NEC MPD78C17GF-3BE 8-bit single-chip microcontroller Datasheet

87AD SERIES
µPD78C18
8-BIT SINGLE-CHIP MICROCONTROLLER
©
1991
Document No.
U10199EJ5V0UM00 (5th edition)
(Previous No.
IEU-1314)
Date Published August 1995 P
Printed in Japan
NOTES FOR CMOS DEVICES
1
PRECAUTION AGAINST ESD FOR SEMICONDUCTORS
Note:
Strong electric field, when exposed to a MOS device, can cause destruction of the gate oxide
and ultimately degrade the device operation. Steps must be taken to stop generation of static
electricity as much as possible, and quickly dissipate it once, when it has occurred. Environmental control must be adequate. When it is dry, humidifier should be used. It is recommended
to avoid using insulators that easily build static electricity. Semiconductor devices must be
stored and transported in an anti-static container, static shielding bag or conductive material.
All test and measurement tools including work bench and floor should be grounded. The
operator should be grounded using wrist strap. Semiconductor devices must not be touched
with bare hands. Similar precautions need to be taken for PW boards with semiconductor
devices on it.
2
HANDLING OF UNUSED INPUT PINS FOR CMOS
Note:
No connection for CMOS device inputs can be cause of malfunction. If no connection is
provided to the input pins, it is possible that an internal input level may be generated due to
noise, etc., hence causing malfunction. CMOS devices behave differently than Bipolar or NMOS
devices. Input levels of CMOS devices must be fixed high or low by using a pull-up or pull-down
circuitry. Each unused pin should be connected to VDD or GND with a resistor, if it is considered
to have a possibility of being an output pin. All handling related to the unused pins must be
judged device by device and related specifications governing the devices.
3
STATUS BEFORE INITIALIZATION OF MOS DEVICES
Note:
Power-on does not necessarily define initial status of MOS device. Production process of MOS
does not define the initial operation status of the device. Immediately after the power source
is turned ON, the devices with reset function have not yet been initialized. Hence, power-on
does not guarantee out-pin levels, I/O settings or contents of registers. Device is not initialized
until the reset signal is received. Reset operation must be executed immediately after poweron for devices having reset function.
QTOP is a trademark of NEC Corporation.
MS-DOS is a trademark of Microsoft Corporation.
PC/AT and PC DOS are trademarks of IBM Corporation.
The export of these products from Japan is regulated by the Japanese government. The export of some or all of
these products may be prohibited without governmental license. To export or re-export some or all of these
products from a country other than Japan may also be prohibited without a license from that country. Please call
an NEC sales representative.
The customer must judge
the need for license
: µPD78C11, 78C11A, 78C12A, 78C14, 78C14A, 78CP14CW, 78CP14G-36,
78CP14GF-3BE, 78CP14L, 78C18, 78CP18CW, 78CP18GF-3BE, 78CP18GQ-36,
78C11(A), 78C11A(A), 78C12A(A), 78C14(A), 78CP14(A), 78C18(A), 78CP18(A)
License not needed
: µPD78C10, 78C10A, 78CG14, 78CP14DW, 78CP14KB, 78CP14R, 78C17, 78CP18DW,
78CP18KB, 78C10(A), 78C10A(A), 78C17(A)
The information in this document is subject to change without notice.
No part of this document may be copied or reproduced in any form or by any means without the prior written
consent of NEC Corporation. NEC Corporation assumes no responsibility for any errors which may appear in
this document.
NEC Corporation does not assume any liability for infringement of patents, copyrights or other intellectual
property rights of third parties by or arising from use of a device described herein or any other liability arising
from use of such device. No license, either express, implied or otherwise, is granted under any patents,
copyrights or other intellectual property rights of NEC Corporation or others.
While NEC Corporation has been making continuous effort to enhance the reliability of its semiconductor devices,
the possibility of defects cannot be eliminated entirely. To minimize risks of damage or injury to persons or
property arising from a defect in an NEC semiconductor device, customer must incorporate sufficient safety
measures in its design, such as redundancy, fire-containment, and anti-failure features.
NEC devices are classified into the following three quality grades:
“Standard“, “Special“, and “Specific“. The Specific quality grade applies only to devices developed based on
a customer designated “quality assurance program“ for a specific application. The recommended applications
of a device depend on its quality grade, as indicated below. Customers must check the quality grade of each
device before using it in a particular application.
Standard: Computers, office equipment, communications equipment, test and measurement equipment,
audio and visual equipment, home electronic appliances, machine tools, personal electronic
equipment and industrial robots
Special: Transportation equipment (automobiles, trains, ships, etc.), traffic control systems, anti-disaster
systems, anti-crime systems, safety equipment and medical equipment (not specifically designed
for life support)
Specific: Aircrafts, aerospace equipment, submersible repeaters, nuclear reactor control systems, life
support systems or medical equipment for life support, etc.
The quality grade of NEC devices in “Standard“ unless otherwise specified in NEC's Data Sheets or Data Books.
If customers intend to use NEC devices for applications other than those specified for Standard quality grade,
they should contact NEC Sales Representative in advance.
Anti-radioactive design is not implemented in this product.
M7 94.11
INTRODUCTION
Intended Readership:
This manual is intended for engineers who require an understanding of 87AD series
products functions prior to designing an application system or an application program.
The relevant products are the following 87AD series CMOS version products.
• µPD78C10A, 78C11A, 78C10A(A), 78C11A(A)
• µPD78C12A, 78C12A(A)
• µPD78C14, 78C14A, 78CG14, 78CP14, 78C14(A), 78CP14(A)
• µPD78C17, 78C18, 78CP18, 78C17(A), 78C18(A), 78CP18(A)
Remark
µPD78C10, 78C11, 78C10(A), 78C11(A) have been maintenance products
since October 1991.
Purpose:
The purposes of this manual is that users understand the hardware functions of 87AD
series products shown in the organization below.
Organization:
This manual is mainly composed of the following contents.
• General description
• Pin functions
• Internal block functions
• Interrupt control functions
• External device accesses and timing
• PROM accesses
• Instruction set
• Operating precautions
Using This Information:
Use of this information requires general knowledge of electricity, logic circuits and
microcontrollers.
This manual describes the µPD78C18 as a representative product as long as there are
no differences in the functions. Using this manual as the other 87AD series (CMOS)
products manual, refer to the manual by changing "µPD78C18" to each product name.
For the µPD78CG14, refer to APPENDIX A INTRODUCTION TO PIGGYBACK PRODUCT.
For the "Special" quality grade product, refer to the manual by changing it to the
"Standard" quality grade product.
◆ For general understanding of the 87AD series (CMOS) product functions:
➡ Read in order of contents.
◆ For searching for an instruction function by mnemonics:
➡ Use APPENDIX C INDEX OF INSTRUCTIONS (ALPHABETICAL ORDER).
◆ For searching for mnemonics by the outline of functions:
➡ Search 14.6 Instruction Descriptions for the functions.
Usage examples in this manual is produced for the "Standard" quality
grade. Using this manual for the "Special" quality grade applications, make
use of parts and circuits actually used after checking the quality grade.
Operating Precaution
Be sure to read CHAPTER 15 OPERATING PRECAUTIONS in which operating
precautions of the 87AD series (CMOS) products are compiled. For the
latest information of this products, contact our salesman or special agent.
Legend:
Data notation weight
: Upper digits to the left, lower digits to the right
Notation of active low
: ××× (A line over pin or signal names)
Address on the memory map
: Lower address to the upper part, higher address to
the lower part
Note
: Explanation of Note in text
Caution
: Content to be read carefully
Remark
: Complementary explanation of text
Numeric notation
: Binary .............. ××××B or ××××
Decimal ........... ××××
Hexadecimal ... ××××H
Related Documents
The following documents are provided for 87AD series CMOS version products.
Numbers in the table are document numbers.
Document Name
Data Sheet
User's Manual
IC-1872
This manual
Application Note
Product Name
µPD78C10
µPD78C11
µPD78C10A
• (I)
Software fundamental
IC-2678
µPD78C11A
IEM-1131
• (II)
µPD78C12A
Floating-point format
µPD78C14
IC-2417
operation package
µPD78C14A
IC-2565
IEM-1242
µPD78CG14
IC-2564
µPD78CP14
IC-2533
Hardware
µPD78C17
IC-2788
IEM-1240
µPD78C18
IC-2789
µPD78CP18
IC-3033
µPD78C10(A)
IC-2814
• (III)
µPD78C11(A)
µPD78C10A(A)
IC-2846
µPD78C11A(A)
µPD78C12A(A)
µPD78C14(A)
IC-2813
µPD78CP14(A)
IC-3068
µPD78C17(A)
IC-3127
µPD78C18(A)
µPD78CP18(A)
IC-3233
The contents of the above documents are subject to change without prior notification. Please check whether
requested documentation is the latest version.
87AD Series CMOS Version Development
Expanded ROM/RAM
capacity
Relative performance
On-chip pull-up
resistor
(Mask option)
µ PD78C14A
PROM
product
µ PD78C14
Expanded
ROM
capacity
µ PD78C12A
On-chip pull-up
resistor
(Mask option)
On-chip pull-up
Note
resistor
µ PD78C11Note
(Mask option)
µ PD78C10
(ROM-less
product)
µ PD7811H
µ PD7810H
(ROM-less
product)
µ PD78CP14
µ PD78C11A
µ PD78C10A
(ROM-less
product)
CMOS process, on-chip pull-up
resistors (Mask option)
Time of product release
Note µPD78C10 and 78C11 are maintenance products.
µ PD78C18
µ PD78CP18
(PROM product)
µ PD78C17
(ROM-less
product)
TABLE OF CONTENTS
CHAPTER 1 GENERAL DESCRIPTION ...........................................................................................
1.1
1.2
1
Features .............................................................................................................................
Ordering Information and Quality Grade .....................................................................
3
5
1.2.1
Ordering information ...........................................................................................................
5
1.2.2
Quality grade ........................................................................................................................
9
Pin Configurations (Top View) .......................................................................................
10
1.3.1
Shrink DIP, QUIP (straight) (37), QUIP (36) ........................................................................
10
1.3.2
QFP (1B/3BE), WQFN .........................................................................................................
13
1.3.3
QFP (AB8) ............................................................................................................................
15
1.3.4
QFJ .......................................................................................................................................
16
Block Diagram...................................................................................................................
Functional Comparison of 87AD Series CMOS Products ...........................................
Differences between 87AD Series CMOS and NMOS Products ................................
Differences between "Standard" and "Special" Quality Grade Products ...............
18
19
21
22
CHAPTER 2 PIN FUNCTIONS .........................................................................................................
23
1.3
1.4
1.5
1.6
1.7
2.1
2.2
Normal Operation Mode .................................................................................................
23
2.1.1
PA7 to PA0 (Port A) .............................................................................................................
23
2.1.2
PB7 to PB0 (Port B) .............................................................................................................
23
2.1.3
PC7 to PC0 (Port C) .............................................................................................................
23
2.1.4
PD7 to PD0 (Port D) ............................................................................................................
25
2.1.5
PF7 to PF0 (Port F) ..............................................................................................................
26
2.1.6
WR (Write strobe) ...............................................................................................................
27
2.1.7
RD (Read strobe) .................................................................................................................
27
2.1.8
ALE (Address latch enable) .................................................................................................
27
2.1.9
MODE0, MODE1 (Mode) ....................................................................................................
28
2.1.10
NMI (Non maskable interrupt) ............................................................................................
28
2.1.11
INT1 (Interrupt request) ......................................................................................................
28
2.1.12
AN7 to AN0 (Analog input) .................................................................................................
28
2.1.13
VAREF (Reference voltage) ....................................................................................................
28
2.1.14
AVDD (Analog VDD) ................................................................................................................
28
2.1.15
AVSS (Analog VSS) .................................................................................................................
29
2.1.16
STOP (Stop control input) ...................................................................................................
29
2.1.17
X1, X2 (Crystal) ....................................................................................................................
29
2.1.18
RESET (Reset) .....................................................................................................................
29
2.1.19
VDD ........................................................................................................................................
29
2.1.20
VSS ........................................................................................................................................
29
2.1.21
IC ..........................................................................................................................................
29
EPROM Mode ....................................................................................................................
30
2.2.1
A14 to A0 (Address) ............................................................................................................
30
2.2.2
O7 to O0 (Data) ...................................................................................................................
30
2.2.3
CE (Chip enable) ..................................................................................................................
30
–i–
2.2.4
OE (Output enable) ... .........................................................................................................
30
2.2.5
MODE1, MODE0 (Mode) ....................................................................................................
30
2.2.6
RESET (Reset) .....................................................................................................................
30
2.2.7
VPP ........................................................................................................................................
30
2.2.8
VDD ........................................................................................................................................
30
2.2.9
VSS ........................................................................................................................................
30
Pin Input/Output Circuits ................................................................................................
Pin Mask Options (µPD78C18/78C14A/78C12A/78C11A Only) .................................
Processing of Unused Pins .............................................................................................
31
37
37
CHAPTER 3 INTERNAL BLOCK FUNCTIONS ...............................................................................
39
2.3
2.4
2.5
3.1
3.2
3.3
3.4
3.5
Registers ............................................................................................................................
Mode Registers .................................................................................................................
Arithmetic Logical Unit (ALU) ........................................................................................
Program Status Word (PSW) ..........................................................................................
Memory ..............................................................................................................................
39
41
42
42
44
3.5.1
µPD78C18/78C17/78C14/78C14A/78C12A/78C11A/78C10A memory configuration ......
44
3.5.2
µPD78CP18/78CP14 memory configuration ......................................................................
52
Timers ................................................................................................................................
Timer/Event Counter .......................................................................................................
Serial Interface ..................................................................................................................
Analog/Digital Converter ................................................................................................
Interrupt Control ..............................................................................................................
Zero-Cross Detector .........................................................................................................
57
57
57
57
57
58
CHAPTER 4 PORT FUNCTIONS .....................................................................................................
61
3.6
3.7
3.8
3.9
3.10
3.11
4.1
4.2
4.3
4.4
4.5
4.6
Port A (PA7 to PA0) .........................................................................................................
Port B (PB7 to PB0) ..........................................................................................................
Port C (PC7 to PC0) ..........................................................................................................
Port D (PD7 to PD0) .........................................................................................................
Port F (PF7 to PF0) ...........................................................................................................
Operation of Arithmetic and Logical Operation Instruction Involving a Port and
Immediate Data ................................................................................................................
73
CHAPTER 5 TIMER FUNCTIONS ....................................................................................................
75
5.1
5.2
5.3
61
65
66
70
71
Timer Configuration .........................................................................................................
Timer Mode Register (TMM) ..........................................................................................
Timer Operations .............................................................................................................
75
77
79
CHAPTER 6 TIMER/EVENT COUNTER FUNCTIONS ...................................................................
81
6.1
6.2
Timer/Event Counter Configuration ..............................................................................
Mode Registers .................................................................................................................
81
85
6.2.1
Timer/event counter mode register (ETMM) .....................................................................
85
6.2.2
Timer/event counter output mode register (EOM) ............................................................
88
– ii –
6.3
Timer/Event Counter Operation ....................................................................................
90
6.3.1
Interval timer mode .............................................................................................................
90
6.3.2
Event counter mode ............................................................................................................
92
6.3.3
Frequency measurement mode ..........................................................................................
93
6.3.4
Pulse width measurement mode .......................................................................................
94
6.3.5
Programmable rectangular-wave output mode ..................................................................
95
6.3.6
Timer/event counter program examples ............................................................................
97
CHAPTER 7 SERIAL INTERFACE FUNCTIONS .............................................................................
107
7.1
7.2
7.3
Serial Interface Configuration ........................................................................................
Serial Mode Registers .....................................................................................................
107
109
7.2.1
Serial mode high register (SMH) ........................................................................................
109
7.2.2
Serial mode low register (SML) ..........................................................................................
112
7.2.3
Serial mode register initialization ........................................................................................
114
Serial Interface Operation ...............................................................................................
114
7.3.1
Asynchronous mode ............................................................................................................
114
7.3.2
Synchronous mode ..............................................................................................................
121
7.3.3
I/O interface mode ..............................................................................................................
123
7.3.4
Example of serial interface program ..................................................................................
127
CHAPTER 8 ANALOG/DIGITAL CONVERTER FUNCTIONS .......................................................
137
8.1
8.2
8.3
Analog/Digital Converter Configuration.......................................................................
A/D Channel Mode Register (ANM) ..............................................................................
Analog/Digital Converter Operation .............................................................................
137
140
142
8.3.1
Scan mode ...........................................................................................................................
142
8.3.2
Select mode .........................................................................................................................
143
8.3.3
A/D converter operation control method ...........................................................................
144
8.3.4
Input voltage and conversion results .................................................................................
145
8.3.5
Example of analog/digital converter program ....................................................................
146
CHAPTER 9 INTERRUPT CONTROL FUNCTIONS .......................................................................
153
9.1
9.2
9.3
9.4
9.5
9.6
9.7
Interrupt Control Circuit Configuration ........................................................................
External Interrupt Sampling ...........................................................................................
Non-Maskable Interrupt Operation ...............................................................................
Maskable Interrupt Operation ........................................................................................
Interrupt Operation by SOFTI Instruction ....................................................................
Interrupt Wait Time .........................................................................................................
Multiple Interrupts ...........................................................................................................
154
158
160
163
167
168
169
CHAPTER 10 CONTROL FUNCTIONS ...........................................................................................
171
10.1 Standby Functions ...........................................................................................................
171
10.1.1
HALT mode ..........................................................................................................................
171
10.1.2
HALT mode release .............................................................................................................
172
10.1.3
Software STOP mode .........................................................................................................
174
10.1.4
Software STOP mode release ............................................................................................
175
– iii –
10.1.5
Hardware STOP mode ........................................................................................................
177
10.1.6
Hardware STOP mode release ...........................................................................................
178
10.1.7
Low supply voltage data retention mode...........................................................................
179
10.2 Reset Functions ................................................................................................................
10.3 Clock Generation Circuit .................................................................................................
180
182
CHAPTER 11 EXTERNAL DEVICE ACCESSES AND TIMINGS ...................................................
187
11.1 µPD78C18/78C14/78C14A/78C12A/78C11A External Device Accesses ....................
187
11.1.1
Memory mapping register (MM) ........................................................................................
190
11.1.2
Example of memory expansion ..........................................................................................
192
11.1.3
Example of peripheral device connection ..........................................................................
194
11.2 µPD78C17/78C10A External Device Access ..................................................................
198
MM register setting ............................................................................................................
199
11.3 Timings ..............................................................................................................................
11.2.1
201
CHAPTER 12 PROM ACCESSES (µPD78CP18/78CP14 ONLY) ...................................................
203
CHAPTER 13 PROM WRITE AND VERIFY OPERATIONS (µPD78CP18/78CP14 ONLY) ..........
207
13.1
13.2
13.3
13.4
13.5
PROM Programming Operating Modes ........................................................................
PROM Writing Procedure ................................................................................................
PROM Reading Procedure ...............................................................................................
Erasure Procedure (Ceramic Package Products Only) ................................................
One-Time PROM Products Screening ...........................................................................
208
209
210
211
211
CHAPTER 14 INSTRUCTION SET ..................................................................................................
213
14.1 Operand Notation and Description Method ................................................................
14.2 Explanation of Operation Code Symbols .....................................................................
14.3 Instruction Address Addressing.....................................................................................
213
215
216
14.3.1
Register addressing .............................................................................................................
216
14.3.2
Immediate addressing .........................................................................................................
217
14.3.3
Direct addressing .................................................................................................................
218
14.3.4
Relative addressing .............................................................................................................
218
14.3.5
Extended relative addressing ..............................................................................................
219
14.4 Operand Address Addressing.........................................................................................
220
14.4.1
Register addressing .............................................................................................................
220
14.4.2
Register indirect addressing ...............................................................................................
222
14.4.3
Auto-increment addressing .................................................................................................
223
14.4.4
Auto-decrement addressing ................................................................................................
224
14.4.5
Double auto-increment addressing .....................................................................................
225
14.4.6
Base addressing ..................................................................................................................
226
14.4.7
Base index addressing ........................................................................................................
227
14.4.8
Working register addressing ...............................................................................................
228
14.4.9
Accumulator indirect addressing ........................................................................................
229
14.4.10 Immediate addressing .........................................................................................................
229
14.4.11 Extended immediate addressing ........................................................................................
230
14.4.12 Direct addressing .................................................................................................................
231
– iv –
14.5
14.6
Number of States Required for Skipping ...................................................................
Instruction Descriptions ................................................................................................
232
233
14.6.1
8-bit data transfer instructions .........................................................................................
233
14.6.2
16-bit data transfer instructions .......................................................................................
242
14.6.3
8-bit operation instructions (Register) .............................................................................
252
14.6.4
8-bit operation instructions (Memory) .............................................................................
263
14.6.5
Immediate data operation instructions ............................................................................
270
14.6.6
Working register operation instructions ..........................................................................
285
14.6.7
16-bit operation instructions ............................................................................................
294
14.6.8
Multiplication/division instructions ...................................................................................
300
14.6.9
Increment/decrement instructions ...................................................................................
301
14.6.10 Other operation instructions ............................................................................................
304
14.6.11 Rotation/shift instructions ................................................................................................
306
14.6.12 Jump instructions .............................................................................................................
313
14.6.13 Call instructions ................................................................................................................
316
14.6.14 Return instructions ...........................................................................................................
319
14.6.15 Skip instructions ...............................................................................................................
321
14.6.16 CPU control instructions ...................................................................................................
323
Stacked Instructions ......................................................................................................
326
CHAPTER 15 OPERATING PRECAUTIONS ...................................................................................
327
14.7
15.1
15.2
15.3
15.4
15.5
15.6
15.7
15.8
15.9
15.10
15.11
15.12
RAE Bit Setting...............................................................................................................
Port D/F Setting .............................................................................................................
Timer, Timer/Event Counter Compare Register Setting .........................................
Restrictions on Serial Interface and Asynchronous Modes ....................................
Serial Interface Start Bit Input .....................................................................................
Serial Interface and Transmission Format Change ..................................................
Input Voltage to Analog Input Pin ..............................................................................
Limitations on Hardware STOP Mode ........................................................................
How to Use Standby Flag .............................................................................................
Bus Interface ...................................................................................................................
Restrictions on IE-78C11-M Operation........................................................................
Electrostatic Withstand Limit of VPP Pin ....................................................................
327
328
328
329
330
330
330
332
335
335
336
336
APPENDIX A INTROCUTION TO PIGGYBACK PRODUCT ..........................................................
337
A.1
Pin Functions ..................................................................................................................
340
A.1.1
Lower pins (µPD78C11A/78C12A/78C14 QUIP type compatible) .................................
340
A.1.2
Upper pins (27C256/27C256A compatible) .....................................................................
342
Memory Configuration ..................................................................................................
Memory Mapping Register (MM) ................................................................................
Interface with EPROM ...................................................................................................
342
346
348
APPENDIX B DEVELOPMENT TOOLS...........................................................................................
349
APPENDIX C INDEX OF INSTRUCTIONS (ALPHABETICAL ORDER) ........................................
353
A.2
A.3
A.4
–v–
[MEMO]
– vi –
LIST OF FIGURES (1/3)
Figure No.
Title
Page
3-1
3-2
3-3
3-4
3-5
3-6
3-7
3-8
3-9
3-10
3-11
3-12
3-13
3-14
3-15
Register Configuration ...........................................................................................................
PSW Configuration ................................................................................................................
Memory Map (µPD78C18) .....................................................................................................
Memory Map (µPD78C17) .....................................................................................................
Memory Map (µPD78C14/78C14A) .......................................................................................
Memory Map (µPD78C12A) ..................................................................................................
Memory Map (µPD78C11A) ..................................................................................................
Memory Map (µPD78C10A) ..................................................................................................
Memory Map (µPD78C18 Mode) ..........................................................................................
Memory Map (µPD78C14 Mode) ..........................................................................................
Memory Map (µPD78C12A Mode) ........................................................................................
Memory Map (µPD78C11A Mode) ........................................................................................
Zero-Cross Detector ..............................................................................................................
Zero-Cross Detection Signal ..................................................................................................
Zero-Cross Mode Register Format ........................................................................................
39
42
46
47
48
49
50
51
53
54
55
56
58
58
59
4-1
4-2
4-3
4-4
4-5
4-6
4-7
4-8
4-9
4-10
Port A .....................................................................................................................................
Mode A Register Format .......................................................................................................
Port A Specified as Output Port .............................................................................................
Port A Specified as Input Port ................................................................................................
Mode B Register Format .......................................................................................................
Mode Control C Register Format ...........................................................................................
Mode C Register Format .......................................................................................................
Port C Specified as Control Signal Output .............................................................................
Port C Specified as Control Signal Input ................................................................................
Mode F Register Format .......................................................................................................
61
61
62
62
65
66
67
68
68
71
5-1
5-2
Timer Block Diagram .............................................................................................................
Timer Mode Register (TMM) Format .....................................................................................
76
78
6-1
6-2
6-3
6-4
6-5
6-6
6-7
6-8
6-9
6-10
6-11
6-12
6-13
6-14
6-15
Timer/Event Counter Block Diagram .....................................................................................
Timer/Event Counter Mode Register Format ........................................................................
Output Control Circuit Block Diagram (CO0 Output) .............................................................
Timer/Event Counter Output Mode Register Format ............................................................
Timer/Event Counter Setting Procedure ................................................................................
Timer/Event Counter Mode Register Setting (Interval Timer Mode) .....................................
Interval Timer Mode Operation ..............................................................................................
Timer/Event Counter Mode Register Setting (Event Counter Mode) ....................................
Event Counter Mode Operation .............................................................................................
Timer/Event Counter Mode Register Setting (Frequency Measurement Mode) ...................
Frequency Measurement Mode Operation ...........................................................................
Timer/Event Counter Mode Register Setting (Pulse Width Measurement Mode) ................
Pulse Width Measurement Mode Operation ........................................................................
Timer/Event Counter Output Mode Register Setting ............................................................
Timer/Event Counter Mode Register Setting (Programmable Rectangular-Wave
Output Mode) ........................................................................................................................
Programmable Rectangular-Wave Output Mode Operation ..................................................
Timer/Event Counter Mode Register Setting (Programmable Rectangular-Wave Output:
ECNT Clear, CO0 Output Reset) ...........................................................................................
Port C Setting (Programmable Rectangular-Wave Output) ....................................................
Timer/Event Counter Mode Register Setting (Programmable Rectangular-Wave Output:
ECNT Operation Setting) .......................................................................................................
Single Pulse Output ...............................................................................................................
Port C Setting (Single Pulse Output) .....................................................................................
Interrupt Mask Register Setting (Single Pulse Output: INTEIN Mask Release) ....................
Timer/Event Counter Mode Register Setting (Single Pulse Output: ECNT
Operation Setting) ..................................................................................................................
81
87
88
89
90
91
91
92
92
93
93
94
95
95
6-16
6-17
6-18
6-19
6-20
6-21
6-22
6-23
– vii –
96
96
98
98
99
100
101
101
102
LIST OF FIGURES (2/3)
Figure No.
6-24
Title
Page
6-25
Timer/Event Counter Mode Register Setting (Single Pulse Output: CO0 Output
Timing Setting) .......................................................................................................................
Interrupt Mask Register (MKL) Setting (Single Pulse Output: INTE1 Mask Release) ...........
103
104
7-1
7-2
7-3
7-4
7-5
7-6
7-7
7-8
7-9
7-10
7-11
7-12
7-13
7-14
7-15
7-16
Serial Interface Configuration ................................................................................................
Serial Mode High Register (SMH) Format .............................................................................
Serial Mode Low Register (SML) Format ..............................................................................
Serial Mode Register Format in Asynchronous Mode ...........................................................
Asynchronous Data Format ...................................................................................................
Serial Mode Register Format in Synchronous Mode .............................................................
Synchronous Mode Timing ....................................................................................................
Serial Mode Register Format in I/O Interface Mode ..............................................................
I/O Interface Mode Timing .....................................................................................................
Example of Serial Data Transfer System Configuration .........................................................
Serial Mode Register Setting .................................................................................................
Timer Mode Register Setting ................................................................................................
Port C Setting (Serial Interface) .............................................................................................
Serial Mode High Register (SMH) Setting (Serial Interface: Transmission Enable) ..............
Interrupt Mask Register (MKH) Setting (Serial Interface: INTSR Mask Release) .................
Serial Mode High Register (SMH) Setting (Serial Interface: Reception Enable) ...................
107
111
113
115
118
121
122
123
124
127
128
129
130
130
133
133
8-1
8-2
8-3
8-4
8-5
8-6
8-7
8-8
8-9
A/D Converter Block Diagram ................................................................................................
A/D Channel Mode Register Format .....................................................................................
A/D Channel Mode Register in Scan Mode ...........................................................................
Outline of A/D Converter Operation Timing in Scan Mode ....................................................
A/D Channel Mode Register in Select Mode .........................................................................
Outline of A/D Converter Operation Timing in Select Mode .................................................
Relationship Between Analog Input Voltage and A/D Conversion Results ............................
Memory Map (Store Example of A/D Conversion Result) .....................................................
A/D Channel Mode Register Settings ....................................................................................
138
141
142
143
143
144
145
146
147
9-1
9-2
9-3
9-4
9-5
9-6
9-7
9-8
Interrupt Control Circuit Block Diagram .................................................................................
Mask Register (MKL, MKH) Format ......................................................................................
Interrupt Sampling .................................................................................................................
Interrupt Operation Procedure ...............................................................................................
Internal Configuration of NMI Pin ..........................................................................................
Interrupt Servicing Sequence (Masking released for both INT1 and INT2) ............................
Interrupt Servicing Sequence (Masking released for either INT1 or INT2) ............................
3-Level Multiple Interrupts .....................................................................................................
154
156
159
161
162
164
165
169
10-1
10-2
10-3
10-4
10-5
10-6
10-7
10-8
10-9
10-10
10-11
10-12
10-13
HALT Mode Release Timing (RESET Signal Input) ................................................................
HALT Mode Release Timing (In EI State) ..............................................................................
HALT Mode Release Timing (In DI State) ..............................................................................
Software STOP Mode Release Timing (RESET Signal Input) ................................................
SB Flag Operation ..................................................................................................................
Software STOP Mode Release Timing (NMI Signal Input) ....................................................
Hardware STOP Mode Release Timing (STOP Signal Input) .................................................
