler control
0
Multiplier product shift disabled
1
Multiplier product shift enabled
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• MP-Control Bit: If the MP mode bit is set and both multiplier operands are signed
types, the multiplier output is automatically shifted left by one bit. In the case of a
multiply and accumulate operation, the output of the multiplier is shifted before being
added to the accumulator.
2.7.5
The 40-bit Adder/Subtracter
The 40-bit adder/Subtracter allows intermediate overflows in a series of multiply/
accumulate operations. The adder/Subtracter has two input ports. The 40-bit port is the
feedback of the Accumulator output through the ACCU-Shifter to the Adder/Subtracter.
The 32-bit port is the input port for the operand coming from the One-bit Scaler. The
32-bit operands are signed and extended to 40-bits before the addition/subtraction is
performed.
The output of the Adder/Subtracter goes to the Accumulator. It is also possible to round
the result and to saturate it on a 32-bit value automatically after every accumulation. The
round operation is performed by adding 00’00008000H to the result. Automatic
saturation is enabled by setting the saturation bit, the MAC Control Word (MCW).
MCW
MAC Control Word
SFRb
Reset Value: 0000H
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
MP
MS
0
0
0
0
0
0
0
0
0
r
r
r
r
r
rw
rw
r
r
r
r
r
r
r
r
r
Field
Bits
Type Description
MS
[9]
rw
Saturation control
0
Saturation disabled
1
Saturation enabled
• MS-Control Bit: If the MS mode bit is set, the accumulator will be automatically
saturated to 32-bits. The MAC Unit supports signed saturation.
When the accumulator is in the overflow saturation mode and an overflow occurs, the
accumulator is loaded with either the most positive or the most negative value
representable in a 32-bit value, depending on the direction of the overflow as well as the
arithmetic used. The value of the accumulator upon saturation is 00’7fff’ffffh (positive) or
ff’8000’0000h (negative).
2.7.6
The Data Limiter
Saturation arithmetic is also provided to selectively limit overflow when reading the
accumulator by means of a CoSTORE <destination>., MAS instruction. Limiting is
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performed on the MAC-Unit accumulator. If the contents of the Accumulator can be
represented in the destination operand size without overflow, then the data limiter is
disabled and the operand is not modified. If the contents of the accumulator cannot be
represented without overflow in the destination operand size, the limiter will substitute a
“limited” data as explained in the next table:
Table 2-13
Limiter Output
ME-flag
MN-flag
Output of Limiter
0
x
unchanged
1
0
7FFFH
1
1
8000H
Notice that in this particular case, both the accumulator and the status register are not
affected. MAS is readable by means of a CoSTORE instruction only.
2.7.7
The Accumulator Shifter
The accumulator shifter is a parallel shifter with a 40-bit input and a 40 bit output. The
source accumulator shifting operation are:
• No shift (Unmodified)
• Up to 16-bit Arithmetic Left Shift
• Up to 16-bit Arithmetic Right Shift
Notice that the ME, MSV, and MSL bits from MSW are affected by left shifts; therefore,
if the saturation mechanism is enabled (MS), the behavior is similar to the one of the
Adder/Subtracter.
Note: Certain precautions are required in case of left shift with saturation enabled.
Generally, if MAE contains significant bits, then the 32-bit value in the accumulator
is to be saturated. However, it is possible that left shift may move some significant
bits out of the Accumulator. The 40-bit result will be misinterpreted and will be
either not saturated or saturated incorrectly. There is a chance that the result of
left shift may produce a result which can saturate an original positive number to
the minimum negative value, or vice versa.
2.7.8
The 40-bit Signed Accumulator Register
The 40-bit Accumulator consists of three smaller registers, MAH, MAL, and MAE. MAH
and MAL are 16 bits wide; MAE is 8 bits wide. MAE is the Most Significant Byte of the
40-bit accumulator. This byte performs a guarding function. MAE is accessed as the
Least Significant Byte of MSW.
When MAH is written, the value in the accumulator is automatically adjusted to signed
extended 40-bit format. That means MAE will be automatically loaded by zeros for the
positive number (MAH has 0 in the most significant bit). In the case of the negative
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number (MAH has 1 in the most significant bit), the MAE will be loaded with ones,
representing the extended 40-bit negative number in 2s compliment notation. One may
see that the extended 40-bit value is equal to 32-bit value without extension. In other
words, after this extension, MAE does not contain significant bits. Generally, this
condition is present when the highest 9 bits of the 40-bit signed result are the same.
During the accumulator operations, an overflow may happen and the result may not fit
into 32-bits and the MAE will change. The extension flag “E”, which is the part of the most
significant byte of MSW, is set when the signed result in the accumulator has overflowed
the 32-bit boundary. This condition is present when the highest 9 bits of the 40-bit signed
result are not the same, i.e. MAE contains significant bits.
Most CoXXX operations specify the 40-bit accumulator register as a source and/or a
destination operand.
The MAC Unit Accumulator Extension Byte MAE
The MAE register is a part of the 40-bit MAC unit accumulator register. MAE is accessed
as the Least Significant Byte of MSW. It is implicitly used by the MAC unit for MAC
operation. In case a word operand is written into MAH, the MAE register becomes signextended. It can be accessed via any instruction capable of accessing an SFR.
MSW
MAC Status Word
15
14
0
r
13
8
MV MSL ME MSV MC
MZ
MN
MAE
rwh
rwh
rwh
rwh
rwh
11
rwh
10
rwh
7
Reset Value: 0000H
9
rwh
12
SFRb
Field
Bits
Type Description
MAE
[7:0]
rwh
6
5
4
3
2
1
0
The most significant bits of the 40-bit Accumulator
The MAC Unit Accumulator High Word MAH
The MAH register is a part of the 40-bit MAC unit accumulator register. It is implicitly used
by the MAC unit for MAC operation. In case the word operand is written into MAH, MAL
acquires the zero value and the MAE register becomes sign-extended. It can be
accessed via any instruction capable of accessing an SFR.
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MAH
Accumulator High Word
15
14
13
12
11
SFR
10
9
8
7
Reset Value: 0000H
6
5
4
3
2
1
0
MAH
rwh
Field
Bits
Type Description
MAH
[15:0]
rwh
High part of Accumulator
The middle (bits 31 to 16) word of the 40-bit MAC
Accumulator.
The MAC Unit Accumulator Low Word MAL
The MAL register is a part of the 40-bit MAC unit accumulator register. It is implicitly used
by the MAC Unit for MAC operation. In case of explicit write access to MAH, MAL
receives a zero value. It can be accessed via any instruction capable of accessing an
SFR.
MAL
Accumulator Low Word
15
14
13
12
11
SFR
10
9
8
7
Reset Value: 0000H
6
5
4
3
2
1
0
MAL
rwh
Field
Bits
Type Description
MAL
[15:0]
rwh
2.7.9
Low part of Accumulator
The low order 16 bits of the 40-bit MAC
Accumulator.
The Repeat Counter MRW
The Repeat Counter MRW controls the number of repetitions a loop must be executed.
The register must be pre-loaded before it can be used with -USRx CoXXX operations.
MAC operations are able to decrement this counter. When an -USRx CoXXX instruction
is executed, the MRW is checked on the zero value before the MRW is decremented. If
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the MRW equals zero, the USRx bit is set and MRW is not further decremented. The
MRW can be accessed via any instruction capable of accessing a SFR.
MRW
MAC Repeat Word
15
14
13
12
SFRb
11
10
9
8
7
Reset Value: 0000H
6
5
4
3
2
1
0
REPEAT COUNT
rwh
Field
Bits
Type Description
REPEAT COUNT
[15:0]
rwh
16-bit loop counter
All CoXXX instructions have a 3-bit wide repeat control field ’rrr’ in the operand field to
control the MRW repeat counter. It is located within CoXXX instructions at bit positions
[31:29].
–
–
–
–
–
‘000’
‘001’
‘010’
‘011’
’1xx’
->
->
->
->
->
regular CoXXX instruction.
RESERVED
‘- USR0 CoXXX’ instruction, decrements repeat counter.
‘- USR1 CoXXX’ instruction, decrements repeat counter.
RESERVED.
The following example shows a loop which is executed 20 times. Every time the
CoMACM instruction is executed, the MRW counter is decremented.
loop01:
- USR1
mov
MRW, #19
CoMACM
ADD
JMPA
[IDX0+], [R0+]
R2,#2
cc_nusr1, loop01
Because correctly predicted JMPA is executed in 0-cycle, it offers the functionality of a
repeat instruction.
Note: The USR0 bit should be used carefully because this bit was pre-existing and,
therefore, may have been used by programmer or compiler.
2.7.10
The MAC Unit Status Word MSW
The MSW bit addressable register shows the current MAC Unit state. Two groups of bits
represent the current MAC Unit status and the eight additional extension bits belonging
to the MAC accumulator.
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MAC Unit Status (MV, MN, MZ, MC, MSV, ME, MSL)
The condition flags (MV, MN, MZ, MC, MSV, ME, MSL) within the MSW indicate the
MAC resulting from the most recently performed MAC operation. These flags are
controlled by the majority of the MAC instructions according to specific rules. Those rules
depend on the instruction managing the MAC or data movement operation.
After execution of an instruction which explicitly updates the MSW register, the condition
flags may no longer represent an actual MAC status. An explicit write operation to the
MSW register supersedes the condition flag values implicitly generated by the MAC unit.
An explicit read access to the MSW register returns the value of the MSW register after
execution of the immediately preceding instruction. The MSW register can be accessed
via any instruction capable of accessing an SFR.
Note: After reset, all MAC status bits are cleared.
MSW
MAC Status Word
15
14
0
r
13
8
MV MSL ME MSV MC
MZ
MN
MAE
rwh
rwh
rwh
rwh
rwh
11
rwh
10
rwh
7
Reset Value: 0000H
9
rwh
12
SFRb
6
5
4
3
2
1
0
Field
Bits
Type Description
MAE
[7:0]
rwh
The most significant bits of the 40-bit Accumulator
MN
[8]
rwh
Negative Result
0
MAC result is positive
1
MAC result is negative
MZ
[9]
rwh
Zero Flag
0
MAC result is not zero
1
MAC result is zero
MC
[10]
rwh
Carry Flag
0
No carry/borrow produced
1
Carry/borrow produced
MSV
[11]
rwh
Sticky Overflow Flag
0
No Overflow occurred
1
Overflow occurred
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Field
Bits
Type Description
ME
[12]
rwh
MAC Extension Flag
0
MAE does not contain significant bits
1
MAE contains significant bits
MSL
[13]
rwh
Sticky Limit Flag
0
Result was not saturated
1
Result was saturated
MV
[14]
rwh
Overflow Flag
0
No Overflow produced
1
Overflow produced
• Accu Extension MAE: These 8 bits are part of the 40-bit accumulator register. The
MAC Unit implicitly uses these bits during a MAC operation. When writing to the MAH,
the MAE is automatically signed extended with the most significant bit of the MAH
register.
• MN-Flag: For the majority of the MAC operations, the MN-flag is set to 1 if the most
significant bit of the result contains a 1; otherwise, it is cleared. In the case of integer
operations, the MN-flag can be interpreted as the sign bit of the result (negative:
MN=1, positive: MN=0). Negative numbers are always represented as the 2s
complement of the corresponding positive number. The range of signed numbers
extends from '8000000000H' to '7FFFFFFFFFH'.
• MZ-Flag: The MZ-flag is normally set to 1 if the result of a MAC operation equals zero;
otherwise, it is cleared.
• MC-Flag: After a MAC addition, the MC-flag indicates that a “Carry” from the most
significant bit of the accumulator extension MAE has been generated. After a MAC
subtraction or a MAC comparison, the MC-flag indicates a “Borrow” representing the
logical negation of a “Carry” for the addition. This means that the MC-flag is set to 1,
if no “Carry” from the most significant bit of the Accumulator has been generated
during a subtraction. Subtraction is performed by the MAC Unit as a 2s complement
addition and the MC-flag is cleared when this complement addition caused a “Carry”.
For left shift MAC operations, the MC-flag represents the value of the bit shifted out
last. Right shift MAC operations always clear the MC-flag. The arithmetic right shift
MAC operation can set the MC-flag if the enabled round operation generates a “Carry”
from the most significant bit of the Accumulator extension MAE.
• MSV-Flag: The addition, subtraction, 2s complement, and round operations always
set the MSV-flag to 1 if the MAC result overflows the maximum range of 40-bit signed
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numbers. If the MSV-flag indicates an arithmetic overflow, the MAC result of an
operation is not valid. The MSV-flag is a ’Sticky Bit’. Once set, other MAC operations
cannot affect the status of the MSV-flag. Only a direct write operation can clear the
MSV-flag.
• ME-Flag: The ME-flag is set if the accumulator extension MAE contains significant
bits. The ME-flag is set if the nine highest accumulator bits are not all equal.
• MSL-Flag: The MSL-flag is set if an automatic saturation of the accumulator has
happened. The automatic saturation is enabled if the MS-bit of the MAC Control Word
register MCW is set. The MSL-Flag can be also set by instructions which limit the
contents of the accumulator. If the accumulator has been limited, the MSL-Flag is set.
The MSL-Flag is a 'Sticky Bit'. Once set, it cannot be affected by the other MAC
operations. Only a direct write operation can clear the MSL-flag.
• MV-Flag: The addition, subtraction, and accumulation operations set the MV-flag to 1
if the result exceeds the maximum range of signed numbers (80’00000000H to
7F’FFFFFFFFH); otherwise, the MV-flag is cleared. Note that if the MV-flag indicates
an arithmetic overflow, the result of the integer addition, integer subtraction, or
accumulation is not valid.
2.7.11
The MAC Unit Control Word MCW
This bit addressable register controls the operation of the MAC Unit. It can be accessed
via any instruction capable of addressing an SFR.
MCW
MAC Control Word
SFRb
Reset Value: 0000H
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
MP
MS
0
0
0
0
0
0
0
0
0
r
r
r
r
r
rw
rw
r
r
r
r
r
r
r
r
r
Field
Bits
Type Description
MP
[10]
rw
One-bit scaler control
0
Multiplier product shift disabled
1
Multiplier product shift enabled
MS
[9]
rw
Saturation control
0
Saturation disabled
1
Saturation enabled
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• MS-Control Bit: If the MS mode bit is set, the accumulator will be automatically
saturated to 32 bits. The MAC Unit supports signed saturation.
• MP-Control Bit: If the MP mode bit is set and both multiplier operands are of signed
types, the multiplier output is automatically shifted left by one bit. In the case of a
multiply and accumulate operation, the output of the multiplier is shifted before being
added to the accumulator.
2.8
Dedicated CSFRs
The Constant Zeros Register ZEROS
All bits of this bit addressable register are fixed to 0 by hardware. This register is readonly. Register ZEROS can be used as a register-addressable constant of all zeros for bit
manipulation or mask generation. It can be accessed via any instruction which is capable
of accessing an SFR.
ZEROS
Constant Zeros Register
SFRb
Reset Value: 0000H
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
r
r
r
r
r
r
r
r
r
r
r
r
r
r
r
r
Field
Bits
Type Description
0
[all]
r
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The Constant Ones Register ONES
All bits of this bit addressable register are fixed to 1 by hardware. This register is readonly. Register ONES can be used as a register-addressable constant of all ones for bit
manipulation or mask generation. It can be accessed via any instruction capable of
accessing an SFR.
ONES
Constant Ones Register
SFRb
Reset Value: FFFFH
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
r
r
r
r
r
r
r
r
r
r
r
r
r
r
r
r
Field
Bits
Type Description
1
[all]
r
Fixed to One
CPU Identification Register CPUID
This 16-bit register contains the module and revision number of the implemented
C166S V2 core module.
CPUID
CPU Identification Register
15
14
13
12
11
ESFR
10
9
8
7
Reset Value: 03??H
6
5
4
3
2
MODULE NUMBER
VERSION NUMBER
r
r
Field
Bits
Type Description
MODULE NUMBER
[15:8]
r
Module Number
03H C166S V2 core module number
r
Version Number
Version Number
VERSION NUMBER [7:0]
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3
C166S V2 Memory Organization
The memory space of the C166S V2 CPU is configured in a “Von Neumann”
architecture. This means that code and data are accessed within the same linear
address space. All of the physically separated memory areas, including internal ROM/
Flash/DRAM (if integrated into a specific derivative), internal RAM, internal Special
Function Register Areas (SFRs and ESFRs), and external memory are mapped into a
single common address space.
The C166S V2 CPU provides a total addressable memory space of 16 MBytes. This
address space is arranged as 256 segments of 64 KBytes each. Each segment is again
subdivided into four data pages of 16 KBytes each (see Figure 3-1).
Most internal memory areas are mirrored into the system segment, segment 0. The
upper 4 KBytes of segment 0 (00’F000H...00’FFFFH) hold the Special Function Register
Areas (SFR and ESFR) and the DPRAM areas.
Data may be stored in any part of the internal memory areas. Code may be stored in any
part of the internal memory areas except the SFR blocks, the DPRAM, and Internal
SRAM and internal IO area as these areas may be used for control/data, but not for
instructions.
The 64 KByte memory area of segment 191 (BF’0000H...BF’FFFFH) cannot be used to
store code and data. It is reserved for “on chip” boot and debug/monitor program
memories.
Accesses to internal memory areas on devices without the appropriate internal
memories will produce unpredictable results.
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int. program memory
4MByte
C166S V2 Memory Organization
FF´FFFFH
Segment
255
Data Page 1023
FF´0000H
C0´0000H
00’FFFFH
BF´0000H
ext. memory
8MByte
Segment
191
reserved
Data Page 3
41´0000H
Segment
64
RAM /
SFR
internal-IO
Area
00’C000H
ext. IO
2MByte
Data Page 2
21´0000H
Internal
SRAM
Segment
32
00’8000H
20´0000H
ext. memory
~2 MByte
03´0000H
Data Page 1
Segment
2
02´0000H
External
Memory
Segment
1
Segment
0
01´0000H
Data Page 3
00’4000H
Data Page 0
...
Data Page 0
00´0000H
System Segment 0
64KByte
16MByte
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00’E000H
Internal
SRAM
40´0000H
Figure 3-1
00’F000H
00´0000H
Memory Areas and Address Space
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3.1
Data Organization in Memory
Bytes are stored at even or odd byte addresses. Words are stored in ascending memory
locations with the low byte at an even byte address followed by the high byte at the next
odd byte address. Instruction double words are stored in ascending memory locations
as two subsequent words, without any restrictions (non aligned). Single bits are always
stored in the specified bit position at a word address. The memory and registers store
data and instructions in little endian byte order (the least significant bytes are at lower
addresses) The byte ordering is illustrated in Figure 3-2. Bit position 0 is the least
significant bit of the byte at an even byte address, and bit position 15 is the most
significant bit of the byte at the next odd byte address. Bit addressing is supported for a
part of the Special Function Registers, a part of the internal RAM, and for the General
Purpose Registers.
º
xxxx’xxxAH
1 1 ... Bits ...
8
xxxx’xxx9H
7 6 ... Bits ...
0
xxxx’xxx8H
Byte
xxxx’xxx7H
Byte
xxxx’xxx6H
Word (High Byte)
xxxx’xxx5H
Word (Low Byte)
xxxx’xxx4H
Double Word (High)
xxxx’xxx3H
Double Word (Third)
xxxx’xxx2H
Double Word (Second)
xxxx’xxx1H
Double Word (Low Byte)
xxxx’xxx0H
º
Figure 3-2
xxxx’xxxFH
Storage of Words, Bytes and Bits in a Byte Organized Memory
Note: Byte units forming a single word must always be stored within the same physical
(internal, external, ROM, RAM) and organizational (page, segment) memory area.
3.2
Internal Program Memory
The C166S V2 CPU reserves an address area of 4 MBytes for Internal Program
Memory. The internal memory can be ROM, SRAM, Flash or DRAM. Devices with
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Internal Program Memory expand the Internal Program Memory area from the beginning
of segment 192, i.e. starting at address C0’0000H.
The Internal Program Memory can be used for both code (instructions) and data
(constants, tables, etc.) storage.
Code fetches are always made on even word addresses. The highest possible code
storage location in the Internal Program Memory is either xx’xxFEH for single word
instructions, or xx’xxFCH, for double word instructions.
Any word and byte data read access may use the indirect or long 16-bit addressing mode.
There is no short addressing mode for Internal Program Memory operands. Any word
data access is made to an even byte address. Any double word access is made to a
modulo 4 address (even word address). The highest possible word data storage location
in the Internal Program Memory is xxxx’xxFEH, the highest double word location
xxxx’xxFCH.
The Internal Program Memory is not provided for single bit storage, and therefore is not
bit addressable.
Note: The ‘x’ in the locations above depend on the available Internal Program Memory.
3.3
DPRAM, Internal SRAM, and SFR Areas
The C166S V2 CPU differentiates between various internal memory types and internal
peripheral areas. These data memories and the IO/SFR areas are located within data
page 3 and provide fast accesses using one dedicated Data Page Pointer (see Figure 33).
Note: Code access is not possible from the DPRAM, the Internal RAM, or the IO/SFR
areas.
3.3.1
Data Memories
Two dedicated volatile memories are available for data storage:
• The DPRAM can be used for:
– General Purpose Register Banks (GPRs)
– Variable and other data storage, especially for MAC operands
– System Stack (not recommended if Internal SRAM is integrated)
• The Internal SRAM can be used for:
– Variable and other data storage
– System Stack (recommended if Internal SRAM is integrated)
A 3 kByte memory area (00‘F200H...000’FE00H) is reserved for the DPRAM. The upper
256 Bytes of the DPRAM (00’FD00H...00’FDFFH) and the GPRs of the current bank are
provided for single bit storage, and thus are bit addressable (see shaded blocks in
Figure 3-3). Any word or byte data in the DPRAM can be accessed via indirect or long
16-bit addressing modes, if the selected DPP register points to data page 3. Any word
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data access is made on an even byte address. The highest possible word data storage
location in the DPRAM is 0000’FDFEH.
A 24 kByte memory area (00‘8000H...000’DFFFH) is reserved for the Internal SRAM. Any
word and byte data in the Internal SRAM can be accessed via indirect or long 16-bit
addressing modes, if the selected DPP register points to data page 3 or data page 2. Any
word data access is made on an even byte address. The highest possible word data
storage location in the Internal SRAM is 0000’DFFEH.
RAM/SFR
Area
Data Page 3
IO
Area
00’FFFFH
00’FFFFH
SFR
Area
00’F000H
internal
IO
00’E000H
00’FE00H
DPRAM
Intenal
SRAM
00’FD00H
00’C000H
Data Page 2
Intenal
SRAM
00’8000H
DPRAM
Data Page 1
External
Memory
00’4000H
00’F200H
Data Page 0
ESFR
Area
System Segment 0
64KByte
Figure 3-3
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00’F000H
00´0000H
RAM and SFR Areas
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3.3.2
Special Function Register Areas
The functions of the CPU, the bus interface, the IO ports, and the on-chip peripherals of
the C166S V2 device are controlled via a number of so-called Special Function
Registers (SFRs). These SFRs are arranged within two areas of 512 Bytes each. The
first register block, the SFR area, is located in the 512 Bytes above the DPRAM
(00’FE00H...00’FFFFH). The second register block, the Extended SFR (ESFR) area, is
located in the 512 Bytes below the DPRAM (00’F000H...00’F1FFH).
Special Function Registers can be addressed via indirect and long 16-bit addressing
modes. Using an 8-bit offset together with an implicit base address allows word SFRs
and their respective low bytes to be addressed. However, this does not work for the
respective high bytes!
Note: High byte access of SFRs using the 8-bit offset addressing mode is not possible.
Note: Writing to any byte of an SFR causes the non-addressed complementary byte to
be cleared!
Note: GPRs can be accessed using the 8-bit offset addressing mode, but they are not
mapped into the SFR and ESFR memory area. an internal peripheral bus access
is executed using the respective long address instead of a GPR access.
The upper half of each register block (except the 16 highest words, refer to Section 2.5.1
) is bit-addressable, so the respective control/status bits can be directly modified or
checked using bit addressing.
When accessing registers in the ESFR area using 8-bit addresses or direct bit
addressing, the Extend Register (EXTR) instruction is required to switch the short
addressing mechanism from the standard SFR area to the Extended SFR area before
accessing registers in the ESFR area. This is not required for 16-bit and indirect
addresses. GPRs R15...R0 are duplicated, i.e. they are accessible within both register
blocks via short 2-, 4- or 8-bit addresses without switching.
Example:
EXTR
MOV
BFLDL
BSET
MOV
;------MOV
User Manual
#4
;Switch to ESFR area for the next four instructions
ODP2, #data16
;ODP2 (ESFR register) uses 8-bit register addressing
DP6, #mask, #data8;DP6 (ESFR register) bit addressing for bit fields
DP6.7
;DP6 (ESFR register) bit addressing for single bits
T8REL, R1
;T8REL uses 16-bit address, R1 is duplicatedº
;...and also accessible via the ESFR mode
;(EXTR is not required for this access)
;------------------;The scope of the EXTR #4 instruction ends here!
T8REL, R1
;T8REL uses 16-bit address, R1 is duplicatedº
;...and does not require switching
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To minimize the switching of SFR banks, the ESFR area contains registers that are
mainly required for initialization and mode selection. Registers that need to be accessed
frequently are allocated to the standard SFR area wherever possible.
Note: The tools are equipped to monitor accesses to the ESFR area and will
automatically insert EXTR instructions, switch the SFR bank address, or issue a
warning in case of missing or excessive EXTR instructions.
3.3.3
IO Area
Some parts of the C166S V2 CPU memory area are marked as IO. These memory areas
have the following special properties:
– Accesses are not buffered and cached
The write back buffers and caches of the C166S V2 CPU are not used to store IO
read and write accesses.
– Special handling of destructive reads
The pipeline of the C166S V2 CPU allows speculative reads. Memory locations of
the IO area are not read until all speculations are solved. Destructive read accesses
are delayed.
– Write before read execution
The pipeline length of the C166S V2 CPU enables a read instruction to read a
memory location before a preceding write instruction has executed its write access.
Data forwarding guarantees the correct instruction flow execution. In case of an IO
read access, the read access will be delayed until all IO writes pending in the
pipeline are executed. In case of a write access, peripherals will change their
internal states. Write accesses must actually be executed before the next read
access is initiated.
Note: The bit manipulation instructions (BSET, BCLR...) use the read-modify-write
approach. The IO read access of this instructions will be stalled until all IO write
accesses are finished.
The following memory areas are marked as IO:
– 2 Mbytes of external IO located to 20’0000H to 3F’FFFFH
– SFR and ESFR areas located from 00’FE00H to 00’FFFFH and from 00’F000H to
00’F1FFH respectively
– 4 kByte internal IO located from 00’E000H to 00’EFFFH
Note: All external IO areas support real byte accesses. All internal IO areas do not
support real byte transfers. For more details on the exception of (E)SFR areas
refer to Section 3.3.2.
3.3.4
PEC Source and Destination Pointers
The source and destination pointers for data transfers on the PEC channels are located
in the 4-kByte internal IO area. Each channel uses a pair of pointers stored in two
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subsequent word registers, with the source pointer (SRCPx) on the lower and the
destination pointer (DSTPx) on the higher word address (x = channel number). The PEC
registers are part of the PEC itself and are addressed via the internal peripheral bus.
In contrast to the C166 family, the pointers are not located in the internal RAM. The
pointers are located in the 4 kByte internal IO.
If a PEC channel is not used, the corresponding pointer locations are not available and
cannot be used for word and byte storage.
Writing to any byte of the PEC pointers does cause the non-addressed complementary
byte to be cleared!
For more detail about use of the source and destination pointers for PEC data transfer,
see the “Interrupt and Exception Execution” section.
3.4
External Memory Space
The C166S V2 CPU is capable of using an address space of up to 16 MBytes. Only
portions of this address space are occupied by internal memory areas. All addresses not
used for on-chip memory or for registers may reference external memory locations. This
external memory is accessed via the external bus interface. This interface may further
limit the amount of addressable external memory.
External word and byte data can be accessed only via indirect or long 16-bit addressing
modes using one of the four DPP registers. There is no short addressing mode for
external operands. Any word data access is made to an even byte address and double
word accesses to modulo 4 byte addresses (even word address).
The external memory is not provided for single bit storage and therefore is not bit
addressable.
3.4.1
Boot and Debug/Monitor Program Memories
The 64 KByte memory area of segment 191 (BF’0000H...BF’FFFFH) is reserved for boot
and debug/monitor program memories. These “on chip” memories are accessed using
the EBC and are a part of the EBC‘s external memory space. Accesses are not visible
at the port pins of the EBC even if these memories are part of the external memory
space. During normal code execution, this segment is not accessible for the C166S V2
CPU. In case of a read access, the EBC will deliver the predefined 0000H value and write
access will not be executed. Only in special boot and emulation modes can the
memories of segment 191 be accessed.
Note: Segment 191 (BF’0000H...BF’FFFFH) is not usable for the system application.
External memories and peripherals located in this segment will never be
accessed.
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3.5
Crossing Memory Boundaries
The address space of the C166S V2 CPU is implicitly divided into logical memory areas
and equally sized blocks of different granularity. Crossing the boundaries between these
areas or blocks (code or data) requires special attention to ensure that the controller
executes the desired operations.
Memory Areas are partitions of the address space that represent different kinds of
memory (if provided at all). These memory areas are the internal RAM areas, the internal
IO areas, the internal Program Memories (if available), and the external memory.
Accessing subsequent data locations that belong to different memory areas is not fully
supported and may therefore lead to erroneous results. There is no problem if the
memory boundaries are word aligned. However, when executing code, the different
memory areas (Internal Program Memory areas and external memory) must be switched
explicitly via branch instructions. Sequential boundary crossing is not supported and may
leads to erroneous results.
Segments are contiguous blocks of 64 KBytes each. They are referenced via the Code
Segment Pointer (CSP) for code fetches and via an explicit segment number for data
accesses overriding the standard DPP scheme.
During code fetching, segments are not changed automatically, but rather must be
switched explicitly. The instructions JMPS, CALLS, and RETS will do this. Larger
sequential programs make sure that the highest used code location of a segment
contains an unconditional branch instruction to the respective following segment, to
prevent the prefetcher from trying to leave the current segment.
Data Pages are contiguous blocks of 16 KBytes each. They are referenced via the data
page pointers DPP3...0 and via an explicit data page number for data accesses
overriding the standard DPP scheme. Each DPP register can select one of the possible
1024 data pages. The DPP register that is used for the current access is selected via the
two upper bits of the 16-bit data address. Subsequent 16-bit data addresses that cross
the 16 KByte data page boundaries will use different data page pointers, while the
physical locations need not be subsequent within memory.
3.6
System Stack
The system stack may be defined within the internal RAM, but can be also located
externally. The size of the system stack is limited to 64 kBytes and must be located in
one segment. For all system stack operations, the stack memory is accessed via a 24 bit
stack pointer. The Stack Pointer register (SP) represents the low order 16 bits of the
24 bit stack pointer, also referred to as Stack Pointer Offset. The Stack Segment Pointer
(SPSEG) represents the high order 8 bits of the stack pointer, also referred to as Stack
Segment.
The system stack implementation in the C166S V2 CPU is from high to low memory. The
system stack grows downward as it is filled. The SP register is decremented first each
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time data is pushed on the system stack, and incremented after each time the data is
pulled from the system stack. Only word accesses are supported to the system stack.
The 24 bit stack pointer points to the address of the latest system stack entry, rather than
to the next available system stack address.
A stack overflow (STKOV) register and a Stack Underflow (STKUN) register are
provided to control the lower and upper limits of the selected stack area. These two stack
boundary registers can be used for protection against data destruction.
3.6.1
Data Organization in Global General Purpose Registers
The C166S V2 CPU differentiates between global memory mapped General Purpose
Register (GPR) banks and local not mapped GPR banks. In addition to the memory
mapped register banks, the C166S V2 CPU has two local not memory mapped GPR
register banks for very fast context switching (see Section 2.4).
Note: The local GPR banks are not memory mapped and the GPRs cannot be accessed
using a long or indirect memory address.
The C166S V2 CPU supports register bank (context) switching. Multiple global memory
mapped register banks can physically exist within the DPRAM at the same time;
however, only the global register bank selected by the Context Pointer register (CP) is
active at a given time. Selecting a new active global register bank is done by simply
updating the CP register.
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Mapping of the global General Purpose Registers to DPRAM Addresses is shown here:
DPRAM Address
Byte Registers
Word Register
<CP> + 1EH
---
R15
<CP> + 1CH
---
R14
<CP> + 1AH
---
R13
<CP> + 18H
---
R12
<CP> + 16H
---
R11
<CP> + 14H
---
R10
<CP> + 12H
---
R9
<CP> + 10H
---
R8
<CP> + 0EH
RH7RL7
R7
<CP> + 0CH
RH6RL6
R6
<CP> + 0AH
RH5RL5
R5
<CP> + 08H
RH4RL4
R4
<CP> + 06H
RH3RL3
R3
<CP> + 04H
RH2RL2
R2
<CP> + 02H
RH1RL1
R1
<CP> + 00H
RH0RL0
R0
A particular Switch Context (SCXT) instruction performs register bank switching and an
automatic save of the previous context. The number of implemented register banks
(arbitrary sizes) is limited only by the size of the available DPRAM.
The memory mapped GPRs use a block of sixteen consecutive words within DPRAM
Segment 0. The Context Pointer (CP) register determines the base address of the
currently active register bank. This register bank may consist of up to sixteen word GPRs
(R0, R1, .. R15), and/or of up to sixteen byte GPRs (RL0, RH0, º, RL7, RH7). The sixteen
byte GPRs are mapped onto the first eight word GPRs (see table above).
In contrast to the system stack, a register bank grows from lower towards higher address
locations and occupies a maximum space of 32 bytes. The GPRs are accessed via short
2-, 4- or 8-bit addressing modes using the Context Pointer (CP) register as base address
(independent of the current DPP register contents). Additionally, each bit in the currently
active register bank can be accessed individually.
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4
Instruction Pipeline
The pipeline of the C166S V2 CPU has seven stages. Each stage processes its
individual task. The first two stages form the instruction fetch pipeline and the remaining
five stages constitute the instruction processing pipeline. The instruction fetch pipeline is
used to pre-fetch instructions and to store them into an instruction FIFO. The
preprocessing of branch instructions in combination with the instruction FIFO allows
filling of the execution pipeline with a continuous flow of instructions. In the case of an
incorrectly predicted instruction flow, the instruction fetch pipeline is bypassed to reduce
the number of dead cycles. All instructions must pass through each of the five stages of
the instruction processing pipeline regardless of the need of some stages to complete
an execution of certain instructions. The following illustrates the pipeline stages
operation.
1st -> PREFETCH:
This stage pre-fetches instructions from the PMU in the predicted order. The instructions
are pre-processed in the branch detection unit to detect branches. The prediction logic
decides if the branches are assumed to be taken or not.
2st -> FETCH:
The instruction pointer of the next instruction to be fetched is calculated according to the
branch prediction rules. For zero-cycle branch execution, the Branch Folding Unit preprocesses and combines detected branches with the preceding instructions. Pre-fetched
instructions are stored in the instruction FIFO. At the same time, instructions are
transported out of the instruction FIFO to be executed in the instruction processing
pipeline.
3st -> DECODE:
The instructions are decoded and, if required, the register file is accessed to read the
GPR used in indirect addressing modes.
4st -> ADDRESS:
All the operand addresses are calculated. The SP register is de/incremented for all
instructions which implicitly access the system stack.
5st -> MEMORY:
All the required operands are fetched.
6st -> EXECUTE:
An ALU or MAC-Unit operation is performed on the previously fetched operands. The
Condition flags are updated. All explicit write operations to CPU-SFR registers and all
auto-in/decrement operations of GPRs used as indirect address pointers are performed.
7st -> WRITE BACK:
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All external operands and the remaining operands within the internal DPRAM space are
written back. Operands located in the internal SRAM are buffered in the Write Back
Buffer.
There are C166S V2 CPU-specific so-called injected instructions. These instructions are
generated internally by the machine to provide the time needed to process instructions
requiring more than one CPU cycle for processing. They are automatically injected into
the decode stage of the pipeline, then they pass through the remaining stages like every
standard instruction. Program interrupt, PEC transfer, and OCE operations are also
performed by means of injected instructions. Although these internally injected
instructions will not be noticed in reality, they are introduced here to ease the explanation
of the pipeline operation.
Because up to five different instructions are processed simultaneously, additional
hardware has been dedicated in the C166S V2 CPU to deal with dependencies which
may exist between instructions in different pipeline stages. This extra hardware supports
’forwarding’ of the operand read and write values and resolves most of the possible
conflicts—such as multiple usage of buses—in a time optimized way without
performance loss. This makes the pipeline unnoticeable for the user in most cases.
However, there are some rare cases in which the C166S V2 CPU pipeline requires
attention by the programmer. In these cases, the delays caused by the pipeline conflicts
can be used for other instructions to optimize performance.
Note: The C166S V2 CPU has a fully interlocked pipeline. Instruction re-ordering is only
required for performance reasons.
The following examples describe the pipeline behavior in special cases and give
principle rules to improve the performance by re-ordering the execution of instructions.
4.1
Instruction Dependencies in Different Pipeline Stages
Bandwidth limitations and data dependencies between instructions can dramatically
decrease the performance of CPUs. The C166S V2 CPU has dedicated hardware to
detect and to resolve different kind of dependencies. Some of those dependencies are
described in the following section.
4.1.1
The General Purpose Registers
The GPRs are the working registers of the C166S V2 CPU and there are a lot of possible
dependencies between instructions using GPRs. A high speed five port register file
prevents bandwidth conflicts. The dedicated hardware is implemented to detect and
resolve the data dependencies. Special forwarding busses are used to forward GPR
values from one pipeline stage to another. This allows the execution of instructions
without any delay despite of data dependencies.
In
In+1
ADD
ADD
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In+2
In+3
In+4
ADD
R6,R0
ADD
R6,R1
......
.
Tn
Tn+1
Tn+2
Tn+3
Tn+4
Tn+5
DECODE
In=
ADD R0,R1
In+1=
ADD R3,R0
In+2=
ADD R6,R0
In+3=
ADD R6,R1
In+4
In+5
ADDRESS
In-1
In=
ADD R0,R1
In+1=
ADD R3,R0
In+2=
ADD R6,R0
In+3=
ADD R6,R1
In+4
MEMORY
In-2
In-1
In=
ADD R0,R1
In+1=
ADD R3,R0
In+2=
ADD R6,R0
In+3=
ADD R6,R1
EXECUTE
In-3
In-2
In-1
In=
ADD R0,R1
In+1=
ADD R3,R0
In+2=
ADD R6,R0
WRITE BACK
In-4
In-3
In-2
In-1
In=
ADD R0,R1
In+1=
ADD R3,R0
Only in the case in which a GPR is updated in the ALU and then directly used in one of
the following instructions as an address pointer will the detection unit force the pipeline
to stall. None of the instructions using indirect addressing modes are capable of
using a GPR, which is to be updated by one of the two immediately preceding
instructions. The new value of the GPR is calculated in the execute stage, while the
instruction using an indirect addressing mode accesses the GPR already in the Decode
Stage. The instruction is stalled in the address stage until the operation in the ALU is
executed and the result is forwarded to the address stage.
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In-1
In
In+1
In+2
In+3
In+4
........
ADD
R0,R1
MOV
R3,[R0]
ADD
R6,R0
ADD
R6,R1
........
Tn
Tn+1
Tn+2
Tn+3
Tn+4
Tn+5
DECODE
In=
ADD R0,R1
In+1=
MOV R3,[R0]
In+2
In+2
In+2
In+3
ADDRESS
In-1
In=
ADD R0,R1
In+1=
MOV R3,[R0]
In+1=
MOV R3,[R0]
In+1=
MOV R3,[R0]
In+2
MEMORY
In-2
In-1
In=
ADD R0,R1
EXECUTE
In-3
In-2
In-1
In=
ADD R0,R1
WRITE BACK
In-4
In-3
In-2
In-1
In+1=
MOV R3,[R0]
In=
ADD R0,R1
To avoid stalls, one multicycle or two single cycle instructions may be inserted. These
instructions must not update the GPR used for indirect addressing.
In-1
In
In+1
In+2
In+3
In+4
........
ADD
R0,R1
ADD
R6,R0
ADD
R6,R1
MOV
R3,[R0]
........
Tn
Tn+1
Tn+2
Tn+3
Tn+4
Tn+5
DECODE
In=
ADD R0,R1
In+1=
ADD R6,R0
In+2=
ADD R6,R1
In+3=
MOV R3,[R0]
In+4
In+5
ADDRESS
In-1
In=
ADD R0,R1
In+1=
ADD R6,R0
In+2=
ADD R6,R1
In+3=
MOV R3,[R0]
In+4
MEMORY
In-2
In-1
In=
ADD R0,R1
In+1=
ADD R6,R0
In+2=
ADD R6,R1
In+3=
MOV R3,[R0]
EXECUTE
In-3
In-2
In-1
In=
ADD R0,R1
In+1=
ADD R6,R0
In+2=
ADD R6,R1
WRITE BACK
In-4
In-3
In-2
In-1
In=
ADD R0,R1
In+1=
ADD R6,R0
4.1.2
Indirect Addressing Modes
In the case of read accesses using indirect addressing modes, the Address Generation
Unit uses a speculative addressing mechanism. The read data path to one of the
different memory areas (DPRAM, Internal SRAM, etc.) is selected according to a history
table before the address is decoded. This history table has one entry for each of the
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GPRs. The entries store the information of the last accessed memory area using the
corresponding GPR. In the case of an incorrect prediction of the memory area, the read
access must be restarted.
It is recommended that the GPR used for indirect addressing point to the same memory
area. If an updated GPR points to a different memory area, the next read operation will
access the wrong memory area. The read access must be repeated, which leads to
pipeline stalls.
In-1........
ADD
R3,[R0] , points to DPRAM
In
In+1 MOV
R0,R4
.....
Ii
MOV
DPPX,... ,change DPPx
.....
Im
ADD
R6,[R0] , points to SRAM
R6,R1
Im+1 ADD
Im+2 ........
Tn
Tn+1
Tn+2
Tn+3
Tn+4
Tn+5
DECODE
In=
MOV R3,[R0]
In+1=
MOV R0,R4
In+2
In+3
In+4
In+5
ADDRESS
In-1
In=
MOV R3,[R0]
In+1=
MOV R0,R4
In+2
In+3
In+4
MEMORY
In-2
In-1
In=
MOV R3,[R0]
In+1=
MOV R0,R4
In+2
In+3
EXECUTE
In-3
In-2
In-1
In=
MOV R3,[R0]
In+1=
MOV R0,R4
In+2
WRITE BACK
In-4
In-3
In-2
In-1
In=
MOV R3,[R0]
In+1=
MOV R0,R4
Tm
Tm+1
Tm+2
Tn+3
Tn+4
Tn+5
DECODE
Im=
MOV R6,[R0]
Im+1=
ADD R6,R1
Im+1=
ADD R6,R1
Im+2
Im+3
Im+4
ADDRESS
Im-1
Im=
MOV R6,[R0]
Im=
MOV R6,[R0]
Im+1=
ADD R6,R1
Im+2
Im+3
MEMORY
Im-2
Im-1
Im=
MOV R6,[R0]
Im+1=
ADD R6,R1
Im+2
EXECUTE
Im-3
Im-2
Im-1
Im=
MOV R6,[R0]
Im+1=
ADD R6,R1
WRITE BACK
Im-4
Im-3
Im-2
4.1.3
Im-1
Im=
MOV R6,[R0]
Memory Bandwidth Conflicts
Memory bandwidth conflicts can occur if instructions in the pipeline access the same
memory area at the same time. Special access mechanisms are implemented in the
C166S V2 CPU to minimize conflicts. The internal DPRAM of the C166S V2 CPU has
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two independent read/write ports; this allows parallel read and write operation without
delays. Write accesses to the internal SRAM can be buffered in a Write BACK Buffer until
read accesses are finished.
• Bandwidth conflicts in the DPRAM Area
All instructions except the CoXXX instructions can read only one memory operand per
cycle. A conflict between the read and one write access cannot occur because the
DPRAM has two independent read/write ports.
In-1
In
In+1
In+2
In+3
In+4
........
ADD
op1,R1
ADD
R6,R0
ADD
R6,op2
MOV
R3,[R0]
........
Tn
Tn+1
Tn+2
Tn+3
Tn+4
Tn+5
DECODE
In=
ADD op1,R1
In+1=
ADD R6,R0
In+2=
ADD R6,op2
In+3=
MOV R3,[R0]
In+4
In+5
ADDRESS
In-1
In=
ADD op1,R1
In+1=
ADD R6,R0
In+2=
ADD R6,op2
In+3=
MOV R3,[R0]
In+4
MEMORY
In-2
In-1
In=
ADD op1,R1
In+1=
ADD R6,R0
In+2=
ADD R6,op2
In+3=
MOV R3,[R0]
EXECUTE
In-3
In-2
In-1
In=
ADD op1,R1
In+1=
ADD R6,R0
In+2=
ADD R6,op2
WRITE BACK
In-4
In-3
In-2
In-1
In=
ADD op1,R1
In+1=
ADD R6,R0
Note: Only other pipeline stall conditions can generate a DPRAM bandwidth conflict.
The DPRAM is a synchronous pipelined memory. The read access starts with the
valid addresses on the address stage. The data are delivered in the Memory
stage. If a memory read access is stalled in the Memory stage and the following
instruction on the Address stage tries to start a memory read, the new read access
must be delayed as well. But, this conflict is hidden by an already existing stall of
the pipeline.
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• Bandwidth conflicts in the DPRAM Area
The CoXXX instructions are the only instructions able to read two memory operands
per cycle. A conflict between the two read and one pending write access can
occur if all three operands are located in the DPRAM areas. This is especially
important for performance in the case of executing a filter routine. One of the operands
should be located in the internal SRAM to guarantee a single cycle execution time of
the CoXXX instructions.
In-1
In
In+1
In+2
In+3
In+4
........
ADD
op1,R1
ADD
R6,R0
CoMAC [IDX0],[R0]
MOV
R3,[R0]
.......
.
Tn
Tn+1
Tn+2
Tn+3
Tn+4
Tn+5
DECODE
In=
ADD op1,R1
In+1=
ADD R6,R0
In+2=
CoMAC .....
In+3=
MOV R3,[R0]
In+4
In+4
ADDRESS
In-1
In=
ADD op1,R1
In+1=
ADD R6,R0
In+2=
CoMAC .....
In+3=
MOV R3,[R0]
In+3=
MOV R3,[R0]
MEMORY
In-2
In-1
In=
ADD op1,R1
In+1=
ADD R6,R0
In+2=
CoMAC .....
In+2=
CoMAC .....
EXECUTE
In-3
In-2
In-1
In=
ADD op1,R1
In+1=
ADD R6,R0
WRITE BACK
In-4
In-3
In-2
In-1
In=
ADD op1,R1
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• Internal SRAM
The internal SRAM is a single port memory with one read/write port. To reduce the
number of bandwidth conflict cases, a Write Back Buffer is implemented. It has three
entries for buffer data buffering. Only if the buffer is filled and a read and write
accesses occur at the same time, must the read access be stalled while one of
the buffer entries is written back.
In-1
In
In+1
In+2
In+3
In+4
........
ADD
op1,R1
ADD
R6,R0
ADD
R6,op2
MOV
R3,R2
.........
.
Tn
Tn+1
Tn+2
Tn+3
Tn+4
Tn+5
DECODE
In=
ADD op1,R1
In+1=
ADD R6,R0
In+2=
ADD R6,op2
In+3=
MOV R3,R2
In+4
In+4
ADDRESS
In-1
In=
ADD op1,R1
In+1=
ADD R6,R0
In+2=
ADD R6,op2
In+3=
MOV R3,R2
In+3=
MOV R3,R2
MEMORY
In-2
In-1
In=
ADD op1,R1
In+1=
ADD R6,R0
In+2=
ADD R6,op2
In+2=
ADD R6,op2
EXECUTE
In-3
In-2
In-1
In=
ADD op1,R1
In+1=
ADD R6,R0
WRITE BACK
In-4
In-3
In-2
In-1
In=
ADD op1,R1
In+1=
ADD R6,R0
Write Back
Buffer
full
full
full
full
full
full
4.1.4
CPU-SFRs and the Pipeline
CPU-SFRs control the CPU functionality and behavior. Changes and updates of CSFRs
influence the instruction flow in the pipeline. Therefore, special care is required to ensure
that instructions in the pipeline always work with the correct CSFRs values. CSFRs are
updated late on the Executed stage of the pipeline. Meanwhile, without conflict
detection, the instructions in the Decode, Address, and Memory stages would still
work without updated register values. The C166S V2 CPU detects conflict cases and
stalls the pipeline to guarantee a correct execution. For performance reasons, the CPU
differentiates between different classes of CPU-SFRs. The flow of instructions through
the pipeline can be improved by following the given rules used for instruction re-ordering.