Hardware STOP Mode Release Timing (RESET Signal Input) ...............................................
Hardware STOP Mode Release Timing (STOP Signal Rising to RESET Signal Input) ...........
Relation between VDD and SB Flag ........................................................................................
Oscillator Connection Circuit .................................................................................................
Example of External Clock Input Circuit .................................................................................
Examples of Poor Resonator Connection Circuit ...................................................................
172
173
173
175
176
176
178
178
179
179
182
182
183
– viii –
LIST OF FIGURES (3/3)
Figure No.
Title
Page
11-1
11-2
11-3
11-4
11-5
11-6
11-7
11-8
11-9
11-10
11-11
11-12
11-13
11-14
11-15
External Expansion Modes Set by Memory Mapping Register .............................................
Memory Mapping Register Format (µPD78C18/78C14/78C14A/78C12A/78C11A) ..............
Example of Memory Expansion (Reference Diagram) ...........................................................
Memory Mapping Register Settings .....................................................................................
µPD71055 Connection Diagram (Reference Diagram) ..........................................................
Memory Map (µPD78C18) .....................................................................................................
Memory Map (µPD78C14/78C14A) .......................................................................................
Memory map (µPD78C12A) ..................................................................................................
Memory Map (µPD78C11A) ..................................................................................................
MM Register Format (µPD78C17/78C10A) ...........................................................................
µPD78C17 Address Space ....................................................................................................
µPD78C10A Address Space ..................................................................................................
OP Code Fetch Timing ...........................................................................................................
External Device Read Timing .................................................................................................
External Device Write Timing ................................................................................................
189
191
192
193
195
196
196
197
197
199
199
200
202
202
202
12-1
12-2
Memory Mapping Register Format (µPD78CP18) .................................................................
Memory Mapping Register Format (µPD78CP14) .................................................................
204
205
13-1
13-2
PROM Write/Verify Timing ....................................................................................................
PROM Read Timing ...............................................................................................................
209
210
15-1
15-2
15-3
15-4
15-5
15-6
Analog Input Circuit Block Diagram .......................................................................................
When Both NMI and STOP Are Used ....................................................................................
Control Timing of NMI and STOP ..........................................................................................
When Both NMI and STOP Are Used ....................................................................................
Control Timing of RESET and STOP ......................................................................................
µPD78C18 Read Operation ...................................................................................................
331
332
333
334
334
335
A-1
A-2
A-3
A-4
A-5
Memory Map (µPD78C14 Mode) ..........................................................................................
Memory Map (µPD78C12A Mode) ........................................................................................
Memory Map (µPD78C11A Mode) ........................................................................................
Memory Mapping Register Format (µPD78CG14) ................................................................
Connection to 27C256A .........................................................................................................
343
344
345
347
348
– ix –
[MEMO]
–x–
LIST OF TABLES
Table No.
Title
Page
2-1
2-2
2-3
2-4
2-5
Operation of PC7 to PC0 .......................................................................................................
Operation of PF7 to PF0 (µPD78C18/78C14/78C14A/78C12A/78C11A/78CP18/78CP14) ....
Operation of PF7 to PF0 (µPD78C17/78C10A) ......................................................................
MODE0 and MODE1 Functions (µPD78C17/78C10A) ..........................................................
Pin Type No. ..........................................................................................................................
24
26
27
28
31
3-1
3-2
Mode Register Functions ......................................................................................................
Flag Operations ......................................................................................................................
41
43
4-1
4-2
4-3
4-4
Operation of PD7 to PD0 (µPD78C18/78C14/78C14A/78C12A/78C11A/78CP18/78CP14) ...
Operation of PF7 to PF0 (µPD78C18/78C14/78C14A/78C12A/78C11A/78CP18/78CP14) ....
Operation of PF7 to PF0 (µPD78C17/78C10A) ......................................................................
Operation of Arithmetic/Logical Operation Instructions Involving a Port ...............................
70
72
72
73
6-1
6-2
6-3
6-4
Timing for Latching in ECPT ..................................................................................................
ECNT Inputs ..........................................................................................................................
ECNT Clearing ........................................................................................................................
INTEIN Interrupt Request Flag Setting ..................................................................................
82
83
84
84
7-1
7-2
7-3
Timer Setting .........................................................................................................................
Maximum Data Transfer Rate at Transmission .....................................................................
Maximum Data Transfer Rate at Reception ..........................................................................
118
119
120
8-1
Conversion Speed Settings ...................................................................................................
140
9-1
9-2
Priorities and Interrupt Addresses .........................................................................................
Maximum Interrupt Wait Time ..............................................................................................
153
168
10-1
10-2
10-3
10-4
10-5
Output Pin Statuses ...............................................................................................................
Output Pin Statuses ...............................................................................................................
Hardware States after Reset .................................................................................................
Pin States after Reset ............................................................................................................
Recommended Ceramic Resonator .......................................................................................
171
174
180
181
185
11-1
PF7 to PF0 Address Bus Selection ........................................................................................
187
13-1
13-2
13-3
Pin Functions in PROM Programming ...................................................................................
PROM Programming Modes .................................................................................................
Recommended Connection of Unused Pins (In PROM Programming Mode) .......................
207
208
208
15-1
Compare Register, Match Signal and Match Interrupt of Each Timer ...................................
328
– xi –
CHAPTER 1 GENERAL DESCRIPTION
CMOS version products in the 87AD series have the following functions integrated in a single chip:
•
ROM (except µPD78C17, 78C10A)
•
RAM
•
16-bit ALU
•
A/D converter
•
Multi-function timers/event counters
•
General-purpose serial interface, etc.
87AD series CMOS products offer enhanced standby functions and a wide range of packages while maintaining
compatibility with existing NMOS products. This allows further reductions in system low power consumption and
size to be achieved.
The features of the various products are shown below.
Product Name
µPD78C10A
On-Chip ROM
On-Chip RAM
External Expansion Memory
Remarks
None
256 × 8 bits
Up to 64K bytes
ROM-less product
4K × 8 bits
256 × 8 bits
Up to 60K bytes
On-chip pull-up resistor
µPD78C10A(A)
µPD78C11A
µPD78C11A(A)
µPD78C12A
specifiable
8K × 8 bits
256 × 8 bits
Up to 56K bytes
µPD78C12A(A)
µPD78C14
On-chip pull-up resistor
specifiable
16K × 8 bits
256 × 8 bits
Up to 48K bytes
—
µPD78C14(A)
µPD78C14A
On-chip pull-up resistor
specifiable
µPD78CP14
PROM product
µPD78CP14(A)
µPD78CG14
µPD78C17
16K × 8 bits
(external)
Piggy-back product
None
1K × 8 bits
Up to 63K bytes
ROM-less product
32K × 8 bits
1K × 8 bits
Up to 31K bytes
On-chip pull-up resistor
µPD78C17(A)
µPD78C18
µPD78C18(A)
µPD78CP18
specifiable
PROM product
µPD78CP18(A)
1
CHAPTER 1
GENERAL DESCRIPTION
In the µPD78CP18/78CP14, the on-chip mask ROM of the µPD78C18/78C14 is replaced with one-time PROM
or EPROM.
One-time PROM products can be programmed once only, and are useful for short-run and multiple-device set
production and early start-up. EPROM products can be programmed and reprogrammed, and are ideally suited to
system evaluation.
The relationship between "Standard" quality grade products and "Special" quality grade products.
"Standard" Quality Grade Products
"Special" Quality Grade Products
µPD78C10A
µPD78C10A(A)
µPD78C11A
µPD78C11A(A)
µPD78C12A
µPD78C12A(A)
µPD78C14
µPD78C14(A)
µPD78CP14
µPD78CP14(A)
µPD78C17
µPD78C17(A)
µPD78C18
µPD78C18(A)
µPD78CP18
µPD78CP18(A)
Applications
• The "Standard" Products
• Stationary machine and OA equipment .... PPC (Plain paper copier), printer, electronic typewriter, ECR
(Electronic cash register), FAX, bar code reader, etc.
• Automobile equipment ............................... Automobile air conditioner, cellular phone (communication),
etc.
• Home electric appliances ........................... Air conditioner, VCRs, etc.
• Others ......................................................... Electronic musical instrument, POS (Point of sales terminal),
inverter, electronic sewing machine, auto focus cameras, etc.
• The "Special" Products
• Automobile equipment ............................... Automobile electronic equipment, fuel control
2
CHAPTER 1
GENERAL DESCRIPTION
1.1 Features
• 159 types of instructions
• Multiplication/division instructions, 16-bit operation instructions possible
• Minimum instruction execution time
• 0.8 µs (at 15 MHz operation)
• ROM capacity
• 32768 × 8 bits (µPD78C18/78CP18Note 1)
• 16384 × 8 bits (µPD78C14, 78C14A, 78CP14Note 1)
•
8192 × 8 bits (µPD78C12A)
•
4096 × 8 bits (µPD78C11A)
• ROM-less
(µPD78C17/78C10A)
• RAM capacityNote 2
•
•
1024 × 8 bits (µPD78C18/78CP18/78C17)
256 × 8 bits (µPD78C14/78C14A/78CP14/78C12A/78C11A/78C10A)
• 8-bit resolution A/D converter
• 8 channels
• General-purpose serial interface
• Asynchronous mode
• Synchronous mode
• I/O interface mode
• 16-bit timer/event counter
• 1 channel
• 8-bit timer
• 2 channels
• Interrupt functions (3 external, 8 internal)
• Non-maskable interrupt :
1
• Maskable interrupts
10
:
• 6 priority levels, 6 interrupt addresses
Notes 1.
2.
µPD78CP18/78CP14 have on-chip one-time PROM or EPROM.
On-chip RAM can only be used when the RAE bit of the MM register is "1".
3
CHAPTER 1
GENERAL DESCRIPTION
• I/O lines
• Input/output ports : 40 (µPD78C18/78CP18/78C14/78C14A/78CP14/78C12A/78C11A)
: 28 (µPD78C17/78C10A)
• Edge-detected inputs : 4 inputs
• Zero-cross detection function
• Standby functions
• HALT mode
• Hardware/software STOP mode
• Incorporation of pull-up resistors can be specified bit wise for port A and port C.Note
• On-chip clock oscillator
• Wide variety of packages
Note µPD78C18/78C14A/78C12A/78C11A only.
4
CHAPTER 1
GENERAL DESCRIPTION
1.2 Ordering Information and Quality Grade
1.2.1 Ordering information
(1) µPD78C10A/78C10A(A)
Part number
Package
µPD78C10ACW
64-pin plastic shrink DIP
µPD78C10AGF-3BE
64-pin plastic QFP (resin thickness: 2.7 mm)
µPD78C10AGQ-36
64-pin plastic QUIP
µPD78C10AL
68-pin plastic QFJ
µPD78C10AGF(A)-3BE
64-pin plastic QFP (resin thickness: 2.7 mm)
µPD78C10AGQ(A)-36
64-pin plastic QUIP
µPD78C10AL(A)
68-pin plastic QFJ
(2) µPD78C11A/78C11A(A)
Part number
Package
µPD78C11ACW-×××
64-pin plastic shrink DIP
µPD78C11AGF-×××-3BE
64-pin plastic QFP (resin thickness: 2.7 mm)
µPD78C11AGQ-×××-36
64-pin plastic QUIP
µPD78C11AGQ-×××-37
64-pin plastic QUIP (straight)
µPD78C11AL-×××
68-pin plastic QFJ
µPD78C11AGF(A)-×××-3BE
64-pin plastic QFP (resin thickness: 2.7 mm)
µPD78C11AGQ(A)-×××-36
64-pin plastic QUIP
µPD78C11AL(A)-×××
68-pin plastic QFJ
Remark
××× indicates ROM code number.
5
CHAPTER 1
GENERAL DESCRIPTION
(3) µPD78C12A/78C12A(A)
Part number
µPD78C12ACW-×××
64-pin plastic shrink DIP
µPD78C12AGF-×××-3BE
64-pin plastic QFP (resin thickness: 2.7 mm)
µPD78C12AGQ-×××-36
64-pin plastic QUIP
µPD78C12AGQ-×××-37
64-pin plastic QUIP (straight)
µPD78C12AL-×××
68-pin plastic QFJ
µPD78C12AGF(A)-×××-3BE
64-pin plastic QFP (resin thickness: 2.7 mm)
µPD78C12AGQ(A)-×××-36
64-pin plastic QUIP
µPD78C12AL(A)-×××
68-pin plastic QFJ
Remark
6
Package
××× indicates ROM code number.
CHAPTER 1
GENERAL DESCRIPTION
(4) µPD78C14/78C14(A)/78C14A/78CG14/78CP14/78CP14(A)
Part number
Package
µPD78C14CW-×××
64-pin plastic shrink DIP
µPD78C14G-×××-36
64-pin plastic QUIP
µPD78C14G-×××-37
64-pin plastic QUIP (straight)
µPD78C14G-×××-1B
64-pin plastic QFP (resin thickness: 2.05 mm)
µPD78C14GF-×××-3BE
64-pin plastic QFP (resin thickness: 2.7 mm)
µPD78C14L-×××
68-pin plastic QFJ
µPD78C14G(A)-×××-36
64-pin plastic QUIP
µPD78C14GF(A)-×××-3BE
64-pin plastic QFP (resin thickness: 2.7mm)
µPD78C14L(A)-×××
68-pin plastic QFJ
µPD78C14AG-×××-AB8
64-pin plastic QFP (inter-pin pitch: 0.8 mm)
µPD78CG14E
64-pin ceramic piggyback QUIP
µPD78CP14CW
64-pin plastic shrink DIP
µPD78CP14DW
64-pin ceramic shrink DIP with window
µPD78CP14G-36
64-pin plastic QUIP
µPD78CP14GF-3BE
64-pin plastic QFP (resin thickness: 2.7 mm)
µPD78CP14KB
64-pin ceramic WQFN
µPD78CP14L
68-pin plastic QFJ
µPD78CP14R
64-pin ceramic QUIP with window
µPD78CP14G(A)-36
64-pin plastic QUIP
Remark
××× indicates ROM code number.
7
CHAPTER 1
GENERAL DESCRIPTION
(5) µPD78C17/78C17(A)
Part number
Package
µPD78C17CW
64-pin plastic shrink DIP
µPD78C17GF-3BE
64-pin plastic QFP (resin thickness: 2.7 mm)
µPD78C17GQ-36
64-pin plastic QUIP
µPD78C17GF(A)-3BE
64-pin plastic QFP (resin thickness: 2.7 mm)
µPD78C17GQ(A)-36
64-pin plastic QUIP
(6) µPD78C18/78C18(A)/78CP18/78CP18(A)
Part number
µPD78C18CW-×××
64-pin plastic shrink DIP
µPD78C18GF-×××-3BE
64-pin plastic QFP (resin thickness: 2.7 mm)
µPD78C18GQ-×××-36
64-pin plastic QUIP
µPD78C18GF(A)-×××-3BE
64-pin plastic QFP (resin thickness: 2.7 mm)
µPD78C18GQ(A)-×××-36
64-pin plastic QUIP
µPD78CP18CW
64-pin plastic shrink DIP
µPD78CP18DW
64-pin ceramic shrink DIP with window
µPD78CP18GF-3BE
64-pin plastic QFP (resin thickness: 2.7 mm)
µPD78CP18GQ-36
64-pin plastic QUIP
µPD78CP18KB
64-pin ceramic WQFN
µPD78CP18GF(A)-3BE
64-pin plastic QFP (resin thickness: 2.7 mm)
µPD78CP18GQ(A)-36
64-pin plastic QUIP
Remark
8
Package
××× indicates ROM code number.
CHAPTER 1
GENERAL DESCRIPTION
1.2.2 Quality grade
• Standard
µPD78C10A
µPD78C14A
µPD78C18
µPD78C11A
µPD78CG14
µPD78CP18
µPD78C12A
µPD78CP14
µPD78C14
µPD78C17
• Special
µPD78C10A(A)
µPD78C14(A)
µPD78C18(A)
µPD78C11A(A)
µPD78CP14(A)
µPD78CP18(A)
µPD78C12A(A)
µPD78C17(A)
Please refer to "Quality grade on NEC Semiconductor Devices" (Document number IEI-1209) published by NEC
Corporation to know the specification of quality grade on the devices and its recommended applications.
9
CHAPTER 1
GENERAL DESCRIPTION
1.3 Pin Configurations (Top View)
1.3.1 Shrink DIP, QUIP (straight) (37), QUIP (36)
(1) Normal operation mode
10
PA0
1
64
VDD
PA1
2
63
STOP
PA2
3
62
PD7
PA3
4
61
PD6
PA4
5
60
PD5
PA5
6
59
PD4
PA6
7
58
PD3
PA7
8
57
PD2
PB0
9
56
PD1
PB1
10
55
PD0
PB2
11
54
PF7
PB3
12
53
PF6
PB4
13
52
PF5
PB5
14
51
PF4
PB6
15
50
PF3
PB7
16
49
PF2
PC0/TXD
17
48
PF1
PC1/RXD
18
47
PF0
PC2/SCK
19
46
ALE
PC3/INT2
20
45
WR
PC4/TO
21
44
RD
PC5/CI
22
43
AVDD
PC6/CO0
23
42
VAREF
PC7/CO1
24
41
AN7
NMI
25
40
AN6
INT1
26
39
AN5
MODE1
27
38
AN4
RESET
28
37
AN3
MODE0
29
36
AN2
X2
30
35
AN1
X1
31
34
AN0
VSS
32
33
AVSS
CHAPTER 1
GENERAL DESCRIPTION
PA7 to PA0
: Port A
X1, X2
: Crystal
PB7 to PB0
: Port B
AN7 to AN0
: Analog Input
PC7 to PC0
: Port C
RD
: Read Strobe
PD7 to PD0
: Port D
WR
: Write Strobe
PF7 to PF0
: Port F
ALE
: Address Latch Enable
NMI
: Non Maskable Interrupt
RESET
: Reset
INT1
: Interrupt Request
VAREF
: Reference Voltage
MODE0, 1
: Mode0, 1
STOP
: Stop Control Input
11
CHAPTER 1
GENERAL DESCRIPTION
(2) EPROM mode (µPD78CP18/78CP14 only)
A0
1
64
VDD
A1
2
63
VPP
A2
3
62
O7
A3
4
61
O6
A4
5
60
O5
A5
6
59
O4
A6
7
58
O3
A7
8
57
O2
9
56
O1
10
55
O0
11
54
<2>
12
53
A14<3>
13
52
A13
14
51
A12
CE
15
50
A11
OE
16
49
A10
17
48
<2>
18
47
A8
19
46
20
45
21
44
22
43
23
42
24
41
A9
25
40
<1>
26
39
MODE1
27
38
<2>
<2>
RESET
28
37
MODE0
29
36
<2>
30
35
31
34
32
33
<1>
Cautions
<2>
<1>
<1>:
Connect directly to VSS.
<2>:
Pull down individually to VSS potential via a resistor.
<3>:
µPD78CP18 only.
In case of µPD78CP14, pull down to VSS potential via a resistor.
12
CHAPTER 1
GENERAL DESCRIPTION
1.3.2 QFP (1B/3BE), WQFN
PD3
PD4
PD5
PD6
PD7
STOP
VDD
PA0
PA1
PA2
PA3
PA4
PA5
(1) Normal operation mode
PA6
64 63 62 61 60 59 58 57 56 55 54 53 52
51
1
PD2
PA7
2
50
PD1
PB0
3
49
PD0
PB1
4
48
PF7
PB2
5
47
A14
PB3
6
46
PF5
PB4
7
45
PF4
PB5
8
44
PF3
PB6
9
43
PF2
PB7
10
42
PF1
PC0/TXD
11
41
PF0
PC1/RXD
12
40
ALE
PC2/SCK
13
39
WR
PC3/INT2
14
38
RD
PC4/TO
15
37
AVDD
PC5/CI
16
36
VAREF
PC6/CO0
17
35
AN7
PC7/CO1
18
34
AN6
NMI
19
33
AN5
AN4
AN3
AN2
AN1
AN0
AVSS
VSS
X1
X2
MODE0
RESET
MODE1
INT1
20 21 22 23 24 25 26 27 28 29 30 31 32
13
CHAPTER 1
GENERAL DESCRIPTION
O3
O4
O5
O6
O7
VPP
VDD
A0
A1
A2
A3
A4
A5
(2) EPROM mode (µPD78CP18/78CP14 only)
A6
64 63 62 61 60 59 58 57 56 55 54 53 52
51
1
O2
A7
2
50
O1
3
49
O0
4
48
<2>
5
47
A14 <3>
6
46
A13
7
45
A12
8
44
A11
CE
9
43
A10
OE
10
42
<2>
11
41
A8
12
40
13
39
14
38
15
37
16
36
17
35
18
34
19
33
<2>
<2>
A9
<2>
<1>
<1>
<2>
MODE0
RESET
<1>
Cautions
MODE1
20 21 22 23 24 25 26 27 28 29 30 31 32
<1>:
Connect directly to VSS.
<2>:
Pull down individually to VSS potential via a resistor.
<3>:
µPD78CP18 only.
In the case of µPD78CP14, pull down to VSS potential via a resistor.
14
CHAPTER 1
GENERAL DESCRIPTION
PA7
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
PC0/TXD
PC1/RXD
PC2/SCK
PC3/INT2
PC4/TO
PC5/CI
PC6/CO0
1.3.3 QFP (AB8)
PA1
X2
7
42
PA0
X1
8
41
VDD
VSS
9
40
STOP
AVSS
10
39
PD7
AN0
11
38
PD6
AN1
12
37
PD5
AN2
13
36
PD4
AN3
14
35
PD3
AN4
15
34
PD2
AN5
16
33
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
PD1
PD0
43
PF7
6
PF6
PA2
MODE0
PF5
44
PF4
5
PF3
PA3
RESET
PF2
45
PF1
4
PF0
PA4
MODE1
ALE
46
WR
3
RD
PA5
INT1
AVDD
47
VAREF
2
AN7
PA6
NMI
AN6
64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49
1
48
PC7/CO1
15
CHAPTER 1
GENERAL DESCRIPTION
1.3.4 QFJ
IC
PA6
PA5
PA4
PA3
PA2
PA1
PA0
VDD
STOP
PD7
PD6
PD5
PD4
PD3
PD2
IC
(1) Normal operation mode
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
9 8 7 6 5 4 3 2 1 68 67 66 65 64 63 62 61
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43
PC7/CO1
NMI
INT1
MODE1
RESET
MODE0
X2
X1
VSS
AVSS
AN0
AN1
AN2
AN3
AN4
AN5
AN6
PA7
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
PC0/TXD
PC1/RXD
PC2/SCK
PC3/INT2
IC
PC4/TO
PC5/IC
PC6/CO0
Remark IC: Internally connected
16
PD1
PD0
PF7
PF6
PF5
PF4
PF3
PF2
PF1
PF0
ALE
WR
RD
AVDD
IC
VAREF
AN7
CHAPTER 1
GENERAL DESCRIPTION
Open
A6
A5
A4
A3
A2
A1
A0
VDD
VPP
O7
O6
O5
O4
O3
O2
Open
(2) EPROM mode (µPD78CP14 only)
<2>
CE
OE
<2>
Open
9 8 7 6 5 4 3 2 1 68 67 66 65 64 63 62 61
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43
<2>
A9
<1>
MODE1
RESET
MODE0
<2>
<2>
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
Cautions
O1
O0
<2>
<2>
A13
A12
A11
A10
<2>
A8
<2>
<1>
Open
<1>
<1>
A7
Open : Leave open.
<1>
: Connect directly to VSS.
<2>
: Pull down individually to VSS potential via a resistor.
17
8
4
PC4/TO
PC5/CI
PC6/CO0
PC7/CO1
Timer/event
counter
8
Program
memory
(Depends
on product)
ALT
G. R
8
8
Internal data bus
16
16
6
Latch
Latch
PSW
8
8
8
INST. REG
INST.
decoder
ALU
(8/16)
16
Read/write
control
RD
PC7–0
PB7–0
PA7–0
8
16
8
Note Can only be used when the RAE bit of the MM
register is 1; when 0, external memory is
required.
8
PD7–0
AD7–0
8
16
A/D
converter
8
8
Data
Note
memory
(Depends
on product)
8
8
AN7–0 8
VAREF
AVDD
AVSS
8
8/16
Timer
8
8
16
Main
G. R
WR
System
control
ALE MODE1 MODE0 RESET
Standby
control
STOP
VDD
VSS
GENERAL DESCRIPTION
PC3/INT2/TI
8
8
PF7–0
AB15–8
CHAPTER 1
INT
control
INTI
Port F
NMI
8
Port D
Serial I/O
Port C
PC0/TXD
PC1/RXD
PC2/SCK
Port B
OSC
X2
8
Port A
X1
8
15
/
14
/
12
1.4 Block Diagram
18
16
Latch
INC/DEC
PC
SP
EA
V
A
B
C
D
E
H
L
EA'
V'
A'
B'
C'
D'
E'
H'
L'
Buffer
µPD78C10A
µPD78C11A
µPD78C12A
µPD78C14
µPD78C14A
Item
Instructions
159
0.8 µs (at 15 MHz operation)
Minimum instruction
execution time
On-chip ROM
ROM-less
4K × 8 bits
8K × 8 bits
256 × 8 bits
On-chip RAM
Interrupts
16K × 8 bits
External
3
Internal
8
8-bit timer × 2, 16-bit timer/event counter × 1
A/D converter
8 bit × 8 channels
Serial interface
UART (full duplex)/clocked
I/O
linesNote
• 64-pin plastic shrink
DIP (750 mil)
• 64-pin plastic QFP
(14 × 20 mm)
• 64-pin plastic QUIP
• 68-pin plastic QFJ
44
• 64-pin
• 64-pin
• 64-pin
• 64-pin
• 68-pin
plastic
plastic
plastic
plastic
plastic
shrink DIP (750 mil)
QFP (14 × 20 mm)
QUIP
QUIP (straight)
QFJ
• 64-pin plastic QFP
(14 × 14 mm)
(to be continued)
Note Incorporation of pull-up resistors can be specified by mask option for port A and port C of the µPD78C11A/78C12A.
GENERAL DESCRIPTION
Package
32
CHAPTER 1
Timer/counter
1.5 Functional Comparison of 87AD Series CMOS Products
Product Name
19
20
Product Name
µPD78CP14
µPD78CG14
µPD78C17
µPD78C18
µPD78CP18
32K × 8 bits
32K × 8 bits
(PROM)
Item
Instructions
159
0.8 µs (at 15 MHz operation)
Minimum instruction
execution time
16K × 8 bits
(PROM)
On-chip ROM
ROM-less
256 × 8 bits
On-chip RAM
Interrupts
16K × 8 bits
(piggyback)
1K × 8 bits
External
3
Internal
8
8-bit timer × 2, 16-bit timer/event counter × 1
A/D converter
8 bit × 8 channels
Serial interface
UART (full duplex)/clocked
I/O
linesNote
• 64-pin plastic shrink
DIP (750 mil)
• 64-pin plastic QFP
(14 × 20 mm)
• 64-pin plastic QUIP
• 68-pin plastic QFJ
• 64-pin ceramic shrink
DIP with window
(750 mil)
• 64-pin ceramic QUIP
with window
• 64-pin ceramic WQFN
32
• 64-pin ceramic piggyback
QUIP
• 64-pin plastic shrink DIP (750 mil)
• 64-pin plastic QFP (14 × 20 mm)
• 64-pin plastic QUIP
Note Incorporation of pull-up resistors can be specified by mask option for port A and port C of the µPD78C14A/78C18.
44
• 64-pin plastic shrink DIP
(750 mil)
• 64-pin plastic QFP
(14 × 20 mm)
• 64-pin plastic QUIP
• 64-pin ceramic shrink DIP
with window (750 mil)
• 64-pin ceramic WQFN
GENERAL DESCRIPTION
Package
44
CHAPTER 1
Timer/counter
CHAPTER 1
GENERAL DESCRIPTION
1.6 Differences between 87AD Series CMOS and NMOS Products
Process
CMOS
NMOS
Item
µPD78C18/78C17/78C14/78C14A/78C12A/
78C11A/78C10A
Product name
Instructions
µPD7811/7810
159 (STOP instruction added)
158
Special registers
28 (ZCM register added)
27
Standby function
3 modes: HALT mode, software STOP
mode, hardware STOP mode. On-chip
RAM data retained at low supply voltage
(2.5 V) in software/hardware STOP mode.
HLT instruction states
HALT mode
32-byte data of 256-byte on-chip RAM
retained at low supply voltage (3.2 V).
12
11
CPU operation
Stopped
M3, T2 cycle repetition
ALE
Low level
High level
Self-bias control of zero-cross
detector
Self-bias control possible (by ZCM register
specification)
Self-bias control not possible
NMI/RESET noise elimination
By analog delay
By clock sampling
Operation stoppable
(VAREF pin manipulation)
Operation not stoppable
method
A/D converter
Operation
RD/WR
during reset
Power
consumption
High impedance
High level
ALE
Output
PD/PF (ROM-less
products)
0 output to pin specified by address bus.
Remainder are high impedance.
Operating
65 mW Typ. (15 MHz)Note 1
750 mW Typ.
Standby
5 µW Typ.
4.8 mW Typ.
PackageNote 2
64-pin
64-pin
64-pin
64-pin
68-pin
Pin connection
VDD (pin 64)
VCC (pin 64)
(except QFP & QFJ)
STOP (pin 63)
VDD (pin 63)
Notes 1.
2.
plastic
plastic
plastic
plastic
plastic
shrink DIP
QUIP (straight)
QUIP
QFP (bent leads)
QFJ
64-pin plastic shrink DIP
64-pin plastic QUIP (straight)
64-pin plastic QUIP
80 mW (15 MHz) on the µPD78C18/78C17/78C14/78C14A.
Correspondence between pin connection and pin number depends on the type of package.
Caution There are also differences in electrical specifications, oscillator characteristics, and some internal
operation timings: These should be noted when directly replacing a µPD7811/7810 with a µPD78C18/
78C17/78C14/78C14A/78C12A/78C11A/78C10A.
21
Item
µPD78C10A,
µPD78C11A,
µPD78C12A
µPD78C14,
µPD78CP14
Quality grade
Special
Input leak current
AN7 to AN0; ± 10 µA (MAX.)
AN7 to AN0; ± 1 µA (MAX.)
plastic
plastic
plastic
plastic
plastic
shrink DIP
QUIP
QUIP (straight)Note 1
QFP
QFJ
Except µPD78C10/78C10A.
Except µPD78CP14(A).
µPD78C17(A),
µPD78C18(A),
µPD78CP18(A)
• 64-pin plastic shrink
DIP
• 64-pin plastic QFP
• 64-pin plastic QUIP
• 64-pin plastic QFP
• 64-pin plastic QUIP
• 68-pin plastic QFJ
• 64-pin plastic
QFPNote 2
• 64-pin plastic QUIP
• 68-pin plastic
QFJNote 2
• 64-pin plastic QFP
• 64-pin plastic QUIP
CHAPTER 1
2.
µPD78C14(A),
µPD78CP14(A)
Input leak current
• 64-pin
• 64-pin
• 64-pin
• 64-pin
• 68-pin
Notes 1.
µPD78C10A(A),
µPD78C11A(A),
µPD78C12A(A)
Standard
Electrical specifications
Package
µPD78C17,
µPD78C18
GENERAL DESCRIPTION
1.7 Differences between "Standard" and "Special" Quality Grade Products
22
Product Name
CHAPTER 2 PIN FUNCTIONS
The µPD78C18/78C17/78C14/78C14A/78C12A/78C11A/78C10A operate with normal operation mode pin functions.
µPD78CP18/78CP14 pin functions are of two kinds: Normal operation mode and EPROM mode. EPROM mode
is entered by driving the MODE1 pin low and the MODE0 pin high.
2.1 Normal Operation Mode
2.1.1 PA7 to PA0 (Port A) ... 3-state input/output
These are the 8-bit input/output pins of port A (8-bit input/output port with output latch), and can be specified bitwise as input/output by means of the Mode A register (MA).
Upon RESET input, PA7 to PA0 are set as input port (high-impedance). PA7 to PA0 also become high-impedance
in the hardware STOP mode.
In the µPD78C18/78C14A/78C12A/78C11A, pull-up resistors can be incorporated bit-wise.
2.1.2 PB7 to PB0 (Port B) ... 3-state input/output
These are the 8-bit input/output pins of port B (8-bit input/output port with output latch), and can be specified bitwise as input/output by means of the Mode B register (MB).
Upon RESET input, PB7 to PB0 are set as an input port (high-impedance). PB7 to PB0 also become high-impedance
in the hardware STOP mode.
In the µPD78C18/78C14A/78C12A/78C11A, pull-up resistors can be incorporated bit-wise.
2.1.3 PC7 to PC0 (Port C) ... 3-state input/output
These pins operate as the 8-bit input/output pins of port C (8-bit input/output port with output latch), but in addition
to functioning as an input/output port, they also function as pins for various control signals.
The PC7 to PC0 operating mode can be set bit-wise to port or control signal input/output mode by means of the
Mode Control C register (MCC) (see Table 2-1).
In the µPD78C18/78C14A/78C12A/78C11A, pull-up resistors can be incorporated bit-wise.
23
CHAPTER 2
PIN FUNCTIONS
Table 2-1. Operation of PC7 to PC0
MCCn=0
MCCn=1
Port Mode
Control Signal Input/Output Mode
PC0
Input/output port
TxD output
PC1
Input/output port
RxD input
PC2
Input/output port
SCK input/output
PC3
Input/output port
INT2/TI input
PC4
Input/output port
TO output
PC5
Input/output port
CI input
PC6
Input/output port
CO0 output
PC7
Input/output port
CO1 output
Remark n=0 to 7
(1) Port mode
When PC7 to PC0 are specified as input/output port by means of the mode control C register, they can be
set bit-wise as input or output port by means of the mode C register (MC).
(2) Control signal input/output mode
PC7 to PC0 can be set bit-wise as control pins by means of the mode control C register (MCC). The functions
of the various control pins are shown below.
(a) TxD (Transmit data) ... Output
The serial data transmission pin, from which the contents of the serial register are output.
(b) RxD (Receive data) ... Input
The serial data reception pin: Data on RxD is loaded into the serial register.
(c) SCK (Serial clock) ... Input/output
The serial input/output data control clock: Functions as an output when the internal clock is used, and
as an input when an external clock is used.
(d) INT2/TI (Interrupt request/Timer input) ... Input
The edge-triggered (falling edge) maskable interrupt input pin and timer external clock input pin. Can also
be used as the AC signal zero-cross detection pin.
Caution When pull-up resistors are incorporated in PC3 of the µPD78C18/78C14A/78C12A/78C11A,
the zero-cross function can not be operated correctly.
(e) TO (Timer output) ... Output
Outputs a square wave with the timer count time or one cycle of the internal clock (φ3) as a half-cycle.
(f) CI (Counter input) ... Input
The timer/event counter external pulse input.
(g) CO0, CO1 (Counter output) ... Output
These pins output a rectangular wave which is programmable by the timer/event counter.
Upon RESET input, PC7 to PC0 are set as input port (high-impedance). PC7 to PC0 also become high-impedance
in the hardware STOP mode.
24
CHAPTER 2
PIN FUNCTIONS
2.1.4 PD7 to PD0 (Port D) ... 3-state input/output
µPD78C18/78C14/78C14A/78C12A/78C11A/78CP18/78CP14
These are the 8-bit input/output pins of port D (8-bit input/output port with output latch), but in addition to
functioning as an input/output port, they also function as time-division address output and data input/output
(multiplexed address/data bus) pins for accessing externally expanded memory.
Pins PD7 to PD0 can be specified as shown below by setting the memory mapping register.
(1) Port mode
As port D input/output pins, PD7 to PD0 can be specified as input or output as a byte (8-bit) unit.
(2) Expansion mode
When an external device (program memory, data memory, or a peripheral device) is added in addition to onchip memory, PD7 to PD0 are used as a multiplexed address/data bus (AD7 to AD0). When an instruction
which references an external device is executed, the lower address information for the external device is
output in the first state of the external device reference machine cycle of that instruction, and the pins become
a bidirectional 8-bit data bus in the second and third states. At all other times, PD7 to PD0 are high-impedance.
Cautions
1. When pins PD7 to PD0 are functioning as an address/data bus, the contents of the
internal address bus are output as they are in synchronization with ALE in the first state
of all machine cycles.
2. Emulation cannot be performed by an emulator for a program which varies the port
D operating mode dynamically. Therefore, once the mode has been set, it should not
be changed to a different mode.
Upon RESET input, PD7 to PD0 are set as input port (high-impedance). PD7 to PD0 also become high-impedance
in the hardware STOP mode.
µPD78C17/78C10A
These pins function only as time-division address output and data input/output (multiplexed address/data bus) pins
for accessing externally installed memory.
The pins output the lower 8 bits of the memory address in the first state, and become a bidirectional 8-bit data
bus in the second and third states.
When the RESET signal is low, or when in the hardware STOP mode or a standby mode (HALT or STOP), PD7
to PD0 are high-impedance.
Caution Port D can only be used as an address/data bus.
25
CHAPTER 2
PIN FUNCTIONS
2.1.5 PF7 to PF0 (Port F) ... 3-state input/output
µPD78C18/78C14/78C14A/78C12A/78C11A/78CP18/78CP14
These are the 8-bit input/output pins of port F (8-bit input/output port with output latch), but in addition to
functioning as an input/output port, they also function as address outputs (AB15 to AB8) for accessing externally
expanded memory.
Pins PF7 to PF0 can be specified as shown below by setting the memory mapping register.
(1) Port mode
As port F input/output pins, PF7 to PF0 can be specified bit-wise as input or output by means of the mode
F register.
(2) Expansion mode
When an external device is expanded in addition to on-chip memory, PF7 to PF0 are used as an address bus
(AB15 to AB8) corresponding to the size of the external device, as shown in Table 2-2. When an instruction
which references an external device is executed, the upper address information for the external device is
output in the external device reference machine cycle of that instruction.
Caution Pins PF7 to PF0 set as an address bus have output to them the contents of the internal
address bus as they are in all machine cycles.
Pins not specified as address output pins are in port mode.
Caution Emulation cannot be performed by an emulator for a program which varies the port F
operating mode dynamically. Therefore, once the mode has been set, it should not be
changed to a different mode.
Table 2-2. Operation of PF7 to PF0 (µPD78C18/78C14/78C14A/78C12A/78C11A/78CP18/78CP14)
PF7
PF6
PF5
PF4
PF3
PF2
PF1
PF0
External Address Space
Port
Port
Port
Port
Port
Port
Port
Port
Up to 256 bytes
Port
Port
Port
Port
AB11
AB10
AB9
AB8
Up to 4K bytes
Port
Port
AB13
AB12
AB11
AB10
AB9
AB8
Up to 16K bytes
AB15
AB14
AB13
AB12
AB11
AB10
AB9
AB8
Up to 31K/48K/56K/60K bytesNote
Note 31K(µPD78C18), 48K (µPD78C14/78C14A), 56K (µPD78C12A), 60K (µPD78C11A)
The operation of the µPD78CP18 and 78CP14 differ depending on the setting of bits MM5 to MM7 of the
memory mapping register.
In the reset state (RESET input=low) or in the hardware STOP mode (STOP input=low), pins PF7 to PF0 become
high-impedance. When the RESET input or STOP input subsequently returns to the high level, they are set as address
bus or port according to the status of the MODE1 and MODE0 pins.
26
CHAPTER 2
PIN FUNCTIONS
µPD78C17/78C10A
These pins can be specified as an address bus (AB15 to AB8) corresponding to the size of the externally installed
device by means of the MODE0 and MODE1 pin settings, and the remaining pins can be used as general-purpose
input/output ports (see Table 2-3).
Table 2-3. Operation of PF7 to PF0 (µPD78C17/78C10A)
MODE1
MODE0
PF7
PF6
PF5
PF4
PF3
PF2
PF1
PF0
External Address Space
0
0
Port
Port
Port
Port
AB11
AB10
AB9
AB8
4K bytes
0
1
Port
Port
AB13
AB12
AB11
AB10
AB9
AB8
16K bytes
1
0
1
1
AB9
AB8
63K/64K bytesNote
Setting prohibited
AB15
AB14
AB13
AB12
AB11
AB10
Note 63K (µPD78C17), 64K (µPD78C10A)
In the reset state (RESET input=low) or in the hardware STOP mode (STOP input=low), pins PF7 to PF0 become
high-impedance. When the RESET input or STOP input subsequently returns to the high level, they are set as address
bus or port according to the status of the MODE1 and MODE0 pins.
Caution Emulation cannot be performed by an emulator for a program which varies the port F operating
mode dynamically. Therefore, once the mode has been set, it should not be changed to a different
mode.
2.1.6 WR (Write strobe) ... 3-state output
The strobe signal output for a write operation to external memory. This pin is driven high except in external memory
data write machine cycles. When the RESET signal is low or when in the hardware STOP mode, WR become highimpedance.
Remark
In a data write to internal RAM, WR is driven high.
2.1.7 RD (Read strobe) ... 3-state output
The strobe signal output for a read operation on external memory. This pin is driven high except in external memory
data read machine cycles. When the RESET signal is low or when in the hardware STOP mode, RD become highimpedance.
Remark
In a data read from internal ROM or RAM, RD is driven high.
2.1.8 ALE (Address latch enable) ... 3-state output
The strobe signal which externally latches the lower address information output to pins PD7 to PD0 for an access
to external memory. When the RESET signal is low or when in the hardware STOP mode, ALE is high-impedance.
Caution ALE output continues while the CPU is operating. Therefore, address latching by ALE is effective
external access machine cycles.
27
CHAPTER 2
PIN FUNCTIONS
2.1.9 MODE0, MODE1 (Mode) ... Input/output
µPD78C18/78C14/78C14A/78C12A/78C11A
The MODE0 pin is set to "0" (low level) and the MODE1 pin is set to "1" (high level) via a pull-up resistor. The
pull-up resistor R is 4 [kΩ] ≤ R ≤ 0.4 tCYC [kΩ] (tCYC unit is ns).
When the MODE0 pin is set to "0" (low level) and the MODE1 pin is not "1" (high level), on-chip ROM is not accessed
and these pins are functioned in the same way as those of the µPD78C17/78C10A.
µPD78C17/78C10A
The size of the externally installed memory can be selected as 4K bytes, 16K bytes, or 63K/64K bytes according
to the settings of the MODE0 and MODE1 pins.
Table 2-4. MODE0 and MODE1 Functions (µPD78C17/78C10A)
MODE1
MODE0
External Address Space
0
0
4K bytes (addresses 0000H to 0FFFH)
0
1Note 1
16K bytes (addresses 0000H to 3FFFH)
1
0
Setting prohibited
1Note 1
1Note 1
63K bytes (addresses 0000H to FBFFH)/ Note 2
64K bytes (addresses 0000H to FEFFH)
Notes 1. Pull-up resistor required.
The pull-up resistor R is 4 [kΩ] ≤ R ≤ 0.4 tCYC [kΩ] (tCYC unit is ns).
2. 63K (µPD78C17), 64K (µPD78C10A).
When the MODE0 and MODE1 pins are pulled high up to "1", a control signal is output in synchronization with
ALE.
The MODE0 and MODE1 input signals are sampled periodically and the mode is set.
Caution The µPD78CP18 and 78CP14 use the MODE0 pin for input and the MODE1 pin for input/output.
2.1.10 NMI (Non maskable interrupt) ... Input
The edge-triggered (falling edge) non maskable interrupt input.
2.1.11 INT1 (Interrupt request) ... Input
The edge-triggered (rising edge) maskable interrupt input. Can also be used as the AC input zero-cross detection
pin.
2.1.12 AN7 to AN0 (Analog input) ... Input
The 8 analog inputs to the A/D converter. AN7 to AN4 can also be used as input pins for falling edge detection;
when a falling edge is detected, the test flag is set (1).
2.1.13 VAREF (Reference voltage) ... Input
The A/D converter reference voltage input pin. Also used as the A/D converter operation control pin.
2.1.14 AVDD (Analog VDD)
The A/D converter power supply supply pin.
28
CHAPTER 2
PIN FUNCTIONS
2.1.15 AVSS (Analog VSS)
The A/D converter GND pin.
2.1.16 STOP (Stop control input)
The hardware STOP mode control pin; oscillation is stopped when this pin is driven low.
2.1.17 X1, X2 (Crystal)
Crystal connection pins for internal clock oscillation. When the clock is supplied from off chip, the clock should
be input to X1, and the inverted X1 clock to X2.
2.1.18 RESET (Reset) ... Input
The low-level active reset pin.
2.1.19 VDD
The positive power supply pin.
2.1.20 VSS
GND potential.
2.1.21 ICNote
Internally connected pin. Leave open.
Note QFJ package only.
29
CHAPTER 2
PIN FUNCTIONS
2.2 EPROM Mode
The EPROM mode can only be specified for the µPD78CP18/78CP14.
2.2.1 A14 to A0 (Address) ... Input
The 15-bit address input pins for an EPROM write/verify or read operation.
The on-chip EPROM of the µPD78CP14 is 16K bytes in size, and is therefore addressed by the lower 14 bits (A13
to A0). PF6 should be fixed low.
2.2.2 O7 to O0 (Data) ... Input/output
The 8-bit data input/output pins for an EPROM write/verify or read operation.
2.2.3 CE (Chip enable) ... Input
The Chip Enable signal input pin.
2.2.4 OE (Output enable) ... Input
The Output Enable signal input pin.
2.2.5 MODE1, MODE0 (Mode) ... Input
The MODE1 pin should be set to "0" (low level) and the MODE0 pin to "1" (high level).
2.2.6 RESET (Reset) ... Input
Should be set to "0" (low level).
2.2.7 VPP
The high-voltage application pin for an EPROM write/verify operation.
Inputs "1" (high level) in an EPROM read.
2.2.8 VDD
The power supply application pin.
2.2.9 VSS
The GND potential pin.
30
CHAPTER 2
PIN FUNCTIONS
2.3 Pin Input/Output Circuits
The input/output circuits for the pins are shown in partially simplified format in Table 2-5 and Figures (1) to (15).
Table 2-5. Pin Type No.
Type No.
Pin Name
µPD78C17/78C14/78C10A
µPD78C18/78C14A/
78C12A/78C11A
PA0 to PA7
5
5-A
PB0 to PB7
5
5-A
PC0, PC1
5
5-A
PC2/SCK
8
8-A
PC3/INT2
10
10-A
PC4 to PC7
5
5-A
PD0 to PD7
5
PF0 to PF7
5
NMI
2
INT1
9
RESET
2
RD
4
WR
4
ALE
4
STOP
2
MODE0
11
MODE1
11
AN0 to AN3
7
AN4 to AN7
12
VAREF
13
31
CHAPTER 2
PIN FUNCTIONS
(1) Type 1
VDD
P-ch
IN
N-ch
(2) Type 2
IN
(3) Type 4
VDD
Output data
P-ch
OUT
Output disable
32
N-ch
CHAPTER 2
PIN FUNCTIONS
(4) Type 4-A
VDD
Output data
P-ch
Mask option
OUT
N-ch
Output disable
(5) Type 5
Output data
IN/OUT
Type 4
Output disable
Type 1
(6) Type 5-A
Output data
IN/OUT
Type 4-A
Output disable
Type 1
(7) Type 7
AVDD
P-ch
IN
+
N-ch
–
AVDD
Sampling
C
AVSS
AVSS
Reference voltage
(From voltage tap of series
resistance string)
33
CHAPTER 2
PIN FUNCTIONS
(8) Type 8
Output data
Output disable
Type 5
IN/OUT
N-ch
N-ch
Type 2
MCC
(9) Type 8-A
Output data
Output disable
Type 5-A
IN/OUT
N-ch
N-ch
Type 2
MCC
(10) Type 9
Self-bias circuit
enable
IN
Type 1
34
Data
CHAPTER 2
PIN FUNCTIONS
(11) Type 10
Output data
Output disable
Type 5
IN/OUT
N-ch
Self-bias
circuit
enable
N-ch
Type 9
MCC
(12) Type 10-A
Output data
Output disable
Type 5-A
IN/OUT
N-ch
Self bias
circuit
enable
N-ch
Type 9
MCC
35
CHAPTER 2
PIN FUNCTIONS
(13) Type 11
IN/OUT
Output data
N-ch
Type 1
(14) Type 12
Type 7
IN
Type 2
Edge detector
(15) Type 13
Type 1
IN
STOP mode
P-ch
AVSS
36
CHAPTER 2
PIN FUNCTIONS
2.4 Pin Mask Options (µPD78C18/78C14A/78C12A/78C11A Only)
The following mask options are available for pins, and these can be selected bit-wise to suit the purpose.
Pin Name
Mask Option
PA7 to PA0
<1> Pull-up resistor incorporated
PB7 to PB0
<2> Pull-up resistor not incorporated
PC7 to PC0
Caution If a pull-up resistor is incorporated in PC3, the zero-cross function cannot be operated correctly.
2.5 Processing of Unused Pins
Pin
PA0
PB0
PC0
PD0
PF0
to
to
to
to
to
Recommended Connection
PA7
PB7
PC7
PD7
PF7
RD
WR
ALE
STOP
INT1, NMI
Connect to VSS or VDD via a resistor.
Leave open.
VDD
Connect to VSS or VDD.
AVDD
Connect to VDD.
VAREF
AVSS
Connect to VSS.
AN0 to AN7
Connect to AVSS or AVDD.
37
[MEMO]
38
CHAPTER 3 INTERNAL BLOCK FUNCTIONS
3.1 Registers
The central registers are the sixteen 8-bit registers, four 16-bit registers and special registers shown in Figure 3-1.
Figure 3-1. Register Configuration
15
0
PC
SP
15
0
EA
7
0
07
V
A
B
D
C
E
H
L
15
Main
0
EA'
7
0
07
V'
A'
B'
D'
C'
E'
H'
L'
ALT
(1) Accumulator (A)
Since an accumulator type architecture is used, data processing such as 8-bit arithmetic and logical operation
instructions centers on this accumulator.
This accumulator can be replaced with the ALT register paired with the vector register (V) by means of the
EXA instruction.
(2) Expansion accumulator (EA)
Data processing such as 16-bit arithmetic and logical operation instructions centers on this accumulator.
This accumulator can be replaced with the ALT register EA' by means of the EXA instruction.
39
CHAPTER 3
INTERNAL BLOCK FUNCTIOS
(3) Working register vector register (V)
When a working area is set in the memory space, the high-order 8 bits of the memory address are selected
using the V register and the low-order 8 bits are addressed by the immediate data in the instruction. Thus,
the memory area specified with the V register can be used as working registers with a 256 × 8-bit configuration.
Because a working register can be specified with a 1-byte address field, program reduction is possible by
using the working area for software flags, parameters and counters. The V register can be replaced with the
ALT register paired with an accumulator by means of the EXA instruction.
(4) General registers (B, C, D, E, H, L)
There are two sets of general registers (main: B, C, D, E, H, L; ALT: B', C', D', E', H', L'). They function
as auxiliary registers for the accumulator, and have a data pointer function as register pairs (BC, DE, HL; B'C',
D'E', H'L'). Four register pairs, DE, D'E', HL and H'L' in particular, have a base register function.
When the two sets are used, if an interrupt occurs in one set, the register contents are saved into the other
register set without saving them into the memory so that interrupt servicing can be carried out. The other
set of registers can also be used as a data pointer expansion registers. Single-step auto-increment/decrement
modes and a two-step auto-increment addressing mode are available for the register pairs, DE, HL, D'E' and
H'L', so that the processing time can be reduced. BC, DE and HL can be simultaneously replaced with the
ALT register by means of the EXX instruction. The HL register can be independently replaced with the ALT
register by means of the EXH instruction.
(5) Program counter (PC)
This is a 16-bit register which holds information on the next program address to be executed. This register
is normally incremented automatically according to the number of bytes of the instruction to be fetched. When
an instruction associated with a branch is executed, immediate data or register contents are loaded. RESET
input clears this counter to 0000H.
(6) Stack pointer (SP)
This is a 16-bit register which holds the start address of the memory stack area (LIFO format).
SP contents are decremented when a call or PUSH instruction is executed or an interrupt is generated, and
incremented when a return or POP instruction is executed.
40
CHAPTER 3
INTERNAL BLOCK FUNCTIONS
3.2 Mode Registers
Mode registers are provided (see Table 3-1) to control the ports, timers, timer/event counters, serial interface,
A/D converter and interrupt control blocks.
Table 3-1. Mode Register Functions
Mode Register Name
Read/
Write
MA
Mode A register
W
Performs bit-wise input/output specification for port A.
MB
Mode B register
W
Performs bit-wise input/output specification for port B.
MCC
Mode control C register
W
Performs bit-wise port/control mode specification for port C.
MC
Mode C register
W
Performs bit-wise input/output specification for port C when
in port mode.
MM
Memory mapping register
W
Performs port/expansion mode specification for port D and
port F.
MF
Mode F register
W
Performs bit-wise input/output specification for port F when in
port mode.
TMM
Timer mode register
ETMM
Timer/event counter mode
register
W
EOM
Timer/event counter output
mode register
R/W
SML
Serial mode register
SMH
MKL
R/W
W
Function
Specifies timer operating mode.
Specifies timer/event counter operating mode.
Controls CO0 and CO1 output level.
Specifies serial interface operating mode.
R/W
Interrupt mask register
R/W
Specifies interrupt request enable/disable.
ANM
A/D channel mode register
R/W
Specifies A/D converter operating mode.
ZCM
Zero-cross mode register
W
Specifies zero-cross detector operation.
MKH
41
CHAPTER 3
INTERNAL BLOCK FUNCTIOS
3.3 Arithmetic Logical Unit (ALU)
The ALU executes data processing such as 8-bit arithmetic and logical operations, shift and rotation, data
processing such as 16-bit arithmetic and logical operations and shift operations, 8-bit multiplication and 16-bit by 8bit division.
3.4 Program Status Word (PSW)
This word consists of 6 types of flags which are set/reset according to instruction execution results. Three of
these flags (Z, HC and CY) can be tested by an instruction. PSW contents are automatically saved to the stack when
an interrupt (external, internal or SOFTI instruction) is generated, and restored by the RETI instruction. RESET input
resets all bits to (0).
Figure 3-2. PSW Configuration
7
6
5
4
3
2
1
0
0
Z
SK
HC
L1
L0
0
CY
(1) Z (Zero)
When the operation result is zero, this flag is set (1). In all other cases, it is reset (0).
(2) SK (Skip)
When the skip condition is satisfied, this flag is set (1). If the condition is not satisfied, it is reset (0).
(3) HC (Half carry)
If an operation generates a carry out of bit 3 or a borrow into bit 3, this flag is set (1). In all other cases, it
is reset (0).
(4) L1
When MVI A, byte instructions are stacked, this flag is set (1). In all other cases, it is reset (0).
(5) L0
When MVI L, byte ; LXI H, word instructions are stacked, this flag is set (1). In all other cases, it is reset (0).
(6) CY (Carry)
When an operation generates a carry out of or a borrow into bit 7 or 15, this flag is set (1). In all other cases,
it is reset (0).
When one of 35 types of ALU instructions, a rotation instruction or a carry manipulation instruction is executed,
various flags are affected as shown in Table 3-2.
42
CHAPTER 3
INTERNAL BLOCK FUNCTIONS
Table 3-2. Flag Operations
Operation
reg, memory
immediate
skip
D6
D5
D4
D3
D2
D0
Z
SK
HC
L1
L0
CY
↕
0
↕
0
0
↕
↕
0
●
0
0
●
↕
↕
↕
0
0
↕
ADD
ADC
SUB
SBB
DADD
DADC
DSUB
DSBB
EADD
ESUB
ADDW
ADCW
SUBW
SBBW
ADDX
ADCX
SUBX
SBBX
ADI
ACI
SUI
SBI
ANA
ORA
XRA
DAN
DOR
DXR
ANAW
ORAW
XRAW
ANAX
ORAX
XRAX
ANI
ORI
XRI
ADDNC
SUBNB
GTA
LTA
DADDNC
DSUBNB
DGT
DLT
ADDNCW
SUBNBW
GTAW
LTAW
ADDNCX
SUBNBX
GTAX
LTAX
ADINC
SUINB
GTI
LTI
GTIW
LTIW
ONA
OFFA
DON
DOFF
ONAW
OFFAW
ONAX
OFFAX
ONI
OFFI
ONIW
OFFIW
↕
↕
●
0
0
●
NEA
EQA
DNE
DEQ
NEAW
EQAW
NEAX
EQAX
NEI
EQI
NEIW
EQIW
↕
↕
↕
0
0
↕
INR
DCR
INRW
DCRW
↕
↕
↕
0
0
●
DAA
↕
0
↕
0
0
↕
RLR RLL SLR SLL
DRLR DRLL DSLR DSLL
●
0
●
0
0
↕
SLRC SLLC
●
↕
●
0
0
↕
STC
●
0
●
0
0
1
CLC
●
0
●
0
0
0
MVI A, byte
●
0
●
1
0
●
MVI L, byte
LXI H, word
●
0
●
0
1
●
BIT
SK
SKN
SKIT
SKNIT
●
↕
●
0
0
●
RETS
●
1
●
0
0
●
●
0
●
0
0
●
ANIW
ORIW
All other instructions
↕ ... Affected (set or reset)
1 ... Set
0 ... Reset
● ... Not affected
43
CHAPTER 3
INTERNAL BLOCK FUNCTIOS
3.5 Memory
3.5.1 µPD78C18/78C17/78C14/78C14A/78C12A/78C11A/78C10A memory configuration
The µPD78C18/78C17/78C14/78C14A/78C12A/78C11A/78C10A can address a maximum of 64K bytes of memory.
The memory maps are shown in Figures 3-3 to 3-8. The external memory area and the on-chip RAM area can be
freely used as program memory and data memory. Since the access time for on-chip memory and external memory
are the same, processing can be executed at high speeds.
(1) Interrupt start addresses
The interrupt start addresses are all fixed as follows:
NMI .......................0004H
INTT0/INTT1 ......... 0008H
INT1/INT2 ............. 0010H
INTE0/INTE1 ......... 0018H
INTEIN/INTAD ...... 0020H
INTSR/INTST ........ 0028H
SOFTI .................... 0060H
(2) Call address table
The call address of a 1-byte call instruction (CALT) can be stored in the 64-byte area (for 32 call addresses)
from address 0080H to address 00BFH.
(3) Specific memory area
The reset start address, interrupt start addresses and the call table are allocated to addresses 0000H to 00BFH,
and this area takes account of these in use. Addresses 0800H to 0FFFH are directly addressable by a 2-byte
call instruction (CALF).
On-chip mask ROM allocation is shown below.
•
µPD78C18
: Addresses 0000H to 7FFFH
•
µPD78C17
: No mask ROM incorporated
•
µPD78C14/78C14A : Addresses 0000H to 3FFFH
•
µPD78C12A
: Addresses 0000H to 1FFFH
•
µPD78C11A
: Addresses 0000H to 0FFFH
•
µPD78C10A
: No mask ROM incorporated
With the µPD78C17/78C10A, a specific area can be set up externally.
44
CHAPTER 3
INTERNAL BLOCK FUNCTIONS
(4) On-chip data memory area
1K byte RAM is incorporated in addresses FC00H to FFFFH in the µPD78C18, and 256-byte RAM in addresses
FF00H to FFFFH in the µPD78C14A/78C12A/78C11A/78C10A. The RAM contents are retained in standby
operation
Caution
When internal RAM is used, the RAE bit of the MM register must be set to 1.
(5) External memory area
The possible area for external memory expansion is shown below. This area can be expanded in steps by
setting the memory mapping register.
•
µPD78C18
•
µPD78C14, 78C14A : 48K bytes (addresses 4000H to FEFFH)
•
µPD78C12A
: 56K bytes (addresses 2000H to FEFFH)
•
µPD78C11A
: 60K bytes (addresses 1000H to FEFFH)
: 31K bytes (addresses 8000H to FBFFH)
External memory can be expanded in steps in a 63K-byte area (addresses 0000H to FBFFH) for the µPD78C17,
and in a 64K-byte area (addresses 0000H to FEFFH) for the µPD78C10A. This setting is performed by the
MODE0 and MODE1.
The external memory is accessed using PD7 to PD0 (multiplexed address/data bus), PF7 to PF0 (address bus)
and the RD, WR and ALE signals. Both programs and data can be stored in the external memory.
(6) Working register area
A 256-byte working register area can be set in any memory locations (specified by the V register).