There are three classes of CPU-SFRs:
• The harmless CSFRs (CPUID, ONES, ZEROS, MCW) do not generate pipeline
conflict cases. The MCW can be changed without stalling the pipeline. The MCW is
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updated in the Execute Stage and is not used for control purposes in the previous
stages. CPUID, ONES, and ZEROS are not changeable at all.
In-1
In
In+1
In+2
In+3
In+4
........
MOV
MCW,#16
ADD
R6,R0
ADD
R6,R1
MOV
R3,[R0]
........
Tn
Tn+1
Tn+2
Tn+3
Tn+4
Tn+5
In+2=
ADD R6,R1
In+3=
MOV R3,[R0]
In+4
In+5
In+2=
ADD R6,R1
In+3=
MOV R3,[R0]
In+4
In+2=
ADD R6,R1
In+3=
MOV R3,[R0]
DECODE
In=
In+1=
MOV MCW,#16 ADD R6,R0
ADDRESS
In-1
In=
In+1=
MOV MCW,#16 ADD R6,R0
MEMORY
In-2
In-1
In=
In+1=
MOV MCW,#16 ADD R6,R0
EXECUTE
In-3
In-2
In-1
In=
In+1=
MOV MCW,#16 ADD R6,R0
WRITE BACK
In-4
In-3
In-2
In-1
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ADD R6,R1
In=
In+1=
MOV MCW,#16 ADD R6,R0
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• The CSFR result registers MDH, MDL, MSW, MAH, MAL, MRW of the ALU and MACUnit are updated late in the Execute stage of the pipeline. If an instruction (except
CoSTORE) accesses explicitly these registers in the memory stage, the value cannot
be forwarded. The instruction must be stalled for one cycle on the Memory stage.
In-1
In
In+1
In+2
In+3
In+4
........
MUL
R0,R1
MOV
R6,MDL
ADD
R6,R1
MOV
R3,[R0]
........
Tn
Tn+1
Tn+2
Tn+3
Tn+4
Tn+5
DECODE
In=
MUL R0,R1
In+1=
MOV R6,MDL
In+2=
ADD R6,R1
In+3=
MOV R3,[R0]
In+3=
MOV R3,[R0]
In+4
ADDRESS
In-1
In=
MUL R0,R1
In+1=
MOV R6,MDL
In+2=
ADD R6,R1
In+2=
ADD R6,R1
In+3=
MOV R3,[R0]
MEMORY
In-2
In-1
In=
MUL R0,R1
In+1=
MOV R6,MDL
In+1=
MOV R6,MDL
In+2=
ADD R6,R1
EXECUTE
In-3
In-2
In-1
In=
MUL R0,R1
WRITE BACK
In-4
In-3
In-2
In-1
In+1=
MOV R6,MDL
In=
MUL R0,R1
By reordering instructions, the bubble in the pipeline can be filled with an instruction not
using this resource.
In-1
In
In+1
In+2
In+3
In+4
........
MUL
R0,R1
MOV
R3,[R0]
MOV
R6,MDL
ADD
R6,R1
........
Tn
Tn+1
Tn+2
Tn+3
Tn+4
Tn+5
DECODE
In=
MUL R0,R1
In+1=
MOV R3,[R0]
In+2=
MOV R6,MDL
In+3=
ADD R6,R1
In+4
In+5
ADDRESS
In-1
In=
MUL R0,R1
In+1=
MOV R3,[R0]
In+2=
MOV R6,MDL
In+3=
ADD R6,R1
In+4
MEMORY
In-2
In-1
In=
MUL R0,R1
In+1=
MOV R3,[R0]
In+2=
MOV R6,MDL
In+3=
ADD R6,R1
EXECUTE
In-3
In-2
In-1
In=
MUL R0,R1
In+1=
MOV R3,[R0]
In+2=
MOV R6,MDL
WRITE BACK
In-4
In-3
In-2
In-1
In=
MUL R0,R1
In+1=
MOV R3,[R0]
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• The third class are CSFRs which affect the whole CPU or the pipeline before the
Memory stage. The CPU-SFRs CPUCON1, CP, SP, STKUN, STKOV, VECSEG,
TFR, and PSW affect the overall CPU functioning while the C-SFRs IDX0, IDX1, QX1,
QX0, DPP0, DPP1, DPP2 and DPP3 only affect the Decode, Address, and Memory
stage when they are modified explicitly.
If this kind of CSFR has been modified, the pipeline behavior depends on the
instruction and addressing modes used to modify the CSFR.
– In the case of modification of these CSFRs by “POP CSFR” or by instructions using
the reg,#data16 addressing mode, a special mechanism is implemented to improve
performance during the initialization.
For further explanation, the instruction which modifies the CSFR can be called
“instruction_modify_CSFR”. This special case is detected in the Decode stage
when the instruction_modify_CSFR enters the processing pipeline. Further on,
instructions described in the following list are held in the decode stage. All other
instructions are not held.
- Instructions using long addressing mode (mem)
- Instructions using indirect addressing modes ([Rw], ]Rw+]......), except JMPI and
CALLI
- ENWDT, DISWDT, EINIT
- All CoXXX instructions
If the CPUCON1, CP, SP, STKUN, STKOV, VECSEG, TFR, or the PSW are
modified and the instruction_modify_CSFR reaches the execute stage, the pipeline
is canceled. The modification affects the entire pipeline and the instruction prefetch.
A clean cancel and restart mechanism is required to guarantee a correct instruction
flow. In case of modification of IDX0, IDX1, QX1, QX0, DPP0, DPP1, DPP2 or
DPP3 only the Decode, Address, and Memory stages are affected and the pipeline
must not be canceled. The modification does not affect the instructions in the
Address, Memory stage because they are not using this resource. Other kinds of
instructions are held in the Decode stage until the CSFR is modified.
The following example shows a case in which the pipeline is stalled. The instruction
MOV R6,R1 after the MOV IDX1,#12 instruction which modifies the CSFR will be
held in Decode Stage until the IDX1 register is updated. The next example shows
an optimized initialization routine.
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In-1
In
In+1
In+2
In+3
In+4
........
MOV
IDX1,#12
MOV
R6,mem
ADD
R6,R1
MOV
R3,[R0]
........
Tn
Tn+1
Tn+2
Tn+3
Tn+4
Tn+5
DECODE
In=
MOV IDX1,#12
In+1=
MOV R6,mem
In+1=
MOV R6,mem
In+1=
MOV R6,mem
In+1=
MOV R6,mem
In+2=
ADD R6,R1
ADDRESS
In-1
In=
MOV IDX1,#12
MEMORY
In-2
In-1
In=
MOV IDX1,#12
EXECUTE
In-3
In-2
In-1
In=
MOV IDX1,#12
WRITE BACK
In-4
In-3
In-2
In-1
In=
MOV IDX1,#12
Tn
Tn+1
Tn+2
Tn+3
Tn+4
Tn+5
DECODE
In=
MOV IDX1,#12
In+1=
MOV MAH,#23
In+2=
MOV MAL,#25
In+3=
MOV R3,#08
In+4
In+5
ADDRESS
In-1
In=
MOV IDX1,#12
In+1=
MOV MAH,#23
In+2=
MOV MAL,#25
In+3=
MOV R3,#08
In+4
MEMORY
In-2
In-1
In=
MOV IDX1,#12
In+1=
MOV MAH,#23
In+2=
MOV MAL,#25
In+3=
MOV R3,#08
EXECUTE
In-3
In-2
In-1
In=
MOV IDX1,#12
In+1=
MOV MAH,#23
In+2=
MOV MAL,#25
WRITE BACK
In-4
In-3
In-2
In-1
In=
MOV IDX1,#12
In+1=
MOV MAH,#23
In-1
In
In+1
In+2
In+3
In+4
In+1=
MOV R6,mem
........
MOV
IDX1,#12
MOV
MAH,#23
MOV
MAL,#25
MOV
R3,#08
........
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– For all the other instructions that modify this kind of CSFR, a simple stall and cancel
mechanism guarantees the correct instruction flow.
A possible explicit write-operation to this kind of CSFRs is detected on the Memory
stage of the pipeline. The following instructions on the Address and Decode Stage
are stalled. If the instruction reaches the execute stage, the entire pipeline and the
Instruction FIFO of the IFU are canceled. The instruction flow is completely restarted.
In-1
In
In+1
In+2
In+3
In+4
........
MOV
PSW,R4
MOV
R6,R1
ADD
R6,R1
MOV
R3,[R0]
........
Tn+1
Tn+2
Tn+3
DECODE
In+1=
MOV R6,R1
In+2=
ADD R6,R1
In+2=
ADD R6,R1
ADDRESS
In=
MOV PSW,R4
In+1=
MOV R6,R1
In+1=
MOV R6,R1
MEMORY
In-1
In=
MOV PSW,R4
EXECUTE
In-2
In-1
In=
MOV PSW,R4
WRITE BACK
In-3
In-2
In-1
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Tn+4
Tn+5
Tn+6
In+1=
MOV R6,R1
In=
MOV PSW,R4
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5
Interrupt and Exception Handling
The Interrupt and Exception Handler is responsible for managing all system and core
exceptions. Four kinds of exceptions are executed in a similar manner:
•
•
•
•
Interrupts generated by the Interrupt Controller ITC
DMA transfers issued by the Peripheral Event Controller PEC.
Software Traps caused by the TRAP instruction
Hardware Traps issued by faults or specific system states
Normal Interrupt Processing
The CPU temporarily suspends current program execution and branches to an interrupt
service routine to service a device requesting an interrupt. The current program status
(IP and PSW; in segmentation mode, also CSP) is saved in the internal system stack. A
prioritization scheme with sixteen priority levels specifies the order for handling multiple
interrupt requests.
Software and Hardware Traps
Trap functions are activated in response to special conditions that occur during the
execution of instructions. A trap can also be caused externally by the Non-Maskable
Interrupt pin, NMI. Several hardware trap functions are provided to handle erroneous
conditions and exceptions that arise during program execution. Hardware traps always
have the highest priority and cause immediate system response. The software trap
function is invoked by the TRAP instruction that generates a software interrupt for a
specified interrupt vector. For all types of traps, the current program status is saved in
the system stack.
Interrupt Processing via the Peripheral Event Controller (PEC)
A faster alternative to normal interrupt processing uses the C166S V2 CPU's integrated
Peripheral Event Controller (PEC) to service an interrupt requesting device. Triggered
by an interrupt request, the PEC performs a single word or byte data transfer between
any two memory locations. During a PEC transfer, the normal program execution of the
CPU is halted. No internal program status information needs to be saved. The same
prioritization scheme is used for PEC service as for normal interrupt processing.
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5.1
Interrupt System and Control
5.1.1
General Interrupt System Structure
The C166S V2 CPU can provide up to 128 separate interrupt nodes that may be
assigned to sixteen interrupt priority levels with four sub-priorities inside each level
(group priority) for up to 64 interrupt nodes or with eight sub-priorities inside each level
(group priority) in the case of more than 64 interrupt nodes. To support modular and
consistent software design techniques, most sources of an interrupt or PEC request are
supplied with separate interrupt control registers and interrupt vectors. The control
register contains an interrupt request flag, an interrupt enable bit, and an interrupt priority
of the associated source. Each source request is activated by one specific event,
determined by the selected operating mode of the requesting device. In some cases,
multi-source interrupt nodes are incorporated for efficient use of system resources.
These nodes can be activated by various source requests.
The C166S V2 CPU provides a vectored interrupt system. This system reserves specific
vector locations in the memory space for the reset, trap, and interrupt service functions.
Whenever a request occurs, the CPU branches to the location associated with the
respective interrupt source. The reserved vector locations build a jump table in the
address space of the C166S V2 CPU.
All pending interrupt requests are arbitrated. The arbitration winner is sent to the CPU
together with its priority level and action request. The CPU triggers the corresponding
action based on the required functionality (normal interrupt, PEC, jump table cache, etc.)
of the arbitration winner.
An action request will be accepted by the CPU if the requesting source has a higher
priority than the current CPU priority level and interrupts are globally enabled. If the
requesting source has a lower (or equal) interrupt level priority than the current CPU
task, it remains pending.
The basic functionality of the interrupt and peripheral event controller can be seen in
Figure 5-1:
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Interrupt and Peripheral Event Controller
Interrupt
Request
Lines
PEC Pointer
SRCP0
DSTP0
PECSEG0
SRCP1
DSTP1
PECSEG1
SRCP7
DSTP7
PECSEG7
irq0
irq1
C166S V2
CPU
irq2
irq3
Arbitration
PEC Request
Arbitr.
irq n-3
EOP
1)
irq n-2
irq n-1
Peripheral
Event
Controller
(PEC)
INT 2)
Arbitration
Control
PEC
Control
(Interrupt
Control
Registers)
(PEC
Control
Registers)
irq0IC
PECC0
irq1IC
PECC1
irq126IC
PECC7
EOPIC
PECISNC
Request
Request
Control
Control
Interrupt
Handler
(CPU Action
Request)
Interrupt
Interrupt
Request
Request
Interrupt
Handler
Control
Injection
Control
OCE
Injection
Request &
Control
Injection
Interface
Winner
OCE/
OCDS
Fast Bank
Switching
BNKSEL0
BNKSEL3
Interrupt Jump
Table Cache
FINT0CSP
FINT0ADDR
FINT1CSP
FINT1ADDR
1) number of interrupt nodes n (upto 128)
2) End of PEC Interrupt (EOPINT) is connected to interrupt request line irq n-1.
Therefore, only n-1 interrupt lines (irq n-2...0) are available for peripheral request
handling.
Figure 5-1
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5.1.2
Interrupt Arbitration
The C166S V2 interrupt arbitration system can handle interrupt requests from up to 128
sources. Interrupt requests may be triggered either by the C166S V2 peripherals or by
external inputs. The “End of PEC” interrupt for supporting enhanced PEC functionality is
connected internally to one interrupt request line.
The arbitration process starts with an enabled interrupt request and stays active as long
as an interrupt request is pending. If nothing is pending, the arbitration logic switches to
the idle state to save power.
Each interrupt request line is controlled by its interrupt control register xxIC (here and
below ‘xx’ stands for the mnemonic of the respective interrupt source). An interrupt
request event sets the interrupt request flag in the corresponding interrupt control
register (bit xxIC.xxIR). The interrupt request can also be triggered by the software if the
program sets the respective interrupt request bit. This feature is specifically used by
operating systems.
If the request bit has been set and the corresponding interrupt request is enabled by the
interrupt enable bit of the same control register (bit xxIC.xxIE), an arbitration cycle starts
with the next clock cycle. However, if an arbitration cycle is currently in progress, the new
interrupt request will be delayed until the next arbitration cycle. If an interrupt request (or
PEC request) is accepted by the core, the respective interrupt request flag is cleared
automatically.
All interrupt requests pending at the beginning of a new arbitration cycle are considered
simultaneously. Within the arbitration cycle, the arbitration is independent of the actual
request time.
C166S V2 uses a three-stage interrupt prioritization scheme for interrupt arbitration as
shown in Figure 5-2.
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Interrupt
Arbitration
Hardware
Traps
OCDS break
request
OCDS
or
OCE
Interrupt
Request
Lines
Request
Lines
Arbitration
xxxx (ILVL) +
x.xx (XGLVL)
PEC/
Interrupt
Handler
xxxxx
(OCDS service
request priority
level)
0xxxx
(ILVL
extended with
0 in MSB)
xxxxx
(request
priority level)
CPU
Action
Control
CPU
Arbitration
0xxxx
(ILVL. PSW
extended with
0 in MSB)
PSW
CPU
Stage 1:
Compared 4-bit ILVL+ 2/3-bit XGLVL
priority levels of interrupt sources
(64/128 priority levels)
Figure 5-2
Stage 2:
4-bit IRQ/PEC priority level
compared with
5-bit OCDS priority level
Stage 3:
5-bit request priority level
compared with
4-bit PSW priority level
Interrupt Arbitration
The first arbitration stage compares the priority levels of interrupt request lines. The
priority level of each requestor consists of interrupt priority level and group priority level.
An interrupt priority level is programmed for each interrupt request line by the 4-bit bit
field ILVL of the respective xxIC register. The group priority level is programmed for each
interrupt request line by the 2-bit bit field GLVL—and, in the case of more than 64
interrupt nodes, by the extension bit GPX of the register xxIC. GPX and GLVL combined
form the 3-bit (extended) group priority level XGLVL, controlling up to eight interrupt subpriorities within one of the sixteen interrupt levels.
Note: All interrupt request sources that are enabled and programmed to the same
interrupt priority level (ILVL) must have different group priority levels. Otherwise,
an incorrect interrupt vector may be generated.
The second arbitration stage compares the priority of the first stage winner with the
priority of OCDS service requests. C166S V2 OCDS service requests bypass the first
stage of arbitration and go directly to the CPU Action Control Unit. The CPU Action
Control Unit disregards the group priority level of interrupt/PEC requests and deals only
with interrupt priority levels (ILVL). For comparison with an OCDS service request priority
programmed with a 5-bit value, the 4-bit ILVL of the interrupt/PEC request is extended
to a 5-bit value with MSB=0. This means that any OCDS request with MSB=1 will always
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win the second stage arbitration. However, if there is a OCDS request with MSB=0
conflicting with the same priority interrupt/PEC request, the latter is sent to the CPU.
On the third arbitration stage, the priority level of the second stage winner is compared
with the priority of the current CPU task. An action request will be accepted by the CPU
if the requesting source has a priority level higher than the current CPU priority level (bits
ILVL of the PSW register) and for interrupt and PEC requests if they are globally enabled
by the global interrupt enable flag IEN in PSW. The CPU denies all interrupt/PEC
requests in case of a cleared IEN flag and an injection level between 0 to 15. To compare
with the 5-bit priority level of the second stage winner, the 4-bit ILVL.PSW is extended
to a 5-bit value with MSB=0. This means that any request with MSB=1 will always
interrupt the current CPU task. If the requester has a priority level lower than or equal to
the current CPU task, the request remains pending.
Note: Priority level 0000B is the default level of the CPU. Therefore, a request on
interrupt priority level 0000B will be arbitrated, but the CPU will never accept an
action request on this level. However, every enabled interrupt request (including
all denied interrupt requests as well as priority level 0000B requests) triggers a
CPU wake-up from idle state independent of the setting of the global interrupt
enable bit PSW.IEN.
Both the OCDS break requests and the hardware traps bypass the arbitration scheme
and go directly to the core.
5.1.3
Interrupt Control
All interrupt control registers are organized identically. The lower eight bits of an interrupt
control register contain the complete interrupt control and status information of the
associated source required during one round of prioritization (arbitration cycle). The
upper eight bits of the respective register are reserved. All interrupt control registers are
bit addressable and all bits can be read or written via software. Therefore, each interrupt
source can be programmed or modified with just one instruction. In the case of reading
the interrupt control registers with instructions that operate with word data types, the
upper 7 bits (15...9) will return zeroes. It is recommended to always write zeroes to these
bit positions. The layout of the interrupt control registers shown below is applicable to all
xxIC registers.
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xxIC
Interrupt Control Register
SFR
15
14
13
12
11
10
9
0
0
0
0
0
0
0
r
r
r
r
r
r
r
8
7
Reset Value: 0000H
6
5
4
3
2
1
0
GPX xxIR xxIE
ILVL
GLVL
rwh
rw
rw
rw
rw
Field
Bits
Type Description
GPX
[8]
rw
Group Priority Extension
Defines the value of high-order group level bit
xxIR1)
[7]
rwh
Interrupt Request Flag
0
No request pending
1
This source has raised an interrupt request
xxIE
[6]
rw
Interrupt Enable Control Bit
(individually enables/disables a specific source)
0
Interrupt request is disabled
1
Interrupt request is enabled
ILVL
[5:2]
rw
Interrupt Priority Level
FH Highest priority level
...
...
Lowest priority level
0H
GLVL
[1:0]
rw
Group Priority Level
3H
Highest priority level
...
...
0H
Lowest priority level
XGLVL
[8],[1:0]
1)
Extended Group Priority Level
7H
Highest priority level
...
...
0H
Lowest priority level
Bit xxIR supports bit-protection
The arbitration scheme allows nesting of up to fifteen interrupt service routines of
different priority levels (Level 0 cannot be used; see note above).
Note: To reduce power, the arbitration is stopped when no interrupt request is active.
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5.1.4
Interrupt Vector Table
The C166S V2 provides a vectored interrupt system. This system reserves the specific
vector locations in the memory space for the reset, trap, and interrupt service functions.
Whenever a request occurs, the CPU branches to the location associated with the
respective interrupt source. This vector position directly identifies the source causing the
request.
Note: Class B hardware traps all share the same interrupt vector. The status flags in the
Trap Flag Register (TFR) are used to determine which exception caused the trap.
For details, see Section 5.3.
The reserved vector locations are assembled into a vector table located in the address
space of the C166S V2. The vector table contains the appropriate jump instructions that
transfer control to the interrupt or trap service routines. These routines may be located
anywhere within the address space. The location and organization of the vector table is
programmable. The vector table can be located in all segments with exception of the
reserved segment 191. The Vector Segment register VECSEG specifies the segment of
the Vector Table.
VECSEG
Vector Segment Pointer
bSFR
7
Reset Value: xxxxH
15
14
13
12
11
10
9
8
0
0
0
0
0
0
0
0
VECSEG
r
r
r
r
r
r
r
r
rwh
Field
Bits
Type Description
VECSEG
[7:0]
rwh
6
5
4
3
2
1
0
Segment number of the Vector Table
The reset value of VECSEG can be configured during system reset or can be set
depending on the particular product. The C166S V2 supports the following reset values:
–
–
–
–
Start from Internal Program Memory (C0’0000H)
Start from Boot memory (BF’0000H)
Start from external memory (00’0000H)
Start from a segment specified from the system (xx’0000H)1)
The VECSC bit field of the CPUCON1 register controls the number of word locations
separating two vectors. The space between two vectors can be programmed to 2, 4, 8,
or 16 words.
1)
The current startup routine does not support this reset configuration.
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Each vector location has an offset address to the segment base address of the vector
table. The address can be easily calculated. The segment part is given by the VECSEG
register and the offset is the trap number shifted by the space programmed in the
VECSC bit field.
CPUCON1
CPU Control Register
SFR
Reset Value: 0000H
15
14
13
12
11
10
9
8
7
6
0
0
0
0
0
0
0
0
0
VECSC
r
r
r
r
r
r
r
r
r
rw
Field
Bits
Type Description
VECSC
[6:5]
rw
5
4
3
2
1
WDT SGT INT
BP
CTL DIS SCXT
rw
rw
rw
rw
0
ZCJ
rw
Scaling factor of Vector Table
00
Space between two vectors is 2 words
01
Space between two vectors is 4 words
10
Space between two vectors is 8 words
11
Space between two vectors is 16 words
Note: For a summary of the CPUCON1 register, please refer to Chapter 2.3.6.
5.1.5
Interrupt Jump Table Cache
The mechanism that uses the vector table location as the entry point for the interrupt
service routines can be overwritten by the Interrupt Controller (ITC). For a very fast
interrupt response time, the C166S V2 offers a new feature of the interrupt system—
Interrupt Jump Table Cache (also called “fast interrupt”). The ITC can transfer a 24-bit
vector to the CPU that is used directly as a start address for the service routine. This
feature skips the path through the vector table which normally saves the execution of at
least one branch. Due to the random nature of interrupt requests, execution of these
branches requires several CPU cycles, especially if memories with a high latency are
used, such as DRAMs. Therefore, avoiding the vector table may significantly improve
interrupt response time. However, the number of 24-bit vectors in the ITC is limited.
Fast interrupt is available for two interrupt sources with interrupt priority levels greater
than or equal to 12. The Interrupt Jump Table Cache skips the instruction fetches from
the interrupt vector table and executes a direct jump to the interrupt service routines
entry point. This feature is controlled by a set of two interrupt jump table cache registers
(FINTxCSP, FINTxADDR) for each of the two jump table entries.
Every interrupt jump table cache entry contains an enable bit, an associated arbitration
priority level (ILVL and GLVL), and the 24-bit address of the interrupt service routine.
Note that only the two lower bits of the interrupt priority level are selectable in the
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respective control registers. The two upper bits of the interrupt priority level are set to
‘11B’, which limits the allowed interrupt priority level to be greater than or equal to 12.
FINT0CSP
Fast Interrupt Control Register 0
11
10
XSFR
9
8
15
14
13
12
EN
0
0
GPX
ILVL
GLVL
SEG
rw
r
r
rw
rw
rw
rw
FINT1CSP
Fast Interrupt Control Register 1
11
10
7
Reset Value: 0000H
6
5
4
3
XSFR
9
8
7
2
1
0
Reset Value: 0000H
15
14
13
12
6
5
4
3
EN
0
0
GPX
ILVL
GLVL
SEG
rw
r
r
rw
rw
rw
rw
2
1
0
Field
Bits
Type Description
EN
[15]
rw
Fast Interrupt Enable
0
The interrupt jump table cache is disabled.
No fast interrupt is used.
1
The interrupt jump table cache is enabled.
A fast interrupt (direct jump to the interrupt
service routine) is used instead of the
normal fetch from the interrupt vector table.
GPX
[12]
rw
Group Priority Extension
This bit enables group extension for fast interrupts.
(hardwired to 0 for fewer than 64 interrupt nodes)
ILVL
[11:10] rw
Interrupt Priority Level
This bit field selects the lower two bits of the
interrupt priority level associated with this interrupt
jump table cache entry.
Note: The two upper bits of the interrupt priority
level are set to ‘11B’, which ends in an
interrupt priority level greater than or equal
to 12.
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Field
Bits
Type Description
GLVL
[9:8]
rw
Group Priority Level
This bit field selects the group priority level of the
associated interrupt jump table cache entry.
SEG
[7:0]
rw
Segment Number of Interrupt Service Routine
This bit field specifies address bits 23:16 of the
interrupt service routine´s entry point.
FINT0ADDR
Fast Interrupt Address Register 0
15
14
13
12
11
10
9
XSFR
8
14
13
12
11
10
9
6
5
4
3
2
1
0
ADDR
0
rw
r
FINT1ADDR
Fast Interrupt Address Register 1
15
7
Reset Value: 0000H
XSFR
8
7
Reset Value: 0000H
6
5
4
3
2
1
0
ADDR
0
rw
r
Field
Bits
Type Description
ADDR
[15:1]
rw
Address of Interrupt Service Routine
This bit field specifies address bits 15:1 of the
interrupt service routine’s entry point.
0
[0]
r
Interrupt Service Routine Address Bit 0
LSB of the interrupt service routine’s entry point
address is 0 because of word alignment.
5.2
Status and Switch Context Control
5.2.1
Interrupt Control Functions in the PSW
The Processor Status Word (PSW) is functionally divided into two parts: the lower byte
of the PSW represents the arithmetic status of the CPU, the upper byte of the PSW
controls the interrupt system of the C166S V2 CPU.
Note: For a summary of the PSW register, please refer to Section 2.6.6
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PSW
Processor Status Word
15
14
13
12
bSFR
11
10
9
8
ILVL
IEN
HLD
EN
BANK
rwh
rw
rw
rwh
Reset Value: 0000H
7
6
USR1 USR0
rwh
rwh
5
4
3
2
1
0
MUL
IP
E
Z
V
C
N
r
rwh
rwh
rwh
rwh
rwh
Field
Bits
Type Description
ILVL
[15:12] rwh
CPU Priority Level
Lowest Priority
0H
...
...
FH
Highest Priority
IEN
[11]
rw
Interrupt/PEC Enable Bit (globally)
0
Interrupt/PEC requests are disabled
1
Interrupt/PEC requests are enabled
BANK
[9:8]
rwh
Reserved for register file bank selection
00
Global register bank
01
Reserved
10
Local register bank 1
11
Local register bank 2
CPU Priority ILVL defines the current level for the CPU operation, thus, this bit field
reflects the priority level of the currently executed routine. When the CPU enters an
interrupt service routine this bit field is set to the priority level of the request that is being
serviced. The previous PSW is saved in the system stack before entering interrupt
service routine. To be serviced, any interrupt request must have a higher priority level
than the current CPU priority level. Any request of the same or a lower level will not be
acknowledged.
The current CPU priority level may be adjusted via software to select interrupt request
sources that can be serviced.
PEC transfers do not really interrupt the CPU, but rather “steal” some CPU cycle, so PEC
services do not influence the ILVL field in the PSW.
Hardware traps set the CPU level to the maximum priority (15). Therefore, no interrupt
or PEC requests will be acknowledged while an exception trap service routine is being
executed.
The TRAP instruction does not change the CPU level, so software trap service routines
may be interrupted by higher requests.
Register Bank BANK defines the currently used register bank for the CPU operation.
When the CPU enters an interrupt service routine, this bit field is updated to select the
register bank associated with the serviced request.
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Note: The TRAP instruction does not change the register bank.
Note: Hardware traps always use the global register bank.
Interrupt Enable bit IEN globally enables or disables interrupts and PEC operations.
When IEN is cleared, no new interrupt requests are accepted by the CPU after IEN was
set to 0. However, requests that have already entered the pipeline will be completed. If
IEN is set to 1, then all interrupt sources are globally enabled.
Note: To generate requests, interrupt sources must be also enabled by the interrupt
enable bits in their associated control register.
Note: Traps are non-maskable and, therefore, are not controlled by the IEN bit.
5.2.2
Saving the Status during Interrupt Service
Before an operating system or ITC can actually service a task switch request or interrupt,
the CPU must save the current task status. The C166S V2 CPU saves the CPU status
(PSW) along with the return address in the system stack. The return address defines the
point at which the execution of the interrupted task is to be resumed after returning from
the service routine. This return address is specified by the Instruction Pointer (IP) and,
in the case of a segmented memory model, also by the Code Segment Pointer (CSP).
Bit SGTDIS in the CPUCON1 register defines which memory model is used and,
therefore, controls how the return address is stored.
In the case of non-segmented mode, the system stack stores PSW first and then IP. In
segmented mode, PSW is followed by CSP and the IP. This order optimizes the use of
the system stack if segmentation is disabled.
The CPU priority field (ILVL in PSW) is updated with the priority of the interrupt request
that is to be serviced, so the CPU now executes on the new level.
The BANK field in the PSW register is changed to select the register bank associated
with the interrupt request. The associations between interrupt requests and register
banks are programmed in the Interrupt Controller (ITC).
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.
Status of
Interrupted Task
SP
---1. System Stack before
Interrupt Entry
Figure 5-3
SP
PSW
IP
-2. System Stack after
Interrupt Entry
(Unsegmented)
PSW
CSP
IP
SP
3. System Stack after
Interrupt Entry
(Segmented)
Task Status Saved on the System Stack
After accepting an interrupt request, the C166S V2 CPU sends an acknowledge to the
ITC that the requested interrupt is being serviced. The vector associated with the
requesting source is loaded into the IP and CSP and the first instruction of the service
routine is fetched. All other CPU resources, such as data page pointers and the context
pointer, are not affected.
When the CPU returns from the interrupt service routine (RETI is executed), the status
information is popped from the system stack in reverse order. The status information
contents depend on the SGTDIS bit value (see Figure 5-3).
5.2.3
Context Switching
An interrupt service routine usually saves all the registers it uses in the stack, and
restores them before returning. The more registers a routine uses, the more time is
wasted by saving and restoring. The C166S V2 CPU allows the complete bank of CPU
registers (GPRs) to be switched, so the service routine executes within its own separate
context. There are two ways to switch a context in the C166S V2 core (for details, see
Section 2.4.3):
1. Switching Context by Changing the Selected Register Banks
Selection of the register bank used in the interrupt task is programmed in the Interrupt
Controller. During the execution of the interrupt entry procedure, the change of the
register bank is automatically executed. After switching to one of the two local register
banks, the service routine may now use its “own registers” directly. This local register
bank is preserved when the service routine is terminated; thus, its contents are
available on the next call.
When switching to the global register bank, the service routine must also switch the
context of the global register bank (see the next section) to get a private set of GPRs.
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2. Switching Context of the Global Register Bank by Changing Context Pointer
The C166S V2 CPU allows the complete global register bank of CPU registers
(GPRs) to be changed with a single instruction; so, the service routine executes within
its own separate context. The instruction “SCXT CP, #New_Bank” pushes the
contents of the context pointer (CP) into the system stack and loads CP with the
immediate value “New_Bank”. The new CP value sets a new global register bank. The
service routine may now use its “own registers”. This global register bank is preserved
when the service routine is terminated; thus, its contents are available for the next call.
Before returning (RETI), the previous CP is simply popped from the system stack;
thus, returning the registers to the original global register bank.
Note: Resources used by the interrupting program must eventually be saved and
restored, such as the DPPs and the registers of the MUL/DIV unit.
There are certain timing restrictions during context switching that are associated
with pipeline behavior. For details, see Section 2.4.3.2.
5.2.4
Fast Bank Switching
The interrupt handler of the C166S V2 CPU supports an additional enhanced feature
(compared to other members of the C166 family) for normal interrupts called Fast Bank
Switching. To speed up interrupt handling, the core can use fast General Purpose
Register (GPR) bank switching for interrupts with an interrupt level greater or equal 12.
For every arbitration priority level with ILVL = ‘15D’-‘12D’ and XGLVL = ‘7D’-‘0D’, the
register bank can be selected via two bits. These bits are located in the two register bank
selection registers BNKSELx (x = 0,..,3). The BNKSEL2 and BNKSEL3 registers are
only implemented in configurations using the GPX extension bit.
BNKSELx (x = 0... 3)
Register Bank Selection Register x
15
14
13
12
11
10
9
XSFR
8
7
Reset Value: 0000H
6
5
4
3
2
1
0
GPRSEL7 GPRSEL6 GPRSEL5 GPRSEL4 GPRSEL3 GPRSEL2 GPRSEL1 GPRSEL0
rw
rw
rw
rw
Field
Bits
GPRSELx (x = 0... 7)
[x+1:x] rw
rw
rw
rw
rw
Type Description
Register Bank Selection
00
Global register bank
01
Reserved
10
Local register bank 1
11
Local register bank 2
Note: The GPRSELx value of the current triggered interrupt is automatically transferred
into the Program Status Word (PSW).
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Table 5-1 identifies the arbitration priority level assignment to the respective bit fields
within the four register bank selection registers:
Table 5-1
Register Bank Assignment
Interrupt
Priority
Level
(ILVL)
Group
Assigned
Priority GPRSELx
Register
Level
(XGLVL)
Interrupt
Priority
Level
(ILVL)
Assigned
Group
Priority GPRSELx
Level
Register
(XGLVL)
15
7
BNKSEL3.GPRSEL7 13
7
BNKSEL2.GPRSEL7
15
6
BNKSEL3.GPRSEL6 13
6
BNKSEL2.GPRSEL6
15
5
BNKSEL3.GPRSEL5 13
5
BNKSEL2.GPRSEL5
15
4
BNKSEL3.GPRSEL4 13
4
BNKSEL2.GPRSEL4
15
3
BNKSEL1.GPRSEL7 13
3
BNKSEL0.GPRSEL7
15
2
BNKSEL1.GPRSEL6 13
2
BNKSEL0.GPRSEL6
15
1
BNKSEL1.GPRSEL5 13
1
BNKSEL0.GPRSEL5
15
0
BNKSEL1.GPRSEL4 13
0
BNKSEL0.GPRSEL4
14
7
BNKSEL3.GPRSEL3 12
7
BNKSEL2.GPRSEL3
14
6
BNKSEL3.GPRSEL2 12
6
BNKSEL2.GPRSEL2
14
5
BNKSEL3.GPRSEL1 12
5
BNKSEL2.GPRSEL1
14
4
BNKSEL3.GPRSEL0 12
4
BNKSEL2.GPRSEL0
14
3
BNKSEL1.GPRSEL3 12
3
BNKSEL0.GPRSEL3
14
2
BNKSEL1.GPRSEL2 12
2
BNKSEL0.GPRSEL2
14
1
BNKSEL1.GPRSEL1 12
1
BNKSEL0.GPRSEL1
14
0
BNKSEL1.GPRSEL0 12
0
BNKSEL0.GPRSEL0
5.3
Traps
A software trap is initiated by the TRAP instruction. The TRAP instruction can call an
interrupt service routine by its associated vector number. The trap number specified in
the operand field of the trap instruction determines which vector location of the vector
table will be used.
5.3.1
Software Traps
The TRAP instruction is used to cause a software call to an interrupt service routine. The
trap number specified in the operand field of the trap instruction determines which vector
location of the vector table will be used.
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The TRAP instruction has an effect similar to an interrupt request at the same vector.
PSW, CSP (in segmentation mode), and IP are pushed into the system stack and then
a jump is taken to the specified vector location. When a software trap is executed, the
CSP for the trap service routine is loaded with the value of the VECSEG register. No
Interrupt Request flags are affected by the TRAP instruction. The interrupt service
routine called by a TRAP instruction must be terminated with a RETI (return from
interrupt) instruction to ensure correct operation.
Note: The CPU priority level and the selected register bank in PSW register are not
modified by the TRAP instruction; so, the service routine is executed with the
same priority level as the interrupt task. Therefore, the service routine entered by
the TRAP instruction can be interrupted by other traps or by higher priority
interrupts, unless triggered by a real hardware event. The service routine also
works with an unchanged register bank. If the hardware triggers the same service
routine, register bank can be selected by the ITC and may be different.
5.3.2
Hardware Traps
Hardware Traps are issued by faults or specific system states that occur during runtime
(not identified at compile time). The C166S V2 CPU distinguishes eight different
hardware trap functions. When a hardware trap condition has been detected, the CPU
branches to the trap vector location for the respective trap condition. The instruction
causing the trap event is completed before the trap handling routine is entered.
Hardware traps are not-maskable and always have a priority higher than any other CPU
task. If several hardware trap conditions are detected within the same instruction cycle,
the highest priority trap is serviced. In case of a hardware trap, the injection unit injects
an ITRAP instruction into the pipeline.
The ITRAP instruction performs the following actions:
– Pushes PSW, CSP (in segmented mode) and IP into the System Stack
– Sets CPU level in the PSW register to the highest possible priority level, which
disables all interrupts and DMA transfers
– Selects the global register bank for the trap service routine
– Branches to the trap vector location specified by the trap number of the trap condition
The eight hardware functions of the C166S V2 CPU are divided in two classes: Class A
and Class B.
Class A traps are:
–
–
–
–
External Non-Maskable Interrupts NMI
Stack Overflow
Stack Underflow
Software Break
These traps share the same trap priority, but have an individual vector address.
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Class B traps are:
–
–
–
–
Undefined Opcode
Parity Fault
Protection Fault
Illegal Word Operand Access
The Class B traps share the same interrupt node and interrupt vector. The bit
addressable Trap Flag Register (TFR) allows a trap service routine to identify the trap
that caused the exception.
The Trap Flag Register TFR
Each trap function is indicated by a separate request flag. When a hardware trap occurs,
the corresponding request flag in register TFR is set to 1.
TFR
Trap Flag Register
15
14
13
12
bSFR
Reset Value: 0000H
11
10
9
8
7
6
5
4
3
2
1
0
NMI
STK STK SOFT
OF UF BRK
0
0
0
0
UND
OPC
0
0
PAR PRT ILL
FLT FLT OPA
0
0
rwh
rwh
r
r
r
r
rwh
r
r
rwh
r
r
rwh
rwh
rwh
rwh
Field
Bits
Type Description
NMI1)
[15]
rwh
Non maskable interrupt flag
0
No non-maskable interrupt detected
1
Non-maskable interrupt detected
STKOF1)
[14]
rwh
Stack overflow flag
0
No stack overflow event detected
1
Stack overflow event detected
STKUF1)
[13]
rwh
Stack underflow flag
0
No stack underflow event detected
1
Stack underflow event detected
SOFTBRK1)
[12]
rwh
Software Break
0
No software break event detected
1
Software break event detected
UNDOPC1)
[7]
rwh
Undefined Opcode
0
No undefined opcode event detected
1
Undefined opcode event detected
PARFLT1)
[4]
rwh
Parity Fault2)
0
No parity fault event detected
1
Parity fault event detected
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Field
Bits
Type Description
PRTFLT1)
[3]
rwh
Protection Fault
0
No protection fault event detected
1
Protection fault event detected
ILLOPA1)
[2]
rwh
Illegal word operand access
0
No illegal word operand access event
detected
1
Illegal word operand access event detected
1)
This Bit supports bit-protection
2)
Parity fault on instruction fetch interface, usable for memories with parity check.
Note: The trap service routine must clear the respective trap flag; otherwise, a new trap
will be requested after exiting the service routine. Setting a trap request flag by
software causes the same effects as if it had been set by hardware.
The reset functions (hardware, software, watchdog) may be also regarded as a type of
trap. Reset functions have the highest priority (trap priority III). Class A traps have the
second highest priority (trap priority II). At the third rank are Class B traps (trap priority I);
thus, a Class A trap can interrupt a Class B trap.
Table 5-2
Hardware Trap Summary
Exception Condition
Trap
Flag
Reset Functions:
Hardware Reset
Software Reset
Watchdog Timer Overflow
Trap
Vector
Trap
Number
Trap
Priority
RESET
RESET
RESET
00H
00H
00H
III
III
III
Class A Hardware Traps:
Non-Maskable Interrupt
Stack Overflow
Stack Underflow
Software Break
NMI
STKOF
STKUF
SOFTBRK
NMITRAP
STOTRAP
STUTRAP
SBRKTRAP
02H
04H
06H
08H
II.3
II.2
II.1
II.0
Class B Hardware Traps:
Undefined Opcode
Parity Fault
Protection Fault
Illegal Word Operand Access
UNDOPC
PARFLT
PRTFLT
ILLOPA
BTRAP
BTRAP
BTRAP
BTRAP
0AH
0AH
0AH
0AH
I
I
I
I
Class A Trap
Class A traps are generated by the high priority system NMI or by special CPU events
such as the software break, a stack overflow, or an underflow event. Class A traps are
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not used to indicate hardware failures. After a Class A event, a dedicated service routine
is called to react to the events. Each Class A trap has its own vector location in the vector
table. After finishing the service routine, the instruction flow must be further correctly
executed. This explains why Class A traps cannot interrupt atomic/extend sequences
and I/O accesses in progress. For example, an interrupted extend sequence cannot be
restarted.
All Class A traps are generated in the pipeline during the execution of instructions, with
an exception of NMI, which is an asynchronous external event. It is not possible for two
different instructions in the pipeline to generate traps in the same CPU cycle. Class A
trap events can be generated only during the memory stage of execution. The execution
of instructions which caused a Class A trap event is always completed. In the case of a
Class A trap, the pipeline is directly canceled and the IP of the instruction following the
last executed one is pushed into the stack. In the case of an atomic/extend sequence or
I/O read access in progress, the execution continues till the sequence completion. Upon
completion of the sequence, the IP of the instruction following the last one executed is
pushed into the stack. Therefore, in the case of a Class A trap, the stack always contains
the IP of the first not-executed instruction in the instruction flow.
Note: The Branch Folding Unit allows an execution of branch instructions in parallel with
the preceding instruction. The pre-processed branch instruction is combined with
the preceding instruction. The branch is executed together with the instruction
which caused the Class A trap. The IP of the first following not-executed
instruction in the instruction flow is then pushed on the stack.
If more than one Class A trap occurs at a same time, they are prioritized internally. The
NMI trap has the highest priority and the software break has the lowest.
Note: In the case of two different Class A traps occurring simultaneously, both trap flags
are set. The IP of the instruction following the last one executed is pushed into the
stack. The trap with the higher priority is executed. After return from the service
routine, the IP is popped from the stack and immediately pushed again because
of the other pending Class A trap (unless the trap related to the second trap flag
in TFR has been cleared by the first trap service routine).
Class B Trap
Class B traps are generated by unrecoverable hardware failures. In the case of a
hardware failure, the CPU must immediately start a failure service routine. Class B traps
can interrupt an atomic/extend sequence and an I/O read access. After finishing the
Class B service routine, a restoration of the interrupted instruction flow is not possible.
All Class B traps have the same priority (trap priority I). When several Class B traps
become active at the same time, the corresponding flags in the TFR register are set and
the trap service routine is entered. Because all Class B traps have the same vector, the
priority of service of simultaneously occurring Class B traps is determined by the
software in the trap service routine.
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The Parity Fault is an asynchronous external event while all other Class B traps are
generated in the pipeline during the execution of instructions. It is not possible for two
different instructions in the pipeline to generate Class A and Class B traps in the same
CPU cycle. Class B trap events can be generated only during memory stage execution.
Instructions which caused a Class B trap event are always executed. In the case of a
class B trap, the pipeline is directly canceled and the IP of the instruction following the
one which caused the trap is pushed on the stack. Therefore, the stack always contains
the IP of the first following not-executed instruction in the instruction flow.
Note: The Branch Folding Unit allows the execution of branch instructions in parallel with
the preceding instruction. The pre-processed branch instruction is combined with
the preceding instruction. The branch is executed together with the instruction
causing the Class B trap. The IP of the first following not-executed instruction in
the instruction flow is pushed into the stack.
During execution of a Class A trap service routine, any Class B trap will not be serviced
until the Class A trap service routine is exited with a RETI instruction. In this case, the
Class B trap condition is stored in the TFR register, but the IP value of the instruction
which caused this trap will be lost.
Note: If a Class A trap occurs simultaneously with a Class B trap, both trap flags are set.
The IP of the instruction following the one which caused the trap is pushed into the
stack, and the Class A trap is executed. If this occurs during execution of an
atomic/extend sequence or I/O read access in progress, then the presence of the
Class B trap breaks the protection of atomic/extend operations and the class A
trap will be executed immediately without waiting for the sequence completion.
After return from the service routine, the IP is popped from the system stack and
immediately pushed again because of the other pending Class B trap. In this
situation, the restoration of the interrupted instruction flow is not possible.
• External NMI Trap: Whenever a high to low transition on the dedicated external NMI
pin (Non-Maskable Interrupt) is detected, the NMI flag in register TFR is set and the
CPU will enter the NMI trap routine.
• Stack Overflow Trap: Whenever the stack pointer is implicitly decremented and the
stack pointer is equal to the value in the stack overflow register STKOV, the STKOF
flag in register TFR is set and the CPU will enter the stack overflow trap routine.
• Stack Underflow Trap: Whenever the stack pointer is implicitly incremented and the
stack pointer is equal to the value in the stack underflow register STKUN, the STKUF
flag is set in register TFR, and the CPU will enter the stack underflow trap routine.
• Software Break Trap: When the instruction currently being executed by the CPU is
a SBRK instruction, the SOFTBRK flag is set in register TFR and the CPU enters the
software break debug routine. The flag generation of the software break instruction
can be disabled by an On-chip Emulation Module. In this case, the instruction only
breaks the instruction flow and signals this event to the debugger. The flag is not set
and the trap will not be executed.
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• Undefined Opcode Trap: When the instruction currently being decoded by the CPU
does not contain a valid C166S V2 CPU opcode, the UNDOPC flag is set in register
TFR and the CPU enters the undefined opcode trap routine. The instruction that
causes the undefined opcode trap is executed as a NOP.
• Parity Fault Trap: When a parity error is detected in the system, the PARFLT flag is
set in register TFR and the CPU enters the parity fault trap routine. For the C166S V2
CPU, the parity fault is an asynchronous system event. There is no link between the
fault and the instruction flow itself.
• Protection Fault Trap: Whenever one of the special protected instructions is
executed where the opcode of that instruction is not repeated twice in the second word
of the instruction and the byte following the opcode is not the complement of the
opcode, the PRTFLT flag in register TFR is set and the CPU enters the protection fault
trap routine. The protected instructions include DISWDT, EINIT, IDLE, PWRDN,
SRST, ENWDT and SRVWDT. The instruction that causes the protection fault trap is
executed like a NOP.
• Illegal Word Operand Access Trap: Whenever a word operand read or write access
is attempted to an odd byte address, the ILLOPA flag in register TFR is set and the
CPU enters the illegal word operand access trap routine.
5.4
Peripheral Event Controller
The Peripheral Event Controller (PEC) makes a decision about the CPU action required
to manage an interrupt request. It may be either normal interrupt service or fast data
transfer between two memory locations. The C166S V2 PEC controls eight fast data
transfer channels.
If normal interrupt is requested, the CPU temporarily suspends the current program
execution and branches to an interrupt service routine. The current program status and
context must be preserved.
If a PEC channel is selected for servicing an interrupt request, a single word or byte data
transfer between any two memory locations is to be performed. During a PEC transfer,
the normal program execution of the CPU is halted. No internal program status
information needs to be saved. The PEC transfer is the fastest possible interrupt
response. In many cases, a PEC transfer is sufficient to service the peripheral request
(serial channels, for example).
The PEC channels can perform the following actions:
• Byte or word transfer
• Continuous data transfer
• PEC channel-specific interrupt request upon data transfer completion or common for
all channels “End of PEC” interrupt for enhanced handling
• Automatic increment of source or/and destination pointers with support of memory to
memory transfer
Note: PEC transfer is executed if its priority level is higher than current CPU priority level.