45
CHAPTER 3
INTERNAL BLOCK FUNCTIOS
Figure 3-3. Memory Map (µPD78C18)
0000H
On-chip ROM
32768 × 8-bit
0000H
RESET
0004H
NMI
0008H
INTT0/INTT1
0010H
INT1/INT2
0018H
INTE0/INTE1
0020H
INTEIN/INTAD
0028H
INTSR/INTST
0060H
SOFTI
0080H
LOW ADRS
0081H
HIGH ADRS
0082H
LOW ADRS
0083H
HIGH ADRS
00BEH
LOW ADRS
00BFH
00C0H
HIGH ADRS
7FFFH
8000H
External memory
31744 × 8-bit
On-chip RAM
1024 × 8-bit
Note
Standby area
FBFFH
FC00H
Call table
FFFFH
User's area
Note Can only be used when the RAE bit of the MM register is 1.
46
t=0
t=1
t = 31
CHAPTER 3
INTERNAL BLOCK FUNCTIONS
Figure 3-4. Memory Map (µPD78C17)
0000H
External memory
64512 × 8-bit
0000H
RESET
0004H
NMI
0008H
INTT0/INTT1
0010H
INT1/INT2
0018H
INTE0/INTE1
0020H
INTEIN/INTAD
0028H
INTSR/INTST
0060H
SOFTI
0080H
LOW ADRS
0081H
HIGH ADRS
0082H
LOW ADRS
0083H
HIGH ADRS
00BEH
LOW ADRS
00BFH
HIGH ADRS
On-chip RAM
1024 × 8-bit
Note
Standby area
FBFFH
FC00H
Call table
FFFFH
t=0
t=1
t = 31
Note Can only be used when the RAE bit of the MM register is 1.
47
CHAPTER 3
INTERNAL BLOCK FUNCTIOS
Figure 3-5. Memory Map (µPD78C14/78C14A)
0000H
On-chip ROM
16384 × 8-bit
0000H
RESET
0004H
NMI
0008H
INTT0/INTT1
0010H
INT1/INT2
0018H
INTE0/INTE1
0020H
INTEIN/INTAD
0028H
INTSR/INTST
0060H
SOFTI
0080H
LOW ADRS
0081H
HIGH ADRS
0082H
LOW ADRS
0083H
HIGH ADRS
00BEH
LOW ADRS
00BFH
00C0H
HIGH ADRS
3FFFH
4000H
External memory
48896 × 8-bit
On-chip RAM
256 × 8-bit
Note
Standby area
FEFFH
FF00H
Call table
FFFFH
User's area
Note Can only be used when the RAE bit of the MM register is 1.
48
t=0
t=1
t = 31
CHAPTER 3
INTERNAL BLOCK FUNCTIONS
Figure 3-6. Memory Map (µPD78C12A)
0000H
On-chip ROM
8192 × 8-bit
0000H
RESET
0004H
NMI
0008H
INTT0/INTT1
0010H
INT1/INT2
0018H
INTE0/INTE1
0020H
INTEIN/INTAD
0028H
INTSR/INTST
0060H
SOFTI
0080H
LOW ADRS
0081H
HIGH ADRS
0082H
LOW ADRS
0083H
HIGH ADRS
00BEH
LOW ADRS
00BFH
00C0H
HIGH ADRS
1FFFH
2000H
External memory
57088 × 8-bit
On-chip RAM
256 × 8-bit
Note
Standby area
FEFFH
FF00H
Call table
FFFFH
t=0
t=1
t = 31
User's area
1FFFH
Note Can only be used when the RAE bit of the MM register is 1.
49
CHAPTER 3
INTERNAL BLOCK FUNCTIOS
Figure 3-7. Memory Map (µPD78C11A)
0000H
On-chip ROM
4096 × 8-bit
0000H
RESET
0004H
NMI
0008H
INTT0/INTT1
0010H
INT1/INT2
0018H
INTE0/INTE1
0020H
INTEIN/INTAD
0028H
INTSR/INTST
0060H
SOFTI
0080H
LOW ADRS
0081H
HIGH ADRS
0082H
LOW ADRS
0083H
HIGH ADRS
00BEH
LOW ADRS
00BFH
00C0H
HIGH ADRS
0FFFH
1000H
External memory
61184 × 8-bit
On-chip RAM
256 × 8-bit
Note
Standby area
FEFFH
FF00H
Call table
FFFFH
User's area
Note Can only be used when the RAE bit of the MM register is 1.
50
t=0
t=1
t = 31
CHAPTER 3
INTERNAL BLOCK FUNCTIONS
Figure 3-8. Memory Map (µPD78C10A)
0000H
00BFH
00C0H
External memory
65280 × 8-bit
0000H
RESET
0004H
NMI
0008H
INTT0/INTT1
0010H
INT1/INT2
0018H
INTE0/INTE1
0020H
INTEIN/INTAD
0028H
INTSR/INTST
0060H
SOFTI
0080H
LOW ADRS
0081H
HIGH ADRS
0082H
LOW ADRS
0083H
HIGH ADRS
00BEH
LOW ADRS
00BFH
HIGH ADRS
On-chip RAM
256 × 8-bit
Note
Standby area
FEFFH
FF00H
Call table
FFFFH
t=0
t=1
t = 31
Note Can only be used when the RAE bit of the MM register is 1.
51
CHAPTER 3
INTERNAL BLOCK FUNCTIOS
3.5.2 µPD78CP18/78CP14 memory configuration
The µPD78CP18 can operate in any of 4 modes and the µPD78CP14 in any of 3 modes according to the MM register
mode specification.
•
µPD78C18 modeNote
•
µPD78C14 mode
•
µPD78C12A mode
•
µPD78C11A mode
Note Only the µPD78CP18 can operate in this mode.
In addition, the on-chip ROM address range can be specified to allow efficient mapping of external memory
(excluding PROM).
The vector area and call table area are the same in all modes.
Setting the hardware/software STOP mode or HALT mode allows on-chip RAM data to be retained with a low
consumption current.
The memory map for each mode is shown in Figures 3-9 to 3-12.
52
CHAPTER 3
INTERNAL BLOCK FUNCTIONS
Figure 3-9. Memory Map (µPD78C18 Mode)
0000H
On-chip EPROM
32768 × 8-bit
0000H
RESET
0004H
NMI
0008H
INTT0/INTT1
0010H
INT1/INT2
0018H
INTE0/INTE1
0020H
INTEIN/INTAD
0028H
INTSR/INTST
0060H
SOFTI
0080H
LOW ADRS
0081H
HIGH ADRS
0082H
LOW ADRS
0083H
HIGH ADRS
00BEH
LOW ADRS
00BFH
00C0H
HIGH ADRS
7FFFH
8000H
External memory
31744 × 8-bit
On-chip RAM
1024 × 8-bit
Note
Standby area
FBFFH
FC00H
Call table
FFFFH
t=0
t=1
t = 31
User's area
7FFFH
Note Can only be used when the RAE bit of the MM register is 1.
53
CHAPTER 3
INTERNAL BLOCK FUNCTIOS
Figure 3-10. Memory Map (µPD78C14 Mode)
0000H
On-chip EPROM
16384 × 8-bit
0000H
RESET
0004H
NMI
0008H
INTT0/INTT1
0010H
INT1/INT2
0018H
INTE0/INTE1
0020H
INTEIN/INTAD
0028H
INTSR/INTST
0060H
SOFTI
0080H
LOW ADRS
0081H
HIGH ADRS
0082H
LOW ADRS
0083H
HIGH ADRS
00BEH
LOW ADRS
00BFH
00C0H
HIGH ADRS
3FFFH
4000H
External memory
48896 × 8-bit
On-chip RAM
256 × 8-bit
Note
Standby area
FEFFH
FF00H
Call table
FFFFH
User's area
3FFFH
Note Can only be used when the RAE bit of the MM register is 1.
54
t=0
t=1
t = 31
CHAPTER 3
INTERNAL BLOCK FUNCTIONS
Figure 3-11. Memory Map (µPD78C12A Mode)
0000H
On-chip EPROM
8192 × 8-bit
0000H
RESET
0004H
NMI
0008H
INTT0/INTT1
0010H
INT1/INT2
0018H
INTE0/INTE1
0020H
INTEIN/INTAD
0028H
INTSR/INTST
0060H
SOFTI
0080H
LOW ADRS
0081H
HIGH ADRS
0082H
LOW ADRS
0083H
HIGH ADRS
00BEH
LOW ADRS
00BFH
00C0H
HIGH ADRS
1FFFH
2000H
External memory
57088 × 8-bit
On-chip RAM
256 × 8-bit
Note
Standby area
FEFFH
FF00H
Call table
FFFFH
t=0
t=1
t = 31
User's area
1FFFH
Note Can only be used when the RAE bit of the MM register is 1.
55
CHAPTER 3
INTERNAL BLOCK FUNCTIOS
Figure 3-12. Memory Map (µPD78C11A Mode)
0000H
On-chip EPROM
4096 × 8-bit
0000H
RESET
0004H
NMI
0008H
INTT0/INTT1
0010H
INT1/INT2
0018H
INTE0/INTE1
0020H
INTEIN/INTAD
0028H
INTSR/INTST
0060H
SOFTI
0080H
LOW ADRS
0081H
HIGH ADRS
0082H
LOW ADRS
0083H
HIGH ADRS
00BEH
LOW ADRS
00BFH
00C0H
HIGH ADRS
0FFFH
1000H
External memory
61184 × 8-bit
On-chip RAM
256 × 8-bit
Note
Standby area
FEFFH
FF00H
Call table
FFFFH
User's area
0FFFH
Note Can only be used when the RAE bit of the MM register is 1.
56
t=0
t=1
t = 31
CHAPTER 3
INTERNAL BLOCK FUNCTIONS
3.6 Timers
The timer system comprises two 8-bit interval timers. The two interval timers can also be cascaded to operate
as a 16-bit interval timer
The elapse of the interval time can be identified by the generation of a timer interrupt. In addition, a square wave
with the interval time as a half-cycle is obtained from the TO pin (see CHAPTER 5 TIMER FUNCTIONS for details).
3.7 Timer/Event Counter
This is a 16-bit timer/event counter which performs the following operations according to the operating mode set
by the program (see CHAPTER 6 TIMER/EVENT COUNTER FUNCTIONS for details).
• Interval timer function
• Event counter function
• Frequency measurement
• Pulse width measurement
• Programmable square-wave output
3.8 Serial Interface
This interface is used to perform serial data transfers in a multi-processor configuration or with various terminals,
and operates in asynchronous mode, synchronous mode, and I/O interface mode (see CHAPTER 7 SERIAL INTERFACE
FUNCTIONS for details).
3.9 Analog/Digital Converter
This consists of an 8-bit A/D converter with 8 analog inputs which uses the high-precision successive approximation
method, and 4 conversion result registers (CR0 to CR3) which hold the conversion results.
With two analog input selection methods, scan mode and select mode, and 4 registers (CR0 to CR3) to hold the
conversion results, software overhead is minimized (see CHAPTER 8 ANALOG/DIGITAL CONVERTER FUNCTIONS
for details).
3.10 Interrupt Control
There are 3 kinds of external interrupt request and 8 kinds of internal interrupt request, controlled according to
the status and priority of the interrupt mask register.
The 11 kinds of interrupt requests are divided into 6 groups, with 6 different priorities and 6 different interrupt
addresses (see CHAPTER 9 INTERRUPT CONTROL FUNCTIONS for details).
57
CHAPTER 3
INTERNAL BLOCK FUNCTIOS
3.11 Zero-Cross Detector
The INT1 pin and INT2/TI (PC3 dual-function) pin can be made to execute zero-cross detection operations by setting
the zero-cross mode register.
The zero-cross detector has a self-bias type high-gain amplifier. It biases the input to the switching point and
generates digital displacement in response to a small input displacement.
Figure 3-13. Zero-Cross Detector
µ PD78C18
External
capacitor
AC input signal
(1 to 1.8 VPP)
INT1
INT2/TI
To internal
circuitry
1 µF
Self bias
circuit enable
The zero-cross detector detects a negative-to-positive or positive-to-negative transition of the AC signal input
through an external capacitor and generates a digital pulse which changes from 0 to 1 or 1 to 0 at each transition
point.
Figure 3-14. Zero-Cross Detection Signal
AC input
signal
Zero-cross
detection
signal
A digital pulse generated in the zero-cross detector of the INT1 pin is set to the interrupt control circuit. The INTF1
interrupt request flag is set at the zero-cross point from negative to positive of the AC signal (rising edge), and if
INT1 interrupt is enabled, interrupt servicing is started. A digital pulse generated in the INT2/TI pin zero-cross detector
is sent to the interrupt control circuit and interrupt servicing can be started at the zero-cross point from positive to
negative of the AC signal as with the INT1 pin, and can also be used as a timer input clock.
58
CHAPTER 3
INTERNAL BLOCK FUNCTIONS
The zero-cross detection function can use the 50/60 Hz power signal as the basis for system timing. Further,
a special characteristic of the zero-cross function is that it can be used for servicing of interrupts at the zero-voltage
point. This makes it possible to control a device which uses voltage phase sensing such as a TRIAC or SCR, and
allows the µPD78C18 to be used for applications such as shaft speed and angle measurement.
When a capacitor is not connected to the INT1 and INT2 pins, they function as digital input pins.
The format of the zero-cross mode register (ZCM), which controls self-bias for zero-cross detection of the INT1
and INT2/TI pins, is shown in Figure 3-15.
Figure 3-15. Zero-Cross Mode Register Format
ZCM
7
6
5
4
3
2
1
0
–
–
–
–
–
ZC2
ZC1
–
INT1 pin
0
No self-bias generation
1
Self-bias generation
INT2/TI pin
0
No self-bias generation
1
Self-bias generation
When the ZC1 and ZC2 bits of the zero-cross mode register are set to to "0", a self-bias for zero-cross detection
of each pin is not generated and each pin responds as a normal digital input.
When the ZC1 and ZC2 bits are set to "1", a self-bias is generated and an AC input signal zero-cross can be detected
by connecting a capacitor to each pin. Each pin with ZC1 and ZC2 bits set to "1" can be directly driven without the
use of an external capacitor. In this case, each pin responds as a digital input. However, an input load current is
necessary and an external circuit output driver must be considered. Thus, when no zero-cross detection is executed
and each pin is used simply as an interrupt input or timer input, the ZC1 and ZC2 bits of the zero-cross mode register
should be set to "0".
RESET input sets both the ZC1 and ZC2 bit to "1" and a self-bias is generated.
When the PC3 (INT2/TI) pins is in port mode, no self-bias is generated regardless of the ZCM register setting.
Cautions 1. Unlike other CMOS circuits, a supply current is always present in the zero-cross detector
because of its operation points. This also applies in the standby modes (HALT and software/
hardware STOP modes). Thus, when the zero-cross detector is operated (with self-bias
generation: ZCx=1), slightly more current flows than without zero-cross detector operation,
and its effect is greater in the software STOP mode.
2. When the PC3 pin is used for zero-cross detection in the µPD78C18/78C14A/78C12A/78C11A,
no pull-up resistor should be incorporated.
In the hardware STOP mode, self-bias generation is stopped automatically.
59
[MEMO]
60
CHAPTER 4 PORT FUNCTIONS
4.1 Port A (PA7 to PA0)
This is an 8-bit input/output port which has input/output buffer and output latch functions (see Figure 4-1). Port
A can be set as to input or output bit-wise using the mode A register (MA). When set to input, the pins become
high-impedance.
In the µPD78C18/78C14A/78C12A/78C11A, pull-up resistors can be incorporated bit-wise.
Figure 4-1. Port A
WRM
MAn
latch
Internal bus
WRP
Output
latch
RD0
PAn
Output
buffer
RD1
When the corresponding bit of the mode A register is set (1), a port A pin functions as an input port pin, and when
reset (0), as an output port pin (see Figure 4-2).
When RESET is input or the hardware STOP mode is set, all bits of the mode A register are set and port A functions
as an input port (high-impedance).
Figure 4-2. Mode A Register Format
7
6
MA MA7 MA6
5
4
MA5 MA4
3
2
MA3
MA2
1
0
MA1 MA0
0
PAn = Output port
1
PAn = Input port
(n = 0 – 7)
PA
7
6
5
4
3
2
1
0
PA7
PA6
PA5
PA4
PA3
PA2
PA1
PA0
61
CHAPTER 4
PORT FUNCTIONS
(1) When specified as output port (MAn=0)
The output latch is effective, enabling data exchange by a transfer instruction between the output latch and
the accumulator. Direct bit setting/resetting of output latch contents is possible by an arithmetic or logical
operation instruction without the use of an accumulator. Once data is written to the output latch, the data
is held until a port A manipulation instruction is executed or the data is reset.
Figure 4-3. Port A Specified as Output Port
Internal bus
WRP
Output
latch
PAn
RD0
(2) When specified as input port (MAn=1)
PA line contents can be loaded into an accumulator by a transfer instruction. They can also be directly tested
bit-wise by an arithmetic or logical operation instruction without the use of an accumulator. In this case, too,
writing to the output latch is possible and data transferred from the accumulator by a transfer instruction is
stored in the entire output latch without regard to the input/output setting of the port. However, the output
latch contents for bits specified as input port bits cannot be loaded into the accumulator, and since the output
buffer is high-impedance, the contents are not output to an external pin (operating as an input pin). Thus data
stored in the output latch can be output to the external pin and loaded into the accumulator when the bit is
switched to output port mode.
Since input data is not latched, stable input is necessary when executing a data transfer instruction or a bit
test, etc.
Figure 4-4. Port A Specified as Input Port
Internal bus
WRP
62
Output
latch
RD1
PAn
CHAPTER 4
PORT FUNCTIONS
(3) Port A manipulation
Actual execution of an instruction which manipulates port A is performed as an 8-bit unit. If a port A read
instruction (MOV A, PA) is executed, the input line contents of the port specified for input and the output
latch contents of the port specified for output are loaded into an accumulator. When a port A write instruction
(MOV PA, A) is executed, data is written to the output latch of both ports specified for input and output, but
the output latch contents of a port specified as input are not output to an external pin.
Here, the data input/output manipulation is described when the high-order 4 bits (PA7 to PA4) of port A are
used as an active-low output port, and the low-order 4 bits (PA3 to PA0) are used as an input port. Since
the initial status of PA7 to PA0 after a reset is the input port status (high-impedance), the PA7 to PA4 output
port pins used as active-low have to be raised to the high level with a pull-up resistor to make them inactive.
Also, since the output latch contents are undefined after a reset, the active level (low) may be output at the
point of specification as an output port. Therefore, all ones should be written to the PA7 to PA4 output latches
before specification as an output port.
VDD
µ PD78C18
~
PA7
Active-low output
PA4
~
PA3
PA0
63
CHAPTER 4
PA Input/Output
PA Output Latch
7 6 5 4 3 2 1 0
RESET
; MA=0FFH
I I I I I I I I
PORT FUNCTIONS
Note
PA Pin
7 6 5 4 3 2 1 0
7 6 5 4 3 2 1 0
× × × × × × × ×
1 1 1 1 × × × ×
By pull-up resistor
1 1 1 1 0 0 0 0
…
MVI PA, 0F0H
1 1 1 1 × × × ×
By pull-up resistor
MVI A, 0FH
OOOO I I I I
Note
1 1 1 1 0 0 0 0
1 1 1 1 × × × ×
1 1 1 0 1 1 1 1
1 1 1 0 × × × ×
1 1 1 0 1 1 1 1
1 1 1 0 1 0 1 0
………
MOV MA, A;MA=0FH
…
MVI PA, 0EFH
MOV A, PA;A=11101010
Input data
Pin input data
Output latch contents
Note I:
O:
64
Input
Output
CHAPTER 4
PORT FUNCTIONS
4.2 Port B (PB7 to PB0)
Like port A, port B is an 8-bit input/output port with input/output buffer and output latch functions (see Figure 4-1). Port
B can be set as an input or output port bit wise using the mode B register (MB). When set to input, the pins become
high-impedance.
When the corresponding bit of the mode B register is set (1), a port B pin functions as an input port pin, and when
reset (0), as an output port pin (see Figure 4-5).
When RESET is input or the hardware STOP mode is set all bits of the mode B register are set and port B functions
as an input port (high-impedance).
In the µPD78C18/78C14A/78C12A/78C11A, pull-up resistors can be incorporated bit-wise.
Figure 4-5. Mode B Register Format
7
6
MB MB7 MB6
5
4
MB5 MB4
3
2
MB3
MB2
1
0
MB1 MB0
0
PBn = Output port
1
PBn = Input port
(n = 0 – 7)
PB
7
6
5
4
3
2
1
0
PB7
PB6
PB5
PB4
PB3
PB2
PB1
PB0
As with port A, direct bit setting/resetting of port B output latch contents is possible by an arithmetic or logical
operation instruction without the use of an accumulator. Data transfer to/from an accumulator is also possible.
65
CHAPTER 4
PORT FUNCTIONS
4.3 Port C (PC7 to PC0)
Port C (PC7 to PC0) is an 8-bit special input/output port which functions in either port mode or control signal input/
output mode according to the setting of the mode control C (MCC) register.
When the corresponding bit of mode control C register is set (1), the port C is set to control mode, and if reset
(0), set to port mode (see Figure 4-6).
When RESET is input or the hardware STOP mode is set, all bits of the mode control C register are reset and
all bits of port C are set to port mode.
In the µPD78C18/78C14A/78C12A/78C11A, pull-up resistors can be incorporated bit-wise.
Figure 4-6. Mode Control C Register Format
7
6
5
4
3
2
1
0
MCC MCC7 MCC6 MCC5 MCC4 MCC3 MCC2 MCC1 MCC0
66
0
PC0 = Port mode
1
PC0 = TXD output
0
PC1 = Port mode
1
PC1 = RXD input
0
PC2 = Port mode
1
PC2 = SCK input/output
0
PC3 = Port mode
1
PC3 = INT2/TI input
0
PC4 = Port mode
1
PC4 = TO output
0
PC5 = Port mode
1
PC5 = CI input
0
PC6 = Port mode
1
PC6 = CO0 output
0
PC7 = Port mode
1
PC7 = CO1 output
CHAPTER 4
PORT FUNCTIONS
(1) Port mode
Like port A, port C is an 8-bit input/output port with input/output buffer and output latch functions (see Figure
4-1). When port C is set to port mode by the mode control C register, it can be set bit-wise as an input or
output port by means of the mode C register (MC). When set to input port, the pins become high-impedance.
When the corresponding bit of the mode C register is set (1), a port C pin functions as an input port pin, and
when reset (0), as an output port pin (see Figure 4-7).
When RESET is input or the hardware STOP mode is set all bits of the mode C register are set and port C
functions as an input port (high-impedance).
Figure 4-7. Mode C Register Format
7
6
MC MC7 MC6
5
4
MC5 MC4
3
2
MC3
MC2
1
0
MC1 MC0
0
PCn = Output port
1
PCn = Input port
(n = 0 – 7)
PC
7
6
5
4
3
2
1
0
PC7
PC6
PC5
PC4
PC3
PC2
PC1
PC0
As with port A, direct bit setting/resetting of port C output latch contents is possible by an arithmetic or logical
operation instruction without the use of an accumulator. Data transfer to /from an accumulator is also possible.
(2) Control signal input/output mode
Port C input/output pins (PC7 to PC0) can be used bit-wise as control signal inputs or outputs by setting (1)
the relevant bit of the mode control C register, regardless of the mode C register setting. When the PCn
pin is used for a control signal (MCCn=1), the control signal status is ascertained by execution of a port C
read instruction or test instruction.
(a) When PCn is control signal output
When MCn=1, the status of the PCn pin control signal can be read into an accumulator or tested by
executing a port C read instruction or test instruction.
When MCn=0, the internal control signal status can be read into an accumulator or tested by executing
a port C read instruction or test instruction (see Figure 4-8).
67
CHAPTER 4
PORT FUNCTIONS
Figure 4-8. Port C Specified as Control Signal Output
Control
signal
PCn (Control signal output)
MCn = 0
RDP
MCn = 1
Internal
bus
(b) When PCn is control signal input
When MCn=1, the status of the PCn pin control signal can be read into an accumulator by a port C read
instruction or tested by a port C test instruction.
Figure 4-9. Port C Specified as Control Signal Input
Control
signal
PCn (Control signal output)
RDP
MCn = 1
Internal
bus
Cautions 1. When MCC3 is rewritten, INTF2 may be set. After rewriting, INTF2 should be reset by the SKIT
instruction.
2. When TO (PC4), CO0 (PC6) and CO1 (PC7) are used as active-low signal outputs, the following
manipulation is required.
Since port C is entirely set as an input port (high-impedance) in its initial status after a reset,
TO, CO0 and CO1 used as active-low pin have to be raised to the high level with a pull-up
resistor to make them inactive. Also, before switching to the control signal output mode by
means of the mode control C register, "1" must be written to the port C output latch to make
the port C output level and output latch contents equal. Port C is then switched to the control
signal output mode by means of the mode control C register.
68
CHAPTER 4
PORT FUNCTIONS
VDD
µ PD78C18
TO (PC4)
Active-low output
CO0 (PC6)
CO1 (PC7)
MVI
PC, 0FFH ; PORT C OUTPUT LATCH=1
MVI
A, 0FFH
MOV MCC, A
;
; PORT C CONTROL MODE
69
CHAPTER 4
PORT FUNCTIONS
4.4 Port D (PD7 to PD0)
µPD78C18/78C14/78C14A/78C12A/78C11A/78CP18/78CP14
Port D is an 8-bit special input/output port; in addition to functioning as a general-purpose input/output port (port
mode), this port also functions as a multiplexed address/data bus.
Port/expansion mode can be specified for port D as a byte unit by means of the memory mapping register (see
Table 4-1).
Table 4-1. Operation of PD7 to PD0 (µPD78C18/78C14/78C14A/78C12A/78C11A/78CP18/78CP14)
PD7 to PD0
MM2, MM1=0, 0
MM2, MM1≠0, 0
Port mode
Expansion mode
Port D is set to port mode when the MM2 and MM1 bits of the memory mapping register are reset (0), and to
expansion mode in all other cases (see 11.1.1 Memory mapping register (MM)).
(1) Port mode
Port D is an 8-bit input/output port which has input/output buffer and output latch functions in the same way
as port A, except that input or output port setting is performed as a byte (8-bit) unit.
Port D can be set as input or output as a byte unit by the MM0 bit of the memory mapping register: It functions
as an input port when the MM0 bit is reset (0), and as an output port when the MM0 bit is set (1).
Except for having input/output specified as a byte unit, port D operation is the same as for port A; Direct
bit setting/resetting of output latch contents is possible by an arithmetic or logical operation instruction
without the use of an accumulator, and data transfer to/from an accumulator is also possible.
(2) Expansion mode
External memory expansion up to 256 bytes is possible using the port D input/output pins (PD7 to PD0) as
a multiplexed address/data bus. Also, when a large external memory expansion is made, this is done by using
PF7 to PF0 as the address bus (see CHAPTER 11 EXTERNAL DEVICE ACCESSES AND TIMINGS for details).
µPD78C17/78C10A
The port operates only as a multiplexed address/data bus (AD7 to AD0), and has no port function
Cautions 1. When the port D input/output pins (PD7 to PD0) are functioning as an address/data bus (AD7
to AD0), the internal address bus status is output in synchronization with ALE in all machine
cycles.
2. Emulation cannot be performed by an emulator for a program which varies the port D
operating mode dynamically. Therefore, once the mode has been set, it should not be changed
to a different mode.
70
CHAPTER 4
PORT FUNCTIONS
4.5 Port F (PF7 to PF0)
µPD78C18/78C14/78C14A/78C12A/78C11A/78CP18/78CP14
Port F is an 8-bit special input/output port; in addition to functioning as a general-purpose input/output port (port
mode), this port also functions as an address bus.
Port/expansion mode can be specified in steps for PF7 to PF0 by means of the memory mapping register (see
11.1.1 Memory mapping register (MM)).
(1) Port mode
Like port A, port F is an 8-bit input/output port with input/output buffer and output latch functions (see Figure
4-1. Port A).
Port F can be set bit-wise as an input or output port by means of the mode F register (MF). When set to
input, the pins become high-impedance.
When the corresponding bit of the mode F register is set (1), a port F pin functions as an input port pin, and
when reset (0), as an output port pin.
When RESET is input or the hardware STOP mode is set all bits of the mode F register are set.
Figure 4-10. Mode F Register Format
7
MF MF7
6
5
4
3
2
1
0
MF6
MF5
MF4
MF3
MF2
MF1
MF0
0
PFn = Output port
1
PFn = Input port
(n = 0 – 7)
PF
7
6
5
4
3
2
1
0
PF7
PF6
PF5
PF4
PF3
PF2
PF1
PF0
As with port A, direct bit setting/resetting and bit testing of port F output latch contents is possible by an
arithmetic or logical operation instruction without the use of an accumulator. Data transfer to/from an
accumulator is also possible.
71
CHAPTER 4
PORT FUNCTIONS
(2) Expansion mode
Port F input/output pins (PF7 to PF0) can be used as address outputs corresponding to the size of external
expansion memory, as shown in Table 4-2. This setting is performed by means of the memory mapping
register.
Pins not used as address outputs are set to port mode.
Table 4-2. Operation of PF7 to PF0 (µPD78C18/78C14/78C14A/78C12A/78C11A/78CP18/78CP14)
PF7
PF6
PF5
PF4
PF3
PF2
Port
Port
Port
Port
Port
Port
Port
Port
Port
Port
AB11
AB10
Port
Port
AB13
AB12
AB11
AB10
AB15
AB14
AB13
AB12
AB11
AB10
PF1
PF0
External Address Space
Port
Port
Up to 256 bytes
AB9
AB8
Up to 4K bytes
AB9
AB8
Up to 16K bytes
AB9
AB8
Up to 31K/48K/56K/60K bytesNote
Note 31K (µPD78C18), 48K (µPD78C14/78C14A), 56K (µPD78C12A), 60K (µPD78C11A). The operation of the
µPD78CP18 and 78CP14 differ depending on the setting of bits MM5 to MM7 of the memory mapping
register.
µPD78C17/78C10A
These pins function as address outputs corresponding to the size of externally installed memory according to the
MODE0 and MODE1 pin settings.
Pins which are not used as address outputs can be used as general-purpose input/output port pins which have
the same port functions as port A, with input/output setting performed by the mode F register.