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5.4.1
PEC Control Registers
Each PEC channel is controlled by the respective PEC channel Control register (PECCx)
and a set of source and destination pointers (SRCPx, DSTPx and PECSEGx), where ‘x’
stands for the PEC channel number. The PECCx registers control the arbitration priority
level assignment to the PEC channels and the action to be performed.
PECCx
PEC Channel Control Register (x=7-0)
13
12
11
10
9
SFR
8
7
Reset Value: 0000H
15
14
6
5
4
3
0
EOP
INT
PLEV
CL
INC
BWT
COUNT
r
rw
rw
rw
rw
rw
rwh
2
1
0
Field
Bits
Type Description
EOPINT
[14]
rw
End of PEC Interrupt Selection
0
End of PEC interrupt with the same level as
the PEC transfer is trigger
1
End of PEC interrupt is serviced by a
separate interrupt node with programmable
interrupt level (EOPIC) and interrupt sharing
control register (PECISNC)
PLEV
[13:12] rw
PEC Level Selection
This bit field controls the PEC channel assignment
to an arbitration priority level.
(see section below)
CL
[11]
Channel Link Control
0
PEC channels work independently
1
Pairs of PEC channels are linked together
[10:9]
User Manual
rw
Increment Control
(Modification of source and destination pointer
after PEC transfer)
00
No modification
01
Increment of destination pointer DSTPx
by 1 (BWT = 1) or by 2 (BWT = 0)
10
Increment of source pointer SRCPx
by 1 (BWT = 1) or by 2 (BWT = 0)
11
Increment of destination pointer DSTPx and
source pointer SRCPx
by 1 (BWT = 1) or by 2 (BWT = 0)
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Field
Bits
Type Description
BWT
[8]
rw
Byte/Word Transfer Selection
0
Transfer a word
1
Transfer a byte
COUNT
[7:0]
rwh
PEC Transfer Count
Counts PEC transfers and influences the
channel´s action (see section below)
The Byte/Word Transfer bit (BWT) of the PECCx register determines if a byte or a word
is to be moved during a PEC service cycle and defines an increment step size for the
pointer(s) to be modified.
The PEC Transfer Count field (COUNT) of the PECCx directly controls the action of the
respective PEC channel. The contents of the bit field COUNT may specify a certain
number of PEC transfers, unlimited transfers, or no PEC service at all.
– If the PEC transfer counter COUNT value is set to 00H, the normal interrupt requests
are processed instead of PEC data transfers and the corresponding PEC channel
remains idle.
– Continuous data transfers are selected by setting the bit field COUNT to FFH value.
In this case, COUNT is not decremented by the transfers and the respective PEC
channel can serve unlimited number of PEC requests until it is modified by the
program.
– If the bit field COUNT is set to service a specified number of requests by the respective
PEC channel, it is decremented with each PEC transfer and the request flag is cleared
to indicate that the request has been serviced. When COUNT reaches 00H, it
immediately activates the interrupt service routine that has the same priority level
(EOPINT = 0) or triggers the “End of PEC” interrupt with a different priority level
(EOPINT = 1). When COUNT is decremented from 01H to 00H after a data transfer,
the request flag will be cleared if EOPINT is set to 1. If EOPINT is 0, the request flag
will not be cleared and another interrupt request will be generated on the same priority
level. The respective PEC channel remains idle and the associated interrupt service
routine is activated instead of PEC transfer because COUNT contains the 00H value.
(see Section 5.4.3).
The EOPIC register is the interrupt control register of the End Of PEC interrupt.
The Register PECISNC contains flags of the “End of PEC” interrupt node. This node is
used when enhanced “End of PEC” interrupt feature was invoked and control bit EOPINT
is set to 1 in the corresponding PECCx.
Figure 5-4 shows the usage of the “End of PEC” interrupt subnode:
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EOPIC
Interrupt Control Register1)
1)
bESFR
15
14
13
12
11
10
9
0
0
0
0
0
0
0
r
r
r
r
r
r
r
8
7
Reset Value: 0000H
6
5
4
3
2
1
0
EOP
GPX EOP
IR
IE
ILVL
GLVL
rwh
rw
rw
rw
rw
The EOPIC register is assigned to one of the interrupt nodes. The assignment is product specific.
Field
Bits
Type Description
GPX
[8]
rw
Group Priority Extension
Defines the value of high-order group level bit
EOPIR1)
[7]
rwh
Interrupt Request Flag
0
No request pending
1
The source has raised an interrupt request
EOPIE
[6]
rw
Interrupt Enable Control Bit
0
Interrupt request is disabled
1
Interrupt request is enabled
ILVL
[5:2]
rw
Interrupt Priority Level
FH
Highest priority level
...
...
Lowest priority level
0H
GLVL
[1:0]
rw
Group Priority Level
3H
Highest priority level
...
...
0H
Lowest priority level
XGLVL
[8],[1:0]
1)
Extended Group Priority Level
7H
Highest priority level
...
...
0H
Lowest priority level
Bit EOPIR supports bit-protection
PECISNC
PEC Interrupt Sub Node Control
15
14
13
12
11
10
bSFR
9
8
7
Reset Value: 0000H
6
5
4
3
2
1
0
C7IR C7IE C6IR C6IE C5IR C5IE C4IR C4IE C3IR C3IE C2IR C2IE C1IR C1IE C0IR C0IE
rwh
rw
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rw
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rw
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rw
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Field
Bits
CxIR
15, 13, rwh
11, 9,
7, 5, 3,
1
Interrupt Sub Node Request Flag of PEC
Channel x 1) 2)
0
No special end of PEC interrupt request is
pending for PEC channel x
1
PEC channel x has raised an end of PEC
interrupt request
CxIE
14, 12, rw
10, 8,
6, 4, 2,
0
Interrupt Sub Node Enable Control Bit
of PEC Channel x 1) 3)
(individually enables/disables a specific source)
0
End of PEC interrupt request of PEC
channel x is disabled
1
End of PEC interrupt request of PEC
channel x is enabled
1)
2)
3)
Type Description
x = 7...0
NOTE:
The “End of PEC” sub-node interrupt request flags are not cleared by hardware when entering the interrupt
service routine (interrupt has been accepted by the CPU), unlike the interrupt request flags of the interrupt
nodes (request flags xxIC.xxIR). The interrupt service routine must check the request flags and clear them
before executing the RETI instruction.
It is recommended to clear an interrupt request flag (CxIR) before setting the respective enable flag (CxIE).
Otherwise, former requests still pending will immediately trigger an interrupt request after setting the enable bit.
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PECISNC
C7IR C7IE C6IR C6IE C5IR C5IE C4IR C4IE C3IR C3IE C2IR C2IE C1IR C1IE C0IR C0IE
15
0
Interrupt Request
Pulse Generator
EOPIC
0
15
Figure 5-4
0
0
0
0
0
0
GPX
EOP EOP
IE
IR
87
ILVL
GLVL
0
End of PEC Interrupt Sub Node
Table 5-3 summarizes the values the bit field COUNT and the corresponding PEC
channel actions.
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Table 5-3
PEC Channel Actions
Previous
COUNT Field
Value
Modified
COUNT Field
Value
Action of PEC Channel
and Comments
FFH
FFH
Move a Byte/Word
Continuous transfer mode; COUNT is not modified
FEH...02H
FDH...01H
Move a Byte/Word and decrement COUNT
01H
00H
Move a Byte/Word
Depending on bit EOPINT, one of two different
actions are taken:
EOPINT = 0 (compatible mode)
The service request flag (xxIR) of the respective
interrupt remains set (it is cleared for all other
COUNT values). Therefore, an additional interrupt
request is triggered on the next arbitration cycle with
a COUNT field value of ‘00H’ (see next raw)
EOPINT = 1
The service request flag (xxIR) of the respective
interrupt is cleared. Additionally, the interrupt
request flag of the EOP sub node (PECISNC.CxIR)
is set. Furthermore, the interrupt request flag of the
end of PEC interrupt node (EOPIC.EOPIR) is
automatically set if the sub node request is enabled
(PECISNC.CxIE = 1).
(see also Section 5.4.3)
00H
00H
No PEC action
A normal interrupt is requested instead of a PEC
data transfer (see also Section 5.4.3).
The Increment Control Field (INC) of the PECCx register defines when ether one or
both of the PEC pointers must be incremented after the PEC transfer. If the pointers are
not to be modified (INC=‘00’), the respective channel will always move data from the
same source to the same destination.
Channel Link Mode (CL bit)
Channel linking allows to perform PEC data transfers via a pair of two PEC channels,
that are switched rotationaly, to provide the possibility of data chaining. The linked
transfer is in principal the same as described for standard PEC but if the transfer of a
linked channel has finished by decrementing the transfer count to zero the PEC
controller automatically switches to the partner channel of the pair. While the data
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transfers are then controlled by the partner channel the finished channel can be
reconfigured. The termination of the transfers of a linked channel is indicated by the
triggering of an interrupt. If the channel link bit CL of the active channel or the EOPINT
flag is set a End of PEC interrupt is called. Otherwise, the standard interrupt connected
to the even channel is requested.
The switch to the PEC channel partner is only possible if channel linking is enabled by
setting the PECCx.CL bit of the current channel x. If for a channel the link bit is set but
its count value is zero no switch is performed but the normal interrupt of the PEC channel
calling node is requested when a new interrupt request occurs for the corresponding
node. So the complete linked transfer is terminated if either in the active channel the
count value is 0 or the CL flag is 0. Possible channel pairs are only the combinations of
channels 0/1, 2/3, 4/5 and 6/7. The PEC channel assignment of the odd numbered
channels is ignored if at least one of the channel linking bits (CL) of the channel pair is
set. This means an interrupt request connected to the odd channel triggers only the
standard interrupt, but no PEC transfer. So, the channel pair is assigned to the interrupt
and group level of the even numbered channel partner. After the first initialization for
linked transfer the transfer is started with the even numbered channel. The channels
toggle as long as CL bit of the currently active channel is set on the transition of the PEC
transfer count value from 1 to 0. The even channel is automatically selected if both CL
flags are 0 or both transfer counts are 0. In all other cases the last active channel stays
selected. A reset of the CL bits during a programmed channel link mode may cause a
corruption of the sequence.
A chained PEC sequence should be programmed so that as long the sequence is not
finished, the CL bit is set, together with a new transfer count value. For the transfer
before the last transfer, the called END of PEC interrupt routine should not reconfigure
the count value and should not reset the CL bit. The last transfer channel should not have
the CL bit set. So, at the end of the complete transfer, either a standard or an END of
PEC trap can be selected by the EOPINT bit of the last channel.
5.4.2
The PEC Source and Destination Pointer
The PEC channels source and destination pointers specify the locations between which
the data is to be moved. All pointers are 24-bits wide. The 24-bit source address is stored
in the register SRCPx (lower 16 bits of address) and in the high byte of register
PECSEGx (highest 8 address bits).
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PECSEGx
SRCSEGx
15
DSTSEGx
0
8 7
SRCPx
DSTPx
SRCPx
15
DSTPx
0
15
Source Pointer
23
16 15
Segment Address
0
Destination Pointer
0
23
Segment Offset
16 15
Segment Address
0
Segment Offset
Data Transfer
x = 7...0, depending on PEC channel number
Figure 5-5
PEC Pointer Address Handling
The 24-bit destination address is stored in the register DSTPx (lower 16 bits of address)
and in the low byte of register PECSEGx (highest 8 address bits). Only the lower 16 bits
of the PEC address pointers (segment offset) can be modified (incremented) by the PEC
transfer mechanism. The highest 8 bits, which represent the segment number, are not
modified by hardware. Therefore, the PEC pointers may be incremented within the
address space of one segment and may not cross the segment border. If the offset
address pointer gets the ‘FFFFH’ value in the case of byte transfers (BWT = 1) or ‘FFFEH’
in the case of word transfers (BWT = 0), the next increment will be disregarded. The
address register will keep one of these maximum values and no overflow will happen.
The described behavior protects the memory from unintentional overwriting. No explicit
error event is generated by the system in case of address pointer(s) saturation;
therefore, it is the user’s responsibility to prevent this condition.
Note: PEC data transfers do not use the data page pointers DPP3...DPP0.
Note: If a word data transfer is selected for a specific PEC channel (BWT = 0), the
respective source and destination pointers must both contain a valid word address
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that points to an even byte boundary. Otherwise, the Illegal Word Access trap will
be invoked when this channel is used.
SRCPx
PEC Source Pointer (x=7-0)
15
14
13
12
11
XSFR
10
9
8
7
Reset Value: 0000H
6
5
4
3
2
1
0
SRCPx
rwh
Field
Bits
Type Description
SRCPx
[15:0]
rwh
Source Pointer Address of Channel x
Source Address bits 15-0
DSTPx
PEC Destination Pointer (x=7-0)
15
14
13
12
11
10
xSFR
9
8
7
Reset Value: 0000H
6
5
4
3
2
1
0
DSTPx
rwh
Field
Bits
Type Description
DSTPx
[15:0]
rwh
Destination Pointer Address of Channel x
Destination Address bits 15-0
PECSEGx
PEC Segment Pointer (x=7-0)
15
14
5.4.3
13
12
11
10
xSFR
9
8
7
Reset Value: 0000H
6
5
4
3
SRCSEGx
DSTSEGx
rw
rw
2
1
0
PEC Handler Interrupt Actions Summary
As described above, two different kinds of interrupts can be triggered by the PEC handler
depending on the status of the bitfield COUNT.
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Field
Bits
Type Description
SRCSEGx
[15:8]
rw
Source Pointer Segment Address of Channel x
Source Address bits 23-16
DSTSEGx
[7:0]
rw
Destination Pointer Segment Address of
Channel x
Destination Address bits 23-16
• PEC channel is enabled1) and the bit field COUNT has a value higher than ‘01H’.
a) Control bit EOPINT = 0 or 1
ACTIONS:
– PEC request is proceeded
– No other interrupt activity
• PEC channel is enabled and the bit field COUNT gets a decrement from ‘01H’ to ‘00H’
triggered by a service request.
a) Control bit EOPINT = 0 (compatible with C166)
ACTIONS:
– PEC request is proceeded
– Interrupt request flag (xxIR) of the requesting interrupt node (arbitration winner) is
not cleared, participates on the next arbitration cycle, and triggers a normal interrupt
on the same level as the PEC request is served.
b) Control bit EOPINT = 1 (enhanced end of PEC interrupt feature)
ACTIONS:
– PEC request is proceeded
– Interrupt request flag (xxIR) of requesting interrupt node (arbitration winner) is
cleared and will not trigger more actions.
– Interrupt request flag of the end of PEC interrupt subnode will be set
(PECISNC.CxIR = 1)
– If the respective interrupt enable flag of the end of PEC interrupt subnode was set
before by software (PECISNC.CxIE = 1), an end of PEC interrupt is requested
(EOPIC.EOPIR = 1). This end of PEC interrupt participates on the next arbitration
cycle with its priority (selected via EOPIC.ILVL and EOPIC.GLVL), if this interrupt
source was enabled before by software (EOPIC.EOPIR = 1). With this behavior, an
end of PEC interrupt can be triggered on a level lower than the respective PEC
requests have been serviced.
• PEC channel is disabled if the bit field COUNT is cleared (either by hardware or by
software).
1)
Every PEC channel is automatically enabled when its COUNT value is greater than 00H.
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a) Control bit EOPINT = 0 or 1
ACTIONS:
– A normal interrupt service routine is requested on the PEC channel priority level.
5.4.4
PEC Channel Assignment and Arbitration
The C166S V2 PEC channels can be assigned to a certain arbitration priority level. All
requests with interrupt priority levels 8 to 15 and group levels 0 to 3 can be associated
with the PEC functionality (eight PEC channels in total). The group extension is not
supported for PEC requests, because the 8 PEC channels are assigned to two interrupt
levels for compatibility to the C16x family.
The following mechanism shows how to program the bit field PECCx.PLEV to set up a
link to a certain interrupt priority level and a group priority level:
PEC Channel x
is linked to:
Interrupt priority level (in IC register): (1, ~PLEV.1, ~PLEV.0, x.0)
Extended Group priority level:
(0,
x.1,
x.0)
For an easier understanding of this formula, Table 5-4 lists all possible combinations.
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Table 5-4
PEC Channel Assignment
Arbitration Priority
Level
Interrupt
Priority
Level
xxIC.ILVL
PEC
Channel x
Group
PLEV Ch
Priority
Level
xxIC.XGLVL
00
Arbitration Priority
Level
PEC
Channel x
Interrupt
Priority
Level
xxIC.ILVL
Group
PLEV Ch
Priority
Level
xxIC.XGLVL
7
11
3
15
3
15
2
6
11
2
6
15
1
5
11
1
5
15
0
4
11
0
4
14
3
3
10
3
3
14
2
2
10
2
2
14
1
1
10
1
1
14
0
0
10
0
0
13
3
7
9
3
13
2
6
9
2
6
13
1
5
9
1
5
13
0
4
9
0
4
12
3
3
8
3
3
12
2
2
8
2
2
12
1
1
8
1
1
12
0
0
8
0
0
01
10
11
7
7
All interrupt requests not assigned to a PEC channel go directly to the interrupt handler.
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5.5
CPU Action Control Unit
The CPU Action Control Unit multiplexes interrupt/PEC requests with OCDS requests
and forwards them to the CPU demanding the corresponding action. It also routes
request acknowledges and denies from the core to the corresponding requester. The
OCDS requests have programmable priority levels. If another interrupt request that has
won an arbitration conflicts with an OCDS request, the one with the higher priority will
trigger the CPU action first. However, if both requests (Interrupt/PEC and OCDS) have
the same priority level, the interrupt/PEC request wins.
The OCDS break request is sent directly from the OCDS module to the CPU (where it is
prioritized) and ignores the CPU Action Control Unit (or any other module of the interrupt
and Peripheral Event Controller).
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6
External Bus Controller
6.1
Introduction
Although the C166S V2 products provide a powerful set of on-chip peripherals and onchip program and data memories, these internal units only cover a small fraction of the
C166S V2´s address space of up to 16 MByte. The external bus interface allows access
to external1) peripherals and additional volatile and non-volatile memories. The external
bus interface provides a number of configurations, so it can be tailored to fit perfectly into
a given application system.
Accesses to external memories or peripherals are executed by the integrated External
Bus Controller (EBC). The function of the EBC is controlled via a set of configuration
registers. The basic behavior can be programmed via the mode selection registers
EBCMODx.
The EBC supports up to eight external chip select channels. Each of these chip select
signals is programmable via a set of registers. The FCONCSx registers specify the
external bus cycles in terms of address (mux/demux), data (16-bit/8-bit), chip select
enable and READY control. The timing of the bus access is controlled by the timing
configuration registers TCONCSx, which specify the length of the different access
phases. All these parameters are used for accesses within a specific address area which
is defined via the corresponding address select register ADDRSELx.
The seven register sets FCONCS1/TCONCS1/ADDRSEL1 to FCONCS7/TCONCS7/
ADDRSEL7 define seven independent ‘address windows’, while all external accesses
outside these windows are controlled via the registers FCONCS0 and TCONCS0. Two
additional chip select channels with fixed address ranges are defined for the startup and
the monitor memory.
The external bus timing is related to the reference clock output CLKOUT. All bus signals
are generated in relation to the rising edge of this clock. This behavior eases the timing
specification drastically and allows high EBC operating frequencies above 100 MHz. The
external bus protocol is compatible with the C16x ones. However, the external bus timing
is improved in terms of wait state granularity.
Note: For supporting these improvements, an extended configuration scheme
compared to the C16x is defined. The C16x registers SYSCON and BUSCONx
are no longer used. In principle the configuration of the external bus controller is
done during the application initialization. Therefore, only some initialization code
has to be adapted for using the C166S V2 EBC module instead of the C16x
external bus controller.
1)
C166S V2:’External’ means off-chip However, modules like customer ASIC, startup memory and additional
peripherals and memories can be connected on-chip to the external bus module as well. These modules are
from the controller sub-system point of view also external, but on-chip.
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6.2
Timing Principles
The EBC supports four different access types. Reads and Writes in multiplexed and
demultiplexed mode. Multiplexed mode means that the data bus is used in a ‘timemultiplex’ for address (the 16 LSBs) and for data. In demultiplexed mode the data bus is
used for data only and an additional 16 bit address bus is available.
Naming Conventions
• ALE
Address Latch Enable (high active)
indicates that the applied address is valid
• WR/
Write Strobe (low active)/
WRL
Write Low Byte Strobe (low active)
configured either to a general write request or a write request for the low
byte (see Table 6-1)
• BHE/
Byte High Enable (low active)/
Write High Byte Strobe (low active)
WRH
configured either to an enable for the high byte or a write request for the
high byte (see Table 6-1)
Read Strobe (low active)
• RD
• READY Ready to indicated end of actions (programmable polarity)
• ADDR
Address Bus split to a part [23:16] and [15:0]
• DATA
Data Bus [15:0] or shared Data/Address [15:0] Bus
• HOLD
Hold input for foreign bus requests (low active)
Hold Acknowledge (low active)
• HLDA
master output to grant bus / slave input
• BREQ
Bus Request (low active)
Table 6-1
Write Configurations (see Chapter 6.3.2)
written byte
general write configuration
separated byte low/high writes
low
high
WR
BHE
ADDR[0]
WRL
WRH
ADDR[0]
-
-
inactive
don’t care
0/1
inactive
inactive
0/1
write
-
active
inactive
0
active
inactive
0/1
-
write
active
active
1
inactive
active
0/1
write
write
active
active
0
active
active
0/1
The timings of the external bus can be split up into six phases:
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Figure 6-1
Demultiplexed Bus Read
a
b
c
e
d
f
ALE
valid
ADDR, CS
RD
valid
read DATA
Figure 6-2
clock cycles
0-3 1-2
needed bits
2 1
0-3
0-1
2
1
1-32
0-3
5
2rd
2wr
Demultiplexed Bus Write
a
b
c
d
e
f
ALE
valid
ADDR, CS
WR
valid
write DATA
•
•
•
•
•
•
a phase:
b phase:
c phase:
d phase:
e phase:
f phase:
User Manual
clock cycles
0-3 1-2
needed bits
2
1
0-3
2
0-1
1
1-32
0-3
5
2rd
2wr
addresses valid, ALE high, no command. CS switch tristate wait states
addresses valid, ALE high, no command. ALE length
addresses valid, ALE low, no command. R/W delay
write data valid, ALE low, no command. Data valid for write cycles
command (read or write) active. Access time
command inactive, address hold. Read data tristate time, write data hold
time
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Figure 6-3
Multiplexed Bus Read
a
b
c
d
e
f
ALE
valid
ADDR, CS
RD
addr valid
read DATA
clocks
0-3 1-2
needed bits
Figure 6-4
2
1
data in valid
0-3
0-1
1-32
0-3
2
1
5
2rd
Multiplexed Bus Write
a
b
c
d
e
f
ALE
valid
ADDR, CS
WR
write DATA
clocks
needed bits
•
•
•
•
address valid
0-3 1-2 0-3
2 1
2
data out valid
next address
0-1
1-32
0-3
1
5
2wr
a phase:
b phase:
c phase:
d phase:
addresses valid, ALE high, no command. CS switch tristate wait states
addresses valid, ALE high, no command. ALE length
addresses valid, ALE low, no command. Address hold, R/W delay
address tristate for read cycles, data valid for write cycles, ALE low, no
command
• e phase: command (read or write) active. Access time
• f phase: command inactive, address hold. Read data tristate time, write data hold
time.
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6.2.1
A Phase
The A phase can take 0-3 clocks. It is used to tristate the databus drivers activated in
the previous cycle (tristate wait states after CS switch).
Phase A cycles are not inserted in every access cycle but only when changing the CS.
If an access using one chipselect CSx was finished and the next access with a different
chipselect CSy is started then Phase A cycles are performed according to the PHA bits
set for the first chipselect CSx. This feature is used to optimize wait states with devices
having a long turn off delay at their databus drivers like EPROM and FLASH.
The A Phase cycles are inserted while the addresses and ALE of the next cycle are
already applied.
If there are idle cycles in between two accesses these clock cycles are taken into
account and the A Phase is shortened accordingly. For example if there are three tristate
cycles programmed and two idle cycles occurred then the A Phase takes only one clock
cycle.
6.2.2
B Phase
The B phase can take 1-2 clocks. It is used for selecting devices and registers before
giving a command and to define the length of the active ALE. In multiplexed bus mode
the address is applied on the data bus for latching.
6.2.3
C Phase
The C phase is similar to the A and B phases but ALE is already low. It can take 0-3
clock cycles.
In multiplexed bus mode the address is held for being latched safely. Phase C cycles can
be used to delay the command signals (RW delay).
6.2.4
D Phase
The D phase can take 0-1 clocks. It is used to tristate the address on the multiplexed
bus when a read cycle is performed. For all write cycles it is used to have the data valid
on the bus before the command is applied.
6.2.5
E Phase
The E phase is the command respectively access phase and takes 1-32 clocks. Read
data is fetched, write data is put onto the bus; the command signals are active. Read
data is registered with the terminating clock cycle of this phase.
The READY function is lengthening this phase, too (see Table 6.3.6). READY controlled
access cycles have a random cycle time.
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6.2.6
F Phase
The F phase can take 0-3 clocks. Addresses and write data are held while the command
is inactive. The number of wait states being inserted at the F phase is programmable
independently for read and write accesses. The F phase is used for data reads to
program tristate wait states on the bidirectional data bus in order to avoid bus conflicts.
6.3
Functional Description
6.3.1
Configuration Register Overview
The EBC registers are functionally split up into three groups:
• EBC mode registers that have influence on global functions.
• Chip select related registers to configure the functionality, timing and size of the
chipselect windows.
• Startup and Monitor Memory registers to control the access to these dedicated
memories.
CS0 is the default chip select that selects all address space not addressed by another
chip select or occupied by internal address space. Therefore CS0 has no ADDRSEL
register.
All EBC registers are write protected by the EINIT protection mechanism. This means
that after execution of the EINIT instruction by the C166S V2 CPU these registers are
not writeable anymore.
For a list of all EBC control registers refer to Chapter 9.4. All EBC registers are located
in a 128 byte segment.
6.3.2
The EBC MODE Registers EBCMODx
EBC Mode Register 0
EBCMOD0
15
14
RDY RDY
POL DIS
rw
rw
13
12
ALE
DIS
BYT
DIS
rw
rw
XSFR
11
10
WR EBC
CFG DIS
rw
rw
7
Reset value: 00F0H
9
8
6
5
4
3
2
1
SLA
VE
ARB
EN
CSPEN
SAPEN
rw
rw
rw
rw
0
The EBC Mode Register 0 controls the alternate function of the pins.
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Field
RDYPOL
RDYDIS
ALEDIS
BYTDIS
WRCFG2)
EBCDIS
SLAVE
ARBEN
User Manual
Bits
Typ
Description
15
rw
READY pin Polarity
14
13
12
11
10
9
8
rw
rw
rw
rw
rw
rw
rw
0
READY is active low
1
READY is active high
READY pin Disable
0
READY enabled
1
READY disabled1)
ALE pin Disable
0
ALE enabled
1
ALE disabled1)
BHE pin Disable
0
BHE enabled
1
BHE disabled1)
Configuration for pins WR/WRL, BHE/WRH
0
WR and BHE
1
WRL and WRH
EBC pins Disable
0
EBC is using the pins for external bus
1
EBC pins disabled1)
SLAVE mode enable
0
Bus arbiter acts in master mode
1
Bus arbiter acts in slave mode
BUS Arbitration Pins enable
0 HOLD, HLDA and BREQ disabled1)
1 pins act as HOLD, HLDA and BREQ
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Field
Bits
Typ
Description
CSPEN
[7:4]
rw
CS Pins Enable1)
0000
no chipselect pins enabled
0001
enables pin CS0
...
SAPEN
[3:0]
1000
enables pins CS7, ..., CS0
else
reserved
Segment Addresses Pins Enable1)
rw
0000 no segment address pin enabled
0001 enables address pin A[16]
...
1000 enables address pins A[23:16]
else
reserved
1)
disabled pins are tristate and/or usable as General Purpose IO (GPIO)
2)
A change of the bit content is not valid before the next external bus access cycle.
The EBC Mode register 1 controls the general behaviour of the EBC.
EBC Mode Register 1
EBCMOD1
XSFR
Reset value: 0000H
15
14
13
12
11
10
9
8
7
6
5
4
3
2
0
0
0
0
0
0
0
0
0
DHP
DIS
0
APDIS
r
r
r
r
r
r
r
r
r
rw
r
rw
1
0
Bits
Typ
Description
0
[15:7]
[5]
r
Reserved
The software always reads a ’0’. Although these bits are read
only, the software should always write a ’0’ in case of a write
access.
DHPDIS
[6]
rw
Data High Pins Disable
0
AD Bus Pins[15:8] enabled
1
AD Bus Pins[15:8] disabled, can be used as GPIO
APDIS1)
[4:0]
rw
Address Pins Disable
00000 Address Bus Pins [15:0] enabled
11111 Address Bus Pins [15:0] disabled, can be used as GPIO
others reserved (do not use)
1)
For a demultiplexed external bus access with the address pins disabled no address will be available.
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6.3.3
The Timing Configuration registers TCONCSx
The timing control registers are used to program the described cycle timing for the
different access phases. The timing control registers may be reprogrammed during code
fetches from the affected address window. The new settings are first valid for the next
access.
Timing Configuration Register for Chip Select Channel 0
TCONCS0
XSFR
13
12
11
10
9
8
7
6
5
Reset value: 6243H
15
14
4
3
0
WRPHF
RDPHF
PHE
PHD
PHC
PHB
PHA
r
rw
rw
rw
rw
rw
rw
rw
Timing Configuration Register for Chip Select Channel x
TCONCSx
XSFR
13
12
11
10
9
8
7
6
5
2
1
0
Reset value: 0000H
15
14
4
3
2
1
0
0
WRPHF
RDPHF
PHE
PHD
PHC
PHB
PHA
r
rw
rw
rw
rw
rw
rw
rw
x = 1 ... 7
For controlling accesses to the monitor memory and start up memory there are two
timing control registers TCONCSMM and TCONCSSM. The functional control selection
and address windows are fixed and not changeable for the built-in memories.
Timing Configuration Register for Chip Select Monitor Memory
TCONCSMM
XSFR
Reset value: 6243H
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
WRPHF
RDPHF
PHE
PHD
PHC
PHB
PHA
r
rw
rw
rw
rw
rw
rw
rw
Timing Configuration Register for Chip Select Startup Memory
TCONCSSM
XSFR
Reset value: 6243H
15
14
13
0
WRPHF
RDPHF
PHE
PHD
PHC
PHB
PHA
r
rw
rw
rw
rw
rw
rw
rw
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Field
Bits
Typ
Description
0
15
r
Reserved
The software always reads a ’0’. Although this bit is
read only, the software should always write a ’0’ in
case of a write access.
WRPHF
[14:13] rw
Write Phase F
00
0 clock cycles
...
11
RDPHF
[12:11] rw
3 clock cycles
Read Phase F
00
0 clock cycles
...
11
PHE
[10:6]
rw
3 clock cycles
Phase E
00000
1 clock cycle
...
11111
PHD
PHC
5
[4:3]
rw
rw
32 clock cycles
Phase D
0
0 clock cycles
1
1 clock cycle
Phase C
00
0 clock cycles
...
11
PHB
PHA
2
[1:0]
rw
rw
3 clock cycles
Phase B
0
1 clock cycle
1
2 clock cycles
Phase A
00
0 clock cycles
...
11
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6.3.4
The Function Configuration Registers FCONCSx
The Function Control registers are used to control the bus and ready functionality for a
selected address window. It can be distinguished between 8 and 16 bit bus and
multiplexed and demulitplexed accesses. Furthermore the READY functionality can be
programmed and defined whether the address window is enabled or not.
Function Configuration Register for Chip Select Channel 0
FCONCS0
XSFR
5
4
Reset value: 0021H
15
14
13
12
11
10
9
8
7
6
0
0
0
0
0
0
0
0
0
0
BTYP
0
r
r
r
r
r
r
r
r
r
r
rw
r
Function Configuration Register for Chip Select Channel x
FCONCSx
XSFR
5
4
3
2
1
RDY RDY
MOD EN
rw
rw
0
EN
CS
rw
Reset value: 0000H
15
14
13
12
11
10
9
8
7
6
3
0
0
0
0
0
0
0
0
0
0
BTYP
0
r
r
r
r
r
r
r
r
r
r
rw
r
2
1
RDY RDY
MOD EN
rw
rw
0
EN
CS
rw
x = 1 ... 7
Field
Bits
Typ
Description
0
[15:6]
r
Reserved
The software always reads a ’0’. Although these
bits are read only, the software should always
write a ’0’ in case of a write access.
BTYP
[5:4]
rw
Bus Type Selection
0
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3
r
00
8 bit Demultiplexed
01
8 bit Multiplexed
10
16 bit Demultiplexed
11
16 bit Multiplexed
Reserved
The software always reads a ’0’. Although this bit
is read only, the software should always write a ’0’
in case of a write access.
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Field
Bits
Typ
Description
RDYMOD
2
rw
Ready Mode
RDYEN
1
rw
0
asynchronous READY
1
synchronous READY
Ready enable
0
access time is controlled by bitfield PHEx
1
access time is controlled by bitfield PHEx
and READY signal
ENCS1)
1)
0
rw
Enable Chip Select
0
disable
1
enable
Disabling a Chip Select not only effects the chip select output signal; it also deactivates the respective address
window of the disabled chip select. A disabled address window is also ignored by an address window
arbitration (see Chapter 6.3.5.2).
6.3.5
The Address Window Selection Registers ADDRSELx
Address range and size Select for Chip Select Channel x
ADDRSELx
XSFR
15
14
13
12
11
10
9
8
7
6
5
Reset value: 0000H
4
3
2
1
RGSAD
RGSZ
rw
rw
0
x = 1 ... 7
Field
Bits
Typ
Description
RGSAD
[15:4]
rw
Address Range Start Address Selection
RGSZ
[3:0]
rw
Address Range Size Selection (see Table 6-2)
Note: There is no register ADDRSEL0, as register set FCONCS0 / TCONCS0 controls
all external accesses outside the seven address windows built by the seven
address selects ADDRSEL1 to ADDRSEL7.
6.3.5.1
Definition of Address Areas
The seven register sets FCONCS1/TCONCS1/ADDRSEL1 to FCONCS7/TCONCS7/
ADDRSEL7 define seven separate address areas within the address space of the
C166S V2. Within each of these address areas external accesses can be driven in one
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of the four different bus modes independently. Each ADDRSELx register cuts out an
address window, where the corresponding parameters of the registers FCONCSx and
TCONCSx are used to control external accesses. The range start address of such a
window defines the most significant address bits of the selected window which are
consequently not needed to address the memory/module in this window (Table 6-2).
The size of the window chosen by ADDRSELx.RGSZ defines the relevant bits of
ADDRSELx.RGSAD (marked with ‘R’) which are used to select with the most significant
bits of the request address the corresponding window. The other bits of the request
address are used to address the memory locations inside this window. The lower bits of
ADDRSELx.RGSAD (marked ‘x’) are disregarded.
Two additional chip select channels, which are used for accessing the startup and the
monitor memory, are located in a predefined address range. The size of these two
address areas is fixed to 32 kByte.
The address area from 00’8000H to 00’FFFFH (32 kbyte) is reserved for C166S V2 CPU
internal I/O, the area from BF’0000H to BF’FFFFH (64 kbyte) for startup and monitor
memory and the area from C0’0000H to FF’FFFFH (4 Mbyte) is used by the internal
program memory. Therefore, these address areas cannot be used by external resources
connected to the external bus.
Table 6-2
Address range and size for ADDRSELx
ADDRSELx
Address Window
Range
Size
RGSZ
Relevant (R) bits
of RGSAD
3..0
15
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
11xx
RRRR
RRRR
RRRR
RRRR
RRRR
RRRR
RRRR
RRRR
RRRR
RRRx
RRxx
Rxxx
xxxx
1)
...
4
RRRR
RRRR
RRRR
RRRR
RRRR
RRRx
RRxx
Rxxx
xxxx
xxxx
xxxx
xxxx
xxxx
RRRR
RRRx
RRxx
Rxxx
xxxx
xxxx
xxxx
xxxx
xxxx
xxxx
xxxx
xxxx
xxxx
Selected
Range start address A[23:0]
address range selected with R-bits of RGSAD
size
4 KBytes
8 KBytes
16 KBytes
32 KBytes
64 KBytes
128 KBytes
256 KBytes
512 KBytes
1 MBytes
2 MBytes
4 MBytes
8 MBytes
reserved1)
A23
RRRR
RRRR
RRRR
RRRR
RRRR
RRRR
RRRR
RRRR
RRRR
RRR0
RR00
R000
----
...
RRRR
RRRR
RRRR
RRRR
RRRR
RRR0
RR00
R000
0000
0000
0000
0000
----
RRRR
RRR0
RR00
R000
0000
0000
0000
0000
0000
0000
0000
0000
----
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
----
A0
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
----
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
0000
----
The complete address space of 12 MByte can be selected by the default chip select CS0.
Note: The range start address can only be on boundaries specified by the selected
range size according to Table 6-2.
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6.3.5.2
Address Window Arbitration
For each external access the EBC compares the current address with all address select
registers (programmable ADDRSELx and hardwired address select registers for startup
and monitor memory) of enabled windows. This comparison is done in four levels.
Priority 1: The hardwired address select registers for startup and monitor memories
are evaluated first. A match with one of these two address ranges directs
the access to the respective memory using the corresponding chip select
with its timing control register. The window of monitor and start up is not
accessible by other chip selects.
Priority 2: Registers ADDRSELx [x = 2, 4, 6] are evaluated first. A window match with
one of these registers directs the access to the respective external area
using the corresponding set of control registers FCONCSx/TCONCSx and
ignoring registers ADDRSELy. An overlapping of windows of this group will
lead to an undefined behaviour.
Priority 3: A match with registers ADDRSELy [y = 1, 3, 5, 7] directs the access to the
respective external area using the corresponding set of control registers
FCONCSy/TCONCSy. An overlapping of windows of this group will lead to
an undefined behaviour. Overlaps with priority 2 ADDRSELx are only
allowed for the (x,y) pairs (2,1), (4,3) and (6,5).
Priority 4: If there is no match with any address select register (neither the hardwired
ones nor the programmable ADDRSEL) the access to the external bus uses
the general set of control registers FCONCS0/TCONCS0 if enabled.
Active Window
Not external addressable Window
Window reserved for Startup and
Monitor
Inactive Window
CS2
CSSM CSMM
1
CS6
CS4
2
CS1
CS5
CS3
Priority
Priority
2
CS7
3
3
CS0
Figure 6-5
internal program
memory
1000000 H
C00000 H
H
startup and
trace memory
segment 191
BF000
0
internal I/O
010000 H
008000 H
4
000000 H
4
Address Window Arbitration
Note: Only the indicated overlaps are allowed. All other overlaps lead to erroneous bus
cycles. E.g. ADDSEL4 may not overlap ADDRSEL2 or ADDRSEL1. The
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hardwired address ranges for the startup memory and the monitor memory are
defined non-overlapping.
6.3.6
Ready Controlled Bus Cycles
6.3.6.1
General
For situations, where the response (access) time of a peripheral is not constant, or where
the programmable wait states are not enough, the C166S V2 EBC provides external bus
cycles that are terminated via a READY input signal. In this case during phase E the
C166S V2 EBC first counts a programmable number of clock cycles (1...32) and starts
in the last wait cycle to monitor the internal READY line (see Figure 6-6) to determine
the actual end of the current bus cycle. The external device drives READY active in order
to indicate that data has been latched (write cycle) or is available (read cycle).
The READY pin is generally enabled by setting the bit RDYDIS in EBCMOD0 to ’0’ in
order to switch the corresponding port pin. Also the polarity of the READY is defined
inside the EBCMOD0 register on the RDYPOL bit.
For a specific access the READY function is enabled via the RDYEN bit in the FCONCSx
registers. With FCONCSx.RDYMOD the READY is handled either in synchronous or in
asynchronous mode (see also Figure 6-6).
When the READY function is enabled for a specific address window, each bus cycle
within this window must be terminated with an active READY signal. Otherwise the
controller hangs until the next reset. This is also the case for an enabled RDYEN but a
disabled READY port pin.
async.
0
0
READY ext
sync
1
User Manual
1
FCONCSx.RDYMODx
EBCMOD0.RDYPOL
Figure 6-6
READY int
External to internal READY conversion
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6.3.6.2
The Synchronous/Asynchronous READY
The synchronous READY provides the fastest bus cycles, but requires setup and hold
times to be met. The CLKOUT signal should be enabled and may be used by the
peripheral logic to control the READY timing in this case.
The asynchronous READY is less restrictive, but requires one additional wait state
caused by the internal synchronization. As the asynchronous READY is sampled earlier
programmed wait states may be necessary to provide proper bus cycles
A READY signal (especially asynchronous READY) that has been activated by an
external device may be deactivated in response to the trailing (rising) edge of the
respective command (RD or WR).
Bus Cycle with active READY
Bus Cycle extended via READY
programmed phase E
wait states
programmed phase E
wait states
ALE
RD/WR
sync. READY
async. READY
sampling of READY input
Figure 6-7
6.3.6.3
not interesting READY cycles
Ready controlled bus cycles
Combining the READY function with predefined wait states
Typically an external wait state or READY control logic takes a while to generate the
READY signal when a cycle was started. After a predefined number of clock cycles the
C166S V2 will start checking its READY line to determine the end of the bus cycle.
When using the READY function with so-called ‘normally-ready’ peripherals, it may lead
to erroneous bus cycles, if the READY line is sampled too early. These peripherals pull
their READY output active, while they are idle. When they are accessed, they drive
READY inactive until the bus cycle is complete, then drive it active again. If, however,
the peripheral drives READY inactive a little late, after the first sample point of the
C166S V2, the controller samples an active READY and terminates the current bus cycle
too early. By inserting predefined wait states the first READY sample point can be shifted
to a time, where the peripheral has safely controlled the READY line.
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6.3.7
EBC Idle State
When the external bus interface is enabled, but no external access is currently executed,
the EBC is idle. As long as only internal resources (from a CPU point of view) like RAM,
peripherals or registers, etc. are used, the external bus interface remains unchanged
(see Table 6-3). The external control signals (RD and WR or WRL/WRH if enabled)
remain inactive (high).
Table 6-3
Status of the External Bus Interface during EBC Idle State
Pins
Internal accesses only
AD15 to AD0
Tristate (floating)
A15 to A0
Undefined address (if used for the bus interface)
A23 to A16
Undefined segment address (on selected pins)
CS7 to CS0
Inactive (high)
BHE
Level corresponding to last external access
ALE
Inactive (low)
RD
Inactive (high)
WR/WRL
Inactive (high)
WRH
Inactive (high)
6.4
Multi Master Systems
6.4.1
External Bus Arbitration
The C166S V2 supports multi master systems on the external bus by its external bus
arbitration. This bus arbitration allows an external master to request the C166S V2’s bus.
The C166S V2 will release the external bus and will float the data and address bus lines
and force the control signals via pull ups/downs to their inactive state.
6.4.1.1
Initialization of Arbitration
During reset all arbitration pins are tristate, except pin BREQ which is pulled inactive.
After reset the C166S V2 EBC always starts in ‘init mode’ where the external bus is
available but no arbitration is enabled. All arbitration pins are ignored in this state. Other
to the external bus connected C166S V2 EBCs assume to have the bus also, so
potential bus conflicts are not resolved. For a multimaster system the arbitration should
be initialized first before starting any bus access. The EBC can either be chosen as
arbitration master or as arbitration slave by programming the EBCMOD0 bit SLAVE. The
selected mode and the arbitration gets active by the first setting of the HLDEN bit inside
the CPUs PSW register. Afterwards a change of the slave/master mode is not possible
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without resetting the device. Of course for arbitration the dedicated pins have to be
activated by setting EBCMOD0.ARBEN.
6.4.1.2
Arbitration Master Scheme
If the C166S V2 EBC is configured as arbitration master, it is default owner of the
external bus, controls the arbitration protocol and drives the bus also during idle phases
with no bus requests. To perform the arbitration handshake a HOLD input allows the
request of the external bus from the arbitration master. When the arbitration master
hands over the bus to the requester this is signaled by driving the hold acknowledge pin
HLDA low, which remains at this level until the arbitration slave frees the bus by releasing
its request on the HOLD input. If the arbitration master is not the owner of the bus it treats
the external bus interface as follows:
•
•
•
•
Address and data bus(es) float to tristate
Command lines are pulled high by internal pull-up devices (RD, WR/WRL, BHE/WRH)
Address latch control line ALE is pulled low by an internal pull-down device
CSx outputs are pulled high by internal pull-up devices.
In this state the arbitration slave can take over the bus.
If the arbitration master requires the bus again, it can request the bus via the bus request
signal BREQ. As soon as the arbitration master regains the bus it releases the BREQ
signal and drives HLDA to high.
not fixed number of cycles (0 ... n)
HOLD
HLDA
earliest change
BREQ
CSx,WRH
pull up
WR/WRL, RD
not active driven
ADD, DATA
BHE
Figure 6-8
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high impedance
Releasing the Bus by the Arbitration Master
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Note: The figure above shows the first possibility for BREQ to get active. The C166S V2
will complete the currently running bus cycle before granting the external bus as
indicated by the broken lines.
Figure 6-9
Regaining the Bus by the Arbitration Master
HOLD
HLDA
no BREQ request
BREQ
latest possible change
CSx,WRH
WR/WRL, RD
ADD, BHE
pull up
not active driven
high impedance
Note: The falling BREQ edge shows the last chance for BREQ to trigger the indicated
regain-sequence. Even if BREQ is activated earlier the regain-sequence is
initiated by HOLD going high. Please note that HOLD may also be deactivated
without the C166S V2 requesting the bus.
6.4.1.3
Arbitration Slave Scheme
If the C166S V2 EBC is configured as arbitration slave it is by default not owner of the
external bus and has to request the bus first. As long as it has not finished all its queued
requests and the arbitration master is not requesting the bus the arbitration slave stays
owner of the bus. For the description of the signal handling of the handshake see
Chapter 6.4.1.2. For the arbitration slave the hold acknowledge pin HLDA is configured
as input.
6.4.1.4
Locking the Bus
If an application in a multimaster system requires a sequence of undisturbed bus access
it has the possibility (independently of being arbitration slave or master) to lock1) the bus
1)
It is not allowed to lock the bus by resetting the EBCMOD0.ARBEN bit, as this can lead to bus conflicts.
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by setting the PSW bit HLDEN to ‘0’. In this case the looked C166S V2 EBC will not
answer to HOLD requests from other external bus master until HLDEN is set to ‘1’ again.
Of course a looked bus master not owning the bus can request the external bus. If a
master and a slave are requesting the external bus at the same time for several
accesses, they toggle the ownership after each access cycle if the bus is not locked.
6.4.2
Connecting Multimaster Systems
HOLD
HOLD
HLDA
HLDA
BREQ
BREQ
C166S V2 in
Slave Mode
C166S V2 in
Master Mode
Two C166S V2s where one is configured as arbitration master and the other as
arbitration slave can be connected directly together as shown in Figure 6-10. As both
EBCs assume after reset to own the external bus, the ‘slave’ CPU has to be released
from reset and initialized first, before starting the ‘master’ CPU. The other way is to start
both systems at the same time but then both EBC must be configured and the
PSW.HLDEN bits set before the first external bus request.
Figure 6-10 Connecting two C166S V2s using Master/Slave Arbitration
When more than two C166S V2s or other compatible bus masters are connected
together additional interconnection/arbitration logic is required. In this case the slave/
master selection has to be done according to the introduced logic.
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External Bus Controller
6.5
Fastest possible external access
The following four figures show the principal possible fastest access type for the EBC.
Figure 6-11
Fastest Read Cycle Demultiplexed Bus
b
e
CLK
ALE
valid
ADDR, CS
RD
valid
DATA in
Figure 6-12
Fastest Write Cycle Demultiplexed Bus
b
e
CLK
ALE
valid
ADDR, CS
WR
valid
DATA out
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External Bus Controller
Figure 6-13
Fastest Read Cycle Multiplexed Bus
b
e
f
CLK
ALE
valid
ADDR, CS
RD
muxed Address out / DATA in
Figure 6-14
add valid
d.valid
Fastest Write Cycle Multiplexed Bus
e
b
CLK
ALE
valid
ADDR, CS
WR
muxed Address out / DATA out
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addr valid valid
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C166S V2
Instruction Set
7
Instruction Set
7.1
Short Instruction Summary
The following compressed cross-reference tables quickly identify specific instructions
and provide basic information about them Two ordering schemes are included:
The first table (two pages) is a compressed cross-reference table that quickly associates
specific hexadecimal opcodes with the corresponding mnemonics.
The second table lists instructions by their mnemonic and identifies the addressing
modes that may be used with the specific instructions and indicates the instruction length
for the selected addressing mode. This reference helps to optimize instruction
sequences in terms of code size and/or execution time.
Description Levels
In the following sections the instructions are compiled according to different criteria in
order to provide different levels of precision:
• Cross Reference Tables summarize all instructions in condensed tables
• The Instruction Set Summary groups the individual instructions into functional
groups
• The Opcode Table references the instructions by their hexadecimal opcode
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Instruction Set
0x
1x
2x
3x
4x
5x
6x
7x
x0 ADD
ADDC
SUB
SUBC
CMP
XOR
AND
OR
x1 ADDB
ADDCB
SUBB
SUBCB
CMPB
XORB
ANDB
ORB
x2 ADD
ADDC
SUB
SUBC
CMP
XOR
AND
OR
x3 ADDB
ADDCB
SUBB
SUBCB
CMPB
XORB
ANDB
ORB
x4 ADD
ADDC
SUB
SUBC
-
XOR
AND
OR
x5 ADDB
ADDCB
SUBB
SUBCB
-
XORB
ANDB
ORB
x6 ADD
ADDC
SUB
SUBC
CMP
XOR
AND
OR
x7 ADDB
ADDCB
SUBB
SUBCB
CMPB
XORB
ANDB
ORB
x8 ADD
ADDC
SUB
SUBC
CMP
XOR
AND
OR
x9 ADDB
ADDCB
SUBB
SUBCB
CMPB
XORB
ANDB
ORB
xA BFLDL
BFLDH
BCMP
BMOVN BMOV
BOR
BAND
BXOR
xB MUL
MULU
PRIOR
-
DIV
DIVU
DIVL
DIVLU
xC ROL
ROL
ROR
ROR
SHL
SHL
SHR
SHR
xD JMPR
JMPR
JMPR
JMPR
JMPR
JMPR
JMPR
JMPR
xE BCLR
BCLR
BCLR
BCLR
BCLR
BCLR
BCLR
BCLR
xF BSET
BSET
BSET
BSET
BSET
BSET
BSET
BSET
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Instruction Set
8x
9x
Ax
Bx
Cx
Dx
x0 CMPI1
CMPI2
CMPD1
CMPD2
MOVBZ
MOVBS MOV
MOV
x1 NEG
CPL
NEGB
CPLB
-
AT/
EXTR
MOVB
x2 CMPI1
CMPI2
CMPD1
CMPD2
MOVBZ
MOVBS PCALL
MOV
x3 CoXXX
CoXXX
CoXXX
Co
STORE
Co
STORE
CMOV
-
MOVB
x4 MOV
MOV
MOVB
MOVB
MOV
MOV
MOVB
MOVB
x5 ENWDT -
DIS
WDT
EINIT
MOVBZ
MOVBS -
-
x6 CMPI1
CMPI2
CMPD1
CMPD2
SCXT
SCXT
MOV
x7 IDLE
PWRDN SRV
WDT
SRST
-
EXTP/S/ MOVB
R
MOVB
x8 MOV
MOV
MOV
MOV
MOV
MOV
MOV
-
x9 MOVB
MOVB
MOVB
MOVB
MOVB
MOVB
MOVB
-
xA JB
JNB
JBC
JNBS
CALLA
CALLS
JMPA
JMPS
xB -
TRAP
CALLI
CALLR
RET
RETS
RETP
RETI
xC SBRK
JMPI
ASHR
ASHR
NOP
EXTP/S/ PUSH
R
POP
xD JMPR
JMPR
JMPR
JMPR
JMPR
JMPR
JMPR
JMPR
xE BCLR
BCLR
BCLR
BCLR
BCLR
BCLR
BCLR
BCLR
xF BSET
BSET
BSET
BSET
BSET
BSET
BSET
BSET
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Fx
MOVB
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C166S V2
Instruction Set
7.2
Instruction Set Summary
This section summarizes the instructions and lists them by functional class. This enables
quick identification of the right instruction(s) for a specific function.
The following notes apply to this summary:
Data Addressing Modes
Rw:
–
Word GPR (R0, R1, … , R15)
Rb:
–
Byte GPR (RL0, RH0, …, RL7, RH7)
IDX:
–
Address Pointer IDX (IDX0, IDX1)
QX:
–
Address Offset Register QX (QX0, QX1)
QR:
–
Address Offset Register QR (QR0, QR1)
reg:
–
SFR or GPR
(in case of a byte operation on an SFR, only the low byte can be
accessed via ‘reg’)
mem:
–
Direct word or byte memory location
[…]:
–
Indirect word or byte memory location
(Any word GPR can be used as indirect address pointer, except for the
arithmetic, logical and compare instructions, where only R0 to R3 are
allowed)
bitaddr:
–
Direct bit in the bit-addressable memory area
bitoff:
–
Direct word in the bit-addressable memory area
#data:
–
Immediate constant
(The number of significant bits which can be specified by the user is
represented by the respective appendix ’x’)
#mask8: –
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Immediate 8-bit mask used for bit-field modifications
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Instruction Set
Table 7-1 shows the various combinations of pointer post-modification for the
addressing modes of the CoXXX instructions. The symbols “[Rwn*∗]” and “[IDXi∗]” will be
used to refer to these addressing modes.
Table 7-1
Pointer Post-Modification Combinations for IDXi and Rwn
Symbol
Mnemonic
Address Pointer Operation
“[IDXi⊗]” stands for
[IDXi]
(IDXi) ← (IDXi) (no-operation)
[IDXi+]
(IDXi) ← (IDXi) +2 (i=0,1)
[IDXi -]
(IDXi) ← (IDXi) -2 (i=0,1)
[IDXi + QXj]
(IDXi) ← (IDXi) + (QXj) (i, j =0,1)
[IDXi - QXj]
(IDXi) ← (IDXi) - (QXj) (i, j =0,1)
[Rwn]
(Rwn) ← (Rwn) (no-operation)
[Rwn+]
(Rwn) ← (Rwn) +2 (n=0-15)
[Rwn-]
(Rwn) ← (Rwn) -2 (n=0-15)
[Rwn+QRj]
(Rwn) ← (Rwn) + (QRj) (n=0-15;j =0,1)
[Rwn - QRj]
(Rwn) ← (Rwn) - (QRj) (n=0-15; j =0,1)
“[Rwn⊗]” stands for
Multiply and Divide Operations
The MDL and MDH registers are implicit source and/or destination operands of the
multiply and divide instructions.
Branch Target Addressing Modes
caddr:
–
Direct 16-bit jump target address (Updates the Instruction Pointer)
seg:
–
Direct 2-bit segment address
(Updates the Code Segment Pointer)
rel:
–
Signed 8-bit jump target word offset address relative to the Instruction
Pointer of the following instruction
#trap7:
–
Immediate 7-bit trap or interrupt number.
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Instruction Set
Extension Operations
The EXT* instructions override the standard DPP addressing scheme:
#pag10:
–
Immediate 10-bit page address.
#seg8:
–
Immediate 8-bit segment address.
Branch Condition Codes
cc:
Symbolically specifiable condition codes
cc_UC
cc_Z
cc_NZ
cc_V
cc_NV
cc_N
cc_NN
cc_C
cc_NC
cc_EQ
cc_NE
cc_ULT
cc_ULE
cc_UGE
cc_UGT
cc_SLE
cc_SGE
cc_SGT
cc_NET
cc_nusr0
cc_nusr1
cc_usr0
cc_usr1
1)
–Unconditional
–Zero
–Not Zero
–Overflow
–No Overflow
–Negative
–Not Negative
–Carry
–No Carry
–Equal
–Not Equal
–Unsigned Less Than
–Unsigned Less Than or Equal
–Unsigned Greater Than or Equal
–Unsigned Greater Than
–Signed Less Than or Equal
–Signed Greater Than or Equal
–Signed Greater Than
–Not Equal and Not End-of-Table
–USR-bit 0 is cleared1)
–USR-bit 1 is cleared1)
–USR-bit 0 is set1)
–USR-bit 1 is set1)
Only usable with the JMPA and CALLA instructions
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Instruction Set
Mnemonic
ADD[B]
ADDC[B]
AND[B]
OR[B]
SUB[B]
SUBC[B]
XOR[B]
Addressing ModesBytes
Rwn
Rwm
Rwn
[Rwi]
Rwn
[Rwi+]
Rwn
#data3
reg
reg
mem
#data16
mem
reg
4
4
4
ASHR
ROL / ROR
SHL / SHR
BAND
BCMP
BMOV
BMOVN
BOR /
BXOR
BCLR
BSET
BFLDH
BFLDL
MOV[B]
Rwn
Rwn
Rwm
#data4
2
2
Mnemonic
CPL[B]
NEG[B]
DIV
DIVL
DIVLU
DIVU
MUL
MULU
CMPD1/2
CMPI1/2
bitaddrZ.z
bitaddrQ.q
4
CMP[B]
2
CALLA
JMPA
CALLI
JMPI
CALLS
JMPS
CALLR
JMPR
JB
JBC
JNB
JNBS
PCALL
POP
PUSH
RETP
SCXT
MOVBS
MOVBZ
EXTS
EXTSR
NOP
RET
RETI
RETS
SBRK
1)
2)
1)
1)
1)
1)
bitaddrQ.q
2
2
2
2
bitoffQ
#mask8 #data8 4
Rwn
Rwn
Rwn
Rwn
[Rwm]
[-Rwm]
[Rwn]
[Rwn+]
[Rwn]
Rwm
#data4
[Rwm]
[Rwm+]
Rwn
Rwn
[Rwm]
[Rwm]
[Rwm+]
1)
1)
1)
1)
1)
1)
2
2
2
2
2
2
2
2
2
reg
Rwn
[Rwm+#d16]
[Rwn]
mem
reg
mem
Rwn
reg
mem
#data16
[Rwm+#d16]
Rwn
mem
[Rwn]
mem
reg
Rbm
mem
reg
2)
1)
1)
4
4
4
4
4
4
4
2
4
4
Rwm
#seg
-
#irang2
#irang2
2
4
2
PRIOR
TRAP
ATOMIC
EXTR
EXTP
EXTPR
SRST/IDLE
PWRDN
SRVWDT
DISWDT
ENWDT
EINIT
Addressing ModesBytes
Rwn
1)
Rwn
2
2
Rwn
Rwm
2
Rwn
Rwn
Rwn
Rwn
Rwn
Rwn
Rwn
reg
reg
cc
#data4
#data16
mem
Rwm
[Rwi]
[Rwi+]
#data3
#data16
mem
caddr
2
4
4
2
2
2
2
4
4
4
cc
[Rwn]
2
seg
caddr
4
rel
cc
bitaddrQ.q
rel
rel
2
2
4
1)
1)
1)
1)
2)
reg
reg
caddr
4
2
reg
reg
Rwn
#data16
mem
Rwm
4
4
2
#trap7
#irang2
Rwm
#pag
-
2
2
#irang2
#irang2
2
4
4
Byte oriented instructions (suffix ‘B’) use Rb instead of Rw (not with [Rwn]!).
Byte oriented instructions (suffix ‘B’) use #data8 instead of #data16.
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Instruction Set
Instruction Set Summary
Mnemonic
Description
Bytes
Arithmetic Operations
ADD
Rw, Rw
Add direct word GPR to direct GPR
2
ADD
Rw, [Rw]
Add indirect word memory to direct GPR
2
ADD
Rw, [Rw +]
Add indirect word memory to direct GPR and postincrement source pointer by 2
2
ADD
Rw, #data3
Add immediate word data to direct GPR
2
ADD
reg, #data16
Add immediate word data to direct register
4
ADD
reg, mem
Add direct word memory to direct register
4
ADD
mem, reg
Add direct word register to direct memory
4
ADDB
Rb, Rb
Add direct byte GPR to direct GPR
2
ADDB
Rb, [Rw]
Add indirect byte memory to direct GPR
2
ADDB
Rb, [Rw +]
Add indirect byte memory to direct GPR and
post-increment source pointer by 1
2
ADDB
Rb, #data3
Add immediate byte data to direct GPR
2
ADDB
reg, #data8
Add immediate byte data to direct register
4
ADDB
reg, mem
Add direct byte memory to direct register
4
ADDB
mem, reg
Add direct byte register to direct memory
4
ADDC
Rw, Rw
Add direct word GPR to direct GPR with Carry
2
ADDC
Rw, [Rw]
Add indirect word memory to direct GPR with Carry
2
ADDC
Rw, [Rw +]
Add indirect word memory to direct GPR with Carry and
post-increment source pointer by 2
2
ADDC
Rw, #data3
Add immediate word data to direct GPR with Carry
2
ADDC
reg, #data16
Add immediate word data to direct register with Carry
4
ADDC
reg, mem
Add direct word memory to direct register with Carry
4
ADDC
mem, reg
Add direct word register to direct memory with Carry
4
ADDCB
Rb, Rb
Add direct byte GPR to direct GPR with Carry
2
ADDCB
Rb, [Rw]
Add indirect byte memory to direct GPR with Carry
2
ADDCB
Rb, [Rw +]
Add indirect byte memory to direct GPR with Carry and
post-increment source pointer by 1
2
ADDCB
Rb, #data3
Add immediate byte data to direct GPR with Carry
2
ADDCB
reg, #data8
Add immediate byte data to direct register with Carry
4
ADDCB
reg, mem
Add direct byte memory to direct register with Carry
4
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Instruction Set
Instruction Set Summary (cont’d)
Mnemonic
Description
Bytes
Arithmetic Operations (cont’d)
ADDCB
mem, reg
Add direct byte register to direct memory with Carry
4
SUB
Rw, Rw
Subtract direct word GPR from direct GPR
2
SUB
Rw, [Rw]
Subtract indirect word memory from direct GPR
2
SUB
Rw, [Rw +]
Subtract indirect word memory from direct GPR and
post-increment source pointer by 2
2
SUB
Rw, #data3
Subtract immediate word data from direct GPR
2
SUB
reg, #data16
Subtract immediate word data from direct register
4
SUB
reg, mem
Subtract direct word memory from direct register
4
SUB
mem, reg
Subtract direct word register from direct memory
4
SUBB
Rb, Rb
Subtract direct byte GPR from direct GPR
2
SUBB
Rb, [Rw]
Subtract indirect byte memory from direct GPR
2
SUBB
Rb, [Rw +]
Subtract indirect byte memory from direct GPR and
post-increment source pointer by 1
2
SUBB
Rb, #data3
Subtract immediate byte data from direct GPR
2
SUBB
reg, #data8
Subtract immediate byte data from direct register
4
SUBB
reg, mem
Subtract direct byte memory from direct register
4
SUBB
mem, reg
Subtract direct byte register from direct memory
4
SUBC
Rw, Rw
Subtract direct word GPR from direct GPR with Carry
2
SUBC
Rw, [Rw]
Subtract indirect word memory from direct GPR with Carry
2
SUBC
Rw, [Rw +]
Subtract indirect word memory from direct GPR with
Carry and post-increment source pointer by 2
2
SUBC
Rw, #data3
Subtract immediate word data from direct GPR with Carry
2
SUBC
reg, #data16
Subtract immediate word data from direct register with
Carry
4
SUBC
reg, mem
Subtract direct word memory from direct register with Carry 4
SUBC
mem, reg
Subtract direct word register from direct memory with Carry 4
SUBCB
Rb, Rb
Subtract direct byte GPR from direct GPR with Carry
2
SUBCB
Rb, [Rw]
Subtract indirect byte memory from direct GPR with Carry
2
SUBCB
Rb, [Rw +]
Subtract indirect byte memory from direct GPR with Carry
and post-increment source pointer by 1
2
SUBCB
Rb, #data3
Subtract immediate byte data from direct GPR with Carry
2
SUBCB
reg, #data8
Subtract immediate byte data from direct register with Carry 4
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Instruction Set
Instruction Set Summary (cont’d)
Mnemonic
Description
Bytes
Arithmetic Operations (cont’d)
SUBCB
reg, mem
Subtract direct byte memory from direct register with Carry
4
SUBCB
mem, reg
Subtract direct byte register from direct memory with Carry
4
MUL
Rw, Rw
Signed multiply direct GPR by direct GPR (16-16-bit)
2
MULU
Rw, Rw
Unsigned multiply direct GPR by direct GPR (16-16-bit)
2
DIV
Rw
Signed divide register MDL by direct GPR (16-/16-bit)
2
DIVL
Rw
Signed long divide register MD by direct GPR (32-/16-bit)
2
DIVLU
Rw
Unsigned long divide register MD by direct GPR
(32-/16-bit)
2
DIVU
Rw
Unsigned divide register MDL by direct GPR (16-/16-bit)
2
CPL
Rw
Complement direct word GPR
2
CPLB
Rb
Complement direct byte GPR
2
NEG
Rw
Negate direct word GPR
2
NEGB
Rb
Negate direct byte GPR
2
Logical Instructions
AND
Rw, Rw
Bitwise AND direct word GPR with direct GPR
2
AND
Rw, [Rw]
Bitwise AND indirect word memory with direct GPR
2
AND
Rw, [Rw +]
Bitwise AND indirect word memory with direct GPR and
post-increment source pointer by 2
2
AND
Rw, #data3
Bitwise AND immediate word data with direct GPR
2
AND
reg, #data16
Bitwise AND immediate word data with direct register
4
AND
reg, mem
Bitwise AND direct word memory with direct register
4
AND
mem, reg
Bitwise AND direct word register with direct memory
4
ANDB
Rb, Rb
Bitwise AND direct byte GPR with direct GPR
2
ANDB
Rb, [Rw]
Bitwise AND indirect byte memory with direct GPR
2
ANDB
Rb, [Rw +]
Bitwise AND indirect byte memory with direct GPR
and post-increment source pointer by 1
2
ANDB
Rb, #data3
Bitwise AND immediate byte data with direct GPR
2
ANDB
reg, #data8
Bitwise AND immediate byte data with direct register
4
ANDB
reg, mem
Bitwise AND direct byte memory with direct register
4
ANDB
mem, reg
Bitwise AND direct byte register with direct memory
4
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Instruction Set
Instruction Set Summary (cont’d)
Mnemonic
Description
Bytes
Logical Instructions (cont’d)
OR
Rw, Rw
Bitwise OR direct word GPR with direct GPR
2
OR
Rw, [Rw]
Bitwise OR indirect word memory with direct GPR
2
OR
Rw, [Rw +]
Bitwise OR indirect word memory with direct GPR
and post-increment source pointer by 2
2
OR
Rw, #data3
Bitwise OR immediate word data with direct GPR
2
OR
reg, #data16
Bitwise OR immediate word data with direct register
4
OR
reg, mem
Bitwise OR direct word memory with direct register
4
OR
mem, reg
Bitwise OR direct word register with direct memory
4
ORB
Rb, Rb
Bitwise OR direct byte GPR with direct GPR
2
ORB
Rb, [Rw]
Bitwise OR indirect byte memory with direct GPR
2
ORB
Rb, [Rw +]
Bitwise OR indirect byte memory with direct GPR and
post-increment source pointer by 1
2
ORB
Rb, #data3
Bitwise OR immediate byte data with direct GPR
2
ORB
reg, #data8
Bitwise OR immediate byte data with direct register
4
ORB
reg, mem
Bitwise OR direct byte memory with direct register
4
ORB
mem, reg
Bitwise OR direct byte register with direct memory
4
XOR
Rw, Rw
Bitwise XOR direct word GPR with direct GPR
2
XOR
Rw, [Rw]
Bitwise XOR indirect word memory with direct GPR
2
XOR
Rw, [Rw +]
Bitwise XOR indirect word memory with direct GPR and
post-increment source pointer by 2
2
XOR
Rw, #data3
Bitwise XOR immediate word data with direct GPR
2
XOR
reg, #data16
Bitwise XOR immediate word data with direct register
4
XOR
reg, mem
Bitwise XOR direct word memory with direct register
4
XOR
mem, reg
Bitwise XOR direct word register with direct memory
4
XORB
Rb, Rb
Bitwise XOR direct byte GPR with direct GPR
2
XORB
Rb, [Rw]
Bitwise XOR indirect byte memory with direct GPR
2
XORB
Rb, [Rw +]
Bitwise XOR indirect byte memory with direct GPR and
post-increment source pointer by 1
2
XORB
Rb, #data3
Bitwise XOR immediate byte data with direct GPR
2
XORB
reg, #data8
Bitwise XOR immediate byte data with direct register
4
XORB
reg, mem
Bitwise XOR direct byte memory with direct register
4
XORB
mem, reg
Bitwise XOR direct byte register with direct memory
4
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Instruction Set
Instruction Set Summary (cont’d)
Mnemonic
Description
Bytes
Boolean Bit Manipulation Operations
BCLR
bitaddr
Clear direct bit
2
BSET
bitaddr
Set direct bit
2
BMOV
bitaddr, bitaddr
Move direct bit to direct bit
4
BMOVN
bitaddr, bitaddr
Move negated direct bit to direct bit
4
BAND
bitaddr, bitaddr
AND direct bit with direct bit
4
BOR
bitaddr, bitaddr
OR direct bit with direct bit
4
BXOR
bitaddr, bitaddr
XOR direct bit with direct bit
4
BCMP
bitaddr, bitaddr
Compare direct bit to direct bit
4
BFLDH
bitoff, #mask8,
#data8
Bitwise modify masked high byte of bit-addressable
direct word memory with immediate data
4
BFLDL
bitoff, #mask8,
#data8
Bitwise modify masked low byte of bit-addressable
direct word memory with immediate data
4
CMP
Rw, Rw
Compare direct word GPR to direct GPR
2
CMP
Rw, [Rw]
Compare indirect word memory to direct GPR
2
CMP
Rw, [Rw +]
Compare indirect word memory to direct GPR and
post-increment source pointer by 2
2
CMP
Rw, #data3
Compare immediate word data to direct GPR
2
CMP
reg, #data16
Compare immediate word data to direct register
4
CMP
reg, mem
Compare direct word memory to direct register
4
CMPB
Rb, Rb
Compare direct byte GPR to direct GPR
2
CMPB
Rb, [Rw]
Compare indirect byte memory to direct GPR
2
CMPB
Rb, [Rw +]
Compare indirect byte memory to direct GPR and
post-increment source pointer by 1
2
CMPB
Rb, #data3
Compare immediate byte data to direct GPR
2
CMPB
reg, #data8
Compare immediate byte data to direct register
4
CMPB
reg, mem
Compare direct byte memory to direct register
4
Compare and Loop Control Instructions
CMPD1
Rw, #data4
Compare immediate word data to direct GPR and
decrement GPR by 1
2
CMPD1
Rw, #data16
Compare immediate word data to direct GPR and
decrement GPR by 1
4
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C166S V2
Instruction Set
Instruction Set Summary (cont’d)
Mnemonic
Description
Bytes
Compare and Loop Control Instructions (cont’d)
CMPD1
Rw, mem
Compare direct word memory to direct GPR and
decrement GPR by 1
4
CMPD2
Rw, #data4
Compare immediate word data to direct GPR and
decrement GPR by 2
2
CMPD2
Rw, #data16
Compare immediate word data to direct GPR and
decrement GPR by 2
4
CMPD2
Rw, mem
Compare direct word memory to direct GPR and
decrement GPR by 2
4
CMPI1
Rw, #data4
Compare immediate word data to direct GPR and
increment GPR by 1
2
CMPI1
Rw, #data16
Compare immediate word data to direct GPR and
increment GPR by 1
4
CMPI1
Rw, mem
Compare direct word memory to direct GPR and
increment GPR by 1
4
CMPI2
Rw, #data4
Compare immediate word data to direct GPR and
increment GPR by 2
2
CMPI2
Rw, #data16
Compare immediate word data to direct GPR and
increment GPR by 2
4
CMPI2
Rw, mem
Compare direct word memory to direct GPR and
increment GPR by 2
4
Determine number of shift cycles to normalize direct
word GPR and store result in direct word GPR
2
Prioritize Instruction
PRIOR
Rw, Rw
Shift and Rotate Instructions
SHL
Rw, Rw
Shift left direct word GPR;
number of shift cycles specified by direct GPR
2
SHL
Rw, #data4
Shift left direct word GPR;
number of shift cycles specified by immediate data
2
SHR
Rw, Rw
Shift right direct word GPR;
number of shift cycles specified by direct GPR
2
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Instruction Set
Instruction Set Summary (cont’d)
Mnemonic
Description
Bytes
Shift and Rotate Instructions (cont’d)
SHR
Rw, #data4
Shift right direct word GPR;
number of shift cycles specified by immediate data
2
ROL
Rw, Rw
Rotate left direct word GPR;
number of shift cycles specified by direct GPR
2
ROL
Rw, #data4
Rotate left direct word GPR;
number of shift cycles specified by immediate data
2
ROR
Rw, Rw
Rotate right direct word GPR;
number of shift cycles specified by direct GPR
2
ROR
Rw, #data4
Rotate right direct word GPR;
number of shift cycles specified by immediate data
2
ASHR
Rw, Rw
Arithmetic (sign bit) shift right direct word GPR;
number of shift cycles specified by direct GPR
2
ASHR
Rw, #data4
Arithmetic (sign bit) shift right direct word GPR;
number of shift cycles specified by immediate data
2
Data Movement
MOV
Rw, Rw
Move direct word GPR to direct GPR
2
MOV
Rw, #data4
Move immediate word data to direct GPR
2
MOV
reg, #data16
Move immediate word data to direct register
4
MOV
Rw, [Rw]
Move indirect word memory to direct GPR
2
MOV
Rw, [Rw +]
Move indirect word memory to direct GPR and
post-increment source pointer by 2
2
MOV
[Rw], Rw
Move direct word GPR to indirect memory
2
MOV
[-Rw], Rw
Pre-decrement destination pointer by 2 and move direct
word GPR to indirect memory
2
MOV
[Rw], [Rw]
Move indirect word memory to indirect memory
2
MOV
[Rw +], [Rw]
Move indirect word memory to indirect memory and
post-increment destination pointer by 2
2
MOV
[Rw], [Rw +]
Move indirect word memory to indirect memory and
post-increment source pointer by 2
2
MOV
Rw,
[Rw + #data16]
Move indirect word memory by base plus constant to
direct GPR
4
MOV
[Rw + #data16],
Rw
Move direct word GPR to indirect memory by base plus
constant
4
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Instruction Set
Instruction Set Summary (cont’d)
Mnemonic
Description
Bytes
Data Movement (cont’d)
MOV
[Rw], mem
Move direct word memory to indirect memory
4
MOV
mem, [Rw]
Move indirect word memory to direct memory
4
MOV
reg, mem
Move direct word memory to direct register
4
MOV
mem, reg
Move direct word register to direct memory
4
MOVB
Rb, Rb
Move direct byte GPR to direct GPR
2
MOVB
Rb, #data4
Move immediate byte data to direct GPR
2
MOVB
reg, #data8
Move immediate byte data to direct register
4
MOVB
Rb, [Rw]
Move indirect byte memory to direct GPR
2
MOVB
Rb, [Rw +]
Move indirect byte memory to direct GPR and
post-increment source pointer by 1
2
MOVB
[Rw], Rb
Move direct byte GPR to indirect memory
2
MOVB
[-Rw], Rb
Pre-decrement destination pointer by 1 and move
direct byte GPR to indirect memory
2
MOVB
[Rw], [Rw]
Move indirect byte memory to indirect memory
2
MOVB
[Rw +], [Rw]
Move indirect byte memory to indirect memory and
post-increment destination pointer by 1
2
MOVB
[Rw], [Rw +]
Move indirect byte memory to indirect memory and
post-increment source pointer by 1
2
MOVB
Rb,
[Rw + #data16]
Move indirect byte memory by base plus constant to
direct GPR
4
MOVB
[Rw + #data16],
Rb
Move direct byte GPR to indirect memory by base plus
constant
4
MOVB
[Rw], mem
Move direct byte memory to indirect memory
4
MOVB
mem, [Rw]
Move indirect byte memory to direct memory
4
MOVB
reg, mem
Move direct byte memory to direct register
4
MOVB
mem, reg
Move direct byte register to direct memory
4
MOVBS
Rw, Rb
Move direct byte GPR with sign extension to direct
word GPR
2
MOVBS
reg, mem
Move direct byte memory with sign extension to direct
word register
4
MOVBS
mem, reg
Move direct byte register with sign extension to direct
word memory
4
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Instruction Set
Instruction Set Summary (cont’d)
Mnemonic
Description
Bytes
Data Movement (cont’d)
MOVBZ
Rw, Rb
Move direct byte GPR with zero extension to direct
word GPR
2
MOVBZ
reg, mem
Move direct byte memory with zero extension to direct
word register
4
MOVBZ
mem, reg
Move direct byte register with zero extension to direct
word memory
4
Jump and Call Operations
JMPA
cc, caddr
Jump absolute if condition is met
4
JMPI
cc, [Rw]
Jump indirect if condition is met
2
JMPR
cc, rel
Jump relative if condition is met
2
JMPS
seg, caddr
Jump absolute to a code segment
4
JB
bitaddr, rel
Jump relative if direct bit is set
4
JBC
bitaddr, rel
Jump relative and clear bit if direct bit is set
4
JNB
bitaddr, rel
Jump relative if direct bit is not set
4
JNBS
bitaddr, rel
Jump relative and set bit if direct bit is not set
4
CALLA
cc, caddr
Call absolute subroutine if condition is met
4
CALLI
cc, [Rw]
Call indirect subroutine if condition is met
2
CALLR
rel
Call relative subroutine
2
CALLS
seg, caddr
Call absolute subroutine in any code segment
4
PCALL
reg, caddr
Push direct word register onto system stack and call
absolute subroutine
4
TRAP
#trap7
Call interrupt service routine via immediate trap number
2
System Stack Operations
POP
reg
Pop direct word register from system stack
2
PUSH
reg
Push direct word register onto system stack
2
SCXT
reg, #data16
Push direct word register onto system stack und update
register with immediate data
4
SCXT
reg, mem
Push direct word register onto system stack und update
register with direct memory
4
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Instruction Set
Instruction Set Summary (cont’d)
Mnemonic
Description
Bytes
RET
Return from intra-segment subroutine
2
RETS
Return from inter-segment subroutine
2
Return from intra-segment subroutine and pop direct
word register from system stack
2
Return from interrupt service subroutine
2
SRST
Software Reset
4
SBRK
Software Break
2
IDLE
Enter Idle Mode
4
PWRDN
Enter Power Down Mode
(supposes NMI-pin being low)
4
SRVWDT
Service Watchdog Timer
4
DISWDT
Disable Watchdog Timer
4
ENWDT
Enable Watchdog Timer
4
EINIT
Signify End-of-Initialization on RSTOUT-pin
4
Return Operations
RETP
reg
RETI
System Control
ATOMIC
#irang2
Begin ATOMIC sequence
*)
2
2
EXTR
#irang2
Begin EXTended Register sequence
*)
EXTP
Rw, #irang2
Begin EXTended Page sequence
*)
2
4
EXTP
#pag10, #irang2
Begin EXTended Page sequence
*)
EXTPR
Rw, #irang2
Begin EXTended Page and Register sequence
*)
2
4
EXTPR
#pag10, #irang2
Begin EXTended Page and Register sequence
*)
EXTS
Rw, #irang2
Begin EXTended Segment sequence
*)
2
4
EXTS
#seg8, #irang2
Begin EXTended Segment sequence
*)
EXTSR
Rw, #irang2
Begin EXTended Segment and Register sequence
*)
2
Begin EXTended Segment and Register sequence
*)
4
EXTSR
#seg8, #irang2
Miscellaneous
NOP
User Manual
Null operation
2
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User Manual
C166S V2
Instruction Set
7.3
Instruction Opcodes
This section lists the C166S V2 CPU instructions by hexadecimal opcodes to help
identify specific instructions when reading executable code, ie. during the debugging
phase.
Notes for Opcode Lists
• These instructions are encoded by means of additional bits in the operand field of the
instruction
x0H – x7H:
Rw, #data3 or
Rb, #data3
Rw, [Rw]
or
Rb, [Rw]
x8H – xBH:
xCH – xFH:
Rw, [Rw +] or
Rb, [Rw +]
For these instructions, only the lowest four GPRs (R0 to R3) can be used as indirect
address pointers.
• These instructions are encoded by means of additional bits in the operand field of the
instruction
00xx.xxxxB:
EXTS
or
ATOMIC
01xx.xxxxB:
EXTP
10xx.xxxxB:
EXTSR
or
EXTR
EXTPR
11xx.xxxxB:
Notes on the JMPR Instructions
The condition code to be tested for the JMPR instructions is specified by the opcode.
Two mnemonic representation alternatives exist for some of the condition codes.
Notes on the JMPA and CALLA Instructions
For JMPA+/- and CALLA+/- instructions, a static user programmable prediction scheme
is used. If bit 8 (’a’) of the instruction long word is cleared, then the branch is assumed
‘taken’. If it is set, then the branch is assumed ‘not taken’. The user controls bit 8 value
by entering ’+’ or ’-’ in the instruction mnemonics. This bit can be also set/cleared by the
Assembler for JMPA and CALLA instructions depending on the jump condition.
For JMPA instruction, a pre-fetch hint bit is used (the instruction bit 9 ’l’). This bit is
required by the fetch unit to deal efficiently with short backward loops. It must be set if 0
< IP_jmpa - IP_target <= 32, where IP_jmpa is the address of the JMPA instruction and
IP_target is the target address of the JMPA. Otherwise, bit 9 must be cleared.
Notes on the BCLR and BSET Instructions
The position of the bit to be set or cleared is specified by the opcode. The operand
‘bitoff.n’ (n = 0 to 15) refers to a particular bit within a bit-addressable word.
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C166S V2
Instruction Set
Notes on CoXXX instructions
All CoXXX instructions have a 3-bit wide extended control field ’rrr’ in the operand field
to control the MRW repeat counter. It is located within the CoXXX instructions at bit
positions [31:29].
–
–
–
–
–
‘000’
‘001’
‘010’
‘011’
’1xx’
->
->
->
->
->
regular CoXXX instruction.
RESERVED
‘- USR0 CoXXX’ instruction.
‘- USR1 CoXXX’ instruction.
RESERVED.
Notes on CoXXX instructions using indirect addressing modes
These CoXXX instructions have extended control fields in the operand field to specify
the special indirect addressing mode.
Bitfield ’X’ is 4-bits wide and is located within CoXXX instructions at bit positions [15:12].
Bit [15] specifies one of the two IDX address pointers; the bitfield [14:12] specifies the
operation concerning the IDX pointer.
Bit[15]:
– ‘0’
– ‘1’
-> IDX0
-> IDX1
Bitfield[14:12]
–
–
–
–
–
–
–
–
‘000’
‘001’
‘010’
‘011’
’100’
’101’
’110’
’111’
->
->
->
->
->
->
->
->
RESERVED
no-operation
IDX +2
IDX -2
IDX + QX0
IDX - QX0
IDX + QX1
IDX - QX1
Bitfield ’qqq’ is 3-bits wide and is located within CoXXX instructions at bit positions
[26:24]. It specifies the operation concerning the Rw pointer.
Bitfield[26:24]
–
–
–
–
–
–
–
–
‘000’
‘001’
‘010’
‘011’
’100’
’101’
’110’
’111’
->
->
->
->
->
->
->
->
User Manual
RESERVED
no-operation
Rw +2
Rw -2
Rw + QR0
Rw - QR0
Rw + QR1
Rw - QR1
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C166S V2
Instruction Set
Notes on the Undefined Opcodes
A hardware trap occurs when one of the undefined opcodes signified by ‘----’ is decoded
by the CPU.
In the following table used symbols for instruction cycle times:
reg
1 cycle, if short register addressing uses GPR
2 cycles, else
bit
1 cycle if at least one bit address is a GPR
2 cycles, else
co
1 to 2 cycle (see table for MAC instructions)
0-1
0 cycles, if branch is executed zerocycle
1 cycle, else
2-3
2 cycles, if CPUCON1.SGTDIS = 1
3 cycles, else
5-6
5 cycles, if CPUCON1.SGTDIS = 1
6 cycles, else
4+15
4 visible cycles to calculate PSW for division,
plus 15 invisible cycle where the result is not available
1-31
User Manual
1 to 31 cycles for ’multicycle’ NOP (opcode CC 000d:dddd)
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C166S V2
Instruction Set
Hexcode
Bytes/ Mnemonic
Cycles
Operands
00
01
02
03
04
2/1
2/1
4/reg
4/reg
4/reg
ADD
ADDB
ADD
ADDB
ADD
Rw, Rw
Rb, Rb
reg, mem
reg, mem
mem, reg
05
06
07
08
4/reg
4/1
4/1
2/1
ADDB
ADD
ADDB
ADD
09
2/1
ADDB
0A
4/1
BFLDL
0B
0C
0D
2/1
2/1
2/0-1
MUL
ROL
JMPR
0E
0F
10
11
12
13
14
15
16
17
18
2/1
2/1
2/1
2/1
4/reg
4/reg
4/reg
4/reg
4/1
4/1
2/1
BCLR
BSET
ADDC
ADDCB
ADDC
ADDCB
ADDC
ADDCB
ADDC
ADDCB
ADDC
19
2/1
ADDCB
1A
4/1
BFLDH
1B
1C
1D
2/1
2/1
2/0-1
1E
1F
2/1
2/1
User Manual
Hexcode
20
21
22
23
24
Bytes/ Mnemonic
Cycles
Operands
2/1
2/1
4/reg
4/reg
4/reg
SUB
SUBB
SUB
SUBB
SUB
Rw, Rw
Rb, Rb
reg, mem
reg, mem
mem, reg
mem, reg
reg, #data16
reg, #data8
Rw, [Rw +] or
Rw, [Rw] or
Rw, #data3
Rb, [Rw +] or
Rb, [Rw] or
Rb, #data3
bitoff, #mask8,
#data8
Rw, Rw
Rw, Rw
cc_UC, rel
25
26
27
28
4/reg
4/1
4/1
2/1
SUBB
SUB
SUBB
SUB
29
2/1
SUBB
2A
4/bit
BCMP
mem, reg
reg, #data16
reg, #data8
Rw, [Rw +] or
Rw, [Rw] or
Rw, #data3
Rb, [Rw +] or
Rb, [Rw] or
Rb, #data3
bitaddr, bitaddr
2B
2C
2D
2/1
2/1
2/0-1
PRIOR
ROR
JMPR
2E
2F
30
31
32
33
34
35
36
37
38
2/1
2/1
2/1
2/1
4/reg
4/reg
4/reg
4/reg
4/1
4/1
2/1
BCLR
BSET
SUBC
SUBCB
SUBC
SUBCB
SUBC
SUBCB
SUBC
SUBCB
SUBC
39
2/1
SUBCB
3A
4/bit
BMOVN
MULU
ROL
JMPR
bitoff.0
bitoff.0
Rw, Rw
Rb, Rb
reg, mem
reg, mem
mem, reg
mem, reg
reg, #data16
reg, #data8
Rw, [Rw +] or
Rw, [Rw] or
Rw, #data3
Rb, [Rw +] or
Rb, [Rw] or
Rb, #data3
bitoff, #mask8,
#data8
Rw, Rw
Rw, #data4
cc_NET, rel
3B
3C
3D
-/2/1
2/0-1
ROR
JMPR
BCLR
BSET
bitoff.1
bitoff.1
3E
3F
2/1
2/1
BCLR
BSET
7-195
Rw, Rw
Rw, Rw
cc_EQ, rel or
cc_Z, rel
bitoff.2
bitoff.2
Rw, Rw
Rb, Rb
reg, mem
reg, mem
mem, reg
mem, reg
reg, #data16
reg, #data8
Rw, [Rw +] or
Rw, [Rw] or
Rw, #data3
Rb, [Rw +] or
Rb, [Rw] or
Rb, #data3
bitaddr, bitaddr
Rw, #data4
cc_NE, rel or
cc_NZ, rel
bitoff.3
bitoff.3
V 1.7, 2001-01
User Manual
C166S V2
Instruction Set
Hexcode
40
41
42
43
44
Bytes/
Cycles
2/1
2/1
4/reg
4/reg
-/-
Mnemonic
Operands
Hexcode
60
61
62
63
64
Bytes/
Cycles
2/1
2/1
4/reg
4/reg
4/reg
Mnemonic
Operands
CMP
CMPB
CMP
CMPB
-
Rw, Rw
Rb, Rb
reg, mem
reg, mem
-
AND
ANDB
AND
ANDB
AND
Rw, Rw
Rb, Rb
reg, mem
reg, mem
mem, reg
45
46
47
48
-/4/1
4/1
2/1
CMP
CMPB
CMP
65
66
67
68
4/reg
4/1
4/1
2/1
ANDB
AND
ANDB
AND
69
2/1
ANDB
BMOV
reg, #data16
reg, #data8
Rw, [Rw +] or
Rw, [Rw] or
Rw, #data3
Rb, [Rw +] or
Rb, [Rw] or
Rb, #data3
bitaddr, bitaddr
6A
4/bit
BAND
mem, reg
reg, #data16
reg, #data8
Rw, [Rw +] or
Rw, [Rw] or
Rw, #data3
Rb, [Rw +] or
Rb, [Rw] or
Rb, #data3
bitaddr, bitaddr
49
2/1
CMPB
4A
4/bit
4B
4C
4D
2/4+15
2/1
2/0-1
DIV
SHL
JMPR
Rw
Rw, Rw
cc_V, rel
6B
6C
6D
2/4+15
2/1
2/0-1
DIVL
SHR
JMPR
Rw
Rw, Rw
cc_N, rel
4E
4F
50
51
52
53
54
55
56
57
58
2/1
2/1
2/1
2/1
4/reg
4/reg
4/reg
4/reg
4/1
4/1
2/1
BCLR
BSET
XOR
XORB
XOR
XORB
XOR
XORB
XOR
XORB
XOR
6E
6F
70
71
72
73
74
75
76
77
78
2/1
2/1
2/1
2/1
4/reg
4/reg
4/reg
4/reg
4/1
4/1
2/1
BCLR
BSET
OR
ORB
OR
ORB
OR
ORB
OR
ORB
OR
59
2/1
XORB
79
2/1
ORB
5A
4/bit
BOR
bitoff.4
bitoff.4
Rw, Rw
Rb, Rb
reg, mem
reg, mem
mem, reg
mem, reg
reg, #data16
reg, #data8
Rw, [Rw +] or
Rw, [Rw] or
Rw, #data3
Rb, [Rw +] or
Rb, [Rw] or
Rb, #data3
bitaddr, bitaddr
7A
4/bit
BXOR
bitoff.6
bitoff.6
Rw, Rw
Rb, Rb
reg, mem
reg, mem
mem, reg
mem, reg
reg, #data16
reg, #data8
Rw, [Rw +] or
Rw, [Rw] or
Rw, #data3 1)
Rb, [Rw +] or
Rb, [Rw] or
Rb, #data3
bitaddr, bitaddr
5B
5C
5D
2/4+15
2/1
2/0-1
DIVU
SHL
JMPR
Rw
Rw, #data4
cc_NV, rel
7B
7C
7D
2/4+15
2/1
2/0-1
DIVLU
SHR
JMPR
Rw
Rw, #data4
cc_NN, rel
5E
5F
2/1
2/1
BCLR
BSET
bitoff.5
bitoff.5
7E
7F
2/1
2/1
BCLR
BSET
bitoff.7
bitoff.7
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C166S V2
Instruction Set
Hexcode
80
81
82
83
84
Bytes/
Cycles
2/1
2/1
4/1
4/co
4/2
Mnemonic
Operands
Hexcode
A0
A1
A2
A3
A4
Bytes/
Cycles
2/1
2/1
4/1
4/co
4/2
Mnemonic
Operands
CMPI1
NEG
CMPI1
CoXXX
MOV
Rw, #data4
Rw
Rw, mem
xx
[Rw], mem
CMPD1
NEGB
CMPD1
CoXXX
MOVB
Rw, #data4
Rb
Rw, mem
xx
[Rw], mem
85
86
87
88
4/1
4/1
4/5
2/1
ENWDT
CMPI1
IDLE
MOV
[-Rw], Rw
A5
A6
A7
A8
4/1
4/1
4/1
2/1
DISWDT
CMPD1
SRVWDT
MOV
89
2/1
MOVB
[-Rw], Rb
A9
2/1
MOVB
Rb, [Rw]
8A
4/1
JB
bitaddr, rel
AA
4/1
JBC
bitaddr, rel
8B
8C
8D
-/2/1
2/0-1
SBRK
JMPR
-
2/2
2/1
2/0-1
CALLI
ASHR
JMPR
cc, [Rw]
Rw, Rw
cc_SGT, rel
8E
8F
90
91
2/1
2/1
2/1
2/1
BCLR
BSET
CMPI2
CPL
cc_C, rel or
cc_ULT, rel
bitoff.8
bitoff.8
Rw, #data4
Rw
AB
AC
AD
AE
AF
B0
B1
2/1
2/1
2/1
2/1
BCLR
BSET
CMPD2
CPLB
bitoff.10
bitoff.10
Rw, #data4
Rb
92
93
94
4/1
4/co
4/2
CMPI2
CoXXX
MOV
Rw, mem
xxx
mem, [Rw]
B2
B3
B4
4/1
4/1
4/2
CMPD2
CoSTORE
MOVB
Rw, mem
[Rw*], CoREG
mem, [Rw]
95
96
97
-/4/1
4/5
CMPI2
PWRDN
Rw, #data16
B5
B6
B7
4/1
4/1
4/5
EINIT
CMPD2
SRST
Rw, #data16
98
99
9A
2/1
2/1
4/1
MOV
MOVB
JNB
Rw, [Rw+]
Rb, [Rw+]
bitaddr, rel
B8
B9
BA
2/1
2/1
4/1
MOV
MOVB
JNBS
[Rw], Rw
[Rw], Rb
bitaddr, rel
9B
9C
2/2-3
2/1
TRAP
JMPI
#trap7
cc, [Rw]
BB
BC
2/1
2/1
CALLR
ASHR
rel
Rw, #data4
9D
2/0-1
JMPR
BD
2/0-1
JMPR
cc_SLE, rel
9E
9F
2/1
2/1
BCLR
BSET
cc_NC, rel or
cc_UGE, rel
bitoff.9
bitoff.9
BE
BF
2/1
2/1
BCLR
BSET
bitoff.11
bitoff.11
User Manual
Rw, #data16
7-197
Rw, #data16
Rw, [Rw]
V 1.7, 2001-01
User Manual
C166S V2
Instruction Set
Hexcode
C0
C1
C2
C3
C4
Bytes/
Cycles
2/1
-/1
4/1
4/1
4/1
Mnemonic
Operands
Hexcode
E0
E1
E2
E3
E4
Bytes/
Cycles
2/1
2/1
4/2
-/4/1
Mnemonic
Operands
MOVBZ
MOVBZ
CoSTORE
MOV
C5
C6
C7
C8
4/1
4/2
-/2/2
MOVBZ
SCXT
MOV
Rw, Rb
reg, mem
Rw, CoREG
[Rw+#data16],
Rw
mem, reg
reg, #data16
[Rw], [Rw]
MOV
MOVB
PCALL
MOVB
E5
E6
E7
E8
-/4/1
4/1
2/2
MOV
MOVB
MOV
Rw, #data4
Rb, #data4
reg, caddr
[Rw+#data16],
Rb
reg, #data16
reg, #data8
[Rw], [Rw+]
C9
2/2
MOVB
[Rw], [Rw]
E9
2/2
MOVB
[Rw], [Rw+]
CA
4/1
CALLA
cc, addr
EA
4/0-1
JMPA
cc, caddr
CB
CC
CD
2/1
2/1-31
2/0-1
RET
NOP
JMPR
cc_SLT, rel
EB
EC
ED
2/2
2/1
2/0-1
RETP
PUSH
JMPR
reg
reg
cc_UGT, rel
CE
CF
D0
D1
2/1
2/1
2/1
2/1
D2
D3
D4
4/1
4/2
4/1
BCLR
BSET
MOVBS
ATOMIC or
EXTR
MOVBS
CoMOV
MOV
bitoff.12
bitoff.12
Rw, Rb
#irang2
EE
EF
F0
F1
2/1
2/1
2/1
2/1
BCLR
BSET
MOV
MOVB
bitoff.14
bitoff.14
Rw, Rw
Rb, Rb
F2
F3
F4
4/1
4/1
4/1
MOV
MOVB
MOVB
MOVBS
SCXT
EXTP(R),
EXTS(R)
reg, mem
[IDX*], [Rw*]
Rw,
[Rw + #data16]
mem, reg
reg, mem
#pag10,#irang2
#seg8, #irang2
F5
F6
F7
-/4/1
4/1
MOV
MOVB
reg, mem
reg, mem
Rb,
[Rw + #data16]
mem, reg
mem, reg
D5
D6
D7
4/1
4/2
4/1
D8
D9
DA
2/2
2/2
4/2
MOV
MOVB
CALLS
[Rw+], [Rw]
[Rw+], [Rw]
seg, caddr
F8
F9
FA
-/-/4/0-1
JMPS
seg, caddr
DB
DC
2/2
2/1
Rw, #irang2
FB
FC
2/5-6
2/1
RETI
POP
reg
DD
2/0-1
RETS
EXTP(R),
EXTS(R)
JMPR
cc_SGE, rel
FD
2/0-1
JMPR
cc_ULE, rel
DE
DF
2/1
2/1
BCLR
BSET
bitoff.13
bitoff.13
FE
FF
2/1
2/1
BCLR
BSET
bitoff.15
bitoff.15
User Manual
7-198
V 1.7, 2001-01
User Manual
C166S V2
Instruction Set
Hex-code Extended
Hex-code
83
00
83
01
83
02
83
08
83
0A
83
10
83
11
83
12
83
20
83
22
83
2A
83
30
83
31
83
3A
83
40
83
41
83
42
83
48
83
4A
83
50
83
51
83
52
83
60
83
62
83
6A
83
70
83
71
83
7A
83
80
83
81
83
88
83
8A
83
90
83
91
83
9A
83
A0
83
AA
83
B0
83
B1
83
BA
83
C0
83
C1
83
C2
83
C8
User Manual
Cycles
Mnemonic
Operands
1
2
1
1
1
1
2
1
1
1
1
1
2
1
1
2
1
1
1
1
2
1
1
1
1
1
2
1
1
2
1
1
1
2
1
1
1
1
2
1
1
2
1
1
CoMULu
CoMULu
CoADD
CoMULuCoSUB
CoMACu
CoMACu
CoSUBR
CoMACuCoLOAD
CoLOADCoMACRu
CoMACRu
CoMAX
CoMULsu
CoMULsu
CoADD2
CoMULsuCoSUB2
CoMACsu
CoMACsu
CoSUB2R
CoMACsuCoLOAD2
CoLOAD2CoMACRsu
CoMACRsu
CoMIN
CoMULus
CoMULus
CoMULusCoSHL
CoMACus
CoMACus
CoSHR
CoMACusCoASHR
CoMACRus
CoMACRus
CoASHR
CoMUL
CoMUL
CoCMP
CoMUL-
RWn, [RWm*]
RWn, [RWm*], rnd
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*], rnd
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*], rnd
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*], rnd
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*], rnd
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*], rnd
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*], rnd
RWn, [RWm*]
[RWm*]
RWn, [RWm*]
RWn, [RWm*], rnd
[RWm*]
RWn, [RWm*]
[RWm*]
RWn, [RWm*]
RWn, [RWm*], rnd
[RWm*] , rnd
RWn, [RWm*]
RWn, [RWm*], rnd
RWn, [RWm*]
RWn, [RWm*]
7-199
V 1.7, 2001-01
User Manual
C166S V2
Instruction Set
Hex-code Extended
Hex-code
83
CA
83
D0
83
D1
83
E0
83
F0
83
F1
93
00
93
01
93
02
93
08
93
0A
93
10
93
11
93
12
93
18
93
19
93
20
93
22
93
28
93
2A
93
30
93
31
93
38
93
39
93
3A
93
40
93
41
93
42
93
48
93
4A
93
50
93
51
93
52
93
58
93
59
93
5A
93
5A
93
5A
93
60
93
62
93
68
93
6A
93
70
93
71
93
78
User Manual
Cycles
Mnemonic
Operands
1
1
2
1
1
2
1
2
1
1
1
1
2
1
1
2
1
1
1
1
1
2
1
2
1
1
2
1
1
1
1
2
1
1
2
1
1
1
1
1
1
1
1
2
1
CoABS
CoMAC
CoMAC
CoMACCoMACR
CoMACR
CoMULu
CoMULu
CoADD
CoMULuCoSUB
CoMACu
CoMACu
CoSUBR
CoMACMu
CoMACMu
CoMACuCoLOAD
CoMACMuCoLOADCoMACRu
CoMACRu
CoMACMRu
CoMACMRu
CoMAX
CoMULsu
CoMULsu
CoADD2
CoMULsuCoSUB2
CoMACsu
CoMACsu
CoSUB2R
CoMACMsu
CoMACMsu
CoNOP
CoNOP
CoNOP
CoMACsuCoLOAD2
CoMACMsuCoLOAD2CoMACRsu
CoMACRsu
CoMACMRsu
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*], rnd
RWn, [RWm*]
RWn, [RWm*]
RWn, [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*]
[IDXi*], [RWm*]
[RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
7-200
V 1.7, 2001-01
User Manual
C166S V2
Instruction Set
Hex-code Extended
Hex-code
93
79
93
7A
93
80
93
81
93
88
93
90
93
91
93
98
93
99
93
A0
93
A8
93
B0
93
B1
93
B8
93
B9
93
C0
93
C1
93
C2
93
C8
93
CA
93
D0
93
D1
93
D8
93
D9
93
E0
93
E8
93
F0
93
F1
93
F8
93
F9
A3
00
A3
01
A3
02
A3
08
A3
0A
A3
10
A3
11
A3
12
A3
1A
A3
20
A3
22
A3
2A
A3
30
A3
31
A3
32
User Manual
Cycles
Mnemonic
Operands
2
1
1
2
1
1
2
1
2
1
1
1
2
1
2
1
2
1
1
1
1
2
1
2
1
1
1
2
1
2
1
2
1
1
1
1
2
1
1
1
1
1
1
2
1
CoMACMRsu
CoMIN
CoMULus
CoMULus
CoMULusCoMACus
CoMACus
CoMACMus
CoMACMus
CoMACusCoMACMusCoMACRus
CoMACRus
CoMACMRus
CoMACMRus
CoMUL
CoMUL
CoCMP
CoMULCoABS
CoMAC
CoMAC
CoMACM
CoMACM
CoMACCoMACMCoMACR
CoMACR
CoMACMR
CoMACMR
CoMULu
CoMULu
CoADD
CoMULuCoSUB
CoMACu
CoMACu
CoSUBR
CoABS
CoMACuCoLOAD
CoLOADCoMACRu
CoMACRu
CoNEG
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*] , rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*]
[IDXi*], [RWm*], rnd
[IDXi*], [RWm*]
[IDXi*], [RWm*] , rnd
RWn, RWm
RWn, RWm, rnd
RWn, RWm
RWn, RWm
RWn, RWm
RWn, RWm
RWn, RWm, rnd
RWn, RWm
7-201
RWn, RWm
RWn, RWm
RWn, RWm
RWn, RWm
RWn, RWm , rnd
V 1.7, 2001-01
User Manual
C166S V2
Instruction Set
Hex-code Extended
Hex-code
A3
3A
A3
40
A3
41
A3
42
A3
48
A3
4A
A3
50
A3
51
A3
52
A3
60
A3
62
A3
6A
A3
70
A3
71
A3
72
A3
7A
A3
80
A3
81
A3
82
A3
88
A3
8A
A3
90
A3
91
A3
92
A3
9A
A3
A0
A3
A2
A3
AA
A3
B0
A3
B1
A3
B2
A3
B2
A3
BA
A3
C0
A3
C1
A3
C2
A3
C8
A3
CA
A3
D0
A3
D1
A3
E0
A3
F0
User Manual
Cycles
Mnemonic
Operands
1
1
2
1
1
1
1
2
1
1
1
1
1
2
1
1
1
2
1
1
1
1
2
1
1
1
1
1
1
2
1
1
1
1
2
1
1
1
1
2
1
1
CoMAX
CoMULsu
CoMULsu
CoADD2
CoMULsuCoSUB2
CoMACsu
CoMACsu
CoSUB2R
CoMACsuCoLOAD2
CoLOAD2CoMACRsu
CoMACRsu
CoNEG
CoMIN
CoMULus
CoMULus
CoSHL
CoMULusCoSHL
CoMACus
CoMACus
CoSHR
CoSHR
CoMACusCoASHR
CoASHR
CoMACRus
CoMACRus
CoASHR
CoRND
CoASHR
CoMUL
CoMUL
CoCMP
CoMULCoABS
CoMAC
CoMAC
CoMACCoMACR
RWn, RWm
RWn, RWm
RWn, RWm , rnd
RWn, RWm
RWn, RWm
RWn, RWm
RWn, RWm
RWn, RWm , rnd
RWn, RWm
RWn, RWm
RWn, RWm
RWn, RWm
RWn, RWm
RWn, RWm , rnd
rnd
RWn, RWm
RWn, RWm
RWn, RWm, rnd
#data5
RWn, RWm
RWn
RWn, RWm
RWn, RWm, rnd
#data5
RWn
RWn, RWm
#data5
RWn
RWn, RWm
RWn, RWm, rnd
#data5, rnd
7-202
RWn, rnd
RWn, RWm
RWn, RWm, rnd
RWn, RWm
RWn, RWm
RWn, RWm
RWn, RWm
RWn, RWm, rnd
RWn, RWm
RWn, RWm
V 1.7, 2001-01
User Manual
C166S V2
Instruction Set
Hex-code Extended
Hex-code
A3
F1
B3
C3
D3
00
User Manual
Cycles
Mnemonic
Operands
2
1
1
2
CoMACR
CoSTORE
CoSTORE
CoMOV
RWn, RWm, rnd
[RWn*], CoReg
RWn, CoReg
[IDXi*], [RWm*]
7-203
V 1.7, 2001-01
User Manual
C166S V2
Instruction Set
User Manual
7-204
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
8
Detailed Instruction Description
This section describes each instruction in detail. The instructions are listed
alphabetically, and the description contains the following elements.