Table 4-3. Operation of PF7 to PF0 (µPD78C17/78C10A)
MODE1
MODE0
PF7
PF6
PF5
PF4
0
0
Port
Port
Port
Port
0
1
Port
Port
1
0
1
1
PF3
PF2
PF1
PF0
External Address Space
AB11 AB10
AB9
AB8
4K bytes
AB13 AB12 AB11 AB10
AB9
AB8
16K bytes
AB8
63K/64K bytesNote
Setting prohibited
AB15 AB14 AB13 AB12 AB11 AB10
AB9
Note 63K (µPD78C17), 64K (µPD78C10A)
Cautions 1. Pins not used as address bus pins output the internal address bus status in all machine cycles.
When the address changes, undefined data is output.
2. Emulation cannot be performed by an emulator for a program which varies the port F
operating mode dynamically. Therefore, once the mode has been set, it should not be changed
to a different mode.
When the 63K/64K-byte mode is used with the µPD78C17/78C10A, instructions which output data to port D or
port F should not be executed; if such an instruction is executed, the WR signal will be output.
72
CHAPTER 4
PORT FUNCTIONS
4.6 Operation of Arithmetic and Logical Operation Instruction Involving a Port and Immediate Data
With the following instructions which perform arithmetic and logical operations involving a port and immediate
data, the operation differs depending on the input/output setting of the port.
Table 4-4. Operation of Arithmetic/Logical Operation Instructions Involving a Port
Mnemonic
ACI, ADI, ADINC
Operand
sr2, byte
Instruction
Arithmetic operation
SBI, SUI, SUINB
ANI, ORI, XRI
Logical operation
GTI, LTI
Comparison
EQI, NEI
Match detection
OFFI, ONI
Test
Instruction operations are as follows:
(1) The port status is input.
Output mode pin:
Output latch status is input.
Input mode pin:
Pin external status is input.
(2) The arithmetic/logical operation is performed on the input data and immediate data.
(3) The entire 8-bit operation result data is transferred to the port output latch.
For input mode pins, the result of the operation with the pin external status is transferred to the output latch.
Caution (3) applies only to the arithmetic operations and logical operations in Table 4-4.
Port output latch initialization should be performed by a transfer instruction (MOV, MVI).
73
[MEMO]
74
CHAPTER 5 TIMER FUNCTIONS
5.1 Timer Configuration
The timer system in the µPD78C18 consists of two 8-bit interval timers (TIMER0 and TIMER1) and a timer F/F.
Timer operation and square-wave output is controlled by the timer mode register (TMM).
Each interval timer (TIMER0 and TIMER1) consists of an 8-bit upcounter, an 8-bit comparator, and 8-bit timer REG0/
1 (TM0 and TM1).
(1) Upcounter
This counts up using the input clock specified by the timer mode register (TMM).
(2) Timer REG0, 1 (TM0, TM1)
These are 8-bit registers used to set the interval time.
(3) Comparator
The comparator compares the upcounter contents with the timer REG0/1 contents, and if they match, clears
the upcounter and generates an internal interrupt (INTT0/INTT1).
(4) Timer F/F
This F/F is inverted by a TIMER0/TIMER1 match signal or the internal clock (φ3). The output of this timer F/
F can be output to the TO pin (dual function as PC4). The timer F/F output can be used irrespective of the
PC4 pin mode status as the basic timer of the timer/event counter according to the specification of the timer/
event counter mode register or as the serial clock (SCK) according to the serial mode register specification.
The timer is also used for generation of the oscillator stabilization time when standby mode (STOP) is released
(see 10.1 Standby Functions for details).
75
CHAPTER 5
TIMER FUNCTIONS
Figure 5-1. Timer Block Diagram
φ3
TIMER0
Timer
F/F
TIMER1
To timer/event counter
PC3/TI
To serial interface
clear
φ 12
φ 384
Timer mode
register
φ 12
Upcounter
clear
Upcounter
φ 384
Comparator
Comparator
Timer REG0
(TM0)
Timer REG1
(TM1)
INTT0
Internal bus
Remark
φ3 = fXX × 1/3
φ12 = fXX × 1/12
φ384 = fXX × 1/384
fXX : Oscillator frequency (MHz)
76
INTT1
PC4/TO
CHAPTER 5
TIMER FUNCTIONS
5.2 Timer Mode Register (TMM)
This is an 8-bit register which specifies the operating mode of the two interval timers (TIMER0 and TIMER1) and
the timer F/F. Its configuration is shown in Figure 5-2.
(1) TF0 & TF1 (bits 0 & 1)
These bits perform timer F/F reset specification and input clock specification. The internal clock (φ3) is obtained
by dividing the oscillator frequency by 3.
(2) CK00 & CK01 (bits 2 & 3)
These bits specify the TIMER0 input clock. Internal clocks φ12 and φ384 are obtained by dividing the oscillator
frequency by 12 and 384 respectively.
(3) TS0 (bit 4)
TS0 controls the operation of the TIMER0 upcounter. When TS0 is "1", the upcounter is cleared to 00H and
the count-up is stopped; when changed from "1" to "0", the upcounter starts counting up from 00H. However,
if, after this bit is set to "0" and the count has begun, "0" is written to the bit again, the upcounter is not cleared
and the count continues.
(4) CK10 & CK11 (bits 5 & 6)
These bits specify the TIMER1 input clock.
(5) TS1 (bit 7)
TS1 controls the operation of the TIMER1 upcounter and operates in the same way as the TS0 bit.
RESET input sets the timer mode register to FFH, clears and stops the upcounter of both TIMER0 and TIMER1,
and resets the timer F/F.
77
CHAPTER 5
TIMER FUNCTIONS
Figure 5-2. Timer Mode Register (TMM) Format
7
TMM
TS1
6
5
CK11 CK10
4
TS0
3
2
CK01 CK00
1
0
TF1
TF0
Timer F/F input & operating mode specification
0
0
TIMER0 comparator match signal
0
1
TIMER1 comparator match signal
1
0
Internal clock (φ 3 )
1
1
Timer F/F reset
TIMER0 input clock specification
0
0
Internal clock (φ 12)
0
1
Internal clock (φ 384 )
1
0
External pulse (TI pin falling edge) input
1
1
Disable
TIMER0 operation specification
0
Count-up
1
Reset
TIMER1 input clock specification
0
0
Internal clock (φ 12)
0
1
Internal clock (φ 384)
1
0
External pulse (TI pin falling edge) input
1
1
TIMER0 comparator match signal
TIMER1 operation specification
78
0
Count-up
1
Reset
CHAPTER 5
TIMER FUNCTIONS
5.3 Timer Operations
Interval timer operation is performed for the two timers using the following input clocks according to the
specification of the timer mode register (TMM).
(1) Internal clock (φ12)
When the internal clock (φ12) is specified as the upcounter input clock, the timer operates as an interval timer
with an interval from 1 µs to 256 µs (at 12 MHz operation) with a 1 resolution of 1 µs.
(2) Internal clock (φ384)
When the internal clock (φ384) is specified as the upcounter input clock, an interval time from 32 µs to 8.192
ms can be selected (at 12 MHz operation) with a resolution of 32 µs.
(3) External pulse (TI)
When an external pulse (TI input) is specified as the upcounter input clock, the timer operates as an interval
timer of any desired resolution. Also, when the upcounter counts external pulses up to the value set in timer
REG0/1 (TM0/TM1), it can also be used as an event counter which generates internal timer interrupts (INTT0/
INTT1). However, it is not possible to read the count data (the upcounter contents) during the count.
To prevent errors due to noise signals in the TI pin, sampling is performed by a sampling pulse with a 1-state
(250 ns: 12 MHz) cycle. Thus an input signal of less than 1 state is eliminated, and a high level or low level
duration of 2 states or more is necessary for a signal to be acknowledged as a TI pin input signal.
The upcounter count operation is performed by falling edge input on the TI pin.
(4) TIMER0 output (can only be specified for TIMER1)
This can only be specified for TIMER1. The timer operates as a 16-bit interval timer which counts TIMER0
match signals as the TIMER1 upcounter input. An interval from 1 µs to 65.536 ms or from 32 µs to 2.1 s
can be selected (at 12 MHz operation).
Since both TIMER0 and TIMER1 perform the same operation, TIMER0 operation is described here.
Interval timer operation is started by setting the count value in timer REG0 and writing the necessary data to the
timer mode register. The upcounter counts up every input clock cycle, while the comparator constantly compares
the contents of the counting upcounter and the contents of timer REG0, and generates an internal interrupt (INTT0)
if they match. When a match occurs, the upcounter is cleared and the count-up starts again from 00H. Thus TIMER0
functions as an interval timer which generates repeated interrupt requests using the value set in timer REG0 as the
interval. When timer REG0 is set, an interrupt is generated on the 256th count.
Cautions 1. When data is written to timer REG0, output of the comparator match signal is disabled, and
therefore INTT0 is not generated.
2. After RESET input, the contents of TM0 are undefined.
Ensure that TM0 initialization is performed by the program before the timer is started.
When the TIMER0 match signal is selected as the timer F/F input and the upcounter contents and the timer REG0
contents match, the timer F/F contents are inverted and a square wave can be output from the TO pin. The pulse
width of the square wave output to the TO pin is determined by the count value set in timer REG0. If 0 is set, the
timer F/F contents are inverted and INTT0 is generated by the comparator match signal generated every 256 counts.
The INTT0 timer interrupt is disabled by setting MKT0 (bit 1 of the interrupt mask register MKL).
79
[MEMO]
80
CHAPTER 6 TIMER/EVENT COUNTER FUNCTIONS
The µPD78C18 is equipped with a multi-function 16-bit timer/event counter which performs the following
operations:
• Interval timer function (see 6.3.1 Interval timer mode)
• External event counter function (see 6.3.2 Event counter mode)
• Frequency measurement (see 6.3.3 Frequency measurement mode)
• Pulse width measurement (see 6.3.4 Pulse width measurement mode)
• Programmable square-wave output (see 6.3.5 Programmable rectangular-wave output mode)
6.1 Timer/Event Counter Configuration
The configuration of the timer/event counter is shown in Figure 6-1.
Figure 6-1. Timer/Event Counter Block Diagram
Internal bus
Timer event counter
capture REG (ECPT)
φ 12
OV
Input
control
Clear
control
Output
control
PC5/CI
Timer/event counter
upcounter (ECNT)
TO
PC6/CO0
PC7/CO1
Comparator
Timer/event counter
REG1 (ETM1)
Timer/event counter
REG0 (ETM0)
CP0
CP1
Mode registers
(ETMM, EOM)
EIN
Interrupt
control
Comparator
INTE0
INTE1
INTE IN
Internal bus
Edge
detection
Remark
φ12=fXX ×
1
12
fXX: Oscillator frequency
81
CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
(1) Timer/event counter upcounter (ECNT)
ECNT is a 16-bit upcounter which counts input pulses, and is cleared by the clear control circuit.
The OV flag is set if overflow occurs. The OV flag can be tested by the SKIT instruction (see 9.1 (6) Test
flag register).
(2) Timer/event counter capture register (ECPT)
The ECPT register is a 16-bit buffer register which holds the ECNT contents. The timing for latching of the
ECNT contents by the ECPT register is as follows according to the input to the ECNT.
The ECPT register latches the ECNT contents on the fall of the CI input when the input to ECNT is (5) (i) Internal
clock (φ12), or (ii) Internal clock while CI input is high, and on the fall of TO when the input to ECNT is (iii) CI
input or (iv) CI input while TO output is high.
Table 6-1. Timing for Latching in ECPT
ETMM
ECNT Input
ET1
ET0
0
0
Internal clock (φ12)
0
1
φ12 while CI is high
1
0
CI inputNote 1
1
1
CI input while TO is highNote 1
Notes 1.
2.
ECNT Latch Timing
CI input falling edge
TO falling edgeNote 2
Falling edge input
The TO signal cannot be used when timer F/F input is used as internal clock φ3 (see Figure
5-1. Timer Block Diagram).
(3) Timer/event counter REG0/1 (ETM0/ETM1)
These are two 16-bit registers used to set the count value.
Cautions 1. When 0 is set, a match signal (CP0/CP1) is generated from the comparator every count
of 65536 (10000H).
2. When data is written to ETM0/ETM1, output of the comparator match outputs (CP0/CP1)
are disabled, and therefore INTE0/INTE1 are not generated.
(4) Comparator
The comparator compares the contents of ECNT and ETM0/ETM1, and if a match is detected, outputs a
coincidence signal (CP0/CP1)
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CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
(5) Input control circuit
This circuit controls input to ECNT. The input to ECNT is determined as follows according to the specification
of the timer/event counter mode register (ETMM).
(i)
Internal clock (φ12)
(ii)
Internal clock while CI input is high
(iii) CI input
(iv) CI input while TO output is high
To prevent errors due to noise signals in the CI pin, sampling is performed by a sampling pulse with φ3 cycle
(250 ns at 12 MHz operation). Thus an input signal of less than 1 state (250 ns at 12 MHz operation) is
eliminated, and a high level or low level duration of 2 states (500 ns at 12 MHz operation) or more is necessary
for a signal to be acknowledged as a CI pin input signal.
Caution
In CI pin edge detection, noise elimination is performed by the internal sampling clock (φ3)
Table 6-2. ECNT Inputs
ETMM
ECNT Input
ET1
ET0
0
0
Internal clock (φ12)
0
1
φ12 while CI input is high
1
0
CI inputNote
1
1
CI input while TO is highNote
Note Falling edge input
(6) Clear control circuit
This circuit clears ECNT as follows according to the specification of the timer/event counter mode register
(ETMM).
(i)
Remains cleared
(ii)
Not cleared
(iii) Match of ECNT and ETM1
(iv) CI input falling edge or TO falling edge
In case (iv), the operation is as shown in Table 6-3 according to the ECNT input.
83
CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
Table 6-3. ECNT Clearing
ETMM
ECNT Input
EM1
EM0
ET1
ET0
0
0
×
×
0
1
×
×
1
0
0
0
Internal clock (φ12)
0
1
φ12 while CI input is high
1
0
CI input
1
1
CI input while TO is high
×
×
No relation
1
1
No relation
ECNT Clearing
Stop after clearing
Free running (not cleared)
CI input falling edge
TO falling edgeNote
Match of ECNT and ETM1
Note The TO signal cannot be used when timer F/F input is used as internal clock φ3 (see Figure 5-1. Timer
Block Diagram).
When (iv) is specified in the clear mode, the clear operation is performed after the capture operation.
(7) Interrupt control circuit
This circuit controls timer/event counter interrupts. Interrupt sources are shown below; an interrupt request
flag is set (1) by each source.
(i)
ECNT/ETM0 match signal
→ INTE0
(ii)
ECNT/ETM1 match signal
→ INTE1
(iii)
CI input falling edge or TO falling edge → INTEIN
In case (iii), the setting is as shown in Table 6-4 according to the ECNT input as in case (ii) of item (6) Clear
control circuit.
Table 6-4. INTEIN Interrupt Request Flag Setting
ETMM
ECNT Input
ET1
ET0
0
0
Internal clock (φ12)
0
1
φ12 while CI input is high
1
0
CI inputNote 1
1
1
CI input while TO is highNote 1
Notes
Interrupt Request Flag Setting
CI input falling edge
TO falling edgeNote 2
1. Falling edge input
2. The TO signal cannot be used when timer F/F input is used as
internal clock φ3 (see Figure 5-1. Timer Block Diagram).
84
CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
(8) Output control circuit
This circuit controls the two channel pulse outputs (CO0 & CO1), and operates as a timer/event counter
enabling the pulse width and cycle to be varied.
Pulse output is varied by the following signals.
(i)
Match of ECNT and ETM0
(ii)
Match of ECNT and ETM1
(iii)
CI input fallng edge
(9) Mode registers
These are two 8-bit registers which specify the operation of the timer/event counter and output control circuit
(see 6.2 Mode Registers for details).
6.2 Mode Registers
The timer/event counter has two mode registers: The timer/event counter mode register (ETMM) which specifies
the operating mode, and the timer/event counter output mode register (EOM) which specifies the operation of the
output control circuit.
6.2.1 Timer/event counter mode register (ETMM)
This is an 8-bit register which controls the timer/event counter; its configuration is shown in Figure 6-2.
(1) ET0 & ET1 (bits 0 & 1)
These bits specify the timer/event counter upcounter (ECNT) input clock, latch timing, and INTEIN interrupt
flag setting conditions. They may also be used for clear mode specification (when EM1=1 and EM0=0).
The internal clock (φ12) is obtained by dividing the oscillator frequency by 12.
(2) EM0, & EM1 (bits 2 & 3)
These bits control the ECNT clear mode. When the value of the EM0 bit and EM1 bit is "00", ECNT is cleared
to 0000H and counting up is not performed.
When the EM0 and EM1 bits are set to any value other than "00", ECNT counts up using the input clock; ECNT
is cleared by the conditions shown in Figure 6-2, after which the count starts again from 0000H.
When EM0=0 and EM1=1, the conditions for clearing ECNT are as follows, according to the input clock
specification.
•
When ET1=0 and ET0=0, or ET1=0 and ET0=1, ECNT is cleared by the falling edge of the CI input (see
6.3.4 Pulse width measurement mode).
•
When ET1=1 and ET0=0, or ET1=1 and ET0=1, ECNT is cleared by the falling edge of the TO input (see
6.3.3 Frequency measurement mode).
(3) CO00 & CO01 (bits 4 & 5)
These bits specify the timing for transfer to the output latch of the level of the LV0 level F/F shown in Figure
6-3. When CO00=0 and CO01=1, the LV0 level is transferred to the output latch in the event of either a match
between ECNT and ETM0 or a fall of the CI input. When CO00=1 and CO01=1, the level is transferred in
the event of a match between ECNT and ETM0 or a match between ECNT and ETM1.
When the LD0 bit of the timer/event counter output mode register (EOM) is set (1), the LV0 level is inverted
after transfer to the output latch.
85
CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
(4) CO10 & CO11 (bits 6 & 7)
In a similar way to the CO00 and CO01 bits, these bits specify the timing for transfer to the output latch of
the level of the LV1 level F/F. When CO10=0 and CO11=1, or CO10=1 and CO11=1, the LV1 level is
transferred to the output latch as with the CO00 and CO01 bits.
When the LD1 bit of the timer/event counter output mode register (EOM) is set (1), the LV1 level is inverted
after transfer to the output latch.
The timer/event counter mode register is reset to 00H by RESET input and in the hardware STOP mode.
86
CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
Figure 6-2. Timer/Event Counter Mode Register Format
7
6
5
4
3
ETMM CO11 CO10 CO01 CO00 EM1
2
1
0
EM0
ET1
ET0
ECNT input clock
0
0
Internal clock ( φ 12)
0
1
φ 12 while CI input is high
1
0
CI input
1
1
CI input while TO is high
ECNT clear mode
0
0
0
1
1
0
1
1
Stop after clearing
Free running
Cleared every full count
Cleared on fall of CI input
(ET1=0)
Cleared on fall of TO
(ET1=1)
Cleared by match between ECNT and ETM1
CO0 output timing
0
0
Match between ECNT and ETM0
0
1
Setting prohibited
1
0
1
1
Match between ECNT and ETM0, or fall of
CI input
Match between ECNT and ETM0, or match
between ECNT and ETM1
CO1 output timing
0
0
Match between ECNT and ETM1
0
1
Setting prohibited
1
0
1
1
Match between ECNT and ETM1, or fall of
CI input
Match between ECNT and ETM0, or match
between ECNT and ETM1
87
CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
6.2.2 Timer/event counter output mode register (EOM)
This is an 8-bit register which controls the operation of the timer/event counter output control circuit.
First, the configuration of the functions of the output control cycle will be described. The block diagram of the
CO0 output of the output control circuit is shown in Figure 6-3.
The CO0 output is a master/slave type output, and the first-stage level F/F (LV0) holds the level to be output next.
The next-stage output latch is used to output the LV0 level off chip.
For the timing for inversion of the LV0 level and output off chip from LV0, the output timing specified by the timer/
event counter mode register is used.
The configuration of the CO1 output is the same as that of the CO0 output.
Figure 6-3. Output Control Circuit Block Diagram (CO0 Output)
Level F/F
LRE0
R
LRE1
S
LD0
Q
LV0
INV
Output latch
D
O
PC6/CO0
CK
CP0
CP1
CI
LO0
The timer/event counter output mode register performs initialization and operation control for the output control
circuit above; its configuration is shown in Figure 6-4.
(1) LO0 & LO1 (bits 0 & 4)
When LO0 or LO1 bit is set (1), the level of the level F/F (LV0 or LV1) is output to the output pin. These bits
are automatically reset (0) when the level is output.
(2) LD0 & LD1 (bits 1 & 5)
These bits determine whether or not the LV0/LV1 level is inverted using the timing specified by the timer/
event counter mode register. When the LD0/LD1 bit is set (1), the LV0/LV1 level is inverted using the specified
output timing. When the LD0/LD1 bit is reset (0), inversion is disabled.
(3) LRE0, LRE1, LRE2, LRE3 (bits 2, 3, 6, 7)
These bits perform level F/F setting/resetting: When the LRE0 or LRE2 bit is set (1), LV0 or LV1 is reset
respectively; and when LRE1/LRE3 is set (1), LV0/LV1 is set.
These bits automatically return to "0" when the level F/F is set/reset.
88
CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
The timer/event counter output mode register is reset to 00H by RESET input and in the hardware STOP mode.
Figure 6-4. Timer/Event Counter Output Mode Register Format
7
EOM
6
LRE3 LRE2
5
4
LD1
LO1
3
2
LRE1 LRE0
1
0
LD0
LO0
LV0 data output
0
No operation
1
LV0 contents output (output trigger)
LV0 level inversion
0
Disable
1
Enable
LV0 set/reset
0
0
No operation
0
1
LV0 reset
1
0
LV0 set
1
1
Setting prohibited
LV1 data output
0
No operation
1
LV1 contents output
LV1 level inversion
0
Disable
1
Enable
LV1 set/reset
0
0
No operation
0
1
LV1 reset
1
0
LV1 set
1
1
Setting prohibited
89
CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
6.3 Timer/Event Counter Operation
Timer/event counter operation is started by setting the count value and operating mode following the procedure
shown in Figure 6-5. Once these settings have been made, operation continues in that mode until the mode register
is set again.
Figure 6-5. Timer/Event Counter Setting Procedure
RESET input
Clear timer/event counter
upcounter (ECNT)
Set count value in timer/event
counter REG0/1
(ETM0/1)
Timer/event counter output
mode register (EOM) setting
; In case of programmable
rectangular-wave output
Timer/event counter
mode register (ETMM) setting
Port C mode
setting (MCC)
Start of count
Interrupt
Pin output
6.3.1 Interval timer mode
In this mode, the timer functions as an interval timer which generates interrupts repeatedly with the specified
count time as the interval. This interval timer allows a count to be specified from 1 µs to 65.535 ms with a resolution
of 1 µs (at 12 MHz operation).
After the timer/event counter upcounter (ECNT) is cleared, the count value is set in timer/event counter REG0/
1 (ETM0/ETM1). Then when the data shown in Figure 6-6 is set in the timer/event counter mode register (ETMM),
the timer/event counter operates as an interval timer using the internal clock (φ12) as the input clock.
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CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
Figure 6-6. Timer/Event Counter Mode Register Setting (Interval Timer Mode)
ETMM
7
6
5
4
3
2
1
0
0
0
0
0
1
1
0
0
Internal clock ( φ 12) count
ECNT cleared by match of ECNT
and ETM1 contents
ECNT counts up every 1 µs, and the respective comparator compares the ECNT count with the ETM0/ETM1
contents, and if a match is detected generates an internal interrupt (INTE0/INTE1) by means of a match signal (CP0/
CP1). Only in the event of a match between ECNT and ETM1, the ECNT contents are cleared and the count starts
again from 0000H. Thus the timer functions as an interval timer which repeatedly generates interrupts using the
count time determined by the count value set in ETM1 as the interval (see Figure 6-7).
Caution Since ETMM setting and the start of the internal clock are asynchronous, it should be noted that
some degree of error may arise in the first interval.
Internal interrupts can be disabled by setting (1) the MKE0/MKE1 bits of the interrupt mask register (MKL).
Figure 6-7. Interval Timer Mode Operation
Internal
clock
(φ 12)
m
0
n0
m
n0
CP0
CP1
INTE0
INTE1
Interrupt
acknowledgment
Start
(ETMM setting)
Remark
ETM0=m
Interrupt
ECNT
acknowledgment
clearance
Interrupt
ECNT
acknowledgment
clearance
(m<n: m, n; count value)
ETM1=n
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CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
6.3.2 Event counter mode
In this mode, external pulses input to the CI pin (dual function as PC5) are counted.
After first clearing ECNT, the external even count is performed by setting the data shown in Figure 6-8 in the timer/
event counter mode register.
Figure 6-8. Timer/Event Counter Mode Register Setting (Event Counter Mode)
ETMM
7
6
5
4
3
2
1
0
0
0
0
0
0
1
1
0
CI input count
Free running
cleared after
full count
External pulses input to the CI pin are synchronized with the internal clock, and ECNT counts up on their falling
edge.
The pulse width of the pulses input to the CI pin must be at least 500 ns (at 12 MHz operation); pulses of 250
ns or less in width are regarded as noise signals and are not counted.
The count value can be read at any time by software.
When the timer/event counter mode register is set as shown in Figure 6-8, if ECNT counts up to FFFFH the OV
(Overflow) flag is set and the count starts again from 0000H. The OV flag does not have an interrupt function but
can be tested in the program by means of a skip instruction (SKIT or SKNIT).
When the external event count reaches the value set in ETM0/ETM1, and internal interrupt (INTE0/INTE1) is
generated.
Figure 6-9. Event Counter Mode Operation
Internal
clock
( φ 3)
CI input
Internal
signal
ECNT input
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TIMER/EVENT COUNTER FUNCTIONS
6.3.3 Frequency measurement mode
In this mode the frequency of the external pulses input to the CI pin is measured. Since the external pulses in
the period (basic time) during which the timer output (TO) is high are counted in this mode, the timer needs to be
started beforehand.
After first clearing ECNT, the operation is started by setting the data shown in Figure 6-10 in the timer/event counter
mode register.
Figure 6-10. Timer/Event Counter Mode Register Setting (Frequency Measurement Mode)
ETMM
7
6
5
4
3
2
1
0
0
0
0
0
1
0
1
1
CI input count while TO is high
ECNT cleared on fall of TO
ECNT counts the external pulses input to the CI pin while the timer output (TO) is high. When the timer output
falls, the ECNT contents are transferred to the timer/event counter capture register (ECPT), ECNT is cleared, and
an interrupt (INTEIN) is generated (see Figure 6-11).
Since the input to ECNT is the CI input while TO is high, ECNT is cleared and the interrupt generated by the fall
of TO (see 6.1 (6) Clear control circuit and (7) Interrupt control circuit).
Figure 6-11. Frequency Measurement Mode Operation
Timer
output
(TO)
CI input
ECNT input
INTEIN
Interrupt acknowledgment
ECNT contents transferred to ECPT
ECNT cleared
93
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TIMER/EVENT COUNTER FUNCTIONS
6.3.4 Pulse width measurement mode
The pulse width measurement mode is used to measure the high-level width of external pulses input to the CI
pin.
After first clearing ECNT, the operation is started by setting the data shown in Figure 6-12 in the timer/event counter
mode register (ETMM).
Caution The timer/event counter count should be started while TO is low (ECNT input is masked). If the
timer is started when TO is high, the counter contents should be read by the second INTEIN
onward after the timer is started.
Figure 6-12. Timer/Event Counter Mode Register Setting (Pulse Width Measurement Mode)
ETMM
7
6
5
4
3
2
1
0
0
0
0
0
1
0
0
1
φ 12 Count while CI input is high
Cleared on fall of CI input
When the CI input rises, the internal clock (φ12) is supplied to ECNT and the count is started. ECNT continues
the internal clock while the CI input is high. When the CI input falls, the internal clock supply to ECNT is stopped,
the ECNT contents are transferred to the ECPT register, ECNT is cleared, and an internal interrupt (INTEIN) is
generated (see Figure 6-13). The transfer of the ECNT contents to the ECPT register, clearing of ECNT and interrupt
generation are performed on the fall of the CI input (see 6.1 (2) Timer/event counter capture register (ECPT),
(6) Clear control circuit and (7) Interrupt control circuit).
In the pulse width measurement mode both the high-level and low-level width of pulses input to the CI pin must
be at least 16 states (4 µs at 12 MHz operation); if less than 12 states, ECNT contents will not be transferred to the
ECPT register and ECNT will not be cleared.
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CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
Figure 6-13. Pulse Width Measurement Mode Operation
Internal
clock
(φ 12)
CI input
Internal
signal 1
ECNT input
Internal
signal 2
INTEIN
Interrupt acknowledgment
ECNT contents transferred
to ECPT
ECNT cleared
6.3.5 Programmable rectangular-wave output mode
In the programmable rectangular-wave output mode, programmable rectangular waves can be output to two
independent outputs (CO0 and CO1).
The same operations are performed for both CO0 and CO1: Here, programmable rectangular-wave output for
the CO0 output is described.
After first clearing ECNT, the count value is set in ETM0 and ETM1. Next, the data shown in Figure 6-14 is set
in the timer/event counter output mode register (EOM) to initialize the output control circuit and specify the operation.
The data shown in Figure 6-15 is set in the timer/event counter mode register and timer/event counter operation
is started.
Figure 6-14. Timer/Event Counter Output Mode Register Setting
EOM
7
6
5
4
3
2
1
0
0
0
0
0
1
0
1
0
No operation
LV0 level inversion enabled
LV0 set
95
CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
Figure 6-15. Timer/Event Counter Mode Register Setting (Programmable Rectangular-Wave Output Mode)
ETMM
7
6
5
4
3
2
1
0
0
0
1
1
1
1
0
0
Internal clock (φ 12) count
ECNT cleared by match of ECNT and
ETM1 contents
LV0 level output by match of ECNT and
ETM0 contents or ECNT and ETM1 contents
In the same way as in the interval timer mode, ECNT counts up every φ12 and the respective comparator compares
the ECNT count with the ETM0/ETM1 contents, and if a match is detected, generates a match signal (CP0/CP1) and
an interrupt (INTE0/INTE1). In response to the match signal, the output control circuit outputs the contents of the
level F/F (LV0) to the CO0 pin and inverts the LV0 contents.