• Instruction Name: Specifies the mnemonic opcode of the instruction in oversized
bold lettering for easy reference. The mnemonics have been chosen with regard to the
particular operation performed by the instruction.
• Syntax: Specifies the mnemonic opcode and the required formal operands of the
instruction as used in the following subsection 'Operation'. There are instructions with
either none, one, two or three operands, which must be separated from each other by
commas:
MNEMONIC
{op1 {,op2 {,op3 } } }
The syntax for the actual operands of an instruction depends on the selected addressing
mode. All of the available addressing modes are summarized at the end of each single
instruction description. In contrast to the syntax for the instructions described in the
following material, the assembler provides much more flexibility in writing C166S V2
CPU programs (e.g. by generic instructions and by automatically selecting appropriate
addressing modes whenever possible). Thus, it eases the use of the instruction set.
• Operation: This part presents a logical description of the operation performed by an
instruction as a symbolic formula or a high level language construct.
The following symbols are used to represent data movement, arithmetic, or logical
operators.
Diadic operations: (opX)
operator (opY)
¨
(opY)
is
MOVED into (opX)
+
(opX)
is
ADDED to (opY)
-
(opY)
is
SUBTRACTED from (opX)
*
(opX)
is
MULTIPLIED by (opY)
/
(opX)
is
DIVIDED by (opY)
Ÿ
(opX)
is
logically ANDed with (opY)
⁄
(opX)
is
logically ORed with (opY)
Ý
(opX)
is
logically EXCLUSIVELY ORed with (opY)
¤
(opX)
is
COMPARED against (opY)
mod
(opX)
is
divided MODULO (opY)
||
(opX)
is
CONCATENATED (opY)
Monadic operations:
operator (opX)
User Manual
8-205
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
ÿ
(opX)
is
logically COMPLEMENTED
Parentheses indicate a method of addressing the used operand as follows:
opX
Specifies the immediate constant value of opX
(opX)
Specifies the contents of opX
(opX[n])
Specifies the contents of bit n of opX
((opX))
Specifies the contents of the contents of opX
(ie. opX is used as pointer to the actual operand)
The following operands notation will also be used in the operational description:
User Manual
CP
Context Pointer
CSP
Code Segment Pointer
IP
Instruction Pointer
MD
Multiply/Divide register
(32 bits wide, consists of MDH and MDL)
MDL, MDH
Multiply/Divide Low and High registers
(each 16 bit wide)
ACC
Accumulator
(40 bits wide, consists of MAE, MAH and MDL)
MAH, MAL
Accumulator Low and High registers
(each 16 bits wide)
MAE
Accumulator extension register (one byte wide)
PSW
Program Status Word
SP
System Stack Pointer
CPUCON1
CPU Configuration register
C
Carry condition flag in the PSW register
V
Overflow condition flag in the PSW register
SGTDIS
Segmentation Disable bit in the SYSCON register
count
Temporary variable for an intermediate storage of
the number of shift or rotate cycles which remain
to complete the shift or rotate operation
tmp
Temporary variable for an intermediate result
0, 1, 2,...
Constant values due to the data format
of the specified operation
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Data Types: This part specifies the particular data type according to the instruction.
Basically, the following data types are possible:
BIT, BYTE, WORD, DOUBLEWORD, ACC = 40-bit signed value
Only CoXXX instructions and instructions which extend byte data to word data can
change the data type. Note that the data types mentioned in this subsection do not cover
accesses to indirect address pointers or to the system stack. These accesses are always
performed with word data. Moreover, no data type is specified for System Control
Instructions and for those branch instructions which do not access any explicitly
addressed data.
• Description: This part provides a brief description of the action that is executed by
the respective instruction.
• Condition Code: The Condition code indicates that the respective instruction is
executed if the specified condition exists, and is skipped if it does not. The table below
summarizes the sixteen possible condition codes that can be used within Call and
Branch instructions. The table shows the abbreviations, the test that is executed for a
specific condition, and a 4/5-bit number associated with condition code.
Condition
Code
Mnemonic
cc
Test
Description
Condition
Code
Number
c
Condition
Code
Number
d
cc_UC
1=1
Unconditional
0H
0H
cc_Z
Z=1
Zero
2H
4H
cc_NZ
Z=0
Not zero
3H
6H
cc_V
V=1
Overflow
4H
8H
cc_NV
V=0
No overflow
5H
AH
cc_N
N=1
Negative
6H
CH
cc_NN
N=0
Not negative
7H
EH
cc_C
C=1
Carry
8H
10H
cc_NC
C=0
No carry
9H
12H
cc_EQ
Z=1
Equal
2H
4H
cc_NE
Z=0
Not equal
3H
6H
cc_ULT
C=1
Unsigned less than
8H
10H
cc_ULE
(Z∨C) = 1
Unsigned less than or equal
FH
1EH
cc_UGE
C=0
Unsigned greater than or equal 9H
12H
cc_UGT
(Z∨C) = 0
Unsigned greater than
1CH
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Condition
Code
Mnemonic
cc
Test
Description
Condition
Code
Number
c
Condition
Code
Number
d
cc_SLT
(N⊕V) = 1
Signed less than
CH
18H
cc_SLE
(Z∨(N⊕V)) = 1 Signed less than or equal
BH
16H
cc_SGE
(N⊕V) = 0
DH
1AH
cc_SGT
(Z∨(N⊕V)) = 0 Signed greater than
AH
14H
cc_NET
(Z∨E) = 0
Not equal AND not end of table 1H
02H
cc_nusr01)
usr0 = 0
usr0 is cleared
1H
cc_nusr11)
usr1 = 0
usr1 is cleared
3H
cc_usr01)
usr0 = 1
usr0 is set
5H
cc_usr11)
usr1 = 1
usr1 is set
7H
1)
Signed greater than or equal
Only usable with the JMA and CALLA instructions.
• Condition Flags: This part reflects the state of the N, C, V, Z, and E flags in the PSW
register which is the state after execution of the corresponding instruction, except if
the PSW register itself was specified as the destination operand of that instruction
(see Note).
The resulting state of the flags is represented by symbols as follows:
'*'
The flag is set due to the following standard rules for the corresponding flag:
N=1:
MSB of the result is set
N=0:
MSB of the result is not set
C=1:
Carry occurred during operation
C=0:
No Carry occurred during operation
V=1:
Arithmetic Overflow occurred during operation
V=0:
No Arithmetic Overflow occurred during operation
Z=1:
Result equals zero
Z=0:
Result does not equal zero
E=1:
Source operand represents the lowest negative number
(either 8000h for word data or 80h for byte data)
E=0:
Source operand does not represent the lowest negative
number for the specified data type
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’S’
The flag is set due to rules which deviate from the described standard.
For more details see instruction pages (below) or the ALU status flags
description.
’-’
The flag is not affected by the operation.
’0’
The flag is cleared by the operation.
’NOR’
The flag contains the logical NORing of the two specified bit operands.
’AND’
The flag contains the logical ANDing of the two specified bit operands.
’OR’
The flag contains the logical ORing of the two specified bit operands.
’XOR’
The flag contains the logical XORing of the two specified bit operands.
’B’
The flag contains the original value of the specified bit operand.
’B’
The flag contains the complemented value of the specified bit operand.
Note: If the PSW register was specified as the destination operand of an instruction, the
condition flags can not be interpreted as just described, because the PSW register
is modified depending on the data format of the instruction as follows:
For word operations, the PSW register is overwritten with the word result. For byte
operations, the non-addressed byte is cleared and the addressed byte is
overwritten. For bit or bit-field operations on the PSW register, only the specified
bits are modified. Supposed that the condition flags were not selected as
destination bits, they stay unchanged. This means that they keep the state after
execution of the previous instruction.
In any case, if the PSW was the destination operand of an instruction, the PSW
flags do NOT represent the condition flags of this instruction as usual.
• Addressing Modes: This part specifies which combinations of different addressing
modes are available for the required operands. The selected addressing mode
combination is usually specified by the opcode of the corresponding instruction.
However, there are some arithmetic and logical instructions for which the addressing
mode combination is not specified by the (identical) opcodes but by particular bits
within the operand field.
The addressing mode entries are made up of three elements:
Mnemonic Shows accepted operands for the respective instruction.
Format This part specifies the format of the instructions as it is represented in the
assembler listing. Figure 8-1 shows the relation between the instruction format
representation of the assembler and the corresponding internal organization of such an
instruction format (N = nibble = 4 bits).
The following symbols are used to describe the instruction formats:
00H through FFH: Instruction Opcodes
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0, 1
: Constant Values
:....
: Each of the 4 characters immediately following a colon represents a single bit
:..ii
: 2-bit short GPR address (Rwi)
SS
: Code segment number
:..##
: 2-bit immediate constant (#irang2)
:.###
: 3-bit immediate constant (#data3)
...#:#
: 5-bit immediate constant (#data5)
c
: 4-bit condition code specification (cc)
d
: 5-bit condition code specification (xcc)
n
: 4-bit short GPR address (Rwn or Rbn)
m
: 4-bit short GPR address (Rwm or Rbm)
q
: 4-bit position of the source bit within the word specified by QQ
qqq
: 3-bit addressing mode specifier for CoXXX instructions
z
: 4-bit position of the destination bit within the word specified by ZZ
#
: 4-bit immediate constant (#data4)
t:ttt0
: 7-bit trap number (#trap7)
QQ
: 8-bit word address of the source bit (bitoff)
rr
: 8-bit relative target address word offset (rel)
rrr
: 3-bit repeat control for CoXXX instructions
RR
: 8-bit word address reg
wwww:w : 5-bit word address CoREG
X
: 4-bit addressing mode specifier for CoXXX instructions
ZZ
: 8-bit word address of the destination bit (bitoff)
##
: 8-bit immediate constant (#data8)
## xx
: 8-bit immediate constant (represented by #data16, byte xx is not significant)
@@
: 8-bit immediate constant (#mask8)
MM MM : 16-bit address (mem or caddr; low byte, high byte)
## ##
: 16-bit immediate constant (#data16; low byte, high byte)
a
: 1-bit branch assumption bit
l
: 1-bit short backward loop bit
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Number of Bytes All C166S V2 CPU instructions are either 2 or 4 bytes. According to
the instruction size, all instructions can be classified as either single word or double word
instructions.
Representation in the
Assembler Listing:
N2N1
N4N3
N6N5
N8N7
High Byte 2nd word
Low Byte 2nd word
High Byte 1st word
Low Byte 1st word
Internal Organization:
MSB
N8
Figure 8-1
Bits in ascending order LSB
N7
N6
N5
N4
N3
N2
N1
Instruction Format Representation
The following pages contain a detailed description of each normal arithmetic, logic,
branch or system instruction in alphabetical order followed by a list of the dedicated DSP
instructions:
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8.1
Normal Instruction Set
ADD
ADD
Integer Addition
Group
Arithmetic Instructions
Syntax
ADD op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
op1 → WORD
Operation
(op1) ← (op1) + (op2)
Description
Performs a 2s complement binary addition of the source operand specified by op2 and
the destination operand specified by op1. The result is then stored in op1.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
*
C
*
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the word data type. Cleared otherwise.
Set if a carry is generated from the most significant bit of the word data
type. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
ADD
ADD
ADD
ADD
ADD
ADD
ADD
User Manual
Rwn , #data3
Rwn , Rwm
Rwn , [Rwi+]
Rwn , [Rwi]
mem , reg
reg , #data16
reg , mem
Format
08 n:0###
00 nm
08 n:11ii
08 n:10ii
04 RR MM MM
06 RR ## ##
02 RR MM MM
8-212
Bytes
2
2
2
2
4
4
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ADDB
ADDB
Integer Addition
Group
Arithmetic Instructions
Syntax
ADDB op1, op2
Source Operand(s)
op1, op2 → BYTE
Destination Operand(s)
op1 → BYTE
Operation
(op1) ← (op1) + (op2)
Description
Performs a 2s complement binary addition of the source operand specified by op2 and
the destination operand specified by op1. The result is then stored in op1.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
*
C
*
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the byte data type. Cleared otherwise.
Set if a carry is generated from the most significant bit of the byte data
type. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
ADDB
ADDB
ADDB
ADDB
ADDB
ADDB
ADDB
User Manual
Rbn , #data3
Rbn , Rbm
Rbn , [Rwi+]
Rbn , [Rwi]
mem , reg
reg , #data8
reg , mem
Format
09 n:0###
01 nm
09 n:11ii
09 n:10ii
05 RR MM MM
07 RR ## xx
03 RR MM MM
8-213
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2
2
2
2
4
4
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ADDC
ADDC
Integer Addition with Carry
Group
Arithmetic Instructions
Syntax
ADDC op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
op1 → WORD
Operation
(op1) ← (op1) + (op2) + (C)
Description
Performs a 2s complement binary addition of the source operand specified by op2, the
destination operand specified by op1 and the previously generated carry bit. The sum is
then stored in op1. This instruction can be used to perform multiple precision arithmetic.
CPU Flags
E
*
E
Z
V
C
N
Z
S
V
*
C
*
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero and previous Z flag was set. Cleared otherwise.
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the word data type. Cleared otherwise.
Set if a carry is generated from the most significant bit of the word data
type. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
ADDC
ADDC
ADDC
ADDC
ADDC
ADDC
ADDC
User Manual
Rwn , #data3
Rwn , Rwm
Rwn , [Rwi+]
Rwn , [Rwi]
mem , reg
reg , #data16
reg , mem
Format
18 n:0###
10 nm
18 n:11ii
18 n:10ii
14 RR MM MM
16 RR ## ##
12 RR MM MM
8-214
Bytes
2
2
2
2
4
4
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ADDCB
ADDCB
Integer Addition with Carry
Group
Arithmetic Instructions
Syntax
ADDCB op1, op2
Source Operand(s)
op1, op2 → BYTE
Destination Operand(s)
op1 → BYTE
Operation
(op1) ← (op1) + (op2) + (C)
Description
Performs a 2s complement binary addition of the source operand specified by op2, the
destination operand specified by op1 and the previously generated carry bit. The sum is
then stored in op1. This instruction can be used to perform multiple precision arithmetic.
CPU Flags
E
*
E
Z
V
C
N
Z
S
V
*
C
*
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero and previous Z flag was set. Cleared otherwise.
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the byte data type. Cleared otherwise.
Set if a carry is generated from the most significant bit of the byte data
type. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
ADDCB
ADDCB
ADDCB
ADDCB
ADDCB
ADDCB
ADDCB
User Manual
Rbn , #data3
Rbn , Rbm
Rbn , [Rwi+]
Rbn , [Rwi]
mem , reg
reg , #data8
reg , mem
Format
19 n:0###
11 nm
19 n:11ii
19 n:10ii
15 RR MM MM
17 RR ## xx
13 RR MM MM
8-215
Bytes
2
2
2
2
4
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Detailed Instruction Description
AND
AND
Logical AND
Group
Logical Instructions
Syntax
AND op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
op1 → WORD
Operation
(op1) ← (op1) ∧ (op2)
Description
Performs a bitwise logical AND of the source operand specified by op2 and the
destination operand specified by op1. The result is then stored in op1.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
0
C
0
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Always cleared.
Always cleared.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
AND
AND
AND
AND
AND
AND
AND
User Manual
Rwn , #data3
Rwn , Rwm
Rwn , [Rwi+]
Rwn , [Rwi]
mem , reg
reg , #data16
reg , mem
Format
68 n:0###
60 nm
68 n:11ii
68 n:10ii
64 RR MM MM
66 RR ## ##
62 RR MM MM
8-216
Bytes
2
2
2
2
4
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Detailed Instruction Description
ANDB
ANDB
Logical AND
Group
Logical Instructions
Syntax
ANDB op1, op2
Source Operand(s)
op1, op2 → BYTE
Destination Operand(s)
op1 → BYTE
Operation
(op1) ← (op1) ∧ (op2)
Description
Performs a bitwise logical AND of the source operand specified by op2 and the
destination operand specified by op1. The result is then stored in op1.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
0
C
0
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Always cleared.
Always cleared.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
ANDB
ANDB
ANDB
ANDB
ANDB
ANDB
ANDB
User Manual
Rbn , #data3
Rbn , Rbm
Rbn , [Rwi+]
Rbn , [Rwi]
mem , reg
reg , #data8
reg , mem
Format
69 n:0###
61 nm
69 n:11ii
69 n:10ii
65 RR MM MM
67 RR ## xx
63 RR MM MM
8-217
Bytes
2
2
2
2
4
4
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Detailed Instruction Description
ASHR
ASHR
Arithmetic Shift Right
Group
Shift and Rotate Instructions
Syntax
ASHR op1, op2
Source Operand(s)
op1 → WORD
op2 → shift counter
Destination Operand(s)
op1 → WORD
Operation
(count) ← (op2)
(V) ← 0
(C) ← 0
DO WHILE ((count) ≠ 0)
(V) ← (C) ∨ (V)
(C) ← (op1[0])
(op1[n]) ← (op1[n+1]) [n=0...14]
(count) ← (count) - 1
END WHILE
Description
Arithmetically shifts the destination word operand op1 right by the number of times as
specified by the source operand op2. To preserve the sign of the original operand op1,
the most significant bits of the result are filled with zeros if the original most significant
bit was a 0 or with ones if the original most significant bit was a 1. The Overflow flag is
used as a Rounding flag. The least significant bit is shifted into the Carry. Only shift
values between 0 and 15 are allowed. When using a GPR as the count control, only the
least significant 4 bits are used.
CPU Flags
E
0
E
Z
V
C
N
User Manual
Z
*
V
*
C
*
N
*
Always cleared.
Set if result equals zero. Cleared otherwise.
Set if in any cycle of the shift operation a 1 is shifted out of the carry flag.
Cleared in case of a shift count equal 0.
The carry flag is set according to the last least significant bit shifted out of
op1. Cleared for a shift count of zero.
Set if the most significant bit of the result is set. Cleared otherwise.
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Encoding
Mnemonic
ASHR
ASHR
User Manual
Rwn , #data4
Rwn , Rwm
Format
BC #n
AC nm
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Bytes
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Detailed Instruction Description
ATOMIC
ATOMIC
Begin ATOMIC Sequence
Group
System Control Instructions
Syntax
ATOMIC op1
Source Operand(s)
op1 → 2-bit instruction counter
Destination Operand(s)
none
Operation
(count) ← (op1) [1 ≤ op1 ≤ 4]
Disable interrupts and Class A traps
DO WHILE ((count) ≠ 0 AND Class_B_Trap_Condition ≠ TRUE)
Next Instruction
(count) ← (count) - 1
END WHILE
(count) ← 0
Enable interrupts and traps
Description
Causes standard and PEC interrupts and class A hardware traps to be disabled for a
specified number of instructions. The ATOMIC instruction becomes immediately active.
No NOPs are required for normal ATOMIC execution. Depending on the value of op1,
the period of validity of the ATOMIC sequence extends over the sequence of the next
one to four instructions being executed after the ATOMIC instruction. All instructions
requiring multiple cycles or hold states to be executed are regarded as one instruction
in this sense. Any instruction type can be used with the ATOMIC instruction.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
ATOMIC
User Manual
#irang2
Format
D1 :00##-0
8-220
Bytes
2
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Detailed Instruction Description
BAND
BAND
Bit Logical AND
Group
Boolean Bit Manipulation Instructions
Syntax
BAND op1, op2
Source Operand(s)
op1, op2 → BIT
Destination Operand(s)
op1 → BIT
Operation
(op1) ← (op1) ∧ (op2)
Description
Performs a single bit logical AND of the source bit specified by op2 and the destination
bit specified by op1. The result is then stored in op1.
CPU Flags
E
0
E
Z
V
C
N
Z
NOR
V
OR
C
AND
N
XOR
Always cleared.
Contains the logical NOR of the two specified bits.
Contains the logical OR of the two specified bits.
Contains the logical AND of the two specified bits.
Contains the logical XOR of the two specified bits.
Encoding
Mnemonic
BAND
User Manual
bitaddrZ.z , bitaddrQ.q
Format
6A QQ ZZ qz
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Detailed Instruction Description
BCLR
BCLR
Bit Clear
Group
Boolean Bit Manipulation Instructions
Syntax
BCLR op1
Source Operand(s)
none
Destination Operand(s)
op1 → BIT
Operation
(op1) ← 0
Description
Clears the bit specified by op1. This instruction is primarily used for peripheral and
system control.
CPU Flags
E
0
E
Z
V
C
N
Z
B
V
0
C
0
N
B
Always cleared.
Contains the logical negation of the previous state of the specified bit.
Always cleared.
Always cleared.
Contains the previous state of the specified bit.
Encoding
Mnemonic
BCLR
User Manual
bitaddrQ.q
Format
qE QQ
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Detailed Instruction Description
BCMP
BCMP
Bit to Bit Compare
Group
Boolean Bit Manipulation Instructions
Syntax
BCMP op1, op2
Source Operand(s)
op1, op2 → BIT
Destination Operand(s)
none
Operation
(op1) ⇔ (op2)
Description
Performs a single bit comparison of the source bit specified by op1 and the source bit
specified by op2. No result is written by this instruction. Only the flags are updated.
CPU Flags
E
0
E
Z
V
C
N
Z
NOR
V
OR
C
AND
N
XOR
Always cleared.
Contains the logical NOR of the two specified bits.
Contains the logical OR of the two specified bits.
Contains the logical AND of the two specified bits.
Contains the logical XOR of the two specified bits.
Encoding
Mnemonic
BCMP
User Manual
bitaddrZ.z , bitaddrQ.q
Format
2A QQ ZZ qz
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Detailed Instruction Description
BFLDH
BFLDH
Bit Field High Byte
Group
Boolean Bit Manipulation Instructions
Syntax
BFLDH op1, op2, op3
Source Operand(s)
op1 → WORD
op2, op3 → BYTE
Destination Operand(s)
op1 → WORD
Operation
(count) ← 0
DO WHILE ((count) <8)
IF (op2[(count)] = 1)
(op1[(count) + 8]) ← op3[(count)]
ENDIF
(count) ← (count) + 1
END WHILE
Description
Replaces those bits in the high byte of the destination word operand op1 which are
selected by an ’1’ in the mask specified by op2 with the bits at the corresponding
positions in "op3".
CPU Flags
E
0
E
Z
V
C
N
Z
*
V
0
C
0
N
*
Always cleared.
Set if result equals zero. Cleared otherwise.
Always cleared.
Always cleared.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
BFLDH
User Manual
Format
bitoffQ , #mask8 , #data8 1A QQ ## @@
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Detailed Instruction Description
BFLDL
BFLDL
Bit Field Low Byte
Group
Boolean Bit Manipulation Instructions
Syntax
BFLDL op1, op2, op3
Source Operand(s)
op1 → WORD
op2, op3 → BYTE
Destination Operand(s)
op1 → WORD
Operation
(count) ← 0
DO WHILE ((count) <8)
IF op2[(count)] = 1
(op1[(count)]) ← op3[(count)]
ENDIF
(count) ← (count) + 1
END WHILE
Description
Replaces those bits in the low byte of the destination word operand op1 which are
selected by an ’1’ in the mask specified by op2 with the bits at the corresponding
positions in "op3".
CPU Flags
E
0
E
Z
V
C
N
Z
*
V
0
C
0
N
*
Always cleared.
Set if result equals zero. Cleared otherwise.
Always cleared.
Always cleared.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
BFLDL
User Manual
bitoffQ , #mask8 , #data8
Format
0A QQ @@ ##
8-225
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
BMOV
BMOV
Bit to Bit Move
Group
Boolean Bit Manipulation Instructions
Syntax
BMOV op1, op2
Source Operand(s)
op2 → BIT
Destination Operand(s)
op1 → BIT
Operation
(op1) ← (op2)
Description
Moves a single bit from the source operand specified by op2 into the destination
operand specified by op1. The source bit is examined and the flags are updated
accordingly.
CPU Flags
E
0
E
Z
V
C
N
Z
B
V
0
C
0
N
B
Always cleared.
Contains the logical negation of the source bit.
Always cleared.
Always cleared.
Contains the state of the source bit.
Encoding
Mnemonic
BMOV
User Manual
bitaddrZ.z , bitaddrQ.q
Format
4A QQ ZZ qz
8-226
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
BMOVN
BMOVN
Bit to Bit Move and Negate
Group
Boolean Bit Manipulation Instructions
Syntax
BMOVN op1, op2
Source Operand(s)
op2 → BIT
Destination Operand(s)
op1 → BIT
Operation
(op1) ← ¬(op2)
Description
Moves the complement of a single bit from the source operand specified by op2 into the
destination operand specified by op1. The source bit is examined and the flags are
updated accordingly.
CPU Flags
E
0
E
Z
V
C
N
Z
B
V
0
C
0
N
B
Always cleared.
Contains the logical negation of the source bit.
Always cleared.
Always cleared.
Contains the state of the source bit.
Encoding
Mnemonic
BMOVN
User Manual
bitaddrZ.z , bitaddrQ.q
Format
3A QQ ZZ qz
8-227
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
BOR
BOR
Bit Logical OR
Group
Boolean Bit Manipulation Instructions
Syntax
BOR op1, op2
Source Operand(s)
op1, op2 → BIT
Destination Operand(s)
op1 → BIT
Operation
(op1) ← (op1) ∨ (op2)
Description
Performs a single bit logical OR of the source bit specified by op2 and the destination
bit specified by op1. The result is then stored in op1.
CPU Flags
E
0
E
Z
V
C
N
Z
NOR
V
OR
C
AND
N
XOR
Always cleared.
Contains the logical NOR of the two specified bits.
Contains the logical OR of the two specified bits.
Contains the logical AND of the two specified bits.
Contains the logical XOR of the two specified bits.
Encoding
Mnemonic
BOR
User Manual
bitaddrZ.z , bitaddrQ.q
Format
5A QQ ZZ qz
8-228
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
BSET
BSET
Bit Set
Group
Boolean Bit Manipulation Instructions
Syntax
BSET op1
Source Operand(s)
none
Destination Operand(s)
op1 → BIT
Operation
(op1) ← 1
Description
Sets the bit specified by op1.
CPU Flags
E
0
E
Z
V
C
N
Z
B
V
0
C
0
N
B
Always cleared.
Contains the logical negation of the previous state of the specified bit.
Always cleared.
Always cleared.
Contains the previous state of the specified bit.
Encoding
Mnemonic
BSET
User Manual
bitaddrQ.q
Format
qF QQ
8-229
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
BXOR
BXOR
Bit Logical XOR
Group
Boolean Bit Manipulation Instructions
Syntax
BXOR op1, op2
Source Operand(s)
op1, op2 → BIT
Destination Operand(s)
op1 → BIT
Operation
(op1) ← (op1) ⊕ (op2)
Description
Performs a single bit logical EXCLUSIVE OR of the source bit specified by op2 and the
destination bit specified by op1. The result is then stored in op1.
CPU Flags
E
0
E
Z
V
C
N
Z
NOR
V
OR
C
AND
N
XOR
Always cleared.
Contains the logical NOR of the two specified bits.
Contains the logical OR of the two specified bits.
Contains the logical AND of the two specified bits.
Contains the logical XOR of the two specified bits.
Encoding
Mnemonic
BXOR
User Manual
bitaddrZ.z , bitaddrQ.q
Format
7A QQ ZZ qz
8-230
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CALLA
CALLA
Call Subroutine Absolute
Group
Call Instructions
Syntax
CALLA op1, op2
Alternative Syntax CALLA+ op1, op2
CALLA- op1, op2
Source Operand(s)
op1 → extended condition code
op2 → 16-bit address offset
Destination Operand(s)
none
Operation
IF (op1) THEN
(SP) ← (SP) - 2
((SP)) ← (IP)
(IP) ← op2
ELSE
next instruction
END IF
Description
If the condition specified by op1 is met, a branch to the absolute memory location
specified by the second operand op2 is taken. The value of the instruction pointer IP is
placed into the system stack. Because the IP always points to the instruction following
the branch instruction, the value stored in the system stack represents the return
address of the calling routine. A static prediction scheme is used: if the bit ’a’ of the
instruction long word is cleared then CALLA is assumed ’taken’ and if this bit is set to 1,
CALLA is assumed ’not taken’. CALLA+ and CALLA- instructions are converted into
CALLA assumed ’taken’ (prediction bit cleared) and ’not taken’ (prediction bit set)
respectively. For regular CALLA instructions, the assembler assumes them ’taken’.
CPU Flags
E
E
Z
V
C
User Manual
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
8-231
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
N
Not affected.
Encoding
Mnemonic
CALLA
User Manual
xcc , caddr
Format
CA d00a MM MM
8-232
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CALLI
CALLI
Call Subroutine Indirect
Group
Call Instructions
Syntax
CALLI op1, op2
Source Operand(s)
op1 → condition code
op2 → 16-bit address offset
Destination Operand(s)
none
Operation
IF (op1) THEN
(SP) ← (SP) - 2
((SP)) ← (IP)
(IP) ← op2
ELSE
next instruction
END IF
Description
If the condition specified by op1 is met, a branch to the location specified indirectly by
the second operand op2 is taken. The value of the instruction pointer IP is placed onto
the system stack. Because the IP always points to the instruction following the branch
instruction, the value stored in the system stack represents the return address of the
calling routine. If the condition is not met, no action is taken and the next instruction is
executed normally.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
CALLI
User Manual
cc , [Rwn]
Format
AB cn
8-233
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CALLR
CALLR
Call Subroutine Relative
Group
Call Instructions
Syntax
CALLR op1
Source Operand(s)
op1 → 8-bit signed displacement
Destination Operand(s)
none
Operation
(SP) ← (SP) - 2
((SP)) ← (IP)
(IP) ← (IP) + 2*sign_extend(op1)
Description
A branch is taken to the location specified by the instruction pointer IP plus the relative
displacement op1. The displacement is a two’s complement number which is sign
extended and counts the relative distance in words. The value of the instruction pointer
(IP) is placed into the system stack. Because the IP always points to the instruction
following the branch instruction, the value stored in the system stack represents the
return address of the calling routine. The value of the IP used in the target address
calculation is the address of the instruction following the CALLR instruction.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
CALLR
User Manual
rel
Format
BB rr
8-234
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CALLS
CALLS
Call Inter-Segment Subroutine
Group
Call Instructions
Syntax
CALLS op1, op2
Source Operand(s)
op1 → segment number
op2 → 16-bit address offset
Destination Operand(s)
none
Operation
(SP) ← (SP) - 2
((SP)) ← (CSP)
(SP) ← (SP) - 2
((SP)) ← (IP)
IF (CPUCON1.SGTDIS = 0) THEN
(CSP) ← op1
END IF
(IP) ← op2
Description
A branch is taken to the absolute location specified by op2 within the segment specified
by op1. The previous value of the CSP is placed into the system stack to ensure correct
return to the calling segment. The value of the instruction pointer (IP) is also placed into
the system stack. Because the IP always points to the instruction following the branch
instruction, the value stored on the system stack represents the return address to the
calling routine.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
CALLS
User Manual
seg , caddr
Format
DA SS MM MM
8-235
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CMP
CMP
Integer Compare
Group
Boolean Bit Manipulation Instructions
Syntax
CMP op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
none
Operation
(op1) ⇔ (op2)
Description
The source operand specified by op1 is compared to the source operand specified by
op2 by performing a 2s complement binary subtraction of op2 from op1. The flags are
set according to the rules of subtraction. The operands remain unchanged.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
*
C
S
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the word data type. Cleared otherwise.
Set if a borrow is generated. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CMP
CMP
CMP
CMP
CMP
CMP
User Manual
Rwn , #data3
Rwn , Rwm
Rwn , [Rwi+]
Rwn , [Rwi]
reg , #data16
reg , mem
Format
48 n:0###
40 nm
48 n:11ii
48 n:10ii
46 RR ## ##
42 RR MM MM
8-236
Bytes
2
2
2
2
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CMPB
CMPB
Integer Compare
Group
Boolean Bit Manipulation Instructions
Syntax
CMPB op1, op2
Source Operand(s)
op1, op2 → BYTE
Destination Operand(s)
none
Operation
(op1) ⇔ (op2)
Description
The source operand specified by op1 is compared to the source operand specified by
op2 by performing a 2s complement binary subtraction of op2 from op1. The flags are
set according to the rules of subtraction. The operands remain unchanged.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
*
C
S
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the byte data type. Cleared otherwise.
Set if a borrow is generated. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CMPB
CMPB
CMPB
CMPB
CMPB
CMPB
User Manual
Rbn , #data3
Rbn , Rbm
Rbn , [Rwi+]
Rbn , [Rwi]
reg , #data8
reg , mem
Format
49 n:0###
41 nm
49 n:11ii
49 n:10ii
47 RR ## xx
43 RR MM MM
8-237
Bytes
2
2
2
2
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CMPD1
Integer Compare and Decrement by 1
Group
Compare and Loop Control Instructions
Syntax
CMPD1 op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
op1 → WORD
CMPD1
Operation
(op1) ⇔ (op2)
(op1) ← (op1) - 1
Description
This instruction is used to enhance the performance and flexibility of loops. The source
operand specified by op1 is compared to the source operand specified by op2 by
performing a 2s complement binary subtraction of op2 from op1. Operand op1 may
specify ONLY GPR registers. Once the subtraction has completed, the operand op1 is
decremented by one. Using the set flags, a branch instruction can then be used in
conjunction with this instruction to form common high level language FOR loops of any
range.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
*
C
S
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the word data type. Cleared otherwise.
Set if a borrow is generated. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CMPD1
CMPD1
CMPD1
User Manual
Rwn , #data16
Rwn , #data4
Rwn , mem
Format
A6 Fn ## ##
A0 #n
A2 Fn MM MM
8-238
Bytes
4
2
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CMPD2
Integer Compare and Decrement by 2
Group
Compare and Loop Control Instructions
Syntax
CMPD2 op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
op1 → WORD
CMPD2
Operation
(op1) ⇔ (op2)
(op1) ← (op1) - 2
Description
This instruction is used to enhance the performance and flexibility of loops. The source
operand specified by op1 is compared to the source operand specified by op2 by
performing a 2s complement binary subtraction of op2 from op1. Operand op1 may
specify ONLY GPR registers. Once the subtraction has completed, the operand op1 is
decremented by two. Using the set flags, a branch instruction can then be used in
conjunction with this instruction to form common high level language FOR loops of any
range.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
*
C
S
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the word data type. Cleared otherwise.
Set if a borrow is generated. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CMPD2
CMPD2
CMPD2
User Manual
Rwn , #data16
Rwn , #data4
Rwn , mem
Format
B6 Fn ## ##
B0 #n
B2 Fn MM MM
8-239
Bytes
4
2
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CMPI1
Integer Compare and Increment by 1
Group
Compare and Loop Control Instructions
Syntax
CMPI1 op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
op1 → WORD
CMPI1
Operation
(op1) ⇔ (op2)
(op1) ← (op1) + 1
Description
This instruction is used to enhance the performance and flexibility of loops. The source
operand specified by op1 is compared to the source operand specified by op2 by
performing a 2s complement binary subtraction of op2 from op1. Operand op1 may
specify ONLY GPR registers. Once the subtraction has completed, the operand op1 is
incremented by one. Using the set flags, a branch instruction can then be used in
conjunction with this instruction to form common high level language FOR loops of any
range.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
*
C
S
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the word data type. Cleared otherwise.
Set if a borrow is generated. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CMPI1
CMPI1
CMPI1
User Manual
Rwn , #data16
Rwn , #data4
Rwn , mem
Format
86 Fn ## ##
80 #n
82 Fn MM MM
8-240
Bytes
4
2
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CMPI2
Integer Compare and Increment by 2
Group
Compare and Loop Control Instructions
Syntax
CMPI2 op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
op1 → WORD
CMPI2
Operation
(op1) ⇔ (op2)
(op1) ← (op1) + 2
Description
This instruction is used to enhance the performance and flexibility of loops. The source
operand specified by op1 is compared to the source operand specified by op2 by
performing a 2s complement binary subtraction of op2 from op1. Operand op1 may
specify ONLY GPR registers. Once the subtraction has completed, the operand op1 is
incremented by two. Using the set flags, a branch instruction can then be used in
conjunction with this instruction to form common high level language FOR loops of any
range.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
*
C
S
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the word data type. Cleared otherwise.
Set if a borrow is generated. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CMPI2
CMPI2
CMPI2
User Manual
Rwn , #data16
Rwn , #data4
Rwn , mem
Format
96 Fn ## ##
90 #n
92 Fn MM MM
8-241
Bytes
4
2
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CPL
CPL
Integer One’s Complement
Group
Arithmetic Instructions
Syntax
CPL op1
Source Operand(s)
op1 → WORD
Destination Operand(s)
op1 → WORD
Operation
(op1) ← ¬(op1)
Description
Performs a 1s complement of the source operand specified by op1. The result is stored
back into op1.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
0
C
0
N
*
Set if the value of op1 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Always cleared.
Always cleared.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CPL
User Manual
Rwn
Format
91 n0
8-242
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CPLB
CPLB
Integer One’s Complement
Group
Arithmetic Instructions
Syntax
CPLB op1
Source Operand(s)
op1 → BYTE
Destination Operand(s)
op1 → BYTE
Operation
(op1) ← ¬(op1)
Description
Performs a 1s complement of the source operand specified by op1. The result is stored
back into op1.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
0
C
0
N
*
Set if the value of op1 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Always cleared.
Always cleared.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CPLB
User Manual
Rbn
Format
B1 n0
8-243
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
DISWDT
DISWDT
Disable Watchdog Timer
Group
System Control Instructions
Syntax
DISWDT
Source Operand(s)
none
Destination Operand(s)
none
Operation
Disable the watchdog timer
Description
This instruction disables the Watchdog Timer. If the WDTCTL bit is cleared, the
DISWDT instruction can be executed at any time between the Reset and the first
execution of either EINIT or SRVWDT. After execution of either an EINIT or a
SRVWDT, the DISWDT instruction will have no effect. If the WDTCTL bit is set, the
DISWDT instruction can always be executed regardless of the execution of EINIT or
SRVWDT. To ensure that this instruction is not accidentally executed, it is implemented
as a protected instruction.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
DISWDT
User Manual
Format
A5 5A A5 A5
8-244
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
DIV
DIV
16-by-16 Signed Division
Group
Arithmetic Instructions
Syntax
DIV op1
Source Operand(s)
op1 → WORD
MDL → WORD
Destination Operand(s)
MD → DOUBLEWORD
Operation
(MDL) ← (MDL) / (op1)
(MDH) ← (MDL) mod (op1)
Description
Performs a signed 16-bit by 16-bit division of the low order word stored in the MD
register by the source word operand op1. The signed quotient is then stored in the low
order word of the MD register (MDL) and the remainder is stored in the high order word
of the MD register (MDH).
CPU Flags
E
0
E
Z
V
C
N
Z
*
V
*
C
0
N
*
Always cleared.
Set if quotient, stored in the MDL register, equals zero. Cleared
otherwise. Undefined if the V flag is set.
Set if an arithmetic overflow occurred, i.e. the quotient cannot be
represented in a word data type (only in case of 8000H/FFFEH), or if the
divisor op1 was zero. Cleared otherwise.
Always cleared.
Set if the most significant bit of the quotient, stored in the MDL register, is
set. Cleared otherwise. Undefined if the V flag is set.
Encoding
Mnemonic
DIV
User Manual
Rwn
Format
4B nn
8-245
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
DIVL
DIVL
32-by-16 Signed Division
Group
Arithmetic Instructions
Syntax
DIVL op1
Source Operand(s)
op1 → WORD
MD → DOUBLEWORD
Destination Operand(s)
MD → DOUBLEWORD
Operation
(MDL) ← (MD) / (op1)
(MDH) ← (MD) mod (op1)
Description
Performs an extended signed 32-bit by 16-bit division of the two words stored in the MD
register by the source word operand op1. The signed quotient is then stored in the low
order word of the MD register (MDL) and the remainder is stored in the high order word
of the MD register (MDH).
CPU Flags
E
0
E
Z
V
C
N
Z
*
V
*
C
0
N
*
Always cleared.
Set if quotient, stored in the MDL register, equals zero. Cleared
otherwise. Undefined if the V flag is set.
Set if an arithmetic overflow occurred, i.e. the quotient cannot be
represented in a word data type, or if the divisor op1 was zero. Cleared
otherwise.
Always cleared.
Set if the most significant bit of the quotient, stored in the MDL register, is
set. Cleared otherwise. Undefined if the V flag is set.
Encoding
Mnemonic
DIVL
User Manual
Rwn
Format
6B nn
8-246
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
DIVLU
DIVLU
32-by-16 Unsigned Division
Group
Arithmetic Instructions
Syntax
DIVLU op1
Source Operand(s)
op1 → WORD
MD → DOUBLEWORD
Destination Operand(s)
MD → DOUBLEWORD
Operation
(MDL) ← (MD) / op1
(MDH) ← (MD) mod (op1)
Description
Performs an extended unsigned 32-bit by 16-bit division of the two words stored in the
MD register by the source word operand op1. The unsigned quotient is then stored in
the low order word of the MD register (MDL) and the remainder is stored in the high
order word of the MD register (MDH).
CPU Flags
E
0
E
Z
V
C
N
Z
*
V
*
C
0
N
*
Always cleared.
Set if quotient, stored in the MDL register, equals zero. Cleared
otherwise. Undefined if the V flag is set.
Set if an arithmetic overflow occurred, i.e. the quotient cannot be
represented in a word data type, or if the divisor op1 was zero. Cleared
otherwise.
Always cleared.
Set if the most significant bit of the quotient, stored in the MDL register, is
set. Cleared otherwise. Undefined if the V flag is set.
Encoding
Mnemonic
DIVLU
User Manual
Rwn
Format
7B nn
8-247
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
DIVU
DIVU
16-by-16 Unsigned Division
Group
Arithmetic Instructions
Syntax
DIVU op1
Source Operand(s)
op1 → WORD
MDL → WORD
Destination Operand(s)
MD → DOUBLEWORD
Operation
(MDL) ← (MDL) / (op1)
(MDH) ← (MDL) mod (op1)
Description
Performs an unsigned 16-bit by 16-bit division of the low order word stored in the MD
register by the source word operand op1. The unsigned quotient is then stored in the
low order word of the MD register (MDL) and the remainder is stored in the high order
word of the MD register (MDH).
CPU Flags
E
0
E
Z
V
C
N
Z
*
V
*
C
0
N
*
Always cleared.
Set if quotient, stored in the MDL register, equals zero. Cleared
otherwise. Undefined if the V flag is set.
Set if the divisor op1 was zero.
Always cleared.
Set if the most significant bit of the quotient, stored in the MDL register, is
set. Cleared otherwise. Undefined if the V flag is set.
Encoding
Mnemonic
DIVU
User Manual
Rwn
Format
5B nn
8-248
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
EINIT
EINIT
End of Initialization
Group
System Control Instructions
Syntax
EINIT
Source Operand(s)
none
Destination Operand(s)
none
Operation
End of Initialization
Description
After a reset, the reset output pin RSTOUT is pulled low. It remains low until the EINIT
instruction has been executed at which time it goes high. This enables the software to
signal the external circuitry that it has successfully initialized the microcontroller. After
EINIT execution, registers can be locked until reset. The DISWDT instruction executed
after the first EINIT instruction has effect only if the WDTCTL bit was cleared before the
EINIT instruction. To ensure that this instruction is not accidentally executed, it is
implemented as a protected instruction.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
EINIT
User Manual
Format
B5 4A B5 B5
8-249
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
ENWDT
ENWDT
Enable Watchdog Timer
Group
System Control Instructions
Syntax
ENWDT
Source Operand(s)
none
Destination Operand(s)
none
Operation
Enable Watchdog Timer
Description
If the WDTCTL bit of the CPUCON1 register is cleared, this instruction has no effect. If
the WDTCTL bit is set, this instruction enables the Watchdog Timer. Specifically, it
allows the Watchdog Timer to be re-enabled after it has been previously disabled by a
DISWDT instruction. To ensure that this instruction is not accidentally executed, it is
implemented as a protected instruction.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
ENWDT
User Manual
Format
85 7A 85 85
8-250
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
EXTP
EXTP
Begin EXTended Page Sequence
Group
System Control Instructions
Syntax
EXTP op1, op2
Source Operand(s)
op1 → 10-bit page number
op2 → 2-bit instruction counter
Destination Operand(s)
none
Operation
(count) ← (op2) [1 ≤ op2 ≤ 4]
Disable interrupts and Class A traps
Data_Page ← (op1)
DO WHILE ((count) ≠ 0 AND Class_B_Trap_Condition ≠ TRUE)
Next Instruction
(count) ← (count) - 1
END WHILE
(count) ← 0
Data_Page ← (DPPx)
Enable interrupts and traps
Description
Overrides the standard DPP addressing scheme of the long and indirect addressing
modes for a specified number of instructions. During their execution, both standard and
PEC interrupts and class A hardware traps are locked. The EXTP instruction becomes
active immediately such that no additional NOPs are required. For any long (’mem’) or
indirect ([...]) address in the EXTP instruction sequence, the 10-bit page number
(address bits A23-A14) is not determined by the contents of a DPP register, but by the
value of op1 itself. The 14-bit page offset (address bits A13-A0) is derived from the long
or indirect address as usual. The value of op2 defines the length of the affected
instruction sequence.
CPU Flags
E
E
Z
V
C
N
User Manual
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
8-251
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
EXTP
EXTP
User Manual
#pag , #irang2
Rwm , #irang2
Format
D7 :01##-0 pp 0:00pp
DC :01##-m
8-252
Bytes
4
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
EXTPR
EXTPR
Begin EXTended Page and Register Sequence
Group
System Control Instructions
Syntax
EXTPR op1, op2
Source Operand(s)
op1 → 10-bit page number
op2 → 2-bit instruction counter
Destination Operand(s)
none
Operation
(count) ← (op2) [1 ≤ op2 ≤ 4]
Disable interrupts and Class A traps
Data_Page ← (op1)
SFR_range ← Extended
DO WHILE ((count) ≠ 0 AND Class_B_Trap_Condition ≠ TRUE)
Next Instruction
(count) ← (count) - 1
END WHILE
(count) ← 0
Data_Page ← (DPPx)
SFR_range ← Standard
Enable interrupts and traps
Description
Overrides the standard DPP addressing scheme of the long and indirect addressing
modes and causes all SFR or SFR bit accesses via the ’reg’, ’bitoff’ or ’bitaddr’
addressing modes being made to the Extended SFR space for a specified number of
instructions. During their execution, both standard and PEC interrupts and class A
hardware traps are locked. For any long (’mem’) or indirect ([...]) address in the EXTP
instruction sequence, the 10-bit page number (address bits A23-A14) is not determined
by the contents of a DPP register, but by the value of op1 itself. The 14-bit page offset
(address bits A13-A0) is derived from the long or indirect address as usual. The value
of op2 defines the length of the affected instruction sequence.
CPU Flags
E
E
Z
V
User Manual
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
8-253
V 1.7, 2001-01
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C166S V2
Detailed Instruction Description
C
N
Not affected.
Not affected.
Encoding
Mnemonic
EXTPR
EXTPR
User Manual
#pag , #irang2
Rwm , #irang2
Format
D7 :11##-0 pp 0:00pp
DC :11##-m
8-254
Bytes
4
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
EXTR
EXTR
Begin EXTended Register Sequence
Group
System Control Instructions
Syntax
EXTR op1
Source Operand(s)
op1 → 2-bit instruction counter
Destination Operand(s)
none
Operation
(count) ← (op1) [1 ≤ op1 ≤ 4]
Disable interrupts and Class A traps
SFR_range ← Extended
DO WHILE ((count) ≠ 0 AND Class_B_Trap_Condition ≠ TRUE)
Next Instruction
(count) ← (count) - 1
END WHILE
(count) ← 0
SFR_range ← Standard
Enable interrupts and traps
Description
Causes all SFR or SFR bit accesses via the ’reg’, ’bitoff’ or ’bitaddr’ addressing modes
being made to the Extended SFR space for a specified number of instructions. During
their execution, both standard and PEC interrupts and class A hardware traps are
locked. The value of op1 defines the length of the affected instruction sequence.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
EXTR
User Manual
#irang2
Format
D1 :10##-0
8-255
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
EXTS
EXTS
Begin EXTended Segment Sequence
Group
System Control Instructions
Syntax
EXTS op1, op2
Source Operand(s)
op1 → segment number
op2 → 2-bit instruction counter
Destination Operand(s)
none
Operation
(count) ← (op2) [1 ≤ op2 ≤ 4]
Disable interrupts and Class A traps
Data_Segment ← (op1)
DO WHILE ((count) ≠ 0 AND Class_B_Trap_Condition ≠ TRUE)
Next Instruction
(count) ← (count) - 1
END WHILE
(count) ← 0
Data_Page ← (DPPx)
Enable interrupts and traps
Description
Overrides the standard DPP addressing scheme of the long and indirect addressing
modes for a specified number of instructions. During their execution, both standard and
PEC interrupts and class A hardware traps are locked. The EXTS instruction becomes
immediately active such that no additional NOPs are required. For any long (’mem’) or
indirect ([...]) address in an EXTS instruction sequence, the value of op1 determines the
8-bit segment (address bits A23-A16) valid for the corresponding data access. The long
or indirect address itself represents the 16-bit segment offset (address bits A15-A0).
The value of op2 defines the length of the affected instruction sequence.
CPU Flags
E
E
Z
V
C
N
User Manual
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
8-256
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
EXTS
EXTS
User Manual
#seg , #irang2
Rwm , #irang2
Format
D7 :00##-0 ss 00
DC :00##-m
8-257
Bytes
4
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
EXTSR
EXTSR
Begin EXTended Segment and Register Sequence
Group
System Control Instructions
Syntax
EXTSR op1, op2
Source Operand(s)
op1 → segment number
op2 → 2-bit instruction counter
Destination Operand(s)
none
Operation
(count) ← (op2) [1 ≤ op2 ≤ 4]
Disable interrupts and Class A traps
Data_Segment ← (op1)
SFR_range ← Extended
DO WHILE ((count) ≠ 0 AND Class_B_Trap_Condition ≠ TRUE)
Next Instruction
(count) ← (count) - 1
END WHILE
(count) ← 0
Data_Page ← (DPPx)
SFR_range ← Standard
Enable interrupts and traps
Description
Overrides the standard DPP addressing scheme of the long and indirect addressing
modes and causes all SFR or SFR bit accesses via the ’reg’, ’bitoff’ or ’bitaddr’
addressing modes being made to the Extended SFR space for a specified number of
instructions. During their execution, both standard and PEC interrupts and class A
hardware traps are locked. The EXTSR instruction becomes immediately active such
that no additional NOPs are required. For any long (’mem’) or indirect ([...]) address in
an EXTSR instruction sequence, the value of op1 determines the 8-bit segment
(address bits A23-A16) valid for the corresponding data access. The long or indirect
address itself represents the 16-bit segment offset (address bits A15-A0). The value of
op2 defines the length of the affected instruction sequence.
CPU Flags
E
E
Z
User Manual
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
8-258
V 1.7, 2001-01
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C166S V2
Detailed Instruction Description
V
C
N
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
EXTSR
EXTSR
User Manual
#seg , #irang2
Rwm , #irang2
Format
D7 :10##-0 ss 00
DC :10##-m
8-259
Bytes
4
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
IDLE
Enter Idle Mode
Group
System Control Instructions
Syntax
IDLE
Source Operand(s)
none
Destination Operand(s)
none
IDLE
Operation
Enter Idle Mode
Description
This instruction causes the part to enter the idle mode. In this mode, the CPU is
powered down while the peripherals remain running. It remains powered down until a
peripheral interrupt or external interrupt occurs. To ensure that this instruction is not
accidentally executed, it is implemented as a protected instruction.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
IDLE
User Manual
Format
87 78 87 87
8-260
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
JB
JB
Relative Jump if Bit Set
Group
Jump Instructions
Syntax
JB op1, op2
Source Operand(s)
op1 → BIT
op2 → 8-bit signed displacement
Destination Operand(s)
none
Operation
IF ((op1) = 1) THEN
(IP) ← (IP) + 2*sign_extend(op2)
ELSE
Next Instruction
END IF
Description
If the bit specified by op1 is set, program execution continues at the location of the
instruction pointer IP, plus the specified displacement op2. The displacement is a 2s
complement number which is sign extended and counts the relative distance in words.
The value of the IP used in the target address calculation is the address of the
instruction following the JB instruction. If the specified bit is cleared, program execution
continues normally with the instruction following the JB instruction.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
JB
User Manual
bitaddrQ.q , rel
Format
8A QQ rr q0
8-261
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
JBC
Relative Jump if Bit Set and Clear Bit
Group
Jump Instructions
Syntax
JBC op1, op2
Source Operand(s)
op1 → BIT
op2 → 8-bit signed displacement
Destination Operand(s)
none
JBC
Operation
IF ((op1) = 1) THEN
(op1) ← 0
(IP) ← (IP) + 2*sign_extend(op2)
ELSE
Next Instruction
END IF
Description
If the bit specified by op1 is set, program execution continues at the location of the
instruction pointer IP, plus the specified displacement op2. The bit specified by op1 is
cleared, allowing implementation of semaphore operations. The displacement is a 2s
complement number which is sign extended and counts the relative distance in words.
The value of the IP used in the target address calculation is the address of the
instruction following the JBC instruction. If the specified bit was clear, program
execution continues normally with the instruction following the JBC instruction.
Note: Flags are updated by this instruction even if the branch is not executed. An explicit
write operation to the PSW register supersedes the condition flag values which are
implicitly generated by the CPU.
CPU Flags
E
0
E
Z
V
C
N
User Manual
Z
B
V
0
C
0
N
B
Always cleared.
Contains the logical negation of the previous state of the specified bit.
Always cleared.
Always cleared.
Contains the previous state of the specified bit.
8-262
V 1.7, 2001-01
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C166S V2
Detailed Instruction Description
Encoding
Mnemonic
JBC
User Manual
bitaddrQ.q , rel
Format
AA QQ rr q0
8-263
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
JMPA
JMPA
Absolute Conditional Jump
Group
Jump Instructions
Syntax
JMPA op1, op2
Alternative Syntax JMPA+ op1, op2
JMPA- op1, op2
Source Operand(s)
op1 → extended condition code
op2 → 16-bit address offset
Destination Operand(s)
none
Operation
IF ((op1) = 1) THEN
(IP) ← op2
ELSE
Next Instruction
END IF
Description
If the condition specified by op1 is met, a branch to the absolute address specified by
op2 is taken. If the condition is not met, no action is taken, and the instruction following
the JMPA instruction is executed normally. A static prediction scheme is used: if the
prediction bit ’a’ of the instruction long word is cleared then JMPA is assumed ’taken’
and if this bit is set to 1 JMPA is assumed ’not taken’. JMPA+ and JMPA- instructions
are converted into JMPA assumed ’taken’ (bit ’a’ cleared) and ’not taken’ (bit ’a’ set)
respectively. For regular JMPA instructions, the assembler applies the following rule:
cc_z is predicted ’not taken’ meanwhile all other conditions are predicted ’taken’. A
prefetch hint bit is also used. This bit is the instruction long word bit ’l’ and is required by
the fetch unit to deal efficiently with short backward loops. It must be set only if
(0 < IP_jmpa - IP_target ≤ 32), cleared otherwise. IP_jmpa is the address of the JMPA
instruction and IP_target is the target address of JMPA.
CPU Flags
E
E
Z
V
User Manual
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
8-264
V 1.7, 2001-01
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C166S V2
Detailed Instruction Description
C
N
Not affected.
Not affected.
Encoding
Mnemonic
JMPA
User Manual
xcc , caddr
Format
EA d0la MM MM
8-265
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
JMPI
JMPI
Indirect Conditional Jump
Group
Jump Instructions
Syntax
JMPI op1, op2
Source Operand(s)
op1 → condition code
op2 → 16-bit address offset
Destination Operand(s)
none
Operation
IF ((op1) = 1) THEN
(IP) ← (op2)
ELSE
Next Instruction
END IF
Description
If the condition specified by op1 is met, a branch to the absolute address specified by
op2 is taken. If the condition is not met, no action is taken, and program execution
continues normally with the instruction following the JMPI instruction.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
JMPI
User Manual
cc , [Rwn]
Format
9C cn
8-266
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
JMPR
JMPR
Relative Conditional Jump
Group
Jump Instructions
Syntax
JMPR op1, op2
Source Operand(s)
op1 → condition code
op2 → 8-bit signed displacement
Destination Operand(s)
none
Operation
IF ((op1) = 1) THEN
(IP) ← (IP) + 2*sign_extend(op2)
ELSE
Next Instruction
END IF
Description
If the extended condition specified by op1 is met, program execution continues at the
location of the instruction pointer, IP, plus the specified displacement, op2. The
displacement is a 2s complement number which is sign-extended and counts the
relative distance in words. The value of the IP used in the target address calculation is
the address of the instruction following the JMPR instruction. If the specified condition is
not met, program execution continues normally with the instruction following the JMPR
instruction.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
JMPR
User Manual
cc , rel
Format
cD rr
8-267
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
JMPS
JMPS
Absolute Inter-Segment Jump
Group
Jump Instructions
Syntax
JMPS op1, op2
Source Operand(s)
op1 → segment number
op2 → 16-bit address offset
Destination Operand(s)
none
Operation
IF (CPUCON1.SGTDIS = 0) THEN
(CSP) ← op1
END IF
(IP) ← op2
Description
Branches unconditionally to the absolute address specified by op2 within the segment
specified by op1.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
JMPS
User Manual
seg , caddr
Format
FA SS MM MM
8-268
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
JNB
JNB
Relative Jump if Bit Clear
Group
Jump Instructions
Syntax
JNB op1, op2
Source Operand(s)
op1 → BIT
op2 → 8-bit signed displacement
Destination Operand(s)
none
Operation
IF ((op1) = 0) THEN
(IP) ← (IP) + 2*sign_extend(op2)
ELSE
Next Instruction
END IF
Description
If the bit specified by op1 is clear, program execution continues at the location of the
instruction pointer IP, plus the specified displacement op2. The displacement is a 2s
complement number which is sign-extended and counts the relative distance in words.
The value of the IP used in the target address calculation is the address of the
instruction following the JNB instruction. If the specified bit is set, program execution
continues normally with the instruction following the JNB instruction.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
JNB
User Manual
bitaddrQ.q , rel
Format
9A QQ rr q0
8-269
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
JNBS
Relative Jump if Bit Clear and Set Bit
Group
Jump Instructions
Syntax
JNBS op1, op2
Source Operand(s)
op1 → BIT
op2 → 8-bit signed displacement
Destination Operand(s)
none
JNBS
Operation
IF ((op1) = 0) THEN
(op1) ← 1
(IP) ← (IP) + 2*sign_extend(op2)
ELSE
Next Instruction
END IF
Description
If the bit specified by op1 is clear, program execution continues at the location of the
instruction pointer IP, plus the specified displacement op2. The bit specified by op1 is
set, allowing implementation of semaphore operations. The displacement is a 2s
complement number which is sign-extended and counts the relative distance in words.
The value of the IP used in the target address calculation is the address of the
instruction following the JNBS instruction. If the specified bit was set, program
execution continues normally with the instruction following the JNBS instruction.
Note: Flags are updated by this instruction even if the branch is not executed. An explicit
write operation to the PSW register supersedes the condition flag values which are
implicitly generated by the CPU.
CPU Flags
E
0
E
Z
V
C
N
User Manual
Z
B
V
0
C
0
N
B
Always cleared.
Contains the logical negation of the previous state of the specified bit.
Always cleared.
Always cleared.
Contains the previous state of the specified bit.
8-270
V 1.7, 2001-01
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C166S V2
Detailed Instruction Description
Encoding
Mnemonic
JNBS
User Manual
bitaddrQ.q , rel
Format
BA QQ rr q0
8-271
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
MOV
MOV
Move Data
Group
Data Movement Instructions
Syntax
MOV op1, op2
Source Operand(s)
op2 → WORD
Destination Operand(s)
op1 → WORD
Operation
(op1) ← (op2)
Description
Moves the contents of the source operand specified by op2 to the location specified by
the destination operand op1. The contents of the moved data are examined, and the
flags are updated accordingly.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
-
C
-
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if the value of the source operand op2 equals zero. Cleared
otherwise.
Not affected.
Not affected.
Set if the most significant bit of the source operand op2 is set. Cleared
otherwise.
Encoding
Mnemonic
MOV
MOV
MOV
MOV
MOV
MOV
MOV
User Manual
Rwn , #data4
Rwn , Rwm
Rwn , [Rwm+#data16]
Rwn , [Rwm+]
Rwn , [Rwm]
[-Rwm] , Rwn
[Rwm+#data16] , Rwn
Format
E0 #n
F0 nm
D4 nm ## ##
98 nm
A8 nm
88 nm
C4 nm ## ##
8-272
Bytes
2
2
4
2
2
2
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
MOV
MOV
MOV
MOV
MOV
MOV
MOV
MOV
MOV
User Manual
[Rwm] , Rwn
[Rwn+] , [Rwm]
[Rwn] , [Rwm+]
[Rwn] , [Rwm]
[Rwn] , mem
mem , [Rwn]
mem , reg
reg , #data16
reg , mem
B8 nm
D8 nm
E8 nm
C8 nm
84 0n MM MM
94 0n MM MM
F6 RR MM MM
E6 RR ## ##
F2 RR MM MM
8-273
2
2
2
2
4
4
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
MOVB
MOVB
Move Data
Group
Data Movement Instructions
Syntax
MOVB op1, op2
Source Operand(s)
op2 → BYTE
Destination Operand(s)
op1 → BYTE
Operation
(op1) ← (op2)
Description
Moves the contents of the source operand specified by op2 to the location specified by
the destination operand op1. The contents of the moved data are examined, and the
flags are updated accordingly.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
-
C
-
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if the value of the source operand op2 equals zero. Cleared
otherwise.
Not affected.
Not affected.
Set if the most significant bit of the source operand op2 is set. Cleared
otherwise.
Encoding
Mnemonic
MOVB
MOVB
MOVB
MOVB
MOVB
MOVB
MOVB
User Manual
Rbn , #data4
Rbn , Rbm
Rbn , [Rwm + #data16]
Rbn , [Rwm+]
Rbn , [Rwm]
[-Rwm] , Rbn
[Rwm + #data16] , Rbn
Format
E1 #n
F1 nm
F4 nm ## ##
99 nm
A9 nm
89 nm
E4 nm ## ##
8-274
Bytes
2
2
4
2
2
2
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
MOVB
MOVB
MOVB
MOVB
MOVB
MOVB
MOVB
MOVB
MOVB
User Manual
[Rwm] , Rbn
[Rwn+] , [Rwm]
[Rwn] , [Rwm+]
[Rwn] , [Rwm]
[Rwn] , mem
mem , [Rwn]
mem , reg
reg , #data8
reg , mem
B9 nm
D9 nm
E9 nm
C9 nm
A4 0n MM MM
B4 0n MM MM
F7 RR MM MM
E7 RR ## xx
F3 RR MM MM
8-275
2
2
2
2
4
4
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
MOVBS
MOVBS
Move Byte Sign Extend
Group
Data Movement Instructions
Syntax
MOVBS op1, op2
Source Operand(s)
op2 → BYTE
Destination Operand(s)
op1 → WORD
Operation
(low byte op1) ← (op2)
IF ((op2[7]) = 1) THEN
(high byte op1) ← FFH
ELSE
(high byte op1) ← 00H
END IF
Description
Moves and sign-extends the contents of the source byte operand specified by op2 to
the word location specified by the destination operand op1. The contents of the moved
data are examined, and the flags are updated accordingly.
CPU Flags
E
0
E
Z
V
C
N
Z
*
V
-
C
-
N
*
Always cleared.
Set if the value of the source byte operand op2 equals zero. Cleared
otherwise.
Not affected.
Not affected.
Set if the most significant bit of the source operand op2 is set. Cleared
otherwise.
Encoding
Mnemonic
MOVBS
MOVBS
MOVBS
User Manual
Rwn , Rbm
mem , reg
reg , mem
Format
D0 mn
D5 RR MM MM
D2 RR MM MM
8-276
Bytes
2
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
MOVBZ
MOVBZ
Move Byte Zero Extend
Group
Data Movement Instructions
Syntax
MOVBZ op1, op2
Source Operand(s)
op2 → BYTE
Destination Operand(s)
op1 → WORD
Operation
(low byte op1) ← (op2)
(high byte op1) ← 00H
Description
Moves and zero-extends the contents of the source byte operand specified by op2 to
the word location specified by the destination operand op1. The contents of the moved
data are examined, and the flags are updated accordingly.
CPU Flags
E
0
E
Z
V
C
N
Z
*
V
-
C
-
N
0
Always cleared.
Set if the value of the source byte operand op2 equals zero. Cleared
otherwise.
Not affected.
Not affected.
Always cleared.
Encoding
Mnemonic
MOVBZ
MOVBZ
MOVBZ
User Manual
Rwn , Rbm
mem , reg
reg , mem
Format
C0 mn
C5 RR MM MM
C2 RR MM MM
8-277
Bytes
2
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
MUL
MUL
Signed Multiplication
Group
Arithmetic Instructions
Syntax
MUL op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
MD → DOUBLEWORD
Operation
(MD) ← (op1) * (op2)
Description
Performs a 16-bit by 16-bit signed multiplication using the two words specified by
operands op1 and op2 respectively. The signed 32-bit result is placed in the MD
register.
CPU Flags
E
0
E
Z
V
C
N
Z
*
V
*
C
0
N
*
Always cleared.
Set if result equals zero. Cleared otherwise.
This bit is set if the result cannot be represented in a word data type.
Cleared otherwise.
Always cleared.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
MUL
User Manual
Rwn , Rwm
Format
0B nm
8-278
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
MULU
MULU
Unsigned Multiplication
Group
Arithmetic Instructions
Syntax
MULU op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
MD → DOUBLEWORD
Operation
(MD) ← (op1) * (op2)
Description
Performs a 16-bit by 16-bit unsigned multiplication using the two words specified by
operands op1 and op2 respectively. The unsigned 32-bit result is placed in the MD
register.
CPU Flags
E
0
E
Z
V
C
N
Z
*
V
*
C
0
N
*
Always cleared.
Set if result equals zero. Cleared otherwise.
This bit is set if the result cannot be represented in a word data type.
Cleared otherwise.
Always cleared.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
MULU
User Manual
Rwn , Rwm
Format
1B nm
8-279
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
NEG
NEG
Integer Two’s Complement
Group
Arithmetic Instructions
Syntax
NEG op1
Source Operand(s)
op1 → WORD
Destination Operand(s)
op1 → WORD
Operation
(op1) ← 0 - (op1)
Description
Performs a binary 2s complement of the source operand specified by op1. The result is
then stored in op1.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
*
C
*
N
*
Set if the value of op1 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the word data type. Cleared otherwise.
Set if a borrow is generated. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
NEG
User Manual
Rwn
Format
81 n0
8-280
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
NEGB
NEGB
Integer Two’s Complement
Group
Arithmetic Instructions
Syntax
NEGB op1
Source Operand(s)
op1 → BYTE
Destination Operand(s)
op1 → BYTE
Operation
(op1) ← 0 - (op1)
Description
Performs a binary 2s complement of the source operand specified by op1. The result is
then stored in op1.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
*
C
*
N
*
Set if the value of op1 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the byte data type. Cleared otherwise.
Set if a borrow is generated. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
NEGB
User Manual
Rbn
Format
A1 n0
8-281
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
NOP
NOP
No Operation
Group
Null operation
Syntax
NOP
Source Operand(s)
none
Destination Operand(s)
none
Operation
No Operation
Description
This instruction causes a null operation to be performed. A null operation causes no
change in the status of the flags.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
NOP
User Manual
Format
CC 00
8-282
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
OR
OR
Logical OR
Group
Logical Instructions
Syntax
OR op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
op1 → WORD
Operation
(op1) ← (op1) ∨ (op2)
Description
Performs a bitwise logical OR of the source operand specified by op2 and the
destination operand specified by op1. The result is then stored in op1.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
0
C
0
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Always cleared.
Always cleared.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
OR
OR
OR
OR
OR
OR
OR
User Manual
Rwn , #data3
Rwn , Rwm
Rwn , [Rwi+]
Rwn , [Rwi]
mem , reg
reg , #data16
reg , mem
Format
78 n:0###
70 nm
78 n:11ii
78 n:10ii
74 RR MM MM
76 RR ## ##
72 RR MM MM
8-283
Bytes
2
2
2
2
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
ORB
ORB
Logical OR
Group
Logical Instructions
Syntax
ORB op1, op2
Source Operand(s)
op1, op2 → BYTE
Destination Operand(s)
op1 → BYTE
Operation
(op1) ← (op1) ∨ (op2)
Description
Performs a bitwise logical OR of the source operand specified by op2 and the
destination operand specified by op1. The result is then stored in op1.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
0
C
0
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Always cleared.
Always cleared.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
ORB
ORB
ORB
ORB
ORB
ORB
ORB
User Manual
Rbn , #data3
Rbn , Rbm
Rbn , [Rwi+]
Rbn , [Rwi]
mem , reg
reg , #data8
reg , mem
Format
79 n:0###
71 nm
79 n:11ii
79 n:10ii
75 RR MM MM
77 RR ## xx
73 RR MM MM
8-284
Bytes
2
2
2
2
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
PCALL
Push Word and Call Subroutine Absolute
Group
Call Instructions
Syntax
PCALL op1, op2
Source Operand(s)
op1 → WORD
op2 → 16-bit address offset
Destination Operand(s)
none
PCALL
Operation
(tmp) ← (op1)
(SP) ← (SP) - 2
((SP)) ← (tmp)
(SP) ← (SP) - 2
((SP)) ← (IP)
(IP) ← op2
Description
Pushes the word specified by operand op1 and the value of the instruction pointer, IP,
onto the system stack, and branches to the absolute memory location specified by the
second operand op2. Because IP always points to the instruction following the branch
instruction, the value stored on the system stack represents the return address of the
calling routine.
CPU Flags
E
*
E
Z
V
C
N
User Manual
Z
*
V
-
C
-
N
*
Set if the value of the pushed operand op1 represents the lowest
possible negative number. Cleared otherwise. Used to signal the end of a
table.
Set if the value of the pushed operand op1 equals zero. Cleared
otherwise.
Not affected.
Not affected.
Set if the most significant bit of the pushed operand op1 is set. Cleared
otherwise.
8-285
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
PCALL
User Manual
reg , caddr
Format
E2 RR MM MM
8-286
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
POP
POP
Pop Word from System Stack
Group
System Stack Instructions
Syntax
POP op1
Source Operand(s)
none
Destination Operand(s)
op1 → WORD
Operation
(tmp) ← ((SP))
(SP) ← (SP) + 2
(op1) ← (tmp)
Description
Pops one word from the system stack specified by the Stack Pointer into the operand
specified by op1. The Stack Pointer is then incremented by two.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
-
C
-
N
*
Set if the value of the popped word represents the lowest possible
negative number. Cleared otherwise. Used to signal the end of a table.
Set if the value of the popped word equals zero. Cleared otherwise.
Not affected.
Not affected.
Set if the most significant bit of the popped word is set. Cleared
otherwise.
Encoding
Mnemonic
POP
User Manual
reg
Format
FC RR
8-287
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
PRIOR
PRIOR
Prioritize Register
Group
Prioritize Instruction
Syntax
PRIOR op1, op2
Source Operand(s)
op2 → WORD
Destination Operand(s)
op1 → WORD
Operation
(tmp) ← (op2)
(count) ← 0
DO WHILE (((tmp[15]) ≠ 1) AND ((op2) ≠ 0)))
(tmp[n]) ← (tmp[n-1]) [n=15...1]
(count) ← (count) + 1
END WHILE
(op1) ← (count)
Description
This instruction stores a count value in the word operand specified by op1. This count
value indicates the number of single bit shifts required to normalize the word operand
op2 so that its most significant bit is equal to one. If the source operand op2 equals
zero, a zero is written to operand op1 and the zero flag is set. Otherwise, the zero flag is
cleared.
CPU Flags
E
0
E
Z
V
C
N
Z
*
V
0
C
0
N
0
Always cleared.
Set if the value of the source operand op2 equals zero. Cleared
otherwise.
Always cleared.
Always cleared.
Always cleared.
Encoding
Mnemonic
PRIOR
User Manual
Rwn , Rwm
Format
2B nm
8-288
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
PUSH
PUSH
Push Word on System Stack
Group
System Stack Instructions
Syntax
PUSH op1
Source Operand(s)
op1 → WORD
Destination Operand(s)
none
Operation
(tmp) ← (op1)
(SP) ← (SP) - 2
((SP)) ← (tmp)
Description
Moves the word specified by operand op1 to the location in the system stack specified
by the Stack Pointer, after the Stack Pointer has been decremented by two.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
-
C
-
N
*
Set if the value of the pushed operand op1 represents the lowest
possible negative number. Cleared otherwise. Used to signal the end of a
table.
Set if the value of the pushed operand op1 equals zero. Cleared
otherwise.
Not affected.
Not affected.
Set if the most significant bit of the pushed operand op1 is set. Cleared
otherwise.
Encoding
Mnemonic
PUSH
User Manual
reg
Format
EC RR
8-289
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
PWRDN
PWRDN
Enter Power Down Mode
Group
System Control Instructions
Syntax
PWRDN
Source Operand(s)
none
Destination Operand(s)
none
Operation
Enter Power Down Mode
Description
This instruction causes the device to enter the power down mode. In this mode, all
peripherals and the CPU are powered down until the device is externally reset. To
ensure that this instruction is not accidentally executed, it is implemented as a
protected instruction. To further control the action of this instruction, the PWRDN
instruction is only enabled when the non-maskable interrupt pin (NMI) is in the low
state. Otherwise, this instruction has no effect.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
PWRDN
User Manual
Format
97 68 97 97
8-290
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
RET
RET
Return from Subroutine
Group
Return Instructions
Syntax
RET
Source Operand(s)
none
Destination Operand(s)
none
Operation
(IP) ← ((SP))
(SP) ← (SP) + 2
Description
Returns from a subroutine. The IP is popped from the system stack.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
RET
User Manual
Format
CB 00
8-291
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
RETI
RETI
Return from Interrupt Subroutine
Group
Return Instructions
Syntax
RETI
Source Operand(s)
none
Destination Operand(s)
none
Operation
(IP) ← ((SP))
(SP) ← (SP) + 2
IF (CPUCON1.SGTDIS = 0) THEN
(CSP) ← ((SP))
(SP) ← (SP) + 2
END IF
(PSW) ← ((SP))
(SP) ← (SP) + 2
Description
Returns from an interrupt routine. The IP, CSP, and PSW are popped off the system
stack. The CSP is only popped if segmentation is enabled. This is indicated by the
SGTDIS bit in the CPUCON1 register.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
*
C
*
N
*
Restored from the PSW popped from stack.
Restored from the PSW popped from stack.
Restored from the PSW popped from stack.
Restored from the PSW popped from stack.
Restored from the PSW popped from stack.
Encoding
Mnemonic
RETI
User Manual
Format
FB 88
8-292
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
RETP
Return from Subroutine and Pop Word
Group
Return Instructions
Syntax
RETP op1
Source Operand(s)
none
Destination Operand(s)
op1 → WORD
RETP
Operation
(IP) ← ((SP))
(SP) ← (SP) + 2
(tmp) ← ((SP))
(SP) ← (SP) + 2
(op1) ← (tmp)
Description
Returns from a subroutine. First the IP is popped from the system stack and then the
next word is popped from the system stack into the operand specified by op1.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
-
C
-
N
*
Set if the value of the popped word represents the lowest possible
negative number. Cleared otherwise. Used to signal the end of a table.
Set if the value of the popped word equals zero. Cleared otherwise.
Not affected.
Not affected.
Set if the most significant bit of the popped word is set. Cleared
otherwise.
Encoding
Mnemonic
RETP
User Manual
reg
Format
EB RR
8-293
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
RETS
Return from Inter-Segment Subroutine
Group
Return Instructions
Syntax
RETS
Source Operand(s)
none
Destination Operand(s)
none
RETS
Operation
(IP) ← ((SP))
(SP) ← (SP) + 2
IF (CPUCON1.SGTDIS = 0) THEN
(CSP) ← ((SP))
END IF
(SP) ← (SP) + 2
Description
Returns from an inter-segment subroutine. The IP and CSP are popped from the
system stack.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
RETS
User Manual
Format
DB 00
8-294
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
ROL
ROL
Rotate Left
Group
Shift and Rotate Instructions
Syntax
ROL op1, op2
Source Operand(s)
op1 → WORD
op2 → shift counter
Destination Operand(s)
op1 → WORD
Operation
(count) ← (op2)
(C) ← 0
DO WHILE ((count) ≠ 0)
(C) ← (op1[15])
(op1[n]) ← (op1[n-1]) [n=15...1]
(op1[0]) ← (C)
(count) ← (count) - 1
END WHILE
Description
Rotates the destination word operand op1 the number of times as specified by the
source operand op2. Bit 15 is rotated into Bit 0 and into the Carry. Only shift values
between 0 and 15 are allowed. When using a GPR as the count control, only the least
significant four bits are used.
CPU Flags
E
0
E
Z
V
C
N
User Manual
Z
*
V
0
C
S
N
*
Always cleared.
Set if result equals zero. Cleared otherwise.
Always cleared.
The carry flag is set according to the last most significant bit shifted out of
op1. Cleared for a shift count of zero.
Set if the most significant bit of the result is set. Cleared otherwise.
8-295
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
ROL
ROL
User Manual
Rwn , #data4
Rwn , Rwm
Format
1C #n
0C nm
8-296
Bytes
2
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
ROR
ROR
Rotate Right
Group
Shift and Rotate Instructions
Syntax
ROR op1, op2
Source Operand(s)
op1 → WORD
op2 → shift counter
Destination Operand(s)
op1 → WORD
Operation
(count) ← (op2)
(C) ← 0
(V) ← 0
DO WHILE ((count) ≠ 0)
(V) ← (V) ∨ (C)
(C) ← (op1[0])
(op1[n]) ← (op1[n+1]) [n=0...14]
(op1[15]) ← (C)
(count) ← (count) - 1
END WHILE
Description
Rotates the destination word operand op1 right by the number of times as specified by
the source operand op2. Bit 0 is rotated into Bit 15 and into the Carry. Only shift values
between 0 and 15 are allowed. When using a GPR as the count control, only the least
significant four bits are used.
CPU Flags
E
0
E
Z
V
C
N
User Manual
Z
*
V
S
C
S
N
*
Always cleared.
Set if result equals zero. Cleared otherwise.
Set if in any cycle of the rotate operation a 1 is shifted out of the carry
flag. Cleared for a rotate count of zero.
The carry flag is set according to the last least significant bit shifted out of
op1. Cleared for a shift count of zero.
Set if the most significant bit of the result is set. Cleared otherwise.
8-297
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
ROR
ROR
User Manual
Rwn , #data4
Rwn , Rwm
Format
3C #n
2C nm
8-298
Bytes
2
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
SBRK
SBRK
Software Break
Group
System Control Instructions
Syntax
SBRK
Source Operand(s)
none
Destination Operand(s)
none
Operation
Software Break
Description
If the SBRK instruction is enabled by the One Chip Emulator (OCE), then the break
mode is activated. If SBRK is not enabled by the OCE, then the hardware trap "soft
break" (Class A, Vector 8) is activated. For more details about this instruction, see the
OCE specifications.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
SBRK
User Manual
Format
8C 00
8-299
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
SCXT
SCXT
Switch Context
Group
System Stack Instructions
Syntax
SCXT op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
op1 → WORD
Operation
(tmp1) ← (op1)
(tmp2) ← (op2)
(SP) ← (SP) - 2
((SP)) ← (tmp1)
(op1) ← (tmp2)
Description
Switches contexts of any register. Switching context is a push and load operation. The
contents of the register specified by the first operand op1, are pushed onto the stack.
That register is then loaded with the value specified by the second operand, op2.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
SCXT
SCXT
User Manual
reg , #data16
reg , mem
Format
C6 RR ## ##
D6 RR MM MM
8-300
Bytes
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
SHL
SHL
Shift Left
Group
Shift and Rotate Instructions
Syntax
SHL op1, op2
Source Operand(s)
op1 → WORD
op2 → shift counter
Destination Operand(s)
op1 → WORD
Operation
(count) ← (op2)
(C) ← 0
DO WHILE ((count) ≠ 0)
(C) ← (op1[15])
(op1[n]) ← (op1[n-1]) [n=15...1]
(op1[0]) ← 0
(count) ← (count) - 1
END WHILE
Description
Shifts the destination word operand op1 the number of times as specified by the source
operand op2. The least significant bits of the result are filled with zeros accordingly. The
most significant bit is shifted into the Carry. Only shift values between 0 and 15 are
allowed. When using a GPR as the count control, only the least significant four bits are
used.
CPU Flags
E
0
E
Z
V
C
N
User Manual
Z
*
V
0
C
S
N
*
Always cleared.
Set if result equals zero. Cleared otherwise.
Always cleared.
The carry flag is set according to the last most significant bit shifted out of
op1. Cleared for a shift count of zero.
Set if the most significant bit of the result is set. Cleared otherwise.
8-301
V 1.7, 2001-01
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C166S V2
Detailed Instruction Description
Encoding
Mnemonic
SHL
SHL
User Manual
Rwn , #data4
Rwn , Rwm
Format
5C #n
4C nm
8-302
Bytes
2
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
SHR
SHR
Shift Right
Group
Shift and Rotate Instructions
Syntax
SHR op1, op2
Source Operand(s)
op1 → WORD
op2 → shift counter
Destination Operand(s)
op1 → WORD
Operation
(count) ← (op2)
(C) ← 0
(V) ← 0
DO WHILE ((count) ≠ 0)
(V) ← (C) ∨ (V)
(C) ← (op1[0])
(op1[n]) ← (op1[n+1]) [n=0...14]
(op1[15]) ← 0
(count) ← (count) - 1
END WHILE
Description
Shifts the destination word operand op1 right by the number of times as specified by the
source operand op2. The most significant bits of the result are filled with zeros
accordingly. Since the bits shifted out effectively represent the remainder, the Overflow
flag is used instead as a Rounding flag. A shift right is a division by a power of two. The
overflow flag with the carry flag allows determination of whether the fractional part of the
division result is greater than, less than, or equal to one half (0.5 in decimal base). This
allows rounding of the division result accordingly. Only shift values between 0 and 15
are allowed. When using a GPR as the count control, only the least significant four bits
are used.
CPU Flags
E
0
E
Z
V
User Manual
Z
*
V
S
C
S
N
*
Always cleared.
Set if result equals zero. Cleared otherwise.
Set if in any cycle of the shift operation a 1 is shifted out of the carry flag.
Cleared in case of a shift count equal 0.
8-303
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
C
N
The carry flag is set according to the last least significant bit shifted out of
op1. Cleared for a shift count of zero.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
SHR
SHR
User Manual
Rwn , #data4
Rwn , Rwm
Format
7C #n
6C nm
8-304
Bytes
2
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
SRST
SRST
Software Reset
Group
System Control Instructions
Syntax
SRST
Source Operand(s)
none
Destination Operand(s)
none
Operation
Software Reset
Description
This instruction is used to perform a software reset. A software reset has the same
effect on the microcontroller as an externally applied hardware reset. To ensure that
this instruction is not accidentally executed, it is implemented as a protected instruction.
CPU Flags
E
0
E
Z
V
C
N
Z
0
V
0
C
0
N
0
Always cleared.
Always cleared.
Always cleared.
Always cleared.
Always cleared.
Encoding
Mnemonic
SRST
User Manual
Format
B7 48 B7 B7
8-305
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
SRVWDT
SRVWDT
Service Watchdog Timer
Group
System Control Instructions
Syntax
SRVWDT
Source Operand(s)
none
Destination Operand(s)
none
Operation
Service Watchdog Timer
Description
This instruction reloads the high order byte of the Watchdog Timer with a preset value
and clears the low byte. After this instruction has been executed and if the WDTCTL bit
of the CPUCON1 register is cleared, the Watchdog Timer cannot be disabled
regardless of the execution of SRVWDT. If the WDTCTL bit is set, the Watchdog Timer
can still be disabled. To ensure that this instruction is not accidentally executed, it is
implemented as a protected instruction.
CPU Flags
E
E
Z
V
C
N
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
SRVWDT
User Manual
Format
A7 58 A7 A7
8-306
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
SUB
SUB
Integer Subtraction
Group
Arithmetic Instructions
Syntax
SUB op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
op1 → WORD
Operation
(op1) ← (op1) - (op2)
Description
Performs a 2s complement binary subtraction of the source operand specified by op2
and the destination operand specified by op1. The result is then stored in op1.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
*
C
S
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the word data type. Cleared otherwise.
Set if a borrow is generated. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
SUB
SUB
SUB
SUB
SUB
SUB
SUB
User Manual
Rwn , #data3
Rwn , Rwm
Rwn , [Rwi+]
Rwn , [Rwi]
mem , reg
reg , #data16
reg , mem
Format
28 n:0###
20 nm
28 n:11ii
28 n:10ii
24 RR MM MM
26 RR ## ##
22 RR MM MM
8-307
Bytes
2
2
2
2
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
SUBB
SUBB
Integer Subtraction
Group
Arithmetic Instructions
Syntax
SUBB op1, op2
Source Operand(s)
op1, op2 → BYTE
Destination Operand(s)
op1 → BYTE
Operation
(op1) ← (op1) - (op2)
Description
Performs a 2s complement binary subtraction of the source operand specified by op2
and the destination operand specified by op1. The result is then stored in op1.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
*
C
S
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the word data type. Cleared otherwise.
Set if a borrow is generated. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
SUBB
SUBB
SUBB
SUBB
SUBB
SUBB
SUBB
User Manual
Rbn , #data3
Rbn , Rbm
Rbn , [Rwi+]
Rbn , [Rwi]
mem , reg
reg , #data8
reg , mem
Format
29 n:0###
21 nm
29 n:11ii
29 n:10ii
25 RR MM MM
27 RR ## xx
23 RR MM MM
8-308
Bytes
2
2
2
2
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
SUBC
SUBC
Integer Subtraction with Carry
Group
Arithmetic Instructions
Syntax
SUBC op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
op1 → WORD
Operation
(op1) ← (op1) - (op2) - (C)
Description
Performs a 2s complement binary subtraction of the source operand specified by op2
and the previously generated carry bit from the destination operand specified by op1.
The result is then stored in op1. This instruction can be used to perform multiple
precision arithmetic.
CPU Flags
E
*
E
Z
V
C
N
Z
S
V
*
C
S
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero and previous Z flag was set. Cleared otherwise.
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the word data type. Cleared otherwise.
Set if a borrow is generated. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
SUBC
SUBC
SUBC
SUBC
SUBC
SUBC
SUBC
User Manual
Rwn , #data3
Rwn , Rwm
Rwn , [Rwi+]
Rwn , [Rwi]
mem , reg
reg , #data16
reg , mem
Format
38 n:0###
30 nm
38 n:11ii
38 n:10ii
34 RR MM MM
36 RR ## ##
32 RR MM MM
8-309
Bytes
2
2
2
2
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
SUBCB
SUBCB
Integer Subtraction with Carry
Group
Arithmetic Instructions
Syntax
SUBCB op1, op2
Source Operand(s)
op1, op2 → BYTE
Destination Operand(s)
op1 → BYTE
Operation
(op1) ← (op1) - (op2) - (C)
Description
Performs a 2s complement binary subtraction of the source operand specified by op2
and the previously generated carry bit from the destination operand specified by op1.
The result is then stored in op1. This instruction can be used to perform multiple
precision arithmetic.
CPU Flags
E
*
E
Z
V
C
N
Z
S
V
*
C
S
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero and the previous Z flag was set. Cleared
otherwise.
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the word data type. Cleared otherwise.
Set if a borrow is generated. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
SUBCB
SUBCB
SUBCB
SUBCB
SUBCB
SUBCB
SUBCB
User Manual
Rbn , #data3
Rbn , Rbm
Rbn , [Rwi+]
Rbn , [Rwi]
mem , reg
reg , #data8
reg , mem
Format
39 n:0###
31 nm
39 n:11ii
39 n:10ii
35 RR MM MM
37 RR ## xx
33 RR MM MM
8-310
Bytes
2
2
2
2
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
TRAP
TRAP
Software Trap
Group
Call Instructions
Syntax
TRAP op1
Source Operand(s)
op1 → 7-bit trap number
Destination Operand(s)
none
Operation
(SP) ← (SP) - 2
((SP) ← (PSW)
IF (CPUCON1.SGTDIS = 0) THEN
(SP) ← (SP) - 2
((SP)) ← (CSP)
END IF
(CSP) ← (VSEG)
(SP) ← (SP) - 2
((SP)) ← (IP)
(IP) ← ((op1) * 4) <<CPUCON1.SCINT
Description
Invokes a trap or interrupt routine based on the specified operand op1. The invoked
routine is determined by branching to the specified vector table entry point. This routine
has no indication of whether it was called by software or hardware. System state is
preserved identically to hardware interrupt entry except that the CPU priority level is not
affected. The RETI, Return from Interrupt instruction is used to resume execution after
the completion of the trap or interrupt routine. The CSP is pushed if the segmentation is
enabled. This is indicated by the SGTDIS bit of the CPUCON1 register.