Only in the event of a match between ECNT and ETM1, the ECNT contents are cleared and the count starts again
from 0000H. Thus a rectangular-wave output is obtained from CO0 with a pulse width equal to the count time
determined by the count value set in ETM0 and ETM1 (see Figure 6-16).
Internal interrupts can be disabled by setting (1) the MKE0/MKE1 bits of the interrupt mask register (MKL).
Rectangular-wave output from the CO1 pin is implemented in the same way as square-wave output from the CO0
pin by changing the mode register setting.
Figure 6-16. Programmable Rectangular-Wave Output Mode Operation
Internal
clock
(φ 12)
m
0
n0
m
n0
CP0
CP1
CO0
Start
Remark
ETM0=m
ETM1=n
96
(m < n: m, n count value)
ECNT clearance
ECNT clearance
CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
6.3.6 Timer/event counter program examples
Two examples of timer/event counter programs are given here, for programmable rectangular-wave output and
single-pulse output synchronized with the fall of the CI input.
(1) Programmable rectangular-wave output
The programmable rectangular-wave output example outputs a rectangular-wave from the CO0 pin as shown
in Figure 6-16. In this example the low-level width is 200 µs and the high-level width, 300 µs (at 12 MHz
operation).
The operation flow is shown below.
INIT
Timer/event counter
initialization
<a>
Port C
initialization
<b>
Count value
setting
<c>
Timer/event counter
mode setting
<d>
Rectangular-wave output to CO0
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TIMER/EVENT COUNTER FUNCTIONS
<a> The timer/event counter ECNT is cleared and CO0 output is driven low. To drive the CO0 output low,
LV0 is reset and that level is output to CO0.
Figure 6-17. Timer/Event Counter Mode Register Setting (Programmable Rectangular-Wave Output:
ECNT Clear, CO0 Output Reset)
ETMM
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
Clear and stop ECNT
EOM
7
6
5
4
3
2
1
0
0
0
0
0
0
1
1
1
Output of LV0 contents
LV0 level inversion enabled
LV0 reset
<b> The PC6 pin of port C is set as CO0 output.
Figure 6-18. Port C Setting (Programmable Rectangular-Wave Output)
MCC
7
6
5
4
3
2
1
0
×
1
×
×
×
×
×
×
PC6 as CO0 output
<c> To determine the low-level width and cycle of the rectangular-wave to be output to the CO0 pin, 00C8H
(low level=200 µs) is set in ETM0 (timer/event counter REG0) and 01F4H (cycle=500 µs) is ETM1 (at
12 MHz operation).
<d> Timer/event counter operation setting is performed by the timer/event counter mode register (ETMM).
Settings are as follows: An internal clock (φ12) as the ECNT input clock, a match between ECNT and
ETM1 as the ECNT clear mode, and a match between ECNT and ETM0 or between ECNT and ETM1
as the CO0 output timing. Timer/event counter operation is started by setting the timer/event counter
mode register.
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CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
Figure 6-19. Timer/Event Counter Mode Register Setting (Programmable Rectangular-Wave Output:
ECNT Operation Setting)
ETMM
7
6
5
4
3
2
1
0
0
0
1
1
1
1
0
0
ECNT input clock:
Internal clock (φ 12)
ECNT clear mode: Match between
ECNT and ETM1
CO0 output timing: Match between
ECNT and ETM0, or
match between
ECNT and ETM1
<e> LV0 is set so that a high-level signal will be output to the CO0 pin by the first comparator match signal
(CP0).
;***TIMER/EVENT COUNTER INITIALIZATION*******
INIT
: MVI
A, 00H
MOV
ETMM,A
; Clear timer/event counter
MVI
EOM, 07H
; Initialize counter output 0
MVI
A, 40H
; PC6 : CO0
MOV
MCC, A
; Set Port C mode control
LXI
EA, 00C8H
; Low level : 200 µs at 12 MHz
DMOV
ETM0, EA
; Set count value
LXI
EA, 01F4H
; High level : 300 µs at 12 MHz
ETM1, EA
; Set count value
DMOV
START : MVI
A, 3CH
MOV
ETMM, A
; Set timer/event counter mode & start
ORI
EOM, 08H
; Set LV0
<a>
<b>
<c>
<d>
<e>
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CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
(2) Single pulse output
In single pulse output, as shown in Figure 6-20, a pulse is output to the CO0 pin a specific time after the fall
of the CI input. In this program example a pulse with a high-level width of 200 µs is output 100 µs after the
fall of the CI input (at 12 MHz operation).
Figure 6-20. Single Pulse Output
CI
CO0
100 µ s
INTEIN
200 µs
INTE1
The following are required in order to perform this operation: An initialization program, a service routine to
handle internal interrupts (INTEIN) generated by the fall of the CI input, and a service routine to handle internal
interrupts (INTE1) generated by a match between the contents of ECNT and ETM1.
First, the initialization routine will be described. The operation flow is shown below.
INITIAL
100
Timer/event counter
initialization
<a>
Port C
initialization
<b>
Interrupt mask register
mode setting
<c>
Timer/event counter
mode setting
<d>
CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
<a> The timer/event counter ECNT is cleared, CO0 output is driven low, and LV0 is set. This is done in the
same way as in step <a> of (1) "programmable rectangular-wave output".
<b> The PC5 in of port C is set as CI input, and the PC6 pin as CO0 output.
Figure 6-21. Port C Setting (Single Pulse Output)
MCC
7
6
5
4
3
2
1
0
×
1
1
×
×
×
×
×
PC5 as CI input
PC6 as CO0 output
<c> Internal interrupt (INTEIN) masking is released by means of the interrupt mask register (MKL).
Internal interrupts (INTAD) with the same priority as INTEIN must be masked by the interrupt mask
register (MKH).
Figure 6-22. Interrupt Mask Register Setting (Single Pulse Output: INTEIN Mask Release)
MKL
7
6
5
4
3
2
1
0
0
×
×
×
×
×
×
×
INTEIN masking released
MKH
7
6
5
4
3
2
1
0
×
×
×
×
×
×
×
1
INTAD masking
<d> Timer/event counter operation setting is performed by the timer/event counter mode register (ETMM).
The following settings are made in the timer/event counter mode register (ETMM): An internal clock
(φ12) as the ECNT input clock, and free running as the ECNT clear mode.
Timer/event counter operation is started by setting the timer/event counter mode register.
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TIMER/EVENT COUNTER FUNCTIONS
Figure 6-23. Timer/Event Counter Mode Register Setting (Single Pulse Output: ECNT Operation Setting)
ETMM
7
6
5
4
3
2
1
0
0
0
0
0
0
1
0
0
ECNT input clock: Internal clock (φ 12)
ECNT clear mode: Free running
An example of the initialization program is shown below.
;***TIMER/EVENT COUNTER INITIALIZATION******
INIT
: MVI
A, 00H
MOV
ETMM, A
; Clear timer/event counter
MVI
EOM, 05H
; Initialize counter output 0
MVI
A, 60H
; PC5 : CI, PC6 : CO0
MOV
MCC, A
; Set port mode control
ANI
MKL, 7FH
; INTEIN enable
A, 04H
; ECNT free running
ETMM, A
; Set timer/event counter mode & start
START : MVI
MOV
<a>
<b>
<c>
<d>
After initialization, when the CI input falls the value of the free running ECNT (the value at the time of the CI input
fall) is latched in the ECPT (TIMER/EVENT COUNTER CAPTURE REG) and an internal interrupt (INTEIN) is generated.
The operation flow for the servicing of this interrupt is shown below.
EINSV
Count value
setting
<a>
Timer/event counter
mode setting
<b>
Interrupt mask register
setting
<c>
RETI
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CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
<a> 100 µs after the fall of the CI input, a pulse with a width of 200 µs is output to the CO0 pin, and thus
the value obtained by adding 0064H (100 µs) to the ECPT value is set in ETM0, and the value obtained
by adding 012CH (300 µs) to the ECPT value is set in ETM1 (at 12 MHz operation).
<b> CO0 output timing is specified by setting the timer/event counter mode register (ETMM) to a match
between ECNT and ETM0 or between ECNT and ETM1.
The ECNT input clock and ECNT clear mode are kept as they are.
LV0 of the output control circuit is set and LV0 level inversion enabled by setting the timer/event counter
output mode register (EOM).
Figure 6-24. Timer/Event Counter Mode Register Setting (Single Pulse Output:
CO0 Output Timing Setting)
ETMM
7
6
5
4
3
2
1
0
0
0
1
1
0
1
0
0
ECNT input clock: Internal clock (φ12)
ECNT clear mode: Free running
CO0 output timing: Match between
ECNT and ETM0, or
match between
ECNT and ETM1
EOM
7
6
5
4
3
2
1
0
0
0
0
0
1
0
1
0
LV0 level inversion enabled
LV0 set
<c> Masking of interrupts (INTE1) generated by a match between ECNT and ETM1 is released by setting
the interrupt mask register (MKL). INTE0 interrupts, which have the same priority as INTE1 interrupts,
must be masked.
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CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
Figure 6-25. Interrupt Mask Register (MKL) Setting (Single Pulse Output: INTE1 Mask Release)
MKL
7
6
5
4
3
2
1
0
×
0
1
×
×
×
×
×
INTE0 masking
INTE1 masking released
The INTEIN interrupt service program is shown below.
A JMP EINSV instruction must be stored in the INTEIN interrupt start address (0020H).
;***TIMER/EVENT COUNTER SERVICE********
EINSV : EXA
; Save accumulator
EXX
; Save register
DMOV
EA, ECPT
LXI
B, 0064H
DADD
EA, B
; Low level : 100 µs at 12 MHz
DMOV
ETM0, EA
; Set count value
LXI
B, 00C8H
DADD
EA, B
; High level : 200 µs at 12 MHz
DMOV
ETM1, EA
; Set count value
MVI
A, 34H
MOV
ETMM, A
ORI
EOM, 0AH
; Set level F/F, inversion enable
ANI
MKL, 0BFH
; INTEIN, INTE1 enable
<a>
<b>
EXX
; Recover register
EXA
; Recover accumulator
<c>
EI
RETI
After the interrupt service program by INTEIN, an internal interrupt (INTE1) is generated when the contents of
ECNT and ETM1 are the same.
The flowchart of this interrupt processing is shown below.
104
CHAPTER 6
TIMER/EVENT COUNTER FUNCTIONS
EISV
Timer/event counter
mode setting
<a>
Interrupt mask
register setting
<b>
RETI
<a>
CO0 output operation is stopped by setting the timer/event counter output mode register (EOM).
<b>
INTE1 interrupts are masked (disabled) by setting the interrupt mask register (MKL).
;***TIMER/EVENT COUNTER SERVICE*********
E1SV : MVI
EOM, 00H
ORI
MKL, 40H
<a>
; INTE1 disable
<b>
EI
RETI
105
[MEMO]
106
CHAPTER 7 SERIAL INTERFACE FUNCTIONS
The µPD78C18 is equipped with a serial interface which allows distributed processing and the connection of
various kinds of terminals. This serial interface has three operation modes; asynchronous mode, synchronous mode,
and I/O interface mode.
7.1 Serial Interface Configuration
As shown in Figure 7-1, the serial interface consists of three pins, the serial data input (RxD), serial data output
(TxD) and serial clock input/output (SCK); a transmission unit and reception unit each equipped with an 8-bit serial
register, a buffer register, and transmission/reception control; and a mode register which specifies the operation
mode.
Figure 7-1. Serial Interface Configuration
Internal bus
INTSR
Receive buffer
register (RXB)
Serial mode
register
Reception
control
INTST
Serial register
(P → S)
Serial register
(S → P)
PC1/RxD
Transmit buffer
register (TXB)
ER
Transmission
control
φ 24
PC2/SCK
φ 384
TO output
SK1, 2
PC0/TxD
Remark
φ24=fXX × 1
24
φ384=fXX × 1
384
fXX: Oscillator frequency (MHz)
107
CHAPTER 7
SERIAL INTERFACE FUNCTIONS
(1) Transmission unit
(a) Serial register (P → S)
This register converts parallel data transferred from the transmit buffer register into serial data and
transmits it from the TxD pin.
(b) Transmit buffer register
This register is used to write the parallel data to be transmitted; when serial register data transmission
ends the contents of the transmit buffer register are transferred to the serial register. When the buffer
register becomes empty an interrupt request (INTST) is generated.
(c) Transmission control circuit
This circuit performs all control required for serial data transmission, and generates related internal
signals.
(2) Reception unit
(a) Serial register (S → P)
This register converts serial data input from the RxD pin into parallel data and transfers it to the receive
buffer register.
(b) Receive buffer register
Parallel data converted by the serial register is transferred to this register. When the receive buffer
register becomes full an interrupt request (INTSR) is generated.
(c) Reception control circuit
This circuit performs all control required for serial data reception, and also sets the ER flag if a serial error
is generated. The ER flag can be checked by an SKIT instruction. Resetting the ER flag does not affect
the receive buffer.
(3) Serial mode registers
These are two 8-bit registers which control the operating mode of the serial interface (see 7.2 Serial Mode
Registers for details).
As the serial interface has a serial register and a buffer for send and receive operations, it can send and receive
data independently (full duplex double buffer method transmitter/receiver). However, as the serial clock (SCK) is
used for both send and receive operations, a half duplex method is employed in the synchronous mode and the I/O
interface mode.
108
CHAPTER 7
SERIAL INTERFACE FUNCTIONS
7.2 Serial Mode Registers
These are two 8-bit registers which specify the serial interface operation mode, serial clock, data format, etc.
7.2.1 Serial mode high register (SMH)
The individual bits of the serial mode high register are used to specify the operating mode as shown below. The
configuration of this register is shown in Figure 7-2.
(1) SK1, SK2 (bits 0 & 1)
These bits specify whether an internal clock or external clock is used as the serial clock (SCK).
When an internal clock is specified as the serial clock, the serial clock value is determined by the following
expressions,
For internal clock (φ24)
SCK=
fXX
24
For internal clock (φ384)
SCK= fXX
384
For TO output used as internal clock
When the timer input clock is φ12
SCK=
fXX
24 × C
When the timer input clock is φ384
SCK=
fXX
768 × C
When the timer F/F input is φ3
SCK= fXX
6
where fXX is the oscillator frequency, SCK is the serial clock, and C is the timer count value:
When the timer F/F input is φ3 when the TO output is used as the internal clock, the clock can only be used
in asynchronous mode when the clock rate is 16 or 64.
109
CHAPTER 7
SERIAL INTERFACE FUNCTIONS
(2) TxE (bit 2)
This bit determines whether or not the operation is a transmit operation. When the TxE bit is reset (0) the
TxD pin is driven high and data transmission is not performed. When the TxE bit is set (1), data transmission
is enabled and if data has previously been written into the transmit buffer register, that data is output.
Alternatively, when data is written into the transmit buffer register, serial data is transmitted from the TxD
pin.
However, when the TxE bit is changed from the set (1) status to the reset (0) status, transmission is disabled
after the data in the serial register has been transmitted. Therefore, when there is data in both the transmit
buffer register and the serial register, transmission is disabled after the serial register data has been
transmitted, and the transmit buffer register data is retained without being transmitted. The data in the
transmit buffer register is transmitted as serial data when transmission is next enabled (TxE=1).
Thus, when transmission is to be disabled (TxE=0) after all transmit data has been transmitted, it is necessary
to check that the serial transmission interrupt request flag (INTFST) is set (1) and the transmit buffer register
is empty before executing the operation.
(3) RxE (bit 3)
Controls whether or not a receive operation is performed. When the RxE bit is reset (0), data reception is
not performed. When the RxE bit is set (1), data reception is enabled.
(4) SE (bit 4)
Controls whether or not search mode is entered in synchronous mode (set by SML).
When the SE bit is set (1), the serial register contents are transferred to the receive buffer register and a serial
reception interrupt (INTSR) is generated each time a data bit is received. When the SE bit is reset (0), the
serial register contents are transferred to the receive buffer register and a serial reception interrupt (INTSR)
is generated each time 8 data bits are received.
(5) IOE (bit 5)
Controls whether the synchronous mode or I/O interface mode is entered in the case of synchronous operation
(set by SML). The synchronous mode is selected when the IOE bit is reset (0), and the I/O interface mode
is selected when the IOE bit is set (1).
(6) TSK (bit 6)
This bit is used to start the serial clock when data is received using an internal clock in the I/O interface mode.
When the TSK bit is set (1) and the serial clock is started, this bit is automatically reset (0).
110
CHAPTER 7
SERIAL INTERFACE FUNCTIONS
The serial mode high register (SMH) is reset to 00H by RESET input and in the hardware STOP mode.
Figure 7-2. Serial Mode High Register (SMH) Format
SMH
7
6
5
4
3
2
1
0
0
TSK
IOE
SE
RxE
TxE
SK2
SK1
SCK selection
0
0
Internal clock (TO output)
0
1
Internal clock (φ 384)
1
0
Internal clock (φ 24 )
1
1
External clock
Transmission enable
0
Disable
1
Enable
Reception enable
0
Disable
1
Enable
Search mode
0
Disable
1
Enable
I/O interface mode
0
Disable
1
Enable
SCK trigger
0
Disable
1
Enable
111
CHAPTER 7
SERIAL INTERFACE FUNCTIONS
7.2.2 Serial mode low register (SML)
The individual bits of the serial mode low register are used to specify the operating mode as shown below. The
configuration of this register is shown in Figure 7-3.
(1) B1 & B2 (bits 0 & 1)
These bits determine asynchronous mode and synchronous operation switching and the data rate in the
synchronous mode. In the asynchronous mode the serial clock is divided by the clock rate specified by these
bits and used for data transfer.
For synchronous operation, the B1 and B2 bits are set to "00".
(2) L1 & L2 (bits 2 & 3)
These bits specify the number of bits comprising a character.
(3) PEN (bit 4)
This bit determines whether odd/even parity is added to the transfer data and whether an odd/even parity
check is made on the transfer data.
When the PEN bit is set (1), a parity bit is added to each character before transmission, and a parity check
is performed during reception; if a parity error is generated the error flag is set.
When the PEN bit is reset (0), parity addition and checking is not performed.
(4) EP (bit 5)
This bit controls whether odd or even parity is used. Even parity is used when the EP bit is set (1), and odd
parity when reset (0).
The EP bit is only valid when the PEN bit is set (1).
(5) S1 & S2 (bits 6 & 7)
These bits control the number of stop bits transmitted in the asynchronous mode.
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CHAPTER 7
SERIAL INTERFACE FUNCTIONS
Figure 7-3. Serial Mode Low Register (SML) Format
SML
7
6
5
4
3
2
1
0
S2
S1
EP
PEN
L2
L1
B2
B1
Clock rate
0
0
Synchronous operation
0
1
×1
1
0
× 16
1
1
× 64
Character length
0
0
Setting prohibited
0
1
Setting prohibited
1
0
7 bits
1
1
8 bits
Parity enable
0
Disable
1
Enable
Even parity generation/check
0
Odd
1
Even
Number of stop bits
0
0
Setting prohibited
0
1
1 bit
1
0
Setting prohibited
1
1
2 bits
The serial mode low register (SML) is set to 48H by RESET input and in the hardware STOP mode.
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7.2.3 Serial mode register initialization
The following procedure should be used for serial mode register initialization.
<1> Set the mode to be used in the SMH register while the TxE bit and RxE bit are both "0" (transmission
and reception disabled).
<2> Set the SML register.
<3> When the TO output is used as the serial clock, perform timer mode setting (unless the timer mode
has already been specified).
<4> Set the port C pins to be used for the serial interface to control mode.
<5> Enable transmission or reception by manipulating the SMH register.
7.3 Serial Interface Operation
The µPD78C18 serial interface has 3 operation modes: Asynchronous (start/stop) mode, synchronous mode, and
I/O interface mode.
Each of these modes is described below.
7.3.1 Asynchronous mode
In the asynchronous mode transmission/reception is performed by means of start/stop bits, with data bit
synchronization and character synchronization performed by means of the start bit.
When data transmission/reception is performed in this mode, the transmission/reception parameters (character
length, clock rate, number of stop bits odd/even parity, serial clock, transmission/reception enabling, etc.) are set
in the serial mode register (SMH and SML) as shown in Figure 7-4.
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Figure 7-4. Serial Mode Register Format in Asynchronous Mode (1/2)
SML
7
6
5
4
3
2
1
0
S2
S1
EP
PEN
L2
L1
B2
B1
Clock rate
0
1
×1
1
0
× 16
1
1
× 64
Character length
0
0
Setting prohibited
0
1
Setting prohibited
1
0
7 bits
1
1
8 bits
Parity enable
0
Disable
1
Enable
Even parity generation/check
0
Odd
1
Even
Number of stop bits
0
0
Setting prohibited
0
1
1 bit
1
0
Setting prohibited
1
1
2 bits
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Figure 7-4. Serial Mode Register Format in Asynchronous Mode (2/2)
SMH
7
6
5
4
3
2
1
0
0
0
0
0
RxE
TxE
SK2
SK1
SCK selection
0
0
Internal clock (TO output)
0
1
Internal clock (φ 384)
1
0
Internal clock (φ 24)
1
1
External clock
Transmission enable
0
Disable
1
Enable
Reception enable
116
0
Disable
1
Enable
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SERIAL INTERFACE FUNCTIONS
When an internal clock is specified as the serial clock (SCK), the data transfer rate is determined from the oscillator
frequency and the clock rate by the following expressions, where fXX is the oscillator frequency, N is the clock rate
(1, 16, 64), C is the timer count value, and B is the data transfer rate:
For internal clock (φ24)
B=
fXX
24 × N
For internal clock (φ384)
B=
fXX
384 × N
For TO output used as internal clock
When the timer input clock is φ12
B=
fXX
24 × N × C
When the timer input clock is φ384
B=
fXX
768 × N × C
When the timer F/F input is φ3
B=
fXX
6×N
When the timer F/F input is φ3 when the TO output is used as the internal clock, the clock can only be used when
the clock rate is 16 or 64.
When TIMER0 is used and the clock rate is 16, the set values of the timer mode register (TMM) and the serial
mode registers (SML, SMH) are as follows:
TMM : ×××00000B
SML : ××××××10B
SMH : 0000××00B
(×: Set by user)
When the TO output is specified as the internal clock and the input clock to the timer is used as the internal clock
(φ12), the timer count values shown in Table 7-1 are set to perform transmission/reception at data transfer rates of
110 to 9600 bps.
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Table 7-1. Timer Setting
Oscillator
Frequency (MHz)
Data
Transfer Speed
(bps)
7.3728
16
N
9600
C=
11.0592
64
2
16
—
C=
14.7456
C=
64
16
C=
64
3
—
4
C=
1
1
6
—
8
2
3
16
4
4800
4
2400
8
2
12
1200
16
4
24
6
32
8
600
32
8
48
12
64
16
300
64
16
96
24
128
32
150
128
32
192
48
256
64
110
175
44
262
65
370
88
C=
The data format in asynchronous mode is shown in Figure 7-5.
Figure 7-5. Asynchronous Data Format
INTSR/INTST generation
Marking
Start
bit
D0
D1
DN
Parity
bit
Stop
bit(s)
Note
Marking
1 or 2 bits
N=6, 7
Odd/even,
no parity
Note INTSR is generated by the first stop bit. INTST is generated by the first bit when there is only one stop
bit, and by the second bit when there are two stop bits.
(1) Data transmission
A transmit operation in the asynchronous mode is enabled by setting (1) the TxE bit of the serial data high
register (SMH).
When data is written to the transmit buffer register by the MOV TXB, A instruction and the previous data
transfer is terminated, the transmit buffer register contents are automatically transferred to the serial register.
The start bit (1 bit), the parity bit (odd/even, no parity) and the stop bit (s) (1 or 2 bits) are automatically added
to the data transferred to the serial register, and the data is then transmitted LSB-first from the TxD pin. When
the transmit buffer register becomes empty, a serial transmission interrupt (INTST) is generated.
Serial transmission interrupts are disabled by setting (1) the MKST bit of the interrupt mask register (MKH).
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When the transmit buffer register is full, when the next data write is performed the previous data is corrupted.
Therefore, when writing data to the transmit buffer register, it is necessary to check that the serial
transmission interrupt request flag (INTFST) is set (1) and the transmit buffer register is empty before
executing the operation.
When the TxE bit is "0" or when the serial register contains no data to be transmitted, the TxD pin assumes
the mark status (1).
Transmit data is transmitted on the falling edge of SCK from the TxD pin with a clock rate of serial clock × 1,
× 1 or × 1 .
64
16
The maximum data transfer rate in transmission is set as shown in Table 7-2 according to SCK and the clock
rate at 15 MHz operation.
Caution When TxE changes from 0 to 1 (transmission enabled) while the transmit buffer register is
empty, INTST is generated.
Table 7-2. Maximum Data Transfer Rate at Transmission
SCK
Internal Clock
External Clock
SCK
Data Transfer Rate
SCK
Data Transfer Rate
×1
625 kHz
625 kbps
1.25 MHz
1.25 Mbps
×16
2.5 MHz
156 kbps
2.5 MHz
156 kbps
Clock Rate
×64
39.1 kbps
39.1 kbps
(2) Data reception
A receive operation is enabled by setting (1) the RxE bit of the serial mode high register (SMH).
The start bit is confirmed by detecting a low level RxD input and then detecting the low level again after a
1/2 bit time. This is effective in preventing errors due to noise in the mark state. Reception is performed
by sampling the center of the subsequent character bits, parity bit and stop bit.
Remark The 1/2 bit timer for each clock rate is as follows:
× 1 : 1/2 SCK clock pulse
× 16 : 8.5 SCK clock pulse
× 64 : 32.5 SCK clock pulse
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When the prescribed data is input from the RxD pin to the serial register, data is transferred to the receive
buffer register. When the receive buffer register becomes full, an interrupt request (INTSR) is generated.
Serial reception interrupts are disabled by setting (1) the MKSR bit of the interrupt mask register (MKH).
An odd/even parity check is made in data reception (when the PEN bit=1). If there is a mismatch (parity error),
the stop bit is low (framing error), or the next data is transferred to the receive buffer when the receive buffer
is full (overrun error), the error flag is set.
However, because no error interrupt feature is provided, testing must be performed by skip instructions (SKIT
or SKNIT) in the program.
When an error is generated, also, an overrun error will be generated again in the next receive operation if
the RXB data is not read.
The maximum data transfer rate in reception is set as shown in Table 7-3 according to SCK and the clock rate
at 15 MHz operation
Table 7-3. Maximum Data Transfer Rate at Reception
SCK
Internal Clock
External Clock
SCK
Data Transfer Rate
SCK
Data Transfer Rate
× 1Note 2
625 kHz
625 kbps
830 kHz
1.25 MHz
830 kbps
1.25 MbpsNote 1
× 16
2.5 MHz
156 kbps
2.5 MHz
156 kbps
Clock Rate
× 64
39.1 kbps
39.1 kbps
Notes 1. When data is received at transfer rates between 830 kbps and 1.25 Mbps,
2 stop bits are necessary.
2. At the × 1 clock rate, RxD must input a signal synchronized with SCK.
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7.3.2 Synchronous mode
In the synchronous mode, character synchronization is implemented by means of synchronization characters, and
bit synchronization by means of the serial clock.
In this mode, data is transferred with a fixed character length of 8 bits with no parity bit. The serial mode register
settings are therefore as shown in Figure 7-6.
Figure 7-6. Serial Mode Register Format in Synchronous Mode
SML
7
6
5
4
3
2
1
0
0
0
0
0
1
1
0
0
Synchronous operation
Fixed 8-bit character length
Parity disable
SMH
7
6
5
4
3
2
1
0
0
0
0
SE
RxE
TxE
SK2
SK1
SCK selection
0
0
Internal clock (TO output)
0
1
Internal clock (φ 384)
1
0
Internal clock (φ 24 )
1
1
External clock
Transmission enable
0
Disable
1
Enable
Reception enable
0
Disable
1
Enable
Search mode
0
Disable
1
Enable
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In the synchronous mode, as shown in Figure 7-7, the transmit data has a fixed character length of 8 bits with
no parity bit, and is transferred LSB-first on the falling edge of the serial clock (SCK). Receive data is input on the
rising edge of SCK.
Figure 7-7. Synchronous Mode Timing
SCK
6
Serial data
7
MSB
0
1
2
3
4
5
LSB
6
7
MSB
0
1
2
LSB
1 data transfer
(1) Data transmission
A transmit operation in the synchronous mode is enabled by setting (1) the TxE bit of the serial mode high
register (SMH).
When data is written to the transmit buffer register by a MOV TXB, A instruction and the previous data transfer
is terminated, the transmit buffer register contents are transferred to the serial register, converted into serial
data, and transmitted LSB-first from TxD in synchronization with the falling edge of SCK. Serial data is
transmitted at the same rate as SCK.
When data is transferred from the transmit buffer register to the serial register and the transmit buffer register
becomes empty, an interrupt request (INTST) is generated.
Serial transmission interrupts are disabled by setting (1) the MKST bit of the interrupt mask register.
When the TxE bit is "0" or when the serial register contains not data to be transmitted, the TxD pin assumes
the mark status (1).
However, when an external clock is used, the mark status is assumed after output of a 1-bit low-level pulse.
The maximum data transfer rate in transmission is 625 kbps when an internal clock is used as SCK, and 1.25
Mbps when an external clock is used (at 15 MHz operation).
(2) Data reception
A receive operation in the synchronous mode is enabled by setting (1) the RxE bit of serial mode high register
(SMH). Receive data is input on the rising edge of SCK.
Two kinds of receive operations are available in the synchronous mode and can be controlled by the SE bit
of the serial mode high register (SMH).
When the SE bit is set (1), the search mode is set. Each time one bit is sent to the MSB of the serial register
from the RxD pin, the serial register contents are transferred to the receive buffer register and a serial
reception interrupt (INTSR) is generated. Since the µPD78C18 is not provided with a circuit for detecting
synchronization characters by hardware, it is necessary to detect the synchronization characters by software.
When a synchronization character is detected and reception is synchronized, the SE bit is reset (0).
Resetting (0) the SE bit sets the character reception mode. Each time 8-bit data is received, the serial register
contents are transferred to the receive buffer register and a serial reception interrupt (INTSR) is generated.
Serial reception interrupts are disabled by setting (1) the MKSR bit of the interrupt mask register (MKH).