CPU Flags
E
E
Z
V
C
N
User Manual
Z
-
V
-
C
-
N
-
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
8-311
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
TRAP
User Manual
#trap7
Format
9B t:ttt0
8-312
Bytes
2
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
XOR
XOR
Logical Exclusive OR
Group
Logical Instructions
Syntax
XOR op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
op1 → WORD
Operation
(op1) ← (op1) ⊕ (op2)
Description
Performs a bitwise logical EXCLUSIVE OR of the source operand specified by op2 and
the destination operand specified by op1. The result is then stored in op1.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
0
C
0
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Always cleared.
Always cleared.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
XOR
XOR
XOR
XOR
XOR
XOR
XOR
User Manual
Rwn , #data3
Rwn , Rwm
Rwn , [Rwi+]
Rwn , [Rwi]
mem , reg
reg , #data16
reg , mem
Format
58 n:0###
50 nm
58 n:11ii
58 n:10ii
54 RR MM MM
56 RR ## ##
52 RR MM MM
8-313
Bytes
2
2
2
2
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
XORB
XORB
Logical Exclusive OR
Group
Logical Instructions
Syntax
XORB op1, op2
Source Operand(s)
op1, op2 → BYTE
Destination Operand(s)
op1 → BYTE
Operation
(op1) ← (op1) ⊕ (op2)
Description
Performs a bitwise logical EXCLUSIVE OR of the source operand specified by op2 and
the destination operand specified by op1. The result is then stored in op1.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
0
C
0
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if result equals zero. Cleared otherwise.
Always cleared.
Always cleared.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
XORB
XORB
XORB
XORB
XORB
XORB
XORB
User Manual
Rbn , #data3
Rbn , Rbm
Rbn , [Rwi+]
Rbn , [Rwi]
mem , reg
reg , #data8
reg , mem
Format
59 n:0###
51 nm
59 n:11ii
59 n:10ii
55 RR MM MM
57 RR ## xx
53 RR MM MM
8-314
Bytes
2
2
2
2
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
8.2
User Manual
DSP Instruction Set
8-315
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoABS
CoABS
Absolute Value
Group
Arithmetic Instructions
Syntax
CoABS
Source Operand(s)
ACC → 40-bit signed value
Destination Operand(s)
ACC → 40-bit signed value
Operation
(ACC) ← Abs(ACC)
Description
Computes the absolute value of the 40-bit ACC contents.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
0
MZ
*
MN
*
Sat.
yes
MV
MSL
Set if the ACC contents was 80 0000 0000H. Cleared otherwise.
Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if the ACC contents was 80 0000 0000H. Not affected otherwise.
MC
Always cleared.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoABS
User Manual
Format
A3 00 1A rrr0:0000
8-316
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoABS
CoABS
Absolute Value
Group
Arithmetic Instructions
Syntax
CoABS op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(ACC) ← Abs((op2) || (op1))
Description
Computes the absolute value of a 40-bit source operand and loads the result in the
40-bit ACC register. The 40-bit operand is a sign-extended result of the concatenation
of the two source operands op1 (LSW) and op2 (MSW).
MAC Flags
MV
0
MSL
*
ME
*
MSV
-
MC
0
MZ
*
MN
*
Sat.
yes
MV
MSL
Always cleared.
Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Not affected.
MC
Always cleared.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoABS
CoABS
CoABS
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm CA rrr0:0000
83 nm CA rrr0:0qqq
93 Xm CA rrr0:0qqq
8-317
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoADD
CoADD
Add
Group
Arithmetic Instructions
Syntax
CoADD op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op2) || (op1)
(ACC) ← (ACC) + (tmp)
Description
Adds a 40-bit operand to the 40-bit ACC register contents and stores the result in the
ACC register. The 40-bit operand is a sign-extended result of the concatenation of the
two source operands op1 (LSW) and op2 (MSW).
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoADD
CoADD
CoADD
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 02 rrr0:0000
83 nm 02 rrr0:0qqq
93 Xm 02 rrr0:0qqq
8-318
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoADD2
CoADD2
Add
Group
Arithmetic Instructions
Syntax
CoADD2 op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← 2 * ((op2) || (op1))
(ACC) ← (ACC) + (tmp)
Description
Adds a 40-bit operand to the 40-bit ACC register contents and stores the result in the
ACC register. The 40-bit operand is a sign-extended result of the concatenation of the
two source operands op1 (LSW) and op2 (MSW). The 40-bit operand is then multiplied
by two before being added to ACC register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoADD2
CoADD2
CoADD2
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 42 rrr0:0000
83 nm 42 rrr0:0qqq
93 Xm 42 rrr0:0qqq
8-319
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoASHR
Accumulator Arithmetic Shift Right with Round
Group
Shift Instructions
Syntax
CoASHR op1, rnd
Source Operand(s)
op1 → shift counter
Destination Operand(s)
ACC → 40-bit signed value
CoASHR
Operation
(count) ← (op1)
(C) ← 0
DO WHILE (count) ≠ 0
(ACC[n]) ← (ACC[n+1]) [n=0...38]
(count) ← (count) -1
END WHILE
(ACC) ← (ACC) + 0000 8000h
(MAL) ← 0
Description
Arithmetically shifts the ACC register right by the number of times as specified by the
operand op1. Then, the result is 2s complement rounded before being stored in the
40-bit ACC register. To preserve the sign of the ACC register, the most significant bits
of the result are filled with sign 0 if the original most significant bit was a 0 or with sign 1
if the original most significant bit was 1. Only shift values from 0 to 16 (inclusive) are
allowed. op1 can be either a 5-bit unsigned immediate data (the shift range is from 0 to
16 in this case) or the four least significant bits (the shift range is from 0 to 15 in that
case) of any register directly or indirectly addressed operand.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
MSL
Set if an arithmetic overflow occurred. Cleared otherwise.
Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated when rounding. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-320
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoASHR
CoASHR
CoASHR
User Manual
#data5 , rnd
Rwn , rnd
[Rwm*] , rnd
Format
A3 00 B2 rrr#:#
A3 nn BA rrr0:0000
83 mm BA rrr0:0qqq
8-321
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoASHR
CoASHR
Accumulator Arithmetic Shift Right
Group
Shift Instructions
Syntax
CoASHR op1
Source Operand(s)
op1 → shift counter
Destination Operand(s)
ACC → 40-bit signed value
Operation
(count) ← (op1)
(C) ← 0
DO WHILE (count) ≠ 0
(ACC[n]) ← (ACC[n+1]) [n=0...38]
(count) ← (count) -1
END WHILE
Description
Arithmetically shifts the ACC register right by the number of times as specified by the
operand op1. To preserve the sign of the ACC register, the most significant bits of the
result are filled with sign 0 if the original most significant bit was a 0 or with sign 1 if the
original most significant bit was 1. Only shift values from 0 to 16 (inclusive) are allowed.
op1 can be either a 5-bit unsigned immediate data (the shift range is from 0 to 16 in this
case) or the four least significant bits (the shift range is from 0 to 15 in that case) of any
register directly or indirectly addressed operand. The MS bit of the MCW register does
not affect the result.
MAC Flags
MV
0
MSL
MV
MSL
ME
MSV
MC
MZ
MN
User Manual
ME
*
MSV
-
MC
0
MZ
*
MN
*
Sat.
no
Always cleared.
Not affected.
Set if the MAE is used. Cleared otherwise.
Not affected.
Always cleared.
Set if result equals zero. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
8-322
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoASHR
CoASHR
CoASHR
User Manual
#data5
Rwn
[Rwm*]
Format
A3 00 A2 rrr#:#
A3 nn AA rrr0:0000
83 mm AA rrr0:0qqq
8-323
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoCMP
CoCMP
Compare
Group
Compare Instructions
Syntax
CoCMP op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
none
Operation
tmp ← (op2) || (op1)
(ACC) ⇔ (tmp)
Description
Subtracts a 40-bit signed operand from the 40-bit ACC contents and updates the N, Z
and C flags of the MSW register leaving the ACC register unchanged. The 40-bit
operand is a sign-extended result of the concatenation of the two source operands op1
(LSW) and op2 (MSW). The MS bit of the MCW register does not affect the result.
MAC Flags
MV
*
MSL
-
ME
-
MSV
-
MC
*
MZ
*
MN
*
Sat.
no
MV
Set if the ACC contents are strictly less than the 40-bit operand. Cleared
otherwise.
MSL Not affected.
ME
Not affected.
MSV Not affected.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoCMP
CoCMP
CoCMP
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm C2 rrr0:0000
83 nm C2 rrr0:0qqq
93 Xm C2 rrr0:0qqq
8-324
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoLOAD
CoLOAD
Load Accumulator
Group
Arithmetic Instructions
Syntax
CoLOAD op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op2) || (op1)
(ACC) ← 0 + (tmp)
Description
Loads the 40-bit ACC register with a 40-bit source operand. The 40-bit source operand
is the sign-extended result of the concatenation of the two source operands op1 (LSW)
and op2 (MSW).
MAC Flags
MV
0
MSL
MV
MSL
ME
MSV
MC
MZ
MN
ME
0
MSV
-
MC
0
MZ
*
MN
*
Sat.
no
Always cleared.
Not affected.
Always cleared.
Not affected.
Always cleared.
Set if result equals zero. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoLOAD
CoLOAD
CoLOAD
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 22 rrr0:0000
83 nm 22 rrr0:0qqq
93 Xm 22 rrr0:0qqq
8-325
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoLOAD-
CoLOAD-
Load Accumulator
Group
Arithmetic Instructions
Syntax
CoLOAD- op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op2) || (op1)
(ACC) ← 0 - (tmp)
Description
Loads the 40-bit ACC register with a 40-bit source operand. The 40-bit source operand
is a sign-extended result of the concatenation of the two source operands op1 (LSW)
and op2 (MSW). The 40-bit source operand is 2s complemented, before being stored in
the ACC register.
MAC Flags
MV
0
MSL
*
ME
*
MSV
-
MC
*
MZ
*
MN
*
Sat.
yes
MV
MSL
Always cleared.
Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Not affected.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoLOADCoLOADCoLOAD-
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 2A rrr0:0000
83 nm 2A rrr0:0qqq
93 Xm 2A rrr0:0qqq
8-326
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoLOAD2
CoLOAD2
Load Accumulator
Group
Arithmetic Instructions
Syntax
CoLOAD2 op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← 2 * ((op2) || (op1) )
(ACC) ← 0 + (tmp)
Description
Loads the 40-bit ACC register with a 40-bit source operand. The 40-bit source operand
is a sign-extended results of the concatenation of the two source operands op1 (LSW)
and op2 (MSW). The 40-bit operand is also multiplied by two, before being stored in the
ACC register.
MAC Flags
MV
0
MSL
*
ME
*
MSV
-
MC
0
MZ
*
MN
*
Sat.
yes
MV
MSL
Always cleared.
Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Not affected.
MC
Always cleared.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoLOAD2
CoLOAD2
CoLOAD2
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 62 rrr0:0000
83 nm 62 rrr0:0qqq
93 Xm 62 rrr0:0qqq
8-327
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoLOAD2-
CoLOAD2-
Load Accumulator
Group
Arithmetic Instructions
Syntax
CoLOAD2- op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← 2 * ((op2) || (op1) )
(ACC) ← 0 - (tmp)
Description
Loads the 40-bit ACC register with a 40-bit source operand. The 40-bit source operand
is a sign-extended result of the concatenation of the two source operands op1 (LSW)
and op2 (MSW). The 40-bit operand is also multiplied by two and negated, before being
stored in the ACC register.
MAC Flags
MV
0
MSL
*
ME
*
MSV
-
MC
*
MZ
*
MN
*
Sat.
yes
MV
MSL
Always cleared.
Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Not affected.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoLOAD2CoLOAD2CoLOAD2-
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 6A rrr0:0000
83 nm 6A rrr0:0qqq
93 Xm 6A rrr0:0qqq
8-328
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMAC
CoMAC
Multiply-Accumulate with Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMAC op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
IF (MP = 1) THEN
(tmp) ← ((op1) * (op2)) <<1
(ACC) ← (ACC) + (tmp) + 00 0000 8000h
ELSE
(tmp) ← (op1) * (op2)
(ACC) ← (ACC) + (tmp) + 00 0000 8000h
END IF
(MAL) ← 0
Description
Multiplies the two signed 16-bit source operands op1 and op2. The resulting signed
32-bit product is first sign-extended; then, if the MP flag is set, it is one-bit left shifted;
then, it is added to the 40-bit ACC register contents. Finally, the result is 2s complement
rounded before being stored in the 40-bit ACC register. The MAL register is cleared.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-329
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMAC
CoMAC
CoMAC
User Manual
Rwn , Rwm , rnd
Rwn , [Rwm*] , rnd
[IDXi*] , [Rwm*] , rnd
Format
A3 nm D1 rrr0:0000
83 nm D1 rrr0:0qqq
93 Xm D1 rrr0:0qqq
8-330
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMAC
CoMAC
Multiply-Accumulate
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMAC op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
IF (MP = 1) THEN
(tmp) ← ((op1) * (op2)) <<1
(ACC) ← (ACC) + (tmp)
ELSE
(tmp) ← (op1) * (op2)
(ACC) ← (ACC) + (tmp)
END IF
Description
Multiplies the two signed 16-bit source operands op1 and op2. The resulting signed
32-bit product is first sign-extended; then, if the MP flag is set, it is one-bit left shifted;
then, it is added to the 40-bit ACC register contents before being stored in the 40-bit
ACC register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-331
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMAC
CoMAC
CoMAC
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm D0 rrr0:0000
83 nm D0 rrr0:0qqq
93 Xm D0 rrr0:0qqq
8-332
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMAC-
CoMAC-
Multiply-Accumulate
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMAC- op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
IF (MP = 1) THEN
(tmp) ← ((op1) * (op2)) <<1
(ACC) ← (ACC) - (tmp)
ELSE
(tmp) ← (op1) * (op2)
(ACC) ← (ACC) - (tmp)
END IF
Description
Multiplies the two signed 16-bit source operands op1 and op2. The resulting signed
32-bit product is first sign-extended; then, if the MP flag is set, it is one-bit left shifted;
then, it is subtracted from the 40-bit ACC register contents before being stored in the
40-bit ACC register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-333
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMACCoMACCoMAC-
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm E0 rrr0:0000
83 nm E0 rrr0:0qqq
93 Xm E0 rrr0:0qqq
8-334
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACM
CoMACM
Multiply-Accumulate & Move & Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACM op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
IF (MP = 1) THEN
(tmp) ← (((op1)) * ((op2))) <<1
(ACC) ← (ACC) + (tmp) + 00 0000 8000h
ELSE
(tmp) ← ((op1))*((op2))
(ACC) ← (ACC) + (tmp) + 00 0000 8000h
END IF
(MAL) ← 0
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two signed 16-bit source operands op1 and op2. The resulting signed
32-bit product is first sign-extended; then, if the MP flag is set, it is one-bit left shifted;
and next, it is added to the 40-bit ACC register contents. Finally, the result is 2s
complement rounded before being stored in the 40-bit ACC register. The MAL register
is cleared. In parallel to the arithmetic operation and to the two parallel reads, the data
pointed to by IDXi overwrites another data located in memory (DPRAM). The address
of the overwritten data depends on the operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
User Manual
8-335
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACM
User Manual
[IDXi*], [Rwm*] , rnd
Format
93 Xm D9 rrr0:0qqq
8-336
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACM
CoMACM
Multiply-Accumulate & Move
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACM op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
IF (MP = 1) THEN
(tmp) ← (((op1)) * ((op2))) <<1
(ACC) ← (ACC) + (tmp)
ELSE
(tmp) ← ((op1)) * ((op2))
(ACC) ← (ACC) + (tmp)
END IF
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two signed 16-bit source operands op1 and op2. The resulting signed
32-bit product is first sign-extended; then if the MP flag is set, it is one-bit left shifted;
and next it is added to the 40-bit ACC register contents before being stored in the 40-bit
ACC register. In parallel to the arithmetic operation and to the two parallel reads, the
data pointed to by IDXi overwrites another data located in memory (DPRAM). The
address of the overwritten data depends on the operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-337
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMACM
User Manual
[IDXi*], [Rwm*]
Format
93 Xm D8 rrr0:0qqq
8-338
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACM-
CoMACM-
Multiply-Accumulate & Move
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACM- op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
IF (MP = 1) THEN
(tmp) ← (((op1)) * ((op2))) <<1
(ACC) ← (ACC) - (tmp)
ELSE
(tmp) ← ((op1)) * ((op2))
(ACC) ← (ACC) - (tmp)
END IF
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two signed 16-bit source operands op1 and op2. The resulting signed
32-bit product is first sign-extended; then, if the MP flag is set, it is one-bit left shifted;
and next, it is subtracted from the 40-bit ACC register contents before being stored in
the 40-bit ACC register. In parallel to the arithmetic operation and to the two parallel
reads, the data pointed to by IDXi overwrites another data located in memory
(DPRAM). The address of the overwritten data depends on the operation executed on
IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-339
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMACM-
User Manual
[IDXi*], [Rwm*]
Format
93 Xm E8 rrr0:0qqq
8-340
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMR
CoMACMR
Multiply-Accumulate & Move & Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMR op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
IF (MP = 1) THEN
(tmp) ← (((op1)) * ((op2))) <<1
(ACC) ← (tmp) - (ACC) + 00 0000 8000h
ELSE
(tmp) ← ((op1))*((op2))
(ACC) ← (tmp) - (ACC) + 00 0000 8000h
END IF
(MAL) ← 0
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two signed 16-bit source operands op1 and op2. The resulting signed
32-bit product is first sign-extended; then, if the MP flag is set, it is one-bit left shifted;
and next, the 40-bit ACC register contents are subtracted from the result Finally, the
result is 2s complement rounded before being stored in the 40-bit ACC register. The
MAL register is cleared. In parallel to the arithmetic operation and to the two parallel
reads, the data pointed to by IDXi overwrites another data located in memory
(DPRAM). The address of the overwritten data depends on the operation executed on
IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
User Manual
8-341
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
MZ
MN
Set if result equals zero. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACMR
User Manual
[IDXi*], [Rwm*] , rnd
Format
93 Xm F9 rrr0:0qqq
8-342
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMR
CoMACMR
Multiply-Accumulate & Move
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMR op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
IF (MP = 1) THEN
(tmp) ← (((op1)) * ((op2))) <<1
(ACC) ← (tmp) - (ACC)
ELSE
(tmp) ← ((op1)) * ((op2))
(ACC) ← (tmp) - (ACC)
END IF
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two signed 16-bit source operands op1 and op2. The resulting signed
32-bit product is first sign-extended; then, if the MP flag is set, it is one-bit left shifted;
and next, the 40-bit ACC register contents are subtracted from the result before being
stored in the 40-bit ACC register. In parallel to the arithmetic operation and to the two
parallel reads, the data pointed to by IDXi overwrites another data located in memory
(DPRAM). The address of the overwritten data depends on the operation executed on
IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-343
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMACMR
User Manual
[IDXi*], [Rwm*]
Format
93 Xm F8 rrr0:0qqq
8-344
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMRsu
Multiply-Accumulate & Move & Round
CoMACMRsu
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMRsu op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← ((op1)) * ((op2))
(ACC) ← (tmp) - (ACC) + 00 0000 8000h
(MAL) ← 0
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two signed and unsigned 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended; then, the 40-bit
ACC register contents are subtracted from the result before being stored in the 40-bit
ACC register. Finally, the result is 2s complement rounded before being stored in the
40-bit ACC register. The MAL register is cleared. In parallel to the arithmetic operation
and to the two parallel reads, the data pointed to by IDXi overwrites another data
located in memory (DPRAM). The address of the overwritten data depends on the
operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-345
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMACMRsu [IDXi*], [Rwm*] , rnd
User Manual
Format
93 Xm 79 rrr0:0qqq
8-346
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMRsu
Multiply-Accumulate & Move
CoMACMRsu
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMRsu op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← ((op1)) * ((op2))
(ACC) ← (tmp) - (ACC)
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two signed and unsigned 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended; then, the 40-bit
ACC register contents are subtracted from the result before being stored in the 40-bit
ACC register. In parallel to the arithmetic operation and to the two parallel reads, the
data pointed to by IDXi overwrites another data located in memory (DPRAM). The
address of the overwritten data depends on the operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACMRsu [IDXi*], [Rwm*]
User Manual
Format
93 Xm 78 rrr0:0qqq
8-347
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMRu
CoMACMRu
Multiply-Accumulate & Move & Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMRu op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← ((op1))*((op2))
(ACC) ← (tmp) - (ACC) + 00 0000 8000h
(MAL) ← 0
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two unsigned 16-bit source operands op1 and op2. The resulting
unsigned 32-bit product is first zero-extended; then, the 40-bit ACC register contents
are subtracted from the result. Finally, the result is 2s complement rounded before
being stored in the 40-bit ACC register. The MAL register is cleared. In parallel to the
arithmetic operation and to the two parallel reads, the data pointed to by IDXi overwrites
another data located in memory (DPRAM). The address of the overwritten data
depends on the operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-348
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMACMRu
User Manual
[IDXi*], [Rwm*] , rnd
Format
93 Xm 39 rrr0:0qqq
8-349
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMRu
CoMACMRu
Multiply-Accumulate & Move
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMRu op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← ((op1))*((op2))
(ACC) ← (tmp) - (ACC)
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two unsigned 16-bit source operands op1 and op2. The resulting
unsigned 32-bit product is first zero-extended; then, the 40-bit ACC register contents
are subtracted from the result before being stored in the 40-bit ACC register. In parallel
to the arithmetic operation and to the two parallel reads, the data pointed to by IDXi
overwrites another data located in memory (DPRAM). The address of the overwritten
data depends on the operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACMRu
User Manual
[IDXi*], [Rwm*]
Format
93 Xm 38 rrr0:0qqq
8-350
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMRus
Multiply-Accumulate & Move & Round
CoMACMRus
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMRus op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← ((op1)) * ((op2))
(ACC) ← (tmp) - (ACC) + 00 0000 8000h
(MAL) ← 0
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two unsigned and signed 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended; then, the 40-bit
ACC register contents are subtracted from the result. Finally, the result is 2s
complement rounded before being stored in the 40-bit ACC register. The MAL register
is cleared. In parallel to the arithmetic operation and to the two parallel reads, the data
pointed to by IDXi overwrites another data located in memory (DPRAM). The address
of the overwritten data depends on the operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-351
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMACMRus [IDXi*], [Rwm*] , rnd
User Manual
Format
93 Xm B9 rrr0:0qqq
8-352
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMRus
Multiply-Accumulate & Move
CoMACMRus
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMRus op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← ((op1)) * ((op2))
(ACC) ← (tmp) - (ACC)
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two unsigned and signed 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended; then, the 40-bit
ACC register contents are subtracted from the result before being stored in the 40-bit
ACC register. In parallel to the arithmetic operation and to the two parallel reads, the
data pointed to by IDXi overwrites another data located in memory (DPRAM). The
address of the overwritten data depends on the operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACMRus [IDXi*], [Rwm*]
User Manual
Format
93 Xm B8 rrr0:0qqq
8-353
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMsu
CoMACMsu
Multiply-Accumulate & Move & Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMsu op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← ((op1)) * ((op2))
(ACC) ← (ACC) + (tmp) + 00 0000 8000h
(MAL) ← 0
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two signed and unsigned 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended; then, it is added
to the 40-bit ACC register contents. Finally, the result is 2s complement rounded before
being stored in the 40-bit ACC register. The MAL register is cleared. In parallel to the
arithmetic operation and to the two parallel reads, the data pointed to by IDXi overwrites
another data located in memory (DPRAM). The address of the overwritten data
depends on the operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-354
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMACMsu
User Manual
[IDXi*], [Rwm*] , rnd
Format
93 Xm 59 rrr0:0qqq
8-355
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMsu
CoMACMsu
Multiply-Accumulate & Move
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMsu op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← ((op1)) * ((op2))
(ACC) ← (ACC) + (tmp)
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two signed and unsigned 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended; then, it is added
to the 40-bit ACC register contents before being stored in the 40-bit ACC register. In
parallel to the arithmetic operation and to the two parallel reads, the data pointed to by
IDXi overwrites another data located in memory (DPRAM). The address of the
overwritten data depends on the operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACMsu
User Manual
[IDXi*], [Rwm*]
Format
93 Xm 58 rrr0:0qqq
8-356
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMsu-
CoMACMsu-
Multiply-Accumulate & Move
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMsu- op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← ((op1)) * ((op2))
(ACC) ← (ACC) - (tmp)
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two signed and unsigned 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended; then, it is
subtracted from the 40-bit ACC register contents before being stored in the 40-bit ACC
register. In parallel to the arithmetic operation and to the two parallel reads, the data
pointed to by IDXi overwrites another data located in memory (DPRAM). The address
of the overwritten data depends on the operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACMsu-
User Manual
[IDXi*], [Rwm*]
Format
93 Xm 68 rrr0:0qqq
8-357
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMu
CoMACMu
Multiply-Accumulate & Move & Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMu op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← ((op1))*((op2))
(ACC) ← (ACC) + (tmp) + 00 0000 8000h
(MAL) ← 0
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two unsigned 16-bit source operands op1 and op2. The resulting
unsigned 32-bit product is first zero-extended; then, it is added to the 40-bit ACC
register contents. Finally, the result is 2s complement rounded before being stored in
the 40-bit ACC register. The MAL register is cleared. In parallel to the arithmetic
operation and to the two parallel reads, the data pointed to by IDXi overwrites another
data located in memory (DPRAM). The address of the overwritten data depends on the
operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-358
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMACMu
User Manual
[IDXi*], [Rwm*] , rnd
Format
93 Xm 19 rrr0:0qqq
8-359
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMu
CoMACMu
Multiply-Accumulate & Move
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMu op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← ((op1))*((op2))
(ACC) ← (ACC) + (tmp)
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two unsigned 16-bit source operands op1 and op2. The resulting
unsigned 32-bit product is first zero-extended; then, it is added to the 40-bit ACC
register contents before being stored in the 40-bit ACC register. In parallel to the
arithmetic operation and to the two parallel reads, the data pointed to by IDXi overwrites
another data located in memory (DPRAM). The address of the overwritten data
depends on the operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACMu
User Manual
[IDXi*], [Rwm*]
Format
93 Xm 18 rrr0:0qqq
8-360
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMu-
CoMACMu-
Multiply-Accumulate & Move
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMu- op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← ((op1))*((op2))
(ACC) ← (ACC) - (tmp)
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two unsigned 16-bit source operands op1 and op2. The resulting
unsigned 32-bit product is first zero-extended; then, it is subtracted from the 40-bit ACC
register contents before being stored in the 40-bit ACC register. In parallel to the
arithmetic operation and to the two parallel reads, the data pointed to by IDXi overwrites
another data located in memory (DPRAM). The address of the overwritten data
depends on the operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACMu-
User Manual
[IDXi*], [Rwm*]
Format
93 Xm 28 rrr0:0qqq
8-361
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMus
CoMACMus
Multiply-Accumulate & Move & Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMus op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← ((op1)) * ((op2))
(ACC) ← (ACC) + (tmp) + 00 0000 8000h
(MAL) ← 0
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two unsigned and signed 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended; then, it is added
to the 40-bit ACC register contents. Finally, the result is 2s complement rounded before
being stored in the 40-bit ACC register. In parallel to the arithmetic operation and to the
two parallel reads, the data pointed to by IDXi overwrites another data located in
memory (DPRAM). The address of the overwritten data depends on the operation
executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-362
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMACMus
User Manual
[IDXi*], [Rwm*] , rnd
Format
93 Xm 99 rrr0:0qqq
8-363
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMus
CoMACMus
Multiply-Accumulate & Move
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMus op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← ((op1)) * ((op2))
(ACC) ← (ACC) + (tmp)
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two unsigned and signed 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended; then, it is added
to the 40-bit ACC register contents before being stored in the 40-bit ACC register. In
parallel to the arithmetic operation and to the two parallel reads, the data pointed to by
IDXi overwrites another data located in memory (DPRAM). The address of the
overwritten data depends on the operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACMus
User Manual
[IDXi*], [Rwm*]
Format
93 Xm 98 rrr0:0qqq
8-364
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACMus-
CoMACMus-
Multiply-Accumulate & Move
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACMus- op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← ((op1)) * ((op2))
(ACC) ← (ACC) - (tmp)
((IDXi(-*))) ← ((IDXi))
Description
Multiplies the two unsigned and signed 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended; then, it is
subtracted from the 40-bit ACC register contents before being stored in the 40-bit ACC
register. In parallel to the arithmetic operation and to the two parallel reads, the data
pointed to by IDXi overwrites another data located in memory (DPRAM). The address
of the overwritten data depends on the operation executed on IDXi.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACMus-
User Manual
[IDXi*], [Rwm*]
Format
93 Xm A8 rrr0:0qqq
8-365
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACR
CoMACR
Multiply-Accumulate & Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACR op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
IF (MP = 1) THEN
(tmp) ← ((op1) * (op2)) <<1
(ACC) ← (tmp) - (ACC) + 00 0000 8000h
ELSE
(tmp) ← (op1) * (op2)
(ACC) ← (tmp) - (ACC) + 00 0000 8000h
END IF
(MAL) ← 0
Description
Multiplies the two signed 16-bit source operands op1 and op2. The resulting signed
32-bit product is first sign-extended; then, if the MP flag is set, it is one-bit left shifted;
then, the 40-bit ACC register contents are subtracted from the result. Finally, the result
is 2s complement rounded before being stored in the 40-bit ACC register. The MAL
register is cleared.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-366
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMACR
CoMACR
CoMACR
User Manual
Rwn , Rwm , rnd
Rwn , [Rwm*] , rnd
[IDXi*] , [Rwm*] , rnd
Format
A3 nm F1 rrr0:0000
83 nm F1 rrr0:0qqq
93 Xm F1 rrr0:0qqq
8-367
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACR
CoMACR
Multiply-Accumulate
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACR op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
IF (MP = 1) THEN
(tmp) ← ((op1) * (op2)) <<1
(ACC) ← (tmp) - (ACC)
ELSE
(tmp) ← (op1) * (op2)
(ACC) ← (tmp) - (ACC)
END IF
Description
Multiplies the two signed 16-bit source operands op1 and op2. The resulting signed
32-bit product is first sign-extended; then, if the MP flag is set, it is one-bit left shifted;
then, the 40-bit ACC register contents are subtracted from the result before being
stored in the 40-bit ACC register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-368
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMACR
CoMACR
CoMACR
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm F0 rrr0:0000
83 nm F0 rrr0:0qqq
93 Xm F0 rrr0:0qqq
8-369
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACRsu
CoMACRsu
Mixed Multiply-Accumulate & Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACRsu op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op1) * (op2)
(ACC) ← (tmp) - (ACC) + 00 0000 8000h
(MAL) ← 0
Description
Multiplies the two signed and unsigned 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended and then the
40-bit ACC register contents are subtracted from the result. Finally, the result is 2s
complement rounded before being stored in the 40-bit ACC register. The MAL register
is cleared.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-370
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMACRsu
CoMACRsu
CoMACRsu
User Manual
Rwn , Rwm , rnd
Rwn , [Rwm*] , rnd
[IDXi*] , [Rwm*] , rnd
Format
A3 nm 71 rrr0:0000
83 nm 71 rrr0:0qqq
93 Xm 71 rrr0:0qqq
8-371
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACRsu
CoMACRsu
Mixed Multiply-Accumulate
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACRsu op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op1) * (op2)
(ACC) ← (tmp) - (ACC)
Description
Multiplies the two signed and unsigned 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended and then the
40-bit ACC register contents are subtracted from the result before being stored in the
40-bit ACC register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACRsu
CoMACRsu
CoMACRsu
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 70 rrr0:0000
83 nm 70 rrr0:0qqq
93 Xm 70 rrr0:0qqq
8-372
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACRu
Unsigned Multiply-Accumulate & Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACRu op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
CoMACRu
Operation
(tmp) ← (op1) * (op2)
(ACC) ← (tmp) - (ACC) + 00 0000 8000h
(MAL) ← 0
Description
Multiplies the two unsigned 16-bit source operands op1 and op2. The resulting
unsigned 32-bit product is first zero-extended and then the 40-bit ACC register contents
are subtracted from the result. Finally, the result is 2s complement rounded before
being stored in the 40-bit ACC register. The MAL register is cleared.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACRu
CoMACRu
CoMACRu
User Manual
Rwn , Rwm , rnd
Rwn , [Rwm*] , rnd
[IDXi*] , [Rwm*] , rnd
Format
A3 nm 31 rrr0:0000
83 nm 31 rrr0:0qqq
93 Xm 31 rrr0:0qqq
8-373
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACRu
CoMACRu
Unsigned Multiply-Accumulate
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACRu op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op1) * (op2)
(ACC) ← (tmp) - (ACC)
Description
Multiplies the two unsigned 16-bit source operands op1 and op2. The resulting
unsigned 32-bit product is first zero-extended and then the 40-bit ACC register contents
are subtracted from the result before being stored in the 40-bit ACC register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACRu
CoMACRu
CoMACRu
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 30 rrr0:0000
83 nm 30 rrr0:0qqq
93 Xm 30 rrr0:0qqq
8-374
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACRus
CoMACRus
Mixed Multiply-Accumulate & Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACRus op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op1) * (op2)
(ACC) ← (tmp) - (ACC) + 00 0000 8000h
(MAL) ← 0
Description
Multiplies the two unsigned and signed 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended and then the
40-bit ACC register contents are subtracted from the result. Finally, the result is 2s
complement rounded before being stored in the 40-bit ACC register. The MAL register
is cleared.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-375
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMACRus
CoMACRus
CoMACRus
User Manual
Rwn , Rwm , rnd
Rwn , [Rwm*] , rnd
[IDXi*] , [Rwm*] , rnd
Format
A3 nm B1 rrr0:0000
83 nm B1 rrr0:0qqq
93 Xm B1 rrr0:0qqq
8-376
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACRus
CoMACRus
Mixed Multiply-Accumulate
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACRus op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op1) * (op2)
(ACC) ← (tmp) - (ACC)
Description
Multiplies the two unsigned and signed 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended and then the
40-bit ACC register contents are subtracted from the result before being stored in the
40-bit ACC register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACRus
CoMACRus
CoMACRus
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm B0 rrr0:0000
83 nm B0 rrr0:0qqq
93 Xm B0 rrr0:0qqq
8-377
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACsu
CoMACsu
Mixed Multiply-Accumulate & Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACsu op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op1) * (op2)
(ACC) ← (ACC) + (tmp) + 00 0000 8000h
(MAL) ← 0
Description
Multiplies the two signed and unsigned 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended and then added
to the 40-bit ACC register contents. Finally, the result is 2s complement rounded before
being stored in the 40-bit ACC register. The MAL register is cleared.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACsu
CoMACsu
CoMACsu
User Manual
Rwn , Rwm , rnd
Rwn , [Rwm*] , rnd
[IDXi*] , [Rwm*] , rnd
Format
A3 nm 51 rrr0:0000
83 nm 51 rrr0:0qqq
93 Xm 51 rrr0:0qqq
8-378
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACsu
CoMACsu
Mixed Multiply-Accumulate
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACsu op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op1) * (op2)
(ACC) ← (ACC) + (tmp)
Description
Multiplies the two signed and unsigned 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended and then added
to the 40-bit ACC register contents before being stored in the 40-bit ACC register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACsu
CoMACsu
CoMACsu
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 50 rrr0:0000
83 nm 50 rrr0:0qqq
93 Xm 50 rrr0:0qqq
8-379
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACsu-
CoMACsu-
Mixed Multiply-Accumulate
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACsu- op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op1) * (op2)
(ACC) ← (ACC) - (tmp)
Description
Multiplies the two signed and unsigned 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended and then
subtracted from the 40-bit ACC register contents before being stored in the 40-bit ACC
register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACsuCoMACsuCoMACsu-
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 60 rrr0:0000
83 nm 60 rrr0:0qqq
93 Xm 60 rrr0:0qqq
8-380
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACu
Unsigned Multiply-Accumulate & Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACu op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
CoMACu
Operation
(tmp) ← (op1) * (op2)
(ACC) ← (ACC) + (tmp) + 00 0000 8000h
(MAL) ← 0
Description
Multiplies the two unsigned 16-bit source operands op1 and op2. The resulting
unsigned 32-bit product is first zero-extended and then added to the 40-bit ACC register
contents. Finally, the result is 2s complement rounded before being stored in the 40-bit
ACC register. The MAL register is cleared.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACu
CoMACu
CoMACu
User Manual
Rwn , Rwm , rnd
Rwn , [Rwm*] , rnd
[IDXi*] , [Rwm*] , rnd
Format
A3 nm 11 rrr0:0000
83 nm 11 rrr0:0qqq
93 Xm 11 rrr0:0qqq
8-381
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACu
CoMACu
Unsigned Multiply-Accumulate
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACu op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op1) * (op2)
(ACC) ← (ACC) + (tmp)
Description
Multiplies the two unsigned 16-bit source operands op1 and op2. The resulting
unsigned 32-bit product is first zero-extended and then added to the 40-bit ACC register
contents before being stored in the 40-bit ACC register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACu
CoMACu
CoMACu
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 10 rrr0:0000
83 nm 10 rrr0:0qqq
93 Xm 10 rrr0:0qqq
8-382
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACu-
CoMACu-
Unsigned Multiply-Accumulate
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACu- op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op1) * (op2)
(ACC) ← (ACC) - (tmp)
Description
Multiplies the two unsigned 16-bit source operands op1 and op2. The resulting
unsigned 32-bit product is first zero-extended and then subtracted from the 40-bit ACC
register contents before being stored in the 40-bit ACC register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACuCoMACuCoMACu-
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 20 rrr0:0000
83 nm 20 rrr0:0qqq
93 Xm 20 rrr0:0qqq
8-383
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACus
Mixed Multiply-Accumulate with Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACus op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
CoMACus
Operation
(tmp) ← (op1) * (op2)
(ACC) ← (ACC) + (tmp) + 00 0000 8000h
(MAL) ← 0
Description
Multiplies the two unsigned and signed 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended and then added
to the 40-bit ACC register contents. Finally, the result is 2s complement rounded before
being stored in the 40-bit ACC register. The MAL register is cleared.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACus
CoMACus
CoMACus
User Manual
Rwn , Rwm , rnd
Rwn , [Rwm*] , rnd
[IDXi*] , [Rwm*] , rnd
Format
A3 nm 91 rrr0:0000
83 nm 91 rrr0:0qqq
93 Xm 91 rrr0:0qqq
8-384
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACus
CoMACus
Mixed Multiply-Accumulate
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACus op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op1) * (op2)
(ACC) ← (ACC) + (tmp)
Description
Multiplies the two unsigned and signed 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended and then added
to the 40-bit ACC register contents before being stored in the 40-bit ACC register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACus
CoMACus
CoMACus
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 90 rrr0:0000
83 nm 90 rrr0:0qqq
93 Xm 90 rrr0:0qqq
8-385
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMACus-
CoMACus-
Mixed Multiply-Accumulate
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMACus- op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op1) * (op2)
(ACC) ← (ACC) - (tmp)
Description
Multiplies the two unsigned and signed 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended and then
subtracted from the 40-bit ACC register contents before being stored in the 40-bit ACC
register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMACusCoMACusCoMACus-
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm A0 rrr0:0000
83 nm A0 rrr0:0qqq
93 Xm A0 rrr0:0qqq
8-386
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMAX
CoMAX
Maximum
Group
Compare Instructions
Syntax
CoMAX op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op2) || (op1)
(ACC) ← max((ACC),(tmp))
Description
Compares a signed 40-bit operand against the 40-bit ACC register contents. The 40-bit
operand is a sign-extended result of the concatenation of the two source operands op1
(LSW) and op2 (MSW) which is then sign-extended. If the contents of the 40-bit ACC
register are smaller than the 40-bit operand, then the ACC register is loaded with it.
Otherwise, the ACC register remains unchanged. The MS bit of the MCW register does
not affect the result.
MAC Flags
MV
0
MSL
*
MV
MSL
ME
MSV
MC
MZ
MN
ME
*
MSV
-
MC
0
MZ
*
MN
*
Sat.
no
Always cleared.
Set if the contents of ACC is changed. Not affected otherwise.
Set if the MAE is used. Cleared otherwise.
Not affected.
Always cleared.
Set if result equals zero. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMAX
CoMAX
CoMAX
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 3A rrr0:0000
83 nm 3A rrr0:0qqq
93 Xm 3A rrr0:0qqq
8-387
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMIN
CoMIN
Minimum
Group
Compare Instructions
Syntax
CoMIN op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op2) || (op1)
(ACC) ← min((ACC),(tmp))
Description
Compares a signed 40-bit operand against the 40-bit ACC register contents. The 40-bit
operand is a sign-extended result of the concatenation of the two source operands op1
(LSW) and op2 (MSW). If the contents of the ACC register are greater than the 40-bit
operand, then the ACC register is loaded with it. Otherwise, the ACC register remains
unchanged. The MS bit of the MCW register does not affect the result.
MAC Flags
MV
0
MSL
*
MV
MSL
ME
MSV
MC
MZ
MN
ME
*
MSV
-
MC
0
MZ
*
MN
*
Sat.
no
Always cleared.
Set if the contents of ACC is changed. Not affected otherwise.
Set if the MAE is used. Cleared otherwise.
Not affected.
Always cleared.
Set if result equals zero. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMIN
CoMIN
CoMIN
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 7A rrr0:0000
83 nm 7A rrr0:0qqq
93 Xm 7A rrr0:0qqq
8-388
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMOV
CoMOV
Memory to Memory Move
Group
Data Movement Instructions
Syntax
CoMOV op1, op2
Source Operand(s)
op2 → WORD
Destination Operand(s)
op1 → WORD
Operation
(op1) ← (op2)
Description
Moves the contents of the memory location specified by the source operand op2 to the
memory location specified by the destination operand op1. Note that in this case, unlike
for the other instructions, IDXi can address the entire memory. This instruction does not
affect the Mac Flags, but modifies the CPU Flags as any other MOV instruction.
Note: CoMOV is the only MAC instruction which affects the CPU flags. MAC Flags are
not affected.
CPU Flags
E
*
E
Z
V
C
N
Z
*
V
-
C
-
N
*
Set if the value of op2 represents the lowest possible negative number.
Cleared otherwise. Used to signal the end of a table.
Set if the value of the source operand op2 equals zero. Cleared
otherwise.
Not affected.
Not affected.
Set if the most significant bit of the source operand op2 is set. Cleared
otherwise.
Encoding
Mnemonic
CoMOV
User Manual
[IDXi*] , [Rwm*]
Format
D3 Xm 00 rrr0:0qqq
8-389
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMUL
CoMUL
Signed Multiply with Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMUL op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
IF (MP = 1) THEN
(ACC) ← ((op1) * (op2)) <<1 + 00 0000 8000h
ELSE
(ACC) ← (op1) * (op2) + 00 0000 8000h
END IF
(MAL) ← 0
Description
Multiplies the two signed 16-bit source operands op1 and op2. The resulting signed
32-bit product is first sign-extended; then, if the MP flag is set, it is one-bit left shifted.
Finally, the result is 2s complement rounded before being stored in the 40-bit ACC
register. The MAL register is cleared.
MAC Flags
MV
0
MSL
*
ME
*
MSV
-
MC
0
MZ
*
MN
*
Sat.
yes
MV
MSL
Always cleared.
Not affected when MP or MS are cleared, otherwise, only set in case of
8000h by 8000h multiplication.
ME
Set when MP is set and MS is cleared and in case of 8000h by 8000h
multiplication. Cleared otherwise.
MSV Not affected.
MC
Always cleared.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-390
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMUL
CoMUL
CoMUL
User Manual
Rwn , Rwm , rnd
Rwn , [Rwm*] , rnd
[IDXi*] , [Rwm*] , rnd
Format
A3 nm C1 rrr0:0000
83 nm C1 rrr0:0qqq
93 Xm C1 rrr0:0qqq
8-391
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMUL
CoMUL
Signed Multiply
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMUL op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
IF (MP = 1) THEN
(ACC) ← ((op1) * (op2)) <<1
ELSE
(ACC) ← (op1) * (op2)
END IF
Description
Multiplies the two signed 16-bit source operands op1 and op2. The resulting signed
32-bit product is first sign-extended; then, if the MP flag is set, it is one-bit left shifted
before being stored in the 40-bit ACC register.
MAC Flags
MV
0
MSL
*
ME
*
MSV
-
MC
0
MZ
*
MN
*
Sat.
yes
MV
MSL
Always cleared.
Not affected when MP or MS are cleared, otherwise, only set in case of
8000h by 8000h multiplication.
ME
Set when MP is set and MS is cleared and in case of 8000h by 8000h
multiplication. Cleared otherwise.
MSV Not affected.
MC
Always cleared.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
User Manual
8-392
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoMUL
CoMUL
CoMUL
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm C0 rrr0:0000
83 nm C0 rrr0:0qqq
93 Xm C0 rrr0:0qqq
8-393
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMUL-
CoMUL-
Signed Multiply
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMUL- op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
IF (MP = 1) THEN
(ACC) ← - ((op1) * (op2)) <<1
ELSE
(ACC) ← - ((op1) * (op2))
END IF
Description
Multiplies the two signed 16-bit source operands op1 and op2. The resulting signed
32-bit product is first sign-extended; then, if the MP flag is set, it is one-bit left shifted;
and, finally, it is negated before being stored in the 40-bit ACC register.
MAC Flags
MV
0
MSL
0
MV
MSL
ME
MSV
MC
MZ
MN
ME
0
MSV
-
MC
0
MZ
*
MN
*
Sat.
no
Always cleared.
Always cleared.
Always cleared.
Not affected.
Always cleared.
Set if result equals zero. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMULCoMULCoMUL-
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm C8 rrr0:0000
83 nm C8 rrr0:0qqq
93 Xm C8 rrr0:0qqq
8-394
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMULsu
CoMULsu
Mixed Multiply & Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMULsu op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(ACC) ← (op1) * (op2) + 00 0000 8000h
(MAL) ← 0
Description
Multiplies the two signed and unsigned 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended; then, it is
rounded before being stored in the 40-bit ACC register. The MAL register is cleared.
MAC Flags
MV
0
MSL
MV
MSL
ME
MSV
MC
MZ
MN
ME
0
MSV
-
MC
0
MZ
*
MN
*
Sat.
no
Always cleared.
Not affected.
Always cleared.
Not affected.
Always cleared.
Set if result equals zero. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMULsu
CoMULsu
CoMULsu
User Manual
Rwn , Rwm , rnd
Rwn , [Rwm*] , rnd
[IDXi*] , [Rwm*] , rnd
Format
A3 nm 41 rrr0:0000
83 nm 41 rrr0:0qqq
93 Xm 41 rrr0:0qqq
8-395
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMULsu
CoMULsu
Mixed Multiply
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMULsu op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(ACC) ← (op1) * (op2)
Description
Multiplies the two signed and unsigned 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended before being
stored in the 40-bit ACC register.
MAC Flags
MV
0
MSL
MV
MSL
ME
MSV
MC
MZ
MN
ME
0
MSV
-
MC
0
MZ
*
MN
*
Sat.
no
Always cleared.
Not affected.
Always cleared.
Not affected.
Always cleared.
Set if result equals zero. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMULsu
CoMULsu
CoMULsu
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 40 rrr0:0000
83 nm 40 rrr0:0qqq
93 Xm 40 rrr0:0qqq
8-396
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMULsu-
CoMULsu-
Mixed Multiply
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMULsu- op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(ACC) ← - ((op1) * (op2))
Description
Multiplies the two signed and unsigned 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended; then, is negated
before being stored in the 40-bit ACC register.
MAC Flags
MV
0
MSL
MV
MSL
ME
MSV
MC
MZ
MN
ME
0
MSV
-
MC
0
MZ
*
MN
*
Sat.
no
Always cleared.
Not affected.
Always cleared.
Not affected.
Always cleared.
Set if result equals zero. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMULsuCoMULsuCoMULsu-
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 48 rrr0:0000
83 nm 48 rrr0:0qqq
93 Xm 48 rrr0:0qqq
8-397
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMULu
CoMULu
Unsigned Multiply with Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMULu op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(ACC) ← (op1) * (op2) + 00 0000 8000h
(MAL) ← 0
Description
Multiplies the two unsigned 16-bit source operands op1 and op2. The resulting
unsigned 32-bit product is first zero-extended; then, it is rounded before being stored in
the 40-bit ACC register. The MAL register is cleared.
MAC Flags
MV
0
MSL
*
ME
*
MSV
-
MC
0
MZ
*
MN
0
Sat.
yes
MV
MSL
Always cleared.
Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Not affected.
MC
Always cleared.
MZ
Set if result equals zero. Cleared otherwise.
MN
Always cleared.
Encoding
Mnemonic
CoMULu
CoMULu
CoMULu
User Manual
Rwn , Rwm , rnd
Rwn , [Rwm*] , rnd
[IDXi*] , [Rwm*] , rnd
Format
A3 nm 01 rrr0:0000
83 nm 01 rrr0:0qqq
93 Xm 01 rrr0:0qqq
8-398
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMULu
CoMULu
Unsigned Multiply
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMULu op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(ACC) ← (op1) * (op2)
Description
Multiplies the two unsigned 16-bit source operands op1 and op2. The resulting
unsigned 32-bit product is zero-extended before being stored in the 40-bit ACC register.
MAC Flags
MV
0
MSL
*
ME
*
MSV
-
MC
0
MZ
*
MN
0
Sat.
yes
MV
MSL
Always cleared.
Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Not affected.
MC
Always cleared.
MZ
Set if result equals zero. Cleared otherwise.
MN
Always cleared.
Encoding
Mnemonic
CoMULu
CoMULu
CoMULu
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 00 rrr0:0000
83 nm 00 rrr0:0qqq
93 Xm 00 rrr0:0qqq
8-399
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMULu-
CoMULu-
Unsigned Multiply
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMULu- op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(ACC) ← - ((op1) * (op2))
Description
Multiplies the two unsigned 16-bit source operands op1 and op2. The resulting
unsigned 32-bit product is first zero-extended; then, it is negated before being stored in
the 40-bit ACC register.
MAC Flags
MV
0
MSL
*
ME
*
MSV
-
MC
0
MZ
*
MN
*
Sat.
yes
MV
MSL
Always cleared.
Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Not affected.
MC
Always cleared.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMULuCoMULuCoMULu-
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 08 rrr0:0000
83 nm 08 rrr0:0qqq
93 Xm 08 rrr0:0qqq
8-400
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMULus
CoMULus
Mixed Multiply with Round
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMULus op1, op2, rnd
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(ACC) ← (op1) * (op2) + 00 0000 8000h
(MAL) ← 0
Description
Multiplies the two unsigned and signed 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended; then, it is
rounded before being stored in the 40-bit ACC register. The MAL register is cleared.
MAC Flags
MV
0
MSL
MV
MSL
ME
MSV
MC
MZ
MN
ME
0
MSV
-
MC
0
MZ
*
MN
*
Sat.
no
Always cleared.
Not affected.
Always cleared.
Not affected.
Always cleared.
Set if result equals zero. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMULus
CoMULus
CoMULus
User Manual
Rwn , Rwm , rnd
Rwn , [Rwm*] , rnd
[IDXi*] , [Rwm*] , rnd
Format
A3 nm 81 rrr0:0000
83 nm 81 rrr0:0qqq
93 Xm 81 rrr0:0qqq
8-401
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMULus
CoMULus
Mixed Multiply
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMULus op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(ACC) ← (op1) * (op2)
Description
Multiplies the two unsigned and signed 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended before being
stored in the 40-bit ACC register.
MAC Flags
MV
0
MSL
MV
MSL
ME
MSV
MC
MZ
MN
ME
0
MSV
-
MC
0
MZ
*
MN
*
Sat.
no
Always cleared.
Not affected.
Always cleared.
Not affected.
Always cleared.
Set if result equals zero. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMULus
CoMULus
CoMULus
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 80 rrr0:0000
83 nm 80 rrr0:0qqq
93 Xm 80 rrr0:0qqq
8-402
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoMULus-
CoMULus-
Mixed Multiply
Group
Multiply/Multiply-Accumulate Instructions
Syntax
CoMULus- op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(ACC) ← - ((op1) * (op2))
Description
Multiplies the two unsigned and signed 16-bit source operands op1 and op2,
respectively. The resulting signed 32-bit product is first sign-extended; then, it is
negated before being stored in the 40-bit ACC register.
MAC Flags
MV
0
MSL
MV
MSL
ME
MSV
MC
MZ
MN
ME
0
MSV
-
MC
0
MZ
*
MN
*
Sat.
no
Always cleared.
Not affected.
Always cleared.
Not affected.
Always cleared.
Set if result equals zero. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoMULusCoMULusCoMULus-
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 88 rrr0:0000
83 nm 88 rrr0:0qqq
93 Xm 88 rrr0:0qqq
8-403
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoNEG
CoNEG
Negate Accumulator
Group
Arithmetic Instructions
Syntax
CoNEG
Source Operand(s)
ACC → 40-bit signed value
Destination Operand(s)
ACC → 40-bit signed value
Operation
(ACC) ← 0 - (ACC)
Description
The ACC register contents are subtracted from zero before being stored in the 40-bit
ACC register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoNEG
User Manual
Format
A3 00 32 rrr0:0000
8-404
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoNEG
CoNEG
Negate Accumulator with Round
Group
Arithmetic Instructions
Syntax
CoNEG rnd
Source Operand(s)
ACC → 40-bit signed value
Destination Operand(s)
ACC → 40-bit signed value
Operation
(ACC) ← 0 - (ACC) + 00 0000 8000h
(MAL) ← 0
Description
The ACC register contents are subtracted from zero and the result is rounded before
being stored in the 40-bit ACC register. The MAL register is cleared.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoNEG
User Manual
rnd
Format
A3 00 72 rrr0:0000
8-405
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoNOP
CoNOP
No-Operation
Group
Arithmetic Instructions
Syntax
CoNOP
Source Operand(s)
none
Destination Operand(s)
none
Operation
No Operation
Description
Modifies the address pointers.
MAC Flags
MV
-
MSL
MV
MSL
ME
MSV
MC
MZ
MN
ME
-
MSV
-
MC
-
MZ
-
MN
-
Sat.
no
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
CoNOP
CoNOP
CoNOP
User Manual
[IDXi*] , [Rwm*]
[IDXi*]
[Rwm*]
Format
93 Xm 5A rrr0:0qqq
93 X0 5A rrr0:0001
93 1m 5A rrr0:0qqq
8-406
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoRND
CoRND
Round Accumulator
Group
Shift Instructions
Syntax
CoRND
Source Operand(s)
ACC → 40-bit signed value
Destination Operand(s)
ACC → 40-bit signed value signed value
Operation
(ACC) ← (ACC) + 00 0000 8000h
(MAL) ← 0
Description
Rounds the ACC register contents by adding 00 0000 8000h and stores the result in the
ACC register and the lower part of the ACC register. MAL, is cleared.
Note: CoRND is a shortname for CoASHR #0, rnd
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic overflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic overflow occurred. Not affected otherwise.
MC
Set if a carry is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoRND
User Manual
Format
A3 00 B2 rrr0:0000
8-407
Bytes
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoSHL
CoSHL
Accumulator Logical Shift Left
Group
Shift Instructions
Syntax
CoSHL op1
Source Operand(s)
op1 → 5-bit unsigned data
Destination Operand(s)
ACC → 40-bit signed value
Operation
(count) ← (op1)
(C) <- (ACC[39])
DO WHILE ((count) ≠ 0)
(C) ← (ACC[39])
(ACC[n]) ← (ACC[n-1]) [n=39...1]
(ACC[0]) ← 0
(count) ← (count) -1
END WHILE
Description
Shifts the 40-bit ACC register contents left by the number of times specified by the
operand op1. The least significant bits of the result are filled with zeros accordingly.
Only shift values from 0 to 16 (inclusive) are allowed. op1 can be either a 5-bit unsigned
immediate data (the shift range is from 0 to 16 in this case) or the four least significant
bits (the shift range is from 0 to 15 in that case) of any register directly or indirectly
addressed operand.
Note: For this instruction only, the saturation is computed using the 40-bit result. So a
sign shifted over the 40 bit result is disregarded.
MAC Flags
MV
0
MSL
*
ME
*
MSV
-
MC
*
MZ
*
MN
*
Sat.
yes
MV
MSL
Always cleared.
Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Not affected.
MC
Carry flag is set according to the last most significant bit shifted out of
ACC or according to the sign of ACC.
MZ
Set if result equals zero. Cleared otherwise.
User Manual
8-408
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoSHL
CoSHL
CoSHL
User Manual
#data5
Rwn
[Rwm*]
Format
A3 00 82 rrr#:#
A3 nn 8A rrr0:0000
83 mm 8A rrr0:0qqq
8-409
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoSHR
CoSHR
Accumulator Logical Shift Right
Group
Shift Instructions
Syntax
CoSHR op1
Source Operand(s)
op1 → 5-bit unsigned data
Destination Operand(s)
ACC → 40-bit signed value
Operation
(count) ← (op1)
(C) ← 0
DO WHILE (count) ≠ 0
((ACC[n]) ← (ACC[n+1]) [n=0...38]
(ACC[39]) ← 0
(count) ← (count) -1
END WHILE
Description
Shifts the 40-bit ACC register contents right the number of times as specified by the
operand op1. The most significant bits of the result are filled with zeros accordingly.
Only shift values from 0 to 16 (inclusive) are allowed. op1 can be either a 5-bit unsigned
immediate data (the shift range is from 0 to 16 in this case) or the four least significant
bits (the shift range is from 0 to 15 in that case) of any register directly or indirectly
addressed operand. The MS bit of the MCW register does not affect the result.
MAC Flags
MV
0
MSL
MV
MSL
ME
MSV
MC
MZ
MN
User Manual
ME
*
MSV
-
MC
0
MZ
*
MN
*
Sat.
no
Always cleared.
Not affected.
Set if the MAE is used. Cleared otherwise.
Not affected.
Always cleared.
Set if result equals zero. Cleared otherwise.
Set if the most significant bit of the result is set. Cleared otherwise.
8-410
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Encoding
Mnemonic
CoSHR
CoSHR
CoSHR
User Manual
#data5
Rwn
[Rwm*]
Format
A3 00 92 rrr#:#
A3 nn 9A rrr0:0000
83 mm 9A rrr0:0qqq
8-411
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoSTORE
CoSTORE
Store a MAC-Unit Register
Group
Data Movement Instructions
Syntax
CoSTORE op1, op2
Source Operand(s)
op2 → WORD
Destination Operand(s)
op1 → WORD
Operation
(op1) ← (op2)
Description
Moves the contents of a MAC-Unit register specified by the source operand op2 to the
location specified by the destination operand op1.
MAC Flags
MV
-
MSL
MV
MSL
ME
MSV
MC
MZ
MN
ME
-
MSV
-
MC
-
MZ
-
MN
-
Sat.
no
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Not affected.
Encoding
Mnemonic
CoSTORE
CoSTORE
User Manual
Rwn , CoReg
[Rwn*] , CoReg
Format
C3 nn wwww:w000 rrr0:0000
B3 nn wwww:w000 rrr0:0qqq
8-412
Bytes
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoSUB
CoSUB
Subtract
Group
Arithmetic Instructions
Syntax
CoSUB op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op2) || (op1)
(ACC) ← (ACC) - (tmp)
Description
Subtracts a 40-bit operand from the 40-bit ACC contents and stores the result in the
ACC register. The 40-bit operand is a sign-extended result of the concatenation of the
two source operands op1 (LSW) and op2 (MSW).
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoSUB
CoSUB
CoSUB
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 0A rrr0:0000
83 nm 0A rrr0:0qqq
93 Xm 0A rrr0:0qqq
8-413
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoSUB2
CoSUB2
Subtract
Group
Arithmetic Instructions
Syntax
CoSUB2 op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← 2 * (op2) || (op1)
(ACC) ← (ACC) - (tmp)
Description
Subtracts a 40-bit operand from the 40-bit ACC contents and stores the result in the
ACC register. The 40-bit operand is a sign-extended result of the concatenation of the
two source operands op1 (LSW) and op2 (MSW). The 40-bit operand is then multiplied
by two before being subtracted from the ACC register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoSUB2
CoSUB2
CoSUB2
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 4A rrr0:0000
83 nm 4A rrr0:0qqq
93 Xm 4A rrr0:0qqq
8-414
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoSUB2R
CoSUB2R
Subtract
Group
Arithmetic Instructions
Syntax
CoSUB2R op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← 2 * (op2) || (op1)
(ACC) ← (tmp) - (ACC)
Description
Subtracts the 40-bit ACC contents from a 40-bit operand and stores the result in the
ACC register. The 40-bit operand is a sign-extended result of the concatenation of the
two source operands op1 (LSW) and op2 (MSW). The 40-bit operand is then multiplied
by two before being subtracted from the ACC register.
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoSUB2R
CoSUB2R
CoSUB2R
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 52 rrr0:0000
83 nm 52 rrr0:0qqq
93 Xm 52 rrr0:0qqq
8-415
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
CoSUBR
CoSUBR
Subtract
Group
Arithmetic Instructions
Syntax
CoSUBR op1, op2
Source Operand(s)
op1, op2 → WORD
Destination Operand(s)
ACC → 40-bit signed value
Operation
(tmp) ← (op2) || (op1)
(ACC) ← (tmp) - (ACC)
Description
Subtracts the 40-bit ACC contents from a 40-bit operand and stores the result in the
ACC register. The 40-bit operand is a sign-extended result of the concatenation of the
two source operands op1 (LSW) and op2 (MSW).
MAC Flags
MV
*
MSL
*
ME
*
MSV
*
MC
*
MZ
*
MN
*
Sat.
yes
MV
Set if an arithmetic underflow occurred, i.e. the result cannot be
represented in the 40-bit data type. Cleared otherwise.
MSL Set if the contents of ACC is automatically saturated. Not affected
otherwise.
ME
Set if the MAE is used. Cleared otherwise.
MSV Set if an arithmetic underflow occurred. Not affected otherwise.
MC
Set if a borrow is generated. Cleared otherwise.
MZ
Set if result equals zero. Cleared otherwise.
MN
Set if the most significant bit of the result is set. Cleared otherwise.
Encoding
Mnemonic
CoSUBR
CoSUBR
CoSUBR
User Manual
Rwn , Rwm
Rwn , [Rwm*]
[IDXi*] , [Rwm*]
Format
A3 nm 12 rrr0:0000
83 nm 12 rrr0:0qqq
93 Xm 12 rrr0:0qqq
8-416
Bytes
4
4
4
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
8.3
Instructions for OCDS/ITC injection and System Control
The following table gives a brief overview of the instructions that are defined especially
for injections via the Interrupt and PEC controller and for debugging reasons by the
OCDS. All instruction are 32 bit wide and overlap the existing instruction set. All these
instructuions are not modifying the PSW except direct writes to the PSW and the ITRAP/
ITRAPS instruction that adjust the level inside the PSW. All these instructions are only
available for injection.
operand
symbol
size
comment
mem24
MM2 MM0 MM1
24
direct 24 bit address for memory access.
The format MM2 MM0 MM1 means that the 24
bit address (byte2,byte1,byte0) has to be
presented in the order byte2, byte0, byte1.
#addr23
aa aa a:aaa
23
direct 23bit (to be LSB extended by zero) for
program access.
#banksel2
ss
2
selection of local/global banks
00
10
11
01
global register bank
local register bank 1
local register bank 2
reserved
#data23
dd dd d:ddd
23
direct 23bit (to be LSB extended by zero) data
to be written to CSP/IP.
Rx
x
4
word GPR address
Rbx
Table 8-1
x
4
Used shortcuts
byte GPR address
Mnemonic
Operands
Opcode
Cycle
Comment
OLOAD
mem24
0D MM2 MM0 MM1
1
reads word from
memory and
writes to OCDS
OSTORE
mem24
1D MM2 MM0 MM1
1
reads word from
OCDS and writes
to memory
Table 8-2
User Manual
Instructions for Injection only
8-417
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Mnemonic
Operands
Opcode
Cycle
Comment
OLOADB
mem24
2D MM2 MM0 MM1
1
reads byte from
memory and
writes to OCDS
OSTOREB
mem24
3D MM2 MM0 MM1
1
reads byte from
OCDS and writes
to memory
OLOAD
Rx, #banksel2
4D ss00:x 00 00
1
reads word from
GPR and writes
to OCDS
OSTORE
Rx, #banksel2
5D ss00:x 00 00
1
reads word from
OCDS and writes
to GPR
OLOADB
Rbx, #banksel2
6D ss00:x 00 00
1
reads byte from
GPR and writes
to OCDS
OSTOREB
Rbx, #banksel2
7D ss00:x 00 00
1
reads byte from
OCDS and writes
to GPR
MOVCSIP
#data23
9D dd dd d:ddd0
1
writes CSP/IP
register to force a
program brnach
8D 00 00 00
1
reads the current
instruction
pointer and
writes it to OCDS
OLOADIP
ITRAP
#addr23,
#banksel2
10ss:B aa aa a:aaa0
4
Interrupt Trap
with absolut
address
ITRAPS
#trap10,
#banksel2
11ss:B 00 0t t:tt00“
4
Short Interrupt
Trap with10 bit
trap number
using VECSEG
Table 8-2
User Manual
Instructions for Injection only
8-418
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
Mnemonic
Operands
Opcode
Cycle
Comment
PEC1)
mem24
CD MM2 MM0 MM1
1
word PEC
transfer started
by ITC
DPEC1)
mem24
DD MM2 MM0 MM1
1
word PEC
transfer started
by OCDS
PECB1)
mem24
AD MM2 MM0 MM1
1
byte PEC
transfer started
by ITC
DPECB1)
mem24
BD MM2 MM0 MM1
1
byte PEC
transfer started
by OCDS
TLOAD
mem24
8A MM2 MM0 MM1
1
reads memory
and writes result
to trace bus
TLOAD
Rx, #banksel2
CA ss00:x 00 00
1
reads GPR and
writes result to
trace bus
INOP
9A 00 00 00
AA 00 00 00
BA 00 00 00
DA 00 00 00
EA 00 00 00
FA 00 00 00
1
injected NOP
(reserved for
later use)
CXLOAD
ED 00 00 00
11
internal
instruction used
for switch context
CXSW
FD 00 00 00
19
internal
instruction used
for switch context
Table 8-2
1)
Instructions for Injection only
The shown operand specifies the source address for the PEC operation. For the destination address a
dedicated CPU input is provided.
User Manual
8-419
V 1.7, 2001-01
User Manual
C166S V2
Detailed Instruction Description
User Manual
8-420
V 1.7, 2001-01
User Manual
C166S V2
Summary of CPU/Subsystem Registers
9
Summary of CPU/Subsystem Registers
This chapter summarizes all registers implemented in the C166S V2 CPU. There are two
register types: the General Purpose Registers (GPR) and the CPU-Special Function
Registers (CSFR). GPRs are the working registers of the arithmetic and logic operations
and may be also used as address pointers indirect addressing modes. CSFRs are the
control registers of the C166S V2 CPU. The register set for the PEC and Interrupt
Controller is listed. For easy reference, the SFRs are ordered in two different ways:
• Sorted by the address, to identify a register at a given address.
• Sorted by the register name, to find an address of a specific register.
9.1
General Purpose Registers (GPRs)
The General Purpose Registers (GPRs) are the working registers of the C166S V2 CPU.
All GPRs are bit addressable.
Table 9-1
Addressing Modes to Access Word–GPRs
4-Bit
Description
Name Physical 8-Bit
Address Address Address
Reset
Value
1)
R0
(CP)+0
F0H
0h
General Purpose Word Register R0
UUUUH
R1
(CP)+2
F1H
1h
General Purpose Word Register R1
UUUUH
R2
(CP)+4
F2H
2h
General Purpose Word Register R2
UUUUH
R3
(CP)+6
F3H
3h
General Purpose Word Register R3
UUUUH
R4
(CP)+8
F4H
4h
General Purpose Word Register R4
UUUUH
R5
(CP)+10 F5H
5h
General Purpose Word Register R5
UUUUH
R6
(CP)+12 F6H
6h
General Purpose Word Register R6
UUUUH
R7
(CP)+14 F7H
7h
General Purpose Word Register R7
UUUUH
R8
(CP)+16 F8H
8h
General Purpose Word Register R8
UUUUH
R9
(CP)+18 F9H
9h
General Purpose Word Register R9
UUUUH
R10
(CP)+20 FAH
Ah
General Purpose Word Register R10 UUUUH
R11
(CP)+22 FBH
Bh
General Purpose Word Register R11 UUUUH
R12
(CP)+24 FCH
Ch
General Purpose Word Register R12 UUUUH
R13
(CP)+26 FDH
Dh
General Purpose Word Register R13 UUUUH
R14
(CP)+28 FEH
Eh
General Purpose Word Register R14 UUUUH
R15
(CP)+30 FFH
Fh
General Purpose Word Register R15 UUUUH
1)
Addressing mode only usable if the GPR bank is memory mapped.
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Summary of CPU/Subsystem Registers
The first 8 GPRs (R7...R0) may be also accessed bytewise. Unlike SFRs, writing to a
GPR byte does not affect another byte of the GPR.
The following byte-accessible registers have special names.
Table 9-2
Addressing Modes to Access Byte–GPRs
4-Bit
Description
Name Physical 8-Bit
Address Address Address
Reset
Value
1)
RL0
(CP)+0
F0H
0h
General Purpose Byte Register RL0
UUH
RH0
(CP)+1
F1H
1h
General Purpose Byte Register RL1
UUH
RL1
(CP)+2
F2H
2h
General Purpose Byte Register RL2
UUH
RH1
(CP)+3
F3H
3h
General Purpose Byte Register RL3
UUH
RL2
(CP)+4
F4H
4h
General Purpose Byte Register RL4
UUH
RH2
(CP)+5
F5H
5h
General Purpose Byte Register RL5
UUH
RL3
(CP)+6
F6H
6h
General Purpose Byte Register RL6
UUH
RH3
(CP)+7
F7H
7h
General Purpose Byte Register RL7
UUH
RL4
(CP)+8
F8H
8h
General Purpose Byte Register RL8
UUH
RH4
(CP)+9
F9H
9h
General Purpose Byte Register RL9
UUH
RL5
(CP)+10 FAH
Ah
General Purpose Byte Register RL10 UUH
RH5
(CP)+11 FBH
Bh
General Purpose Byte Register RL11 UUH
RL6
(CP)+12 FCH
Ch
General Purpose Byte Register RL12 UUH
RH6
(CP)+13 FDH
Dh
General Purpose Byte Register RL13 UUH
RL7
(CP)+14 FEH
Eh
General Purpose Byte Register RL14 UUH
RH7
(CP)+15 FFH
Fh
General Purpose Byte Register RL15 UUH
1)
Addressing mode only usable if the GPR bank is memory mapped.
The 8-bit short addresses F0H...FEH within the ESFR area are reserved and provide
access to the current register bank via short register addressing modes. The
GPRs are mirrored to the ESFR area which allows access to the current register
bank even after switching register spaces (see example below).
MOV
EXTR
MOV
User Manual
R5, DP3 ;GPR access via SFR area
#1
R5, ODP3 ;GPR access via ESFR area
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Summary of CPU/Subsystem Registers
9.2
Core Special Function Registers
9.2.1
Ordered by Name
Table 9-3 lists all CSFRs implemented in the C166S V2 CPU, in alphabetical order.
Bit addressable CSFRs are marked with the letter “b” in the “Name” column.
CSFRs within the Extended CSFR-Space (ECSFRs) are marked with the letter “E” in
the “8-Bit Address” column.
Table 9-3
Addressing Modes to Access Core-SFRs: Ordered by Name
Name
Physical 8-Bit
Address Address
Description
Reset
Value
CP
FE10H
08H
Context Pointer
FC00H
CPUCON1
FE18H
0CH
Core Control Register
0000H
CPUCON2
FE1AH
0DH
Core Control Register
0000H
CPUID
F00CH
E-06H
CPU Identification Register
03??H1)
CSP
FE08H
04H
Code Segment Pointer
(8 bits, not directly writable)
0000H
DPP0
FE00H
00H
Data Page Pointer 0 (10 bits)
0000H
DPP1
FE02H
01H
Data Page Pointer 1 (10 bits)
0001H
DPP2
FE04H
02H
Data Page Pointer 2 (10 bits)
0002H
DPP3
FE06H
03H
Data Page Pointer 3 (10 bits)
0003H
IDX0
b FF08H
84H
MAC Address Pointer 0
0000H
IDX1
b FF0AH
85H
MAC Address Pointer 1
0000H
MAL
FE5CH
2EH
MAC Accumulator – Low Word
0000H
MAH
FE5EH
2FH
MAC Accumulator – High Word
0000H
MCW
b FFDCH
EEH
MAC Control Word
0000H
MDC
b FF0EH
87H
Multiply Divide Control Register
0000H
MDH
FE0CH
06H
Multiply Divide Register – High Word
0000H
MDL
FE0EH
07H
Multiply Divide Register – Low Word
0000H
MRW
b FFDAH
EDH
MAC Repeat Word
0000H
MSW
b FFDEH
EFH
MAC Status Word
0200H
ONES
b FF1EH
8FH
Constant Value 1’s Register (read only)
FFFFH
PSW
b FF10H
88H
Program Status Word
0000H
QX0
F000H
E-00H
MAC Offset Register X0
0000H
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Table 9-3
Addressing Modes to Access Core-SFRs: Ordered by Name (cont’d)
Name
Physical 8-Bit
Address Address
Description
Reset
Value
QX1
F002H
E-01H
MAC Offset Register X1
0000H
QR0
F004H
E-02H
MAC Offset Register R0
0000H
QR1
F006H
E-03H
MAC Offset Register R1
0000H
SP
FE12H
09H
Stack Pointer
FC00H
SPSEG b FF0CH
86H
Stack Pointer Segment Register
0000H
STKOV
FE14H
0AH
Stack Overflow Register
FA00H
STKUN
FE16H
0BH
Stack Underflow Register
FC00H
b FFACH
D6H
Trap Flag Register
0000H
VECSEG b FF12H
89H
Vector Table Segment Register
????H2)
ZEROS b FF1CH
8EH
Constant Value 0’s Register (read only)
0000H
TFR
1)
‘??’: defined by reset configuration
2)
‘????’: defined by reset configuration
9.2.2
Ordered by Address
Table 9-4 lists all CSFRs implemented in the C166S V2 ordered by physical address.
Bit addressable CSFRs are marked with the letter “b” in the “Name” column.
CSFRs within the Extended SFR-Space (ESFRs) are marked with the letter “E” in the
“8-Bit Address” column.
Table 9-4
Addressing Modes to Access Core-SFRs: Ordered by Address
Name
Physical 8-Bit
Description
Address Address
QX0
F000H
E-00H
MAC Offset Register X0
0000H
QX1
F002H
E-01H
MAC Offset Register X1
0000H
QR0
F004H
E-02H
MAC Offset Register R0
0000H
QR1
F006H
E-03H
MAC Offset Register R1
0000H
CPUID
F00CH
E-06H
CPU Identification Register
03??H1)
DPP0
FE00H
00H
Data Page Pointer 0 (10 bits)
0000H
DPP1
FE02H
01H
Data Page Pointer 1 (10 bits)
0001H
DPP2
FE04H
02H
Data Page Pointer 2 (10 bits)
0002H
DPP3
FE06H
03H
Data Page Pointer 3 (10 bits)
0003H
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Value
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Summary of CPU/Subsystem Registers
Table 9-4
Addressing Modes to Access Core-SFRs: Ordered by Address
Name
Physical 8-Bit
Description
Address Address
Reset
Value
CSP
FE08H
04H
Code Segment Pointer
(8 bits, not directly writable)
0000H
MDH
FE0CH
06H
Multiply Divide Register – High Word
0000H
MDL
FE0EH
07H
Multiply Divide Register – Low Word
0000H
CP
FE10H
08H
Context Pointer
FC00H
SP
FE12H
09H
Stack Pointer
FC00H
STKOV
FE14H
0AH
Stack Overflow Register
FA00H
STKUN
FE16H
0BH
Stack Underflow Register
FC00H
CPUCON1
FE18H
0CH
Core Control Register
0000H
CPUCON2
FE1AH
0DH
Core Control Register
0000H
MAL
FE5CH
2EH
MAC Accumulator – Low Word
0000H
MAH
FE5EH
2FH
MAC Accumulator – High Word
0000H
IDX0
b FF08H
84H
MAC Address Pointer 0
0000H
IDX1
b FF0AH
85H
MAC Address Pointer 1
0000H
SPSEG b FF0CH
86H
Stack Pointer Segment Register
0000H
MDC
b FF0EH
87H
Multiply Divide Control Register
0000H
PSW
b FF10H
88H
Program Status Word
0000H
VECSEG b FF12H
89H
Vector Table Segment Register
????H2)
ZEROS b FF1CH
8EH
Constant Value 0s Register (read only)
0000H
ONES
b FF1EH
8FH
Constant Value 1s Register (read only)
FFFFH
TFR
b FFACH
D6H
Trap Flag Register
0000H
MRW
b FFDAH
EDH
MAC Repeat Word
0000H
MCW
b FFDCH
EEH
MAC Control Word
0000H
MSW
b FFDEH
EFH
MAC Status Word
0200H
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1)
‘??’: defined by reset configuration
2)
‘????’: defined by reset configuration
User Manual
User Manual
C166S V2
Summary of CPU/Subsystem Registers
9.3
Register Overview Interrupt and Peripheral Event Controller
9.3.1
Ordered by Name
Table 9-5 lists all xSFRs that are implemented in the C166S V2 Interrupt and Peripheral
Event Controller, ordered by name.
Bit addressable SFRs are marked with the letter “b” in the “Name” column.
SFRs within the Extended SFR-Space (ESFRs) are marked with the letter “E” in the
“8-Bit Address” column.
Table 9-5
Register Overview Interrupt and PEC: Ordered by Name
Name
Physical
Address
8-bit
Description
Address
Reset
Value
BNKSEL0
EC20H
--
Bank Selection Register 0
0000H
BNKSEL1
EC22H
--
Bank Selection Register 1
0000H
BNKSEL2
EC24H
--
Bank Selection Register 2
0000H
BNKSEL3
EC26H
--
Bank Selection Register 3
0000H
DSTP0
EC42H
--
PEC Channel 0 Destination Pointer
0000H
DSTP1
EC46H
--
PEC Channel 1 Destination Pointer
0000H
DSTP2
EC4AH
--
PEC Channel 2 Destination Pointer
0000H
DSTP3
EC4EH
--
PEC Channel 3 Destination Pointer
0000H
DSTP4
EC52H
--
PEC Channel 4 Destination Pointer
0000H
DSTP5
EC56H
--
PEC Channel 5 Destination Pointer
0000H
DSTP6
EC5AH
--
PEC Channel 6 Destination Pointer
0000H
DSTP7
EC5EH
--
PEC Channel 7 Destination Pointer
0000H
E-C0H
End of PEC Interrupt Control Reg.
0000H
EOPIC1)
b F180H
FINT0ADDR
EC02H
--
Fast Interrupt 0 Address Register
0000H
FINT0CSP
EC00H
--
Fast Interrupt 0 CSP Register
0000H
FINT1ADDR
EC06H
--
Fast Interrupt 1 Address Register
0000H
FINT1CSP
EC04H
--
Fast Interrupt 1 CSP Register
0000H
IRQxIC1)
xxxxH
xxH
Interrupt x Control Register
0000H
PECC0
FEC0H
60H
PEC Channel 0 Control Register
0000H
PECC1
FEC2H
61H
PEC Channel 1 Control Register
0000H
PECC2
FEC4H
62H
PEC Channel 2 Control Register
0000H
PECC3
FEC6H
63H
PEC Channel 3 Control Register
0000H
PECC4
FEC8H
64H
PEC Channel 4 Control Register
0000H
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Table 9-5
Register Overview Interrupt and PEC: Ordered by Name (cont’d)
Name
Physical
Address
8-bit
Description
Address
Reset
Value
PECC5
FECAH
65H
PEC Channel 5 Control Register
0000H
PECC6
FECCH
66H
PEC Channel 6 Control Register
0000H
PECC7
FECEH
67H
PEC Channel 7 Control Register
0000H
PECISNC
b FFA8H
D4H
PEC Interrupt Subnode Control Reg.
0000H
PECSEG0
EC80H
--
PEC Pointer 0 Segment Address Reg. 0000H
PECSEG1
EC82H
--
PEC Pointer 1 Segment Address Reg. 0000H
PECSEG2
EC84H
--
PEC Pointer 2 Segment Address Reg. 0000H
PECSEG3
EC86H
--
PEC Pointer 3 Segment Address Reg. 0000H
PECSEG4
EC88H
--
PEC Pointer 4 Segment Address Reg. 0000H
PECSEG5
EC8AH
--
PEC Pointer 5 Segment Address Reg. 0000H
PECSEG6
EC8C
--
PEC Pointer 6 Segment Address Reg. 0000
PECSEG7
EC8E
--
PEC Pointer 7 Segment Address Reg. 0000
SRCP0
EC40
--
PEC Channel 0 Source Pointer
0000
SRCP1
EC44
--
PEC Channel 1 Source Pointer
0000
SRCP2
EC48
--
PEC Channel 2 Source Pointer
0000
SRCP3
EC4C
--
PEC Channel 3 Source Pointer
0000
SRCP4
EC50
--
PEC Channel 4 Source Pointer
0000
SRCP5
EC54
--
PEC Channel 5 Source Pointer
0000
SRCP6
EC58
--
PEC Channel 6 Source Pointer
0000
SRCP7
EC5C
--
PEC Channel 7 Source Pointer
0000
1)
The implementation and assignment of these Interrupt Control Registers are product specific.
9.3.2
Ordered by Address
Table 9-6 lists all xSFRs that are implemented in the C166S V2 Interrupt and Peripheral
Event Controller ordered by address.
Bit addressable SFRs are marked with the letter “b” in the “Name” column.
SFRs within the Extended SFR-Space (ESFRs) are marked with the letter “E” in the
“8-Bit Address” column.
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Table 9-6
Register Overview Interrupt and PEC: Ordered by Address
Name
Physical
Address
8-bit
Description
Address
Reset
Value
FINT0CSP
EC00H
--
Fast Interrupt 0 CSP Register
0000H
FINT0ADDR
EC02H
--
Fast Interrupt 0 Address Register
0000H
FINT1CSP
EC04H
--
Fast Interrupt 1 CSP Register
0000H
FINT1ADDR
EC06H
--
Fast Interrupt 1 Address Register
0000H
BNKSEL0
EC20H
--
Bank Selection Register 0
0000H
BNKSEL1
EC22H
--
Bank Selection Register 1
0000H
BNKSEL2
EC24H
--
Bank Selection Register 2
0000H
BNKSEL3
EC26H
--
Bank Selection Register 3
0000H
SRCP0
EC40H
--
PEC Channel 0 Source Pointer
0000H
DSTP0
EC42H
--
PEC Channel 0 Destination Pointer
0000H
SRCP1
EC44H
--
PEC Channel 1 Source Pointer
0000H
DSTP1
EC46H
--
PEC Channel 1 Destination Pointer
0000H
SRCP2
EC48H
--
PEC Channel 2 Source Pointer
0000H
DSTP2
EC4AH
--
PEC Channel 2 Destination Pointer
0000H
SRCP3
EC4CH
--
PEC Channel 3 Source Pointer
0000H
DSTP3
EC4EH
--
PEC Channel 3 Destination Pointer
0000H
SRCP4
EC50H
--
PEC Channel 4 Source Pointer
0000H
DSTP4
EC52H
--
PEC Channel 4 Destination Pointer
0000H
SRCP5
EC54H
--
PEC Channel 5 Source Pointer
0000H
DSTP5
EC56H
--
PEC Channel 5 Destination Pointer
0000H
SRCP6
EC58H
--
PEC Channel 6 Source Pointer
0000H
DSTP6
EC5AH
--
PEC Channel 6 Destination Pointer
0000H
SRCP7
EC5CH
--
PEC Channel 7 Source Pointer
0000H
DSTP7
EC5EH
--
PEC Channel 7 Destination Pointer
0000H
PECSEG0
EC80H
--
PEC Pointer 0 Segment Address Reg. 0000H
PECSEG1
EC82H
--
PEC Pointer 1 Segment Address Reg. 0000H
PECSEG2
EC84H
--
PEC Pointer 2 Segment Address Reg. 0000H
PECSEG3
EC86H
--
PEC Pointer 3 Segment Address Reg. 0000H
PECSEG4
EC88H
--
PEC Pointer 4 Segment Address Reg. 0000H
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Table 9-6
Register Overview Interrupt and PEC: Ordered by Address (cont’d)
Name
Physical
Address
8-bit
Description
Address
PECSEG5
EC8AH
--
PEC Pointer 5 Segment Address Reg. 0000H
PECSEG6
EC8CH
--
PEC Pointer 6 Segment Address Reg. 0000H
PECSEG7
EC8EH
--
PEC Pointer 7 Segment Address Reg. 0000H
E-C0H
End of PEC Interrupt Control Reg.
0000H
EOPIC1)
b F180H
Reset
Value
PECC0
FEC0H
60H
PEC Channel 0 Control Register
0000H
PECC1
FEC2H
61H
PEC Channel 1 Control Register
0000H
PECC2
FEC4H
62H
PEC Channel 2 Control Register
0000H
PECC3
FEC6H
63H
PEC Channel 3 Control Register
0000H
PECC4
FEC8H
64H
PEC Channel 4 Control Register
0000H
PECC5
FECAH
65H
PEC Channel 5 Control Register
0000H
PECC6
FECCH
66H
PEC Channel 6 Control Register
0000H
PECC7
FECEH
67H
PEC Channel 7 Control Register
0000H
xxxxH
xxH
Interrupt x Control Register
0000H
D0H
PEC Interrupt Subnode Control Reg.
0000H
1)
IRQxIC
PECISNC
1)
b FFA8H
The implementation and assignment of theses Interrupt Control Registers are product specific.
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Summary of CPU/Subsystem Registers
9.4
Register Overview External Bus Controller
9.4.1
Ordered by Name
Table 9-7
Register Overview EBC: Ordered by Name
Name
Physical
Address
8-Bit
Address
Description
Reset
Value
ADDRSEL1
EE1EH
--
Address Window Selection for CS1
0000H
ADDRSEL2
EE26H
--
Address Window Selection for CS2
0000H
ADDRSEL3
EE 2EH
--
Address Window Selection for CS3
0000H
ADDRSEL4
EE36H
--
Address Window Selection for CS4
0000H
ADDRSEL5
EE 3EH
--
Address Window Selection for CS5
0000H
ADDRSEL6
EE46H
--
Address Window Selection for CS6
0000H
ADDRSEL7
EE 4EH
--
Address Window Selection for CS7
0000H
EBCMOD0
EE00H
--
Alternate Function of EBC Pins
00F0H
EBCMOD1
EE02H
--
Global Behavior of EBC
0000H
FCONCS0
EE12H
--
Function Control for CS0
0021H
FCONCS1
EE1AH
--
Function Control for CS1
0000H
FCONCS2
EE22H
--
Function Control for CS2
0000H
FCONCS3
EE2AH
--
Function Control for CS3
0000H
FCONCS4
EE32H
--
Function Control for CS4
0000H
FCONCS5
EE 3AH
--
Function Control for CS5
0000H
FCONCS6
EE 42H
--
Function Control for CS6
0000H
FCONCS7
EE4AH
--
Function Control for CS7
0000H
TCONCS0
EE10H
--
Timing Control for CS0
6243H
TCONCS1
EE18H
--
Timing Control for CS1
0000H
TCONCS2
EE20H
--
Timing Control for CS2
0000H
TCONCS3
EE28H
--
Timing Control for CS3
0000H
TCONCS4
EE 30H
--
Timing Control for CS4
0000H
TCONCS5
EE38H
--
Timing Control for CS5
0000H
TCONCS6
EE40H
--
Timing Control for CS6
0000H
TCONCS7
EE48H
--
Timing Control for CS7
0000H
TCONCSMM
EE0CH
--
Timing Control for Monitor Memory
6243H
TCONCSSM
EE0EH
--
Timing Control for Startup Memory
6243H
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Summary of CPU/Subsystem Registers
9.4.2
Ordered by Address
Table 9-8
Register Overview EBC: Ordered by Name
Name
Physical
Address
8-Bit
Address
Description
Reset
Value
EBCMOD0
EE00H
--
Alternate Function of EBC Pins
00F0H
EBCMOD1
EE02H
--
Global Behavior of EBC
0000H
TCONCSMM
EE0CH
--
Timing Control for Monitor Memory
6243H
TCONCSSM
EE0EH
--
Timing Control for Startup Memory
6243H
TCONCS0
EE10H
--
Timing Control for CS0
6243H
FCONCS0
EE12H
--
Function Control for CS0
0021H
TCONCS1
EE18H
--
Timing Control for CS1
0000H
FCONCS1
EE1AH
--
Function Control for CS1
0000H
ADDRSEL1
EE1EH
--
Address Window Selection for CS1
0000H
TCONCS2
EE20H
--
Timing Control for CS2
0000H
FCONCS2
EE22H
--
Function Control for CS2
0000H
ADDRSEL2
EE26H
--
Address Window Selection for CS2
0000H
TCONCS3
EE28H
--
Timing Control for CS3
0000H
FCONCS3
EE2AH
--
Function Control for CS3
0000H
ADDRSEL3
EE2EH
--
Address Window Selection for CS3
0000H
TCONCS4
EE30H
--
Timing Control for CS4
0000H
FCONCS4
EE32H
--
Function Control for CS4
0000H
ADDRSEL4
EE36H
--
address window selection for CS4
0000H
TCONCS5
EE38H
--
Timing Control for CS5
0000H
FCONCS5
EE3AH
--
Function Control for CS5
0000H
ADDRSEL5
EE3EH
--
Address Window Selection for CS5
0000H
TCONCS6
EE40H
--
Timing Control for CS6
0000H
FCONCS6
EE42H
--
Function Control for CS6
0000H
ADDRSEL6
EE46H
--
Address Window Selection for CS6
0000H
TCONCS7
EE48H
--
Timing Control for CS7
0000H
FCONCS7
EE4AH
--
Function Control for CS7
0000H
ADDRSEL7
EE 4EH
--
Address Window Selection for CS7
0000H
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Keyword Index
10
Keyword Index
This section lists a number of keywords which refer to specific details of the C166S V2
in terms of its architecture, its functional units or functions. This helps to quickly find the
answer to specific questions about the C166S V2.
A
E
Address Boundaries 99
Addressing Modes
CoREG Addressing Mode 63
IDX Indirect Addressing Mode 56
Indirect Addressing Mode 53
Long Adressing Mode 52
Short Addressing Modes 46
EBC 13
End of PEC Interrupt Sub Node 143
External Bus Controller 13
External Bus Idle State 169
External Interrupt 14
B
F
Fast Bank Switching 131
Bit Protection 71
Block Diagram ITC / PEC 119
BWT Bit 140
G
C
I
Central System Control 14
CGU 14
Clock Generation Unit 14
Context Pointer
Updating 43
Context Switch 40
Continuous PEC Transfers 140
COUNT Bit 140
CP Register 423, 425
CPUCON1 Register 423, 425
CPUCON2 Register 423, 425
CPUID Register 423, 424
CSP Register 423, 425
Cycle counts 194
ID Control 14
IDX0 Register 423, 425
IDX1 Register 423, 425
INC Bit 144
Instructions
ADD 212
ADDB 213
ADDC 214
ADDCB 215
AND 216
ANDB 217
ASHR 218
ATOMIC 220
BAND 221
BCLR 222
BCMP 223
BFLDH 224
BFLDL 225
BMOV 226
BMOVN 227
D
Data Page Boundaries 99
Data Page Pointer 49
Data Types 68
DMU 12
User Manual
General Purpose Register 100
GPR 100
10-433
V 1.7, 2001-01
User Manual
C166S V2
Keyword Index
CoMACu- 383
CoMACus 384, 385
CoMACus- 386
CoMAX 387
CoMIN 388
CoMOV 389
CoMUL 390, 392
CoMUL- 394
CoMULsu 395, 396
CoMULsu- 397
CoMULu 398, 399
CoMULu- 400
CoMULus 401, 402
CoMULus- 403
CoNEG 404, 405
CoNOP 406
CoRND 407
CoSHL 408
CoSHR 410
CoSTORE 412
CoSUB 413
CoSUB2 414
CoSUB2R 415
CoSUBR 416
CPL 242
CPLB 243
DISWDT 244
DIV 245
DIVL 246
DIVLU 247
DIVU 248
EINIT 249
ENWDT 250
EXTP 251
EXTPR 253
EXTR 255
EXTS 256
EXTSR 258
IDLE 260
JB 261
JBC 262
JMPA 264
JMPI 266
BOR 228
BSET 229
BXOR 230
CALLA 231
CALLI 233
CALLR 234
CALLS 235
CMP 236
CMPB 237
CMPD1 238
CMPD2 239
CMPI1 240
CMPI2 241
CoABS 316, 317
CoADD 318
CoADD2 319
CoASHR 320, 322
CoCMP 324
CoLOAD 325
CoLOAD- 326
CoLOAD2 327
CoLOAD2- 327, 328
CoMAC 329, 331
CoMAC- 333
CoMACM 335, 337
CoMACM- 339
CoMACMR 341, 343
CoMACMRsu 345, 347
CoMACMRu 348, 350
CoMACMRus 351, 353
CoMACMsu 354, 356
CoMACMsu- 357
CoMACMu 358, 360
CoMACMu- 361
CoMACMus 362, 364
CoMACMus- 365
CoMACR 366, 368
CoMACRsu 370, 372
CoMACRu 373, 374
CoMACRus 375, 377
CoMACsu 378, 379
CoMACsu- 380
CoMACu 381, 382
User Manual
10-434
V 1.7, 2001-01
User Manual
C166S V2
Keyword Index
JMPR 267
JMPS 268
JNB 269
JNBS 270
MOV 272
MOVB 274
MOVBS 276
MOVBZ 277
MUL 278
MULU 279
NEG 280
NEGB 281
NOP 282
OR 283
ORB 284
PCALL 285
POP 287
PRIOR 288
PUSH 289
PWRDN 290
RET 291
RETI 292
RETP 293
RETS 294
ROL 295
ROR 297
SBRK 299
SCXT 300
SHL 301
SHR 303
SRST 305
SRVWDT 306
SUB 307
SUBB 308
SUBC 309
SUBCB 310
TRAP 311
XOR 313
XORB 314
Interrrupt Control Register 140
Interrupt Jump Table Cache 125
Interrupt System 118
User Manual
J
JTAG 13
M
MAH Register 423, 425
MAL Register 423, 425
MCW Register 423, 425
MDC Register 423, 425
MDH Register 423, 425
MDL Register 423, 425
Memory
External 98
ROM 93
MRW Register 423, 425
MSW Register 423, 425
N
NMI 117
O
OCDS 13
ONES Register 423, 425
P
PEC 138
Channel Actions 144
Control Register 139
Pointer Address Handling 146
Transfer Count 140
Peripheral Event Controller 138
PMU 12
Power Saving Control 14
Program Memory Unit 12
Protected Bits 71
PSW Register 423, 425
Q
QR0 Register 424
QR1 Register 424
QX0 Register 423, 424
QX1 Register 424
10-435
V 1.7, 2001-01
User Manual
C166S V2
Keyword Index
R
Register
CP 423, 425
CPUCON1 423, 425
CPUCON2 423, 425
CPUID 423, 424
CSP 423, 425
DPP0 423, 424
DPP1 423, 424
DPP2 423, 424
DPP3 423, 424
IDX0 423, 425
IDX1 423, 425
MAH 423, 425
MAL 423, 425
MCW 423, 425
MDC 423, 425
MDH 423, 425
MDL 423, 425
MRW 423, 425
MSW 423, 425
ONES 423, 425
PSW 423, 425
QR0 424
QR1 424
QX0 423, 424
QX1 424
SP 424, 425
SPSEG 424, 425
STKOV 424, 425
STKUN 424, 425
TFR 424, 425
VECSEG 424, 425
xxIC 140
ZEROS 424, 425
Reset Control 13
SP Register 424, 425
SPSEG Register 424, 425
STKOV Register 424, 425
STKUN Register 424, 425
System Control Unit 13
T
TFR Register 424, 425
Traps 135
V
VECSEG Register 424, 425
W
Watchdog Timer 14
WDT 14
Z
ZEROS Register 424, 425
S
SCU 13
Segment Boundaries 99
SFR 96
Sleep mode 14
User Manual
10-436
V 1.7, 2001-01
437
Infineon goes for Business Excellence
“Business excellence means intelligent approaches and clearly
defined processes, which are both constantly under review and
ultimately lead to good operating results.
Better operating results and business excellence mean less
idleness and wastefulness for all of us, more professional
success, more accurate information, a better overview and,
thereby, less frustration and more satisfaction.”
Dr. Ulrich Schumacher
http://www.infineon.com
Published by Infineon Technologies AG