The maximum data transfer rate in reception is 625 kbps when an internal clock is used as SCK, and 1.25
Mbps when an external clock is used (at 15 MHz operation).
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7.3.3 I/O interface mode
In the I/O interface mode, synchronization is implemented by the controlled serial clock, as with the serial data
transfer method of the µPD7801, µPD78C06A, etc.
In this mode, data is transferred/received with a fixed character length of 8 bits with no parity bit. The serial mode
register settings are therefore as shown in Figure 7-8.
Figure 7-8. Serial Mode Register Format in I/O Interface Mode
SML
7
6
5
4
3
2
1
0
0
0
0
0
1
1
0
0
Synchronous operation
Fixed 8-bit character length
Parity disable
SMH
7
6
5
4
3
2
1
0
0
TSK
1
0
RxE
TxE
SK2
SK1
SCK selection
0
0
Internal clock (TO output)
0
1
Internal clock (φ 384)
1
0
Internal clock (φ 24 )
1
1
External clock
Transmission enable
0
Disable
1
Enable
Reception enable
0
Disable
1
Enable
I/O interface mode
SCK trigger
0
Disable
1
Enable
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In the I/O interface mode, the transmit data (TxD) is transferred MSB-first on the falling edge of the serial clock
(SCK). Receive data (RxD) is input on the rising edge of SCK.
Figure 7-9. I/O Interface Mode Timing
SCK
0
Serial data
1
2
3
4
5
6
MSB
7
LSB
0
1
2
MSB
In this mode character synchronization is implemented using the controlled SCK (8 serial clock pulses).
An external clock or internal clock can be selected as SCK by means of the serial mode high register.
When an internal clock is used as SCK, the controlled clock (8 pulses per data item) is output from the SCK pin.
When an external clock is used as SCK, 8 clock pulses should be accurately supplied to SCK as the single data
item transfer (8-bit) unit by the control signal supply source.
Caution In the I/O interface mode, one pulse is output at low level from the TxD pin at the time of changing
from the transmit enable state to receive enable state (transmit disable).
(1) Data transmission
A transmit operation in the I/O interface mode is enabled by setting (1) the TxE bit of the serial mode high
register.
When data is written to the transmit buffer register by a MOV TXB, A instruction and the previous data transfer
is terminated, the transmit buffer register contents are transferred to the serial register. When SCK is an
internal clock, when the data is transferred to the serial register a controlled SCK (8 pulses for one data item)
is automatically generated and the transmit data is sent MSB-first on the SCK falling edge.
When an external clock is used, the transmit data is sent MSB-first on the falling edge of the controlled SCK
input to SCK.
In this mode, synchronization is implemented by means of a controlled SCK (8 serial clock pulses), and SCK
should be driven high except during a data transfer.
When the transmit buffer register becomes empty, a serial transmission interrupt (INTST) is generated.
Serial transmission interrupts are disabled by setting (1) the MKST bit of the interrupt mask register (MKH).
The maximum data transfer rate in transmission is 625 kbps when an internal clock is used as SCK, and 1.25
Mbps when an external clock is used (at 15 MHz operation).
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(2) Data reception
A receive operation in the I/O interface mode is enabled by setting (1) the RxE bit of the serial mode high
register (SMH), and receive data (RxD) is input to the serial register in order from MSB on the rising edge
of SCK.
When the serial register receives 8-bit data, the data is transferred from the serial register to the receive buffer
register and a serial reception interrupt (INTSR) is generated.
When SCK is an external clock, the data sent in synchronization with SCK is input to the serial register on
the rising edge of SCK.
When SCK is an internal clock, it must be started by setting (1) the TSK bit of the serial mode high register
(SMH).
Serial reception interrupts are disabled by setting (1) the MKSR bit of the interrupt mask register (MKH).
The maximum data transfer rate in reception is 625 kbps when an internal clock is used as SCK, and 660 kbps
when an external clock is used (at 15 MHz operation). The high-level width of the 8th SCK pulse must be
at least 6 states.
Caution 1. When fewer than 8 external clock pulses are input (in transmission)
The correction procedure is shown below for the case where fewer than 8 external clock
pulses are input when performing transmission/reception in the I/O interface mode using
external clock input.
(1)
TxE bit reset to "0"
(2)
Change MC register
(3)
(4)
: Disable transmission
MC (2) → set to "1"
: Set to input port
MC (0) → reset to "0"
: Outputs high level
PC (0) → set to "1"
: Set to output port
Change MMC register
MMC (2) → reset to "0"
: SCK pin set to port mode
MMC (0) → reset to "0"
: TxD pin set to port mode
Change SMH
SK1 = 0 or SK1 = 1
SK2 = 1
: Set to internal clock mode
SK2 = 0
(5)
MKST bit → set to "1"
(6)
INTFST flag → reset to "0"
(7)
TxE bit → set to "1"
: Mask INTST
: Enable transmission and start
output of remaining serial
register data
(8)
Test FST flag
: Wait until FST is set to "1"
(9)
SK1 & SK2 bits → set to "1"
: Set to external clock
(10) To initial setting of MCC, MC MKST
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Caution 2. When fewer than 8 external clock pulses are input (in reception)
(1)
RxE bit → reset to "0"
: Disable reception
(2)
MC (2) → set to "1"
: Set to input port
(3)
MMC (2) → reset to "0"
: SCK pin set to port mode
(4)
Change SMH
SK1 = 0 or SK1 = 1
SK2 = 1
: Set to internal clock mode
SK2 = 0
(5)
MKSR bit → set to "1"
(6)
INTFSR flag → reset to "0"
(7)
RxE bit → set to "1"
: Enable reception
(8)
SCK trigger bit → set to "1"
: Start internal clock and start
(9)
Test FSR flag
: Wait until FSR is set to "1"
: Mask INTSR
remaining control count
(10) SK1 & SK2 bits → set to "1"
: Set to external clock
(11) To initial setting of MCC, MC, RxE, MKSR
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7.3.4 Example of serial interface program
In the following example of serial interface programming, data is exchanged with a µPD71051 in the asynchronous
mode.
This example uses the following parameters: µPD78C18 oscillator frequency of 11.0592 MHz, TO output internal
clock used as the serial clock, 110 bps data transfer rate, clock rate of 16, 8-bit character length, 2 stop bits, and
even parity enabled.
An example of the system configuration is shown in Figure 7-10. Three lines are necessary for serial data transfer,
the TxD and RxD serial data input and output lines, and the CTS (clear to send) control line. In this example, PC7
is functions as the CTS control line which is used when the µPD78C18 receives data. As PC7 is in input port mode
from resetting until the mode is set, "1" is written to the PC7 output latch before it is pulled high with a pull-up resistor
and set as an output port.
Figure 7-10. Example of Serial Data Transfer System Configuration
µ PD78C18
VDD
µ PD71051
CTS
CTS(PC7)
TxD
RxDATA
RxD
TxDATA
Baud
rate
generator
TxCLK
RxCLK
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CHAPTER 7
SERIAL INTERFACE FUNCTIONS
(1) Initialization
The serial mode registers, timer, port C, etc., must be initialized in advance to allow µPD78C18 serial data
transmission/reception.
The operation flow is shown below.
Initialize
Set serial
interface mode
<a>
Initialize timer
<b>
Initialize port C
<c>
Enable
transmission
<d>
<a> The parameters required for serial data transmission/reception (character length, clock rate, number
of stop bits, odd/even parity, serial clock) are set in the serial mode registers.
Figure 7-11. Serial Mode Register Setting
SML
7
6
5
4
3
2
1
0
1
1
1
1
1
1
1
0
Clock rate: 16
Character length: 8 bits
Parity: Enabled
Odd/even parity: Even parity
Number of stop bits: 2 bits
SMH
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
Serial clock: Internal clock
(TO output)
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<b> Since the timer TO output is being used as the serial clock (SCK), setting of the timer count value and
timer operation is performed. As an oscillator frequency of 11.0592 MHz, data transfer rate of 110 bps
and clock rate of 16 are used here, the count value is found from Table 7-1 or the following expression
to be 262.
C=
fXX
fXX
24 × N × B
: Oscillator frequency
N : Clock rate
B : Data transfer rate
C : Count value
Since the count value is greater than 255 (FFH), TIMER0 and TIMER1 are cascaded: 131 (83H) is set in TM0
(timer register) and 2 (02H) in TM1. Since TIMER0 and TIMER1 are cascaded, the timer mode register (TMM)
settings are as shown in Figure 7-12.
Figure 7-12. Timer Mode Register Setting
TMM
7
6
5
4
3
2
1
0
0
1
1
0
0
0
0
1
TIMER1 match signal
as timer F/F input
TIMER0 count input = φ 12
TIMER0 count-up
TIMER0 match signal
as TIMER1 count input
TIMER1 count-up
<c> Port C settings are performed as follows: PC0 as TxD pin, PC1 as RxD pin, PC7 as output port, and
PC7 set to output a high-level signal.
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Figure 7-13. Port C Setting (Serial Interface)
MCC
7
6
5
4
3
2
1
0
0
×
×
×
×
×
1
1
PC0 set as TxD pin
PC1 set as RxD pin
PC7 set as input/output port
PC
7
6
5
4
3
2
1
0
1
×
×
×
×
×
×
×
PC7 output latch "1"
MC
7
6
5
4
3
2
1
0
0
×
×
×
×
×
×
×
PC7 output port
When SCK of the µPD78C18 is output off chip or SCK is input from off chip, the PC2 pin can be used as the SCK
input/output pin by setting the MCC register.
<d> The TxE bit of the serial mode high register (SMH) is set (1), enabling transmission.
Figure 7-14. Serial Mode High Register (SMH) Setting (Serial Interface: Transmission Enable)
7
SMH
6
5
4
3
2
1
0
1
Previous status
Transmission enable
Previous status
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SERIAL INTERFACE FUNCTIONS
The initialization program is shown below.
;*****SERIAL INTERFACE INITIALIZATION*******
SINIT : MVI
SMH, 00H
; Internal serial clock (TO)
MVI
A, 0FEH
; × 16, even parity, 8 bit character, 2 stop bit
MOV
SML, A
; Set serial mode
MVI
A, 83H
;
MOV
TM0, A
; Set timer register
MVI
A, 02H
; Baud rate 110 bps
MOV
TM1, A
;
MVI
TMM, 61H
; Set timer mode & start
MVI
A, 07H
; Set port C mode control
MOV
MCC, A
; TxD, RxD, SCK available
ORI
PC, 80H
; PC7 output latch-1
MVI
A, 00H
; Initialize port C
MOV
MC, A
; Port C output mode
ORI
SMH, 04H
; Transmit enable
<a>
<b>
<c>
<d>
(2) µPD78C18 data transmission
The following example shows a subroutine which performs on-byte transmission of the accumulator (A)
contents as serial data. In this example operation by means of an interrupt (INTST) is not used, and serial
data transmission is performed by testing the interrupt request flag (INTFST). The operation flow is shown
below.
TRNS
N
INTFST = 1
?
<a>
Y
TXB ← A
<b>
RET
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<a> The interrupt request flag (INTFST) is tested to determine whether or not data can be written to the
transmit buffer (TXB).
<b> The accumulator contents are transferred to the transmit buffer.
The data transmission routine is shown below. When data is transmitted from the µPD78C18, the µPD71051
must be in the reception enabled state.
;*****TRANSMIT SERVICE*************
TRNS : SKIT
FST
; Test FST, skip if FST=1
JR
TRNS
; Wait until FST=1
MOV
TXB, A
; Output transmit data
RET
<a>
<b>
; Return
(3) µPD78C18 data reception
For data reception, hardware interrupts (INTSR) are used. Initialization is therefore necessary beforehand,
including setting of the memory address used to store the receive data, the number of received bytes, the
interrupt mask register, etc. The operation flow is shown below.
RVEN
132
Set memory
address
<a>
Set number of
received bytes
<b>
Set interrupt
mask register
<c>
Enable reception
<d>
CTS (PC7) ← "0"
<e>
CHAPTER 7
SERIAL INTERFACE FUNCTIONS
<a> The memory address for storing the receive data is set in the HL register pair. The setting here is for
storage of the receive data in address 2000H onward.
<b> The number of receive data bytes is set in the B register. The setting here is for reception of 16 (0FH)
data bytes.
<c> The MKSR bit of the interrupt mask register (MKH) is reset (0), releasing masking of INTSR internal
interrupts. The interrupt mask flag for INTST interrupts which have the same priority as INTSR interrupts
is set (1), setting INTST interrupts as masked.
Figure 7-15. Interrupt Mask Register (MKH) Setting (Serial Interface: INTSR Mask Release)
MKH
7
6
5
4
3
2
1
0
0
0
0
0
0
1
0
1
INTAD masked
INTSR masking released
INTST masked
<d> The RxE bit of the serial mode high register (SMH) is set (1), enabling reception.
Figure 7-16. Serial Mode High Register (SMH) Setting (Serial Interface: Reception Enable)
7
SMH
6
5
4
3
2
1
0
1
Previous status
Reception enable
Previous status
<e> PC7 output is set to "0", activating CTS.
A program which performs the initialization required for reception is shown below.
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SERIAL INTERFACE FUNCTIONS
;*****RECEIVE ENABLE**********
RVEN : LXI
H, 2000H
;
Set data pointer (DP=2000H)
<a>
C, 0FH
;
Set data counter (DC=0FH)
<b>
MKH, 05H
;
INTST enable
<c>
ORI
SMH, 08H
;
Receive enable
<d>
ANI
PC, 7FH
;
CTS=0
<e>
MVI
EXX
ANI
Following the above settings, an INTSR internal interrupt is generated each time the prescribed data is received.
The operation flow of the interrupt service routine is shown below.
INTSR
Error?
Y
<a>
N
Error
processing
Store data
in memory
Buffer
full?
<b>
N
<c>
Y
CTS (PC7) ← 1
Disable reception
Set interrupt
mask register
<d>
<e>
<f>
RETI
<a> The receive data is checked for errors; if an error is found, control passes to the error handling routine.
Caution
If the RXB data is not read out when an error is generated an overrun error will be generated
again when the next receive operation is performed.
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CHAPTER 7
SERIAL INTERFACE FUNCTIONS
<b> The receive data is stored in the memory.
<c> A check is made to see if the data buffer is full; if it is not, control returns to the main routine.
<d> PC7 output is set to "1", inactivating CTS, and µPD71051 data transmission is stopped.
<e> The RxE bit of the serial mode high register (SMH) is reset (0), and the receive operation is stopped.
<f> The MKSR bit of the interrupt mask register (MKH) is set (1), disabling INTSR internal interrupts.
The interrupt service routine is shown below. Either this interrupt service routine must be stored starting at the
INTSR interrupt address (0028H), or else a JMP RECV instruction must be stored in that address.
;*****RECEIVE SERVICE*************
RECV : EXA
; Save accumulator
EXX
; Save register
SKNIT
ER
; Test ERflag, skip if ER=0
JMP
ERROR
; Jump ERROR routine
MOV
A, RXB
; Input received data
STAX
H+
; Store received data to memory
DCR
C
; Skip if buffer full
JR
REC0
;
ORI
PC, 80H
; CTS←1
ANI
SMH, 0F7H ; Receive disable
<e>
ORI
MKH, 02H
<f>
REC0 : EXX
EXA
; INTSR disable
<a>
<b>
<c>
<d>
; Recover register
; Recover accumulator
EI
; Enable interrupt
RETI
; Return
135
[MEMO]
136
CHAPTER 8 ANALOG/DIGITAL CONVERTER FUNCTIONS
The µPD78C18 incorporates a high-precision 8-bit A/D converter with 8 analog inputs which uses the successive
approximation method, and four conversion result registers (CR0 to CR3) to hold the conversion results. The provision
of a scan mode and select mode for analog input selection minimizes the software overhead.
8.1 Analog/Digital Converter Configuration
The A/D converter consists of an input circuit, series resistance string, voltage comparator, successive approximation
logic, and registers CR0 to CR3 (see Figure 8-1).
The 8 analog inputs are multiplexed on the chip, and are selected by the specification of the A/D channel mode
register (ANM).
The selected analog input is sampled by the sampling & hold circuit and becomes one of the voltage comparator
inputs. The voltage comparator amplifies the difference between the analog input and the voltage tap of the series
resistance string.
The series resistance string is connected between the A/D reference voltage pin (VAREF) and the A/D ground (AVSS),
and consists of a total of 257 resistors comprising 255 equal resistors and two resistors equal to half that value to
provide 256 voltage steps between the two pins.
The series resistance string voltage tap is selected by the tap decoder. This decoder is driven by the 8-bit
successive approximation register (SAR).
One bit of the SAR is set at a time starting from the most significant bit (MSB) until the value of the series resistance
string voltage tap matches the voltage value of the analog input. That is, when conversion starts the MSB of the
SAR is set (1), and the series resistance string voltage tap is made 1/2 VAREF and is compared with the analog input.
If the analog input is greater than 1/2 VAREF, the MSB of the SAR remains set; if smaller than 1/2 VAREF, the MSB is
reset and the operation proceeds to comparison with the next upper bit after the MSB reset. Here, (i.e. for bit 7),
the series resistance string voltage tap is made 3/4 VAREF or 1/4 VAREF and is compared with the analog input. The
comparison process continues this way up to the least significant bit of the SAR (binary search method).
When the 8-bit comparison ends the SAR contains the valid digital result, and this result is serially latched into
registers CR0 to CR3.
When the A/D conversion result has been latched into all the registers, CR0 to CR3, and INTAD A/D conversion
termination interrupt is generated.
The A/D converter has independent power supply pins (AVDD and AVSS), and the effects of power supply fluctuations
and system noise can be minimized by supplying a stable power supply to these pins.
The A/D converter can also vary the voltage range for conversion by varying VAREF. and the A/D converter operation
can be controlled by inputting a low-level signal to VAREF.
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ANALOG/DIGITAL CONVERTER FUNCTIONS
Figure 8-1. A/D Converter Block Diagram
AN0
Sampling & hold
AN2
AN3
AN4
AN5
Input circuit
AN1
Series resistance
string
AN6
VAREF
R/2
AN7
Tap decoder
R
Comparator
A/D channel mode
register (8)
8
SAR (8)
Internal bus
8
R/2
AVSS
Control
From VAREF
8
AVDD
8
8
8
8
CR0 (8)
CR1 (8)
CR2 (8)
CR3 (8)
8
8
8
8
Internal bus
Caution A capacitor should be connected to the analog input pins (AN7 to AN0) and the reference voltage
input pin (VAREF) to prevent errors due to noise. A voltage outside the range from AVSS to VAREF
should not be applied to any of the pins AN7 to AN0 which are not used or which use an edge
detection function, as this will adversely affect the conversion precision. An effective means of
noise protection in this case is clamping with a diode with a small VF such as Schottky diode.
In addition, the impedance of the analog signal input source and the reference voltage input
source should be as small as possible.
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CHAPTER 8
ANALOG/DIGITAL CONVERTER FUNCTIONS
VDD
Analog input
ANn
100~
1000 pF
µ PD78C18
VDD
Reference voltage
input
VAREF
100~
1000 pF
139
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ANALOG/DIGITAL CONVERTER FUNCTIONS
8.2 A/D Channel Mode Register (ANM)
This register controls A/D converter operations. As shown in Figure 8-2, bit 0 (MS) of the A/D channel mode register
controls the operation mode, and bits 1 to 3 (ANI0 to ANI2) select the analog input for A/D conversion. Bit 4 (FR)
is used to maintain the optimum conversion speed; the conversion speed for one operation can be calculated by
means of the oscillator frequency and the FR bit using the following expressions, and is set as shown in Table 8-1.
FR=0: Conversion speed = 48 × 12/fXTAL (µs)
FR=1: Conversion speed = 36 × 12/fXTAL (µs)
fXTAL = Oscillator frequency (MHz)
Table 8-1. Conversion Speed Settings
Oscillator frequency
FR bit
Conversion speed
15 MHz
12 MHz
11 MHz
10 MHz
9 MHz
8 MHz
7MHz
0
0
0
0
1
1
1
38.4 µs
48 µs
52.4 µs
57.6 µs
48 µs
54 µs
61.7µs
Reading the contents of the A/D channel mode register allows the current conversion mode to be ascertained.
RESET input or hardware STOP mode resets the A/D channel mode register to 00H.
Writing to the ANM register initializes the A/D converter, stops the A/D conversion currently being performed,
and starts A/D conversion from the beginning in accordance with the contents written to ANM.
Thus if a write is performed on the ANM register after the INTFAD flag has been cleared, A/D conversion is started
in accordance with the written contents. Therefore, when the INTAD flag is set again, the post-change result is stored
in the CR registers (CR0 to CR3).
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CHAPTER 8
ANALOG/DIGITAL CONVERTER FUNCTIONS
Figure 8-2. A/D Channel Mode Register Format
ANM
7
6
5
4
–
–
–
FR
3
2
ANI2 ANI1
1
0
ANI0
MS
Operating mode specification
0
Scan mode
1
Select mode
Select mode
0
0
0
AN0
0
0
1
AN1
0
1
0
AN2
0
1
1
AN3
1
0
0
AN4
1
0
1
AN5
1
1
0
AN6
1
1
1
AN7
Scan mode
AN0-AN3
AN4-AN7
Conversion speed
0
192 states
1
144 states
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CHAPTER 8
ANALOG/DIGITAL CONVERTER FUNCTIONS
8.3 Analog/Digital Converter Operation
Either the scan mode or select mode can be specified for the A/D converter by means of the MS bit of the A/D
channel mode register (ANM).
8.3.1 Scan mode
In the scan mode, as shown in Figure 8-3, the A/D channel mode register (ANM) specifies either analog inputs
AN0 to AN3 (ANI2=0) or analog inputs AN4 to AN7 (ANI2=1).
Remark
Each of the analog inputs AN4 to AN7 has a function for detecting a falling edge and setting a test flag
which is unrelated to A/D conversion operations (see 9.2 External Interrupt Sampling).
Figure 8-3. A/D Channel Mode Register in Scan Mode
ANM
7
6
5
4
3
2
1
0
–
–
–
FR
ANI2
–
–
0
Scan mode
Analog input specification
0
AN0-AN3
1
AN4-AN7
Conversion speed
0
192 states
1
144 states
When the ANI2 bit of the A/D channel mode register is set to "0", analog inputs are selected in the order
AN0→AN1→AN2→AN3, and the A/D conversion value of each input is stored in the order CR0→CR1→CR2→CR3.
Similarly, when the ANI2 bit of the A/D channel mode register is set to "1", analog inputs are selected in the order
AN4→AN5→AN6→AN7, and the A/D conversion value of each input is stored in the order CR0→CR1→CR2→CR3.
When the conversion values have been stored in all four CR registers (CR0 to CR3), an INTAD internal interrupt
is generated.
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CHAPTER 8
ANALOG/DIGITAL CONVERTER FUNCTIONS
The A/D converter continues A/D conversion again from AN0 or AN4 irrespective of whether or not an interrupt
request has been acknowledged, and stores the A/D conversion results in order starting with CR0. This operation
continues until the A/D channel mode register is changed.
This mode allows A/D conversion of four analog inputs with a minimum of software.
Internal interrupts are disabled by setting (1) the MKAD bit of the interrupt mask register (MKH).
Figure 8-4. Outline of A/D Converter Operation Timing in Scan Mode
Sampling
ANM register
write
Sampling
Conversion
result write
to CR0 register
AN0 or AN4
conversion
operation
AN3 or AN7
conversion
operation
AN1 or AN2
conversion
operation
AN0 or AN4
conversion
operation
Sampling
Conversion
result write
to CR0 register
Conversion
result write
to CR3 register
Conversion
result write
to CR1 register
INTFAD flag setting
8.3.2 Select mode
In the select mode, as shown in Figure 8-5, the A/D channel mode register (ANM) specifies one of the analog
inputs AN0 to AN7.
Figure 8-5. A/D Channel Mode Register in Select Mode
7
6
5
4
–
–
–
FR
3
2
ANI2 ANI1
1
0
ANI0
1
Select mode
Analog input specification
0
0
0
AN0
0
0
1
AN1
0
1
0
AN2
0
1
1
AN3
1
0
0
AN4
1
0
1
AN5
1
1
0
AN6
1
1
1
AN7
Conversion speed
0
192 states
1
144 states
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CHAPTER 8
ANALOG/DIGITAL CONVERTER FUNCTIONS
A/D conversion is performed on the single analog input specified by the A/D channel mode register, and the A/
D conversion result is stored in the order CR0→CR1→CR2→CR3. When the conversion values have been stored
in all four CR registers (CR0 to CR3), an INTAD internal interrupt is generated.
The A/D converter continues A/D conversion again irrespective of whether or not an interrupt request has been
acknowledged, and stores the A/D conversion results in order starting with CR0. Thus the most recent conversion
values are always stored in the CR registers.
The A/D converter repeats the above operation until the contents of the A/D channel mode register are changed.
This mode holds the most recent conversion values for the selected analog inputs, and is useful for averaging
conversion values or preventing noise input, etc.
Internal interrupts are disabled by setting (1) the MKAD bit of the interrupt mask register (MKH).
Figure 8-6. Outline of A/D Converter Operation Timing in Select Mode
ANn
conversion
operation
Sampling
ANM
register
write
ANn
conversion
operation
Sampling
Conversion
result write
to CR0 register
ANn
conversion
operation
ANn
conversion
operation
Sampling
Conversion
result write
to CR1 register
ANn
conversion
operation
Sampling
Conversion
result write
to CR2 register
Conversion
result write
to CR3 register
Conversion
result write
to CR0 register
INTFAD flag setting
8.3.3 A/D converter operation control method
A/D converter operation can be stopped by controlling the VAREF input voltage. When a voltage of VIH1 or more
is input to the VAREF pin, the A/D converter starts the conversion operation and the conversion result is guaranteed
for VAREF=3.4 V to AVDD. If the VAREF pin input voltage is made VIL1 or less during the conversion operation, the A/D
converter conversion operation stops and CR0 to CR3 contents are undefined.
If the VAREF input voltage is changed for A/D converter to stop control, the A/D channel mode register (ANM) is
not affected. Thus, if the VAREF input voltage is increased to 3.4 V or more to reset the operating state from the stop
state, the A/D converter restarts its operation by storing a conversion value in CR0 in the mode in effect just before
it stopped.
If the VAREF input voltage level is changed, the edge detection function of inputs AN4 to AN7 is not affected.
Caution When VAREF is low, inputs AN0 to AN7 must be in the range from AVSS to AVDD.
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CHAPTER 8
ANALOG/DIGITAL CONVERTER FUNCTIONS
8.3.4 Input voltage and conversion results
Relationship between the analog input voltage input to the analog input pin (AN0 to AN7) and the A/D conversion
results (a value stored in CR0 to CR3) is shown in the following expression.
CR0 to CR3 = INT ( VIN × 256 + 0.5)
VAREF
or,
(CR0 to CR3 – 0.5) × VAREF ≤ VIN < (CR0 to CR3 + 0.5) × VAREF
256
256
Remark
INT (
)
: A function which returns an integer in parentheses
VIN
: Analog input voltage
VAREF
: VAREF pin voltage
CR0 to CR3 : CR0 to CR3 register value
Relationship between the analog input voltage and the A/D conversion results is shown in Figure 8-7.
Figure 8-7. Relationship Between Analog Input Voltage and A/D Conversion Results
255
254
A/D
conversion
results
(CR0 to CR3)
253
3
2
1
0
1
1
3
2
5
3
512 256 512 256 512 256
507 254 509 255 511
512 256 512 256 512
1
Input voltage/ VAREF
145
CHAPTER 8
ANALOG/DIGITAL CONVERTER FUNCTIONS
8.3.5 Example of analog/digital converter program
The example of an analog/digital converter program given here stores the A/D conversion values for pins AN0 to
AN7 in the memory area from 4000H to 403FH shown in Figure 8-8.
Figure 8-8. Memory Map (Store Example of A/D Conversion Result)
8
9
A
B
C
D
E
F
0
1
2
3
4
5
6
7
4000H
← AN0
4008H
← AN1
4010H
← AN2
4018H
← AN3
4020H
← AN4
4028H
← AN5
4030H
← AN6
4038H
← AN7
In this programming example the A/D converter is set to the scan mode. First, four A/D conversion operations
are performed on pins AN0 to AN3, and the AN0 to AN3 conversion results are stored in areas 4000H to 4003H,
4008H to 400BH, 4010H to 4013H, and 4018H to 401BH, respectively. Next, four A/D conversion operations are
performed on pins AN4 to AN7, and the AN4 to AN7 conversion results are stored in areas 4020H to 4023H, 4028H
to 402BH, 4030H to 4033H, and 4038H to 403BH, respectively. Then, conversion is performed again on pins AN0
to AN3, and the AN0 to AN3 conversion results are stored in areas 4004H to 4007H, 400CH to 400FH, 4014H to
4017H, and 401CH to 401FH, respectively. Finally, conversion is performed on pins AN4 to AN7, and the AN4 to
AN7 conversion results are stored in areas 4024H to 4027H, 402CH to 402FH, 4034H to 4037H, and 403CH to 403FH,
respectively. An example of a program which repeats the above operations show below.
First, the operation flow for initialization is shown in the following flowchart.
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CHAPTER 8
ANALOG/DIGITAL CONVERTER FUNCTIONS
ADIN
Set memory address
HL ← 4000H
<a>
Set counter
B ← 3
C ← 1
D ← 1
E ← 1
<b>
Set A/D channel
mode register
<c>
Reset INTFAD
<d>
Set interrupt
mask register
<e>
<a> The memory address for storing the A/D conversion results is set in the HL register pair. Here, the
setting is for storage of the conversion results in address 4000H onward.
<b> General registers B, C, D, and E are used as counters to enable the A/D conversion results to be stored
in the specified memory. The B register is used to check that A/D conversion has been performed four
times for pins AN0 to AN3 or pins AN4 to AN7. Therefore, 03H is set in the B register. The C, D, and
E register are stored in the respective memory areas, and 01H is set in each.
<c> The A/D channel mode register is set to specify the scan mode and AN0 to AN3 as the input pins.
Figure 8-9. A/D Channel Mode Register Settings
ANM
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
Scan mode
Pins AN0 to AN3
Oscillator frequency > 9 MHz
147
CHAPTER 8
ANALOG/DIGITAL CONVERTER FUNCTIONS
<d> The A/D channel mode register is cleared to 00H when a reset is performed, and A/D conversion is
performed on pins AN0 to AN3 in the scan mode. The conversion values are stored in register CR0
to CR3, and it is possible that the interrupt request flag (INTFAD) may be set (1). Therefore, the interrupt
request flag is reset (0) by a skip operation before setting the MKAD bit of the interrupt mask register
(MKH) to "0" and releasing masking.
<e> The MKAD bit of the interrupt mask register (MKH) is reset(0), releasing masking of INTAD internal
interrupts.
The A/D converter initialization routine is shown below.
;*****A/D CONVERTER INITIALIZATION*******
ADIN : LXI
H, 4000H
; Set data pointer
LXI
B, 0301H
; Set counter
LXI
D, 0101H
; Set counter
EXX
<b>
; Exchange register set
MVI
ANM, 00H
;
SKIT
FAD
; Reset INTFAD
NOP
ANI
<a>
MKH, 0FEH ; INTAD enable
<c>
<d>
<e>
In the INTAD interrupt service routine, the A/D conversion values in CR0 to CR3 are stored in the prescribed
memory locations. The operation flow is shown below.
148
CHAPTER 8
ADSE
Store
contents of
CR0 to CR3
in memory
ANALOG/DIGITAL CONVERTER FUNCTIONS
INTAD
<a>
<b>
Y
INTAD
X 4?
Breg
N
<c>
<d>
Y
4020H
end?
Set memory
address
HL ← HL + 1
N
Y
Creg
Set memory
address
HL ← 4020H
4004H
end?
N
<e>
Dreg
Set memory
address
HL ← 4004H
Set counter
C←0
Y
4024H
end?
N
<f>
Ereg
Set memory
address
HL ← 4024H
Set memory
address
HL ← 4000H
Set counters
C←0
D←0
Set counters
C←1
D←1
E←1
Set counter
B←3
Set A/D channel
mode register
invert ANI2 bit
RETI
<a> The contents of CR0 to CR3 which hold the A/D conversion values for pins AN0 to AN3 or pins AN4
to AN7 are stored in the prescribed memory locations.
<b> A check is made to see if an INTAD internal interrupt has been generated 4 times: If fewer than 4, the
HL register pair is incremented by 1 and control returns from the routine. If there have been 4 interrupts,
the program jumps to <c>. The B register is the counter used to check whether 4 interrupts have been
generated.
<c> As the A/D conversion values are stored in memory blocks starting at address 4000H (4000H to 4003H,
4008H to 400BH, 4010H to 4013H, and 4018H to 401BH), the start address (4020H) of the next block
is stored in the HL register pair, and 03H in the B register. The ANI2 bit of the A/D channel mode register
is inverted to change the input pin on which A/D conversion is to be performed, and a return is made
from the routine.
When A/D conversion values are stored in the memory blocks starting at 4020H (4020H to 4023H, 4028H
to 402BH, 4030H to 4033H, and 4038H to 403BH), the program jumps to <d>. The C register is the
counter used to check whether or not A/D conversion values have been stored in the memory blocks
starting at 4020H.
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CHAPTER 8
ANALOG/DIGITAL CONVERTER FUNCTIONS
<d> As the A/D conversion values are stored in memory blocks stating at address 4020H, the start address
(4004H) of the next block is stored in the HL register pair, 03H in the B register, and 00H in the C register.
The ANI2 bit of the A/D channel mode register is inverted to change the input pin on which A/D
conversion is to be performed, and a return is made from the routine.
When A/D conversion values are stored in the memory blocks starting at 4004H (4004H to 4007H,
400CH to 400FH, 4014H to 4017H, and 401CH to 401FH), the program jumps to <e>. The D register
is the counter used to check whether or not A/D conversion values have been stored in the memory
blocks starting at 4004H.
<e> As the A/D conversion values are stored in memory blocks starting at address 4004H, the start address
(4024H) of the next block is stored in the HL register pair, 03H in the B register, and 00H in the C register
and D register. The ANI2 bit of the A/D channel mode register is inverted to change the input pin on
which A/D conversion is to be performed, and a return is made from the routine.
When A/D conversion values are stored in the memory blocks starting at 4024H (4024H to 4027H,
402CH to 402FH, 4034H to 4037H, and 403CH to 403FH), the program jumps to <f>. The E register
is the counter used to check whether or not A/D conversion values have been stored in the memory
blocks starting at 4024H.
<f> The A/D conversion values are stored in memory blocks starting at address 4024H, and A/D conversion
values are stored in the entire area from 4000H to 403FH. Therefore, initialization is performed in order
to store A/D conversion values in the memory blocks starting at address 4000H once again.
The interrupt service routine is shown below. A JMP ADSE instruction must be stored in the INTAD interrupt
address. (0020H).
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CHAPTER 8
ANALOG/DIGITAL CONVERTER FUNCTIONS
;*****A/D CONVERTER SERVICE******
ADSE : EXA
; Save accumulator
EXX
; Save register
MOV
A, CR0
STAX
H
MOV
A, CR1
STAX
H+8H
MOV
A, CR2
STAX
H+10H
; Store A/D conversion data to memory
; Store A/D conversion data to memory
<a>
; Store A/D conversion data to memory
MOV
A, CR3
STAX
H+18H
; Store A/D conversion data to memory
DCR
B
; Decrement counter, skip if borrow
JR
ARIN
DCR
C
JR
ARST0
MOV
A, D
DCR
A
JR
ARST1
MOV
A, E
<c>
<d>
DCR
A
JR
ARST2
LXI
H, 4000H
; Set data pointer
LXI
D, 0101H
; Set counter
MVI
C, 01H
; Set counter
JR
RET1
ARIN : INX
JR
ARST0 : LXI
JR
ARST1 : LXI
H
H, 4004H
D, A
JR
RET0
H, 4024H
MOV
E, A
MVI
D, 00H
RET0 : MVI
C, 00H
RET1 : MVI
B, 03H
XRI
RET2 : EXA
; Increment HL
; Set data pointer
RET1
MOV
ARST2 : LXI
<e>
RET2
H, 4020H
ANM, 08H
<b>
<f>
<b>
<c>
; Set data pointer
<d>
; Set data pointer
<e>
; Invert ANI2 bit
; Recover accumulator
EXX
; Recover register
EI
; Enable interrupt
RETI
; Return
151
[MEMO]
152
CHAPTER 9 INTERRUPT CONTROL FUNCTIONS
There are 3 kinds of external interrupt request (NMI, INT1, INT2) and 8 kinds of internal interrupt requests (INTT0,
INTT1, INTE0, INTE1, INTEIN, INTAD, INTSR, INTST), plus a software interrupt instruction (SOFTI). The 11 kinds
of interrupt requests excluding the SOFTI instruction are divided into 6 groups, each of which is assigned a different
priority.
The interrupt addresses for the 6 interrupt request groups and the SOFTI instruction are fixed, and are shown
in Table 9-1.
Table 9-1. Priorities and Interrupt Addresses
Priority
Internal/
Interrupt Request
External
Interrupt Address
Decimal
Hexadecimal
1
External
NMI
Falling edge (non-maskable interrupt)
4
0004
2
Internal
INTT0
Match signal from TIMER0
8
0008
INTT1
Match signal from TIMER1
INT1
Rising edge
16
0010
INT2
Falling edge
INTE0
Match signal from timer/event counter
24
0018
INTE1
Match signal from timer/event counter
INTEIN
CI pin or TO fall signal
32
0020
INTAD
A/D converter interrupt
INTSR
Serial reception interrupt
40
0028
INTST
Serial transmission interrupt
96
0060
3
4
5
6
External
Internal
SOFTI instruction
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9.1 Interrupt Control Circuit Configuration
The interrupt control circuit consists of a request register, a mask register, a priority control, a test control, an
interrupt enable F/F (IE F/F) and a test flag register.
Figure 9-1. Interrupt Control Circuit Block Diagram
NMI
INTFNMI
INTT0
Skip control
Test
control
Request register
INTT1
INT1
INT2
INTE0
INTE1
INTEIN
T.F
INTFNMI
SOFTI
Mask
register
INTAD
IE F/F
INTST
Priority
control
EI
S
DI
R
Q
INTFNMI
OV
SB
Test flag
register
T.F
SOFTI
INT.
ADR
Internal bus
INTSR
ER
Interrupt
generation
AN7–4
(1) Request register
This register consists of 11 interrupt request flags which are set by the different interrupt requests. A flag
is reset when an interrupt request is acknowledged or a skip instruction (SKIT or SKNIT) is executed. RESET
input resets all flags. The interrupt request flags are not affected by the interrupt mask register.
•
INTFNMI
Set (1) by a falling edge input to the NMI pin. Unlike other interrupt request flags, this flag cannot be
tested by a skip instruction. However, the status of the NMI pin can be tested (see (6) Test flag register).
•
INTFT0
Set (1) by TIMER0 match signal.
•
INTFT1
Set (1) by TIMER1 match signal.
•
INTF1
Set (1) by a rising edge input to the INT1 pin.
•
INTF2
Set (1) by a falling edge input to the INT2 pin.
•
INTFE0
Set (1) when timer/event counter ECNT and ETM0 register contents match.
•
INTFE1
Set (1) when timer/event counter ECNT and ETM1 register contents match.
•
INTFEIN
Set (1) by a falling edge of the timer/event countr input (CI input) or timer output (TO).
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•
INTERRUPT CONTROL FUNCTIONS
INTFAD
Set (1) when A/D converter conversion values are transferred to the four registers CR0 to CR3.
•
INTFSR
Set (1) when the serial interface receive buffer becomes full.
•
INTFST
Set (1) when the serial interface transmit buffer becomes empty.
(2) Mask register
This is a 10-bit mask register which handles all interrupt requests except non-maskable interrupts (NMI). It
can be set (1) or reset (0) bit-wise by an instruction. An interrupt request is masked (disabled) or enabled
when the corresponding bit of the mask register is "1" or "0", respectively.
When RESET is input and in the hardware STOP mode all bits of the mask register are set (1), masking all
interrupt requests except non-maskable interrupts.
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Figure 9-2. Mask Register (MKL, MKH) Format
7
MKL
MKH
156
6
5
4
MKEIN MKE1 MKE0 MK2
3
2
1
MK1 MKT1 MKT0
7
6
5
4
3
–
–
–
–
–
2
1
0
–
0
INTT0 masking released
1
INTT0 masked
0
INTT1 masking released
1
INTT1 masked
0
INT1 masking released
1
INT1 masked
0
INT2 masking released
1
INT2 masked
0
INTE0 masking released
1
INTE0 masked
0
INTE1 masking released
1
INTE1 masked
0
INTEIN masking released
1
INTEIN masked
0
INTAD masking released
1
INTAD masked
0
INTSR masking released
1
INTSR masked
0
INTST masking released
1
INTST masked
0
MKST MKSR MKAD
CHAPTER 9
INTERRUPT CONTROL FUNCTIONS
(3) Priority control circuit
This circuit controls the 6 priority levels described earlier. If two or more interrupt request flags are set
simultaneously, the interrupt with the highest priority according to Table 9-1 is acknowledged, and the
remainder are held pending.
(4) Test control circuit
This circuit comes into operation when a skip instruction (SKIT or SKNIT) is executed to test interrupt request
flags (except INTFNMI) for each interrupt source, NMI pin states and test flags which do not generate an
interrupt request.
(5) Interrupt enable F/F (IE F/F)
This is a flip-flop which is set by the EI instruction and reset by the DI instruction. This flip-flop is reset when
an interrupt is acknowledged, and by RESET input, hardware and in STOP mode. Interrupts are enabled when
this flip-flop is set, and disabled when it is reset. Non-maskable interrupts can be acknowledged at any time
irrespective of the status of this flip-flop.
(6) Test flag register
This register consists of 8 test flags which do not generate interrupt requests.
•
NMI
Enables the NMI pin status to be tested. This flag is set to "1" when the NMI pin input level is "1", and
"0" when the level is "0".
•
OV
Set (1) when the timer/event counter ECNT overflows.
•
ER
Set (1) in the event of a parity error, framing error or overrun error in serial reception.
•
SB
Set (1) if VDD pin increases from a level lower than specified to a level higher than specified.
•
AN7 to AN4
Set (1) by a falling edge input to pins AN7 to AN4. Falling edge detection is performed by the same method
as in the case of the INT2 pin.
The above test flags can be tested by a skip instruction (SKIT or SKNIT). Test flags other than NMI are cleared
when tested. The NMI test flag is not changed by execution of an instruction and the pin status can be tested as
it is.
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9.2 External Interrupt Sampling
Pins NMI, INT1, INT2, and AN7 to AN4 have a noise elimination function to prevent errors due to noise signals.
(1) NMI input
This is the falling-edge-active non-maskable interrupt input. When the NMI signal is detected to be low for
at least a given time by the analog delay circuit, it is recognized as a normal signal and the INTFNMI interrupt
request flag is set.
At the end of the instruction INTFNMI is checked and if set, the program jumps to the interrupt address for
non-maskable interrupts regardless of the EI/DI state. When an interrupt request is acknowledged, INTFNMI
is automatically reset.
(2) INT1 input
This is the rising-edge-active maskable interrupt input. When the INT1 signal changes from low to high, and
the high level is detected in 3 or more successive φ12 cycle sampling pulses (12 states: 2.4 µs at 15 MHz),
the input is recognized as a normal signal and the INTF1 interrupt request flag is set.
When masking is released in the EI state, a check is made that the INTF1 is set at the end of the instruction,
and if there is no other interrupt request of higher priority, the INT1 interrupt is acknowledged and the program
jumps to the interrupt address. Interrupt request flag resetting is described in 9.4 Maskable Interrupt
Operation.
A new INT1 interrupt is detected when the INT1 signal is high for at least 12 states after first returning to
the low level.
(3) INT2 input
This is the falling-edge-active maskable interrupt input. Except for having the opposite active state, its
functions are the same as those of the INT1 input.
(4) AN7 to AN4 inputs
A falling edge is detected by the same method as for the INT2 input, and the test flag is set (AN7 to AN4
of the test flag register). These flags can be tested by an instruction (SKIT or SKNIT), and are automatically
reset when tested. In setting a testable flag again, the criterion for detection is a low-level input signal for
a duration of at least 12 states after first returning to the high level.
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Figure 9-3. Interrupt Sampling
φ12
Sampling
pulses
INT2,
AN7 – AN4
INT1
Valid
Noise
Valid
INTF1, 2
AN7-AN4
As can be seen from the above diagram, INT1, INT2 and AN7 to AN4 are determined to be correct interrupt signals
when the active level is detected in 3 or more φ12 (0.8 µs at 15 MHz operation) cycle sampling pulses. Therefore,
noise signals of 8 states (1.6 µs at 15 MHz operation) or shorter duration are eliminated, and the interrupt request
flag is properly set by a high-level or low-level input of at least 12 states (2.4 µs at 15 MHz operation).
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INTERRUPT CONTROL FUNCTIONS
9.3 Non-Maskable Interrupt Operation
When the INTFNMI interrupt request flag is set by a falling edge input to the NMI pin, a non-maskable interrupt
is acknowledged by means of the following procedure irrespective of the EI/DI state (see Figure 9-4).
(i)
A check is made to see if INTFNMI is set at the end of each instruction. If INTFNMI is set, a non-maskable
interrupt is acknowledged at INTFNMI is reset.
(ii) When the non-maskable interrupt is acknowledged, the IE F/F is reset and all interrupts except for nonmaskable interrupts and the SOFTI instruction are placed in the disabled state (DI state).
(iii) PSW, PC high byte and PC low byte are saved into the stack memory in that order.
(iv) The program jumps to the interrupt address (0004H).
These interrupt operations are automatically carried out in 16 states.
Caution Operations when a non-maskable interrupt is generated directly after a maskable interrupt
(1)
The PC value at the time of the interrupt is saved to the stack.
(2)
The vector address of the maskable interrupt is stored in the PC, and the corresponding
(3)
Non-maskable interrupt servicing is executed before execution of the maskable interrupt
(4)
The non-maskable interrupt routine is executed.
interrupt request flag is reset.
routine.
In this case, the return destination from the non-maskable interrupt routine is the maskable
interrupt routine.
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INTERRUPT CONTROL FUNCTIONS
Figure 9-4. Interrupt Operation Procedure
End of
instruction
Y
NM I?
N
DI state?
Y
N
All
masked?
Y
N
Check nonmasked
INTFx
Reset INTFNMI
2 or more
Other
interrupt
Number
of flags set
0
1
Next
instruction
Check
priority
Pending
Highest-priority
interrupt
Same level
interrupts both nonmaskable?
Y
N
Reset INTFx
Reset IE F/F
Save PSW &
PC to stack
memory
PC ← interrupt address
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When execution of the interrupt service routine ends, processing is performed to return to the address at which
the interrupt was acknowledged. First, registers, flags, etc., other than the PSW which have been save are restored,
and if necessary the IE F/F is set by the EI instruction. Next, the RETI instruction is used to restore the previously
saved return address and PSW in the order: Lower PC byte, upper PC byte, PSW.
Since interrupt servicing is performed for non-maskable interrupts irrespective of the status of the IE F/F, they
are useful for program processing in the event of an emergency such as a power failure.
The configuration of the NMI pin is shown in Figure 9-5. Although INTFNMI cannot be tested by a skip instruction,
the NMI pin status can be tested by a skip instruction (SKIT NMI or SKNIT NMI). Thus, in the non-maskable interrupt
service routine, relatively wide noise can be removed by testing the NMI pin status several times using a skip
instruction. The NMI pin status is not changed when tested by a skip instruction.
Caution The IE F/F is reset unconditionally when a non-maskable interrupt is generated, and the contents
of the IE F/F prior to the non-maskable interrupt are not saved. Therefore, when returning to
the main routine the original status of the IE F/F should be determined by means of the stack
address when the non-maskable interrupt was generated.
Figure 9-5. Internal Configuration of NMI Pin
NMI
D
Q
Falling
edge
detection
NMI
S
Q
R
Non-maskable
interrupt
acknowledgment
Test control
µ PD78C18
162
Non-maskable
interrupt
request
CHAPTER 9
INTERRUPT CONTROL FUNCTIONS
9.4 Maskable Interrupt Operation
Interrupt requests except non-maskable interrupts and the SOFTI instruction are maskable interrupts which can
be enabled/disabled (IE F/F set/reset) by the EI/DI instructions and can be masked individually by means of the mask
register.
When an external maskable interrupt is recognized as a normal interrupt signal by an active level input for more
than the specified time, an interrupt request flag is set. If an internal interrupt request is generated, an interrupt
request flag is immediately set. Once the interrupt request flag is set, both the external and internal interrupts are
serviced using the following procedure (see Figure 9-3 Interrupt Sampling).
(i)
In the EI state (IE F/F=1), a check is made to see if the interrupt request flag has been set at the end
checked at end of each instruction. If the flag has been set, the interrupt cycle starts. However, interrupt
requests masked by the mask register are not checked.
(ii) If two or more interrupt request flags have been set simultaneously, their priorities are checked. The
interrupt with the highest priority is acknowledged and the others are held pending.
(iii) When an interrupt request is acknowledged, the interrupt request flag is automatically reset. If two types
of interrupt requests with the same priority have both been unmasked by the mask register, the interrupt
request flag is not reset. This is because the two types are identified by software at a later stage.
(iv) When an interrupt request is acknowledged, the IE F/F is reset, and all interrupts except non-maskable
interrupts and the SOFTI instruction are placed in the disabled state (DI state).
(v) The PSW, upper PC byte and lower PC byte are saved to the stack memory in that order.
(vi) The program jumps to the interrupt address.
These interrupt operations are automatically carried out in 16 states.
The pending interrupt requests are acknowledged if there are no other interrupt requests of higher priority when
interrupts are enabled by execution of the EI instruction.
With maskable interrupts there are two types of interrupt requests with the same priority and same interrupt
address. Unmasking both types, unmasking one type, or masking both kinds can be selected by setting the mask
register.
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INTERRUPT CONTROL FUNCTIONS
(1) When both types are unmasked
The corresponding bits of the mask register for two types of interrupt requests are both set to "0". In this
case, the interrupt request is the logical sum of the two interrupt request flags.
If an interrupt request is acknowledged in accordance with the interrupt operation as a result of setting one
or both interrupt request flags having the same priority and the program jumps to the interrupt address, the
interrupt request flag is not reset. Therefore, the interrupt request is identified by executing a skip instruction
which tests the interrupt request flag at the beginning of the interrupt service routine, and the interrupt request
flag is reset.
The priority of interrupt requests with the same priority can be freely decided by the user by determining which
of the two is first subject to execution of the skip instruction.
The interrupt servicing sequence when both INT1 and INT2 are unmasked is shown in Figure 9-6.
Figure 9-6. Interrupt Servicing Sequence (Masking released for both INT1 and INT2)
(0010H)
Save registers
EI
N
INTF1=1
?
Y
INT1 interrupt
service program
INT1 or INT2
INTF2=1
?
Y
N
INT2 interrupt
service program
Restore registers
EI
RETI
Remark
In this example masking is released for both INT1 and INT2 interrupt requests which have the same
priority.
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INTERRUPT CONTROL FUNCTIONS
(2) When one type is unmasked
For two types of interrupt requests having the same priority, the corresponding bit of the mask register for
the interrupt request to be unmasked is set to "0" and the other bit is set to "1". In this case, if an interrupt
request is generated by setting the unmasked interrupt request flag and that interrupt request is acknowledged
in accordance with the interrupt operation, the interrupt request flag is automatically reset.
When the masked interrupt request flag is set, that interrupt request is held pending. When the pending
interrupt request is unmasked, it is acknowledged if there are no other interrupt requests of higher priority
in the interrupt enable state. Whether or not the interrupt request flag for the acknowledged interrupt is
automatically reset depends on the setting of the mask register of the same priority. If the other interrupt
request is masked when masking is released the interrupt request flag is automatically reset, but if the other
interrupt request remains unmasked when masking is released, the interrupt request flag is not reset even
though the interrupt request is acknowledged (see 9.4 (1) When both types are unmasked).
Figure 9-7. Interrupt Servicing Sequence (Masking released for either INT1 or INT2)
EI
Save registers
INT
Interrupt service
program
Restore registers
EI
RETI
Remark
In this example masking is released by the mask register for one of the interrupt requests which have
the same priority.
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INTERRUPT CONTROL FUNCTIONS
(3) When both types are masked
The corresponding bits of the mask register for two types of interrupt request are both set to "1". In this case,
the interrupt requests are held pending are not acknowledged when the interrupt request flag is set. When
the pending interrupt requests are unmasked, they are acknowledged if there are no other interrupt requests
of higher priority in the interrupt enabled state.
When execution of the interrupt service routine ends, processing is performed to return to the address at which
the interrupt was acknowledged. First, registers, flags, etc., other than the PSW which have been saved are restored,
and the IE F/F is set by the EI instruction. Next, an RETI instruction is executed to restore the previously saved return
address and PSW in the order: lower PC byte, upper PC byte, PSW.
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9.5 Interrupt Operation by SOFTI Instruction
When the SOFTI instruction is executed, the program jumps unconditionally to the interrupt address (0060H).
The SOFTI instruction interrupt is not affected by the IE F/F, and the IE F/F is not affected when this instruction
is executed.
The servicing procedure for an interrupt generated by the SOFTI instruction is as follows:
(i)
The PSW, upper PC byte and lower PC byte are saved to the stack memory in that order.
(ii) The program jumps to the interrupt address (0060H).
When execution of the interrupt service routine ends, processing is performed to return to the address at which
the interrupt was acknowledged. First, registers, flags, etc., other than the PSW which have been saved are restored.
Next, a RETI instruction is executed to restore the previously saved return address and PSW in the order: lower
PC byte, upper PC byte, PSW.
Caution If the skip condition is satisfied by the instruction (arithmetic or logical operation, increment/
decrement, shift, skip or RETS instruction) immediately before the SOFTI instruction, the SOFTI
instruction is executed and not skipped. When SOFTI instruction is executed, the SK flag of the
PSW is saved as set (1) to the stack area. Thus, when the return is made from the SOFTI service
routine, the PSW SK flag remains set and the instruction following the SOFTI instruction is
skipped.
Note that the 87AD series SOFTI instruction differs from that of the µCOM-87 in that the address
contents saved to the stack memory are the start address of the next instruction.
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9.6 Interrupt Wait Time
The time required from acknowledgement by the CPU of an asynchronously generated external interrupt until
execution of the first instruction of the relevant interrupt service routine begins (the interrupt wait time) is the sum
of time components I, II and III shown in Table 9-2.
This interrupt wait time varies depending on the kind of instruction being executed when the interrupt occurs and
the instruction timing at which the interrupt occurs.
Table 9-2 shows maximum interrupt wait times.
The 14 states of component I (10 µs max. in the case of NMI) indicate the time required until the interrupt request
signal becomes active and is recognized as a normal signal, and INTFx is set (1). Therefore, this time is only required
in the case of NMI, INT1 and INT2 interrupts.
The 59 states of component II indicate the instruction execution time for the longest instruction. This time depends
on the performance of the INTFx check at the end of each instruction (METE). Thus the required time for component
II varies depending on the instruction being executed at that time, from a minimum of 4 states to a maximum of
59 states.
The 16 states of component III represent the time required to save the contents of the PSW and PC to the stack
memory.
Table 9-2. Maximum Interrupt Wait Time
Wait Time Components
INT1, INT2
NMI
Others
I
Time required for noise elimination
14 states
10 µs MAX.
0 states
II
Time required for instruction execution (divide instruction)
59 states
59 states
59 states
III
Time required for automatic save processing
16 states
16 states
16 states
89 states
75 states + 10 µs
75 states
Total time
168
(22.25 µs/12 MHz) (28.75 µs/12 MHz) (18.75 µs/12 MHz)
CHAPTER 9
INTERRUPT CONTROL FUNCTIONS
9.7 Multiple Interrupts
When the EI instruction is executed all external and internal interrupt requests are enabled even when an interrupt
service routine is being executed. Therefore, when the EI instruction is executed during execution of an interrupt
service routine, acknowledgement is enabled even for that interrupt request itself or interrupt requests of lower
priority. In this case too, if multiple interrupt requests are generated simultaneously, the highest-priority request
is acknowledged and the lower-priority requests are held pending. The pending interrupt requests are acknowledged
when the EI state is subsequently entered, if no other interrupt requests of higher priority have been generated.
Since there are practically no restrictions on the stack area used when an interrupt is generated as long as the
memory size is sufficient, multiple interrupt levels can also be used without restriction (see Figure 9-8).
Figure 9-8. 3-Level Multiple Interrupts
(0010H)
(0008H)
EI
EI
INT1
(0018H)
EI
INTT0
EI
ORI MKH, 02H
INTE0
INTSR
Not acknowledged
ANI MKH, 0FDH
(0028H)
RETI
RETI
EI RETI
EI
RETI
Remark
If masking is released by the mask register for two interrupt sources of the same priority, which of the
two interrupt requests is concerned must be determined before executing the EI instruction at the start
of the interrupt service routine.
169
[MEMO]
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CHAPTER 10 CONTROL FUNCTIONS
10.1 Standby Functions
Three standby modes are available for the µPD78C18 to save power consumption in the program standby state:
The HALT mode, software STOP mode, and hardware STOP mode.
10.1.1 HALT mode
When the HLT instruction is executed, the HALT mode is set unless the interrupt request flag of the unmasked
interrupt is set. In the HALT mode the CPU clock stops and program execution also stops. However, the contents
of all registers and on-chip RAM just before the stoppage are retained. In the HALT mode, the timer, timer/event
counter, serial interface, A/D converter and interrupt control circuit are operational. Table 10-1 shows the status of
the µPD78C18 output pins in the HALT mode.
Table 10-1. Output Pin Statuses
Output Pin
Single ChipNote 1
External Expansion
PA7 to PA0
Data retained
Data retained
PB7 to PB0
Data retained
Data retained
PC7 to PC0
Data retained
Data retained
PD7 to PD0
Data retained
High-impedance
PF7 to PF0
Data retained
Next address retainedNote 2
Data retainedNote 3
WR, RD
High-level
High-level
ALE
High-level
High-level
Notes 1.
µPD78C18/78C14/78C14A/78C12A/78C11A/78CP18/78CP14
2.
Address output pin
3.
Port data output pin
Cautions 1. Because an interrupt request flag is used to release the HALT mode, HLT instruction
execution does not set the HALT mode if even a single interrupt request flag for an unmasked
interrupt is set. Thus, when setting the HALT mode when there is a possibility that an
interrupt request flag may have been set (when there is a pending interrupt), one of the
following procedures should be followed: First process the pending interrupt; or, reset the
interrupt request flag by executing a skip instruction; or, mask all interrupts except those
used to release the HALT mode.
2. This function is valid when pins PC7 to PC0 are in the control signal input/output mode.
Therefore, TO output and serial transmission/reception is enabled in the HALT mode.
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10.1.2 HALT mode release
(1) Release by RESET signal
When the RESET signal changes from the high to low level in the HALT mode, the HALT mode is released
and the reset state is set. When the RESET signal returns to the high level, the CPU starts program execution
at address 0.
When the RESET signal is input, the RAM contents are retained but the contents of other registers are
indeterminate.
Figure 10-1. HALT Mode Release Timing (RESET Signal Input)
Execution of address 0
instruction
CPU
HLT
CSC
RESET
(2) Release by interrupt request flag
The HALT mode is released if at least one interrupt request flag is set by the generation of a non-maskable
interrupt (NMI) or one of ten unmasked maskable interrupts (INTT0, INTT1, INT1, INT2, INTE0, INTE1, INTEIN,
INTAD, INTST and INTSR).
When the HALT mode is released by a non-maskable interrupt, the instruction following the HLT instruction
is not executed and the program jumps to the interrupt address (0004H) irrespective of the interrupt enabled/
disabled (EI/DI) state.
When the HALT mode is released by a maskable interrupt, operation after release differs depending on
whether the EI or DI state is set.
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CHAPTER 10
(i)
CONTROL FUNCTIONS
EI state
The instruction following the HLT instruction is not executed and the program jumps to the corresponding
interrupt address.
Figure 10-2. HALT Mode Release Timing (In EI State)
CPU
operation
Interrupt
execution
HLT
Interrupt
routine
OSC
INTFx
(ii) DI state
Execution restarts with the instruction following the HLT instruction (without jumping to the interrupt
address). Since the interrupt request flag used for release remains set, it should be reset by a skip
instruction when required.
Figure 10-3. HALT Mode Release Timing (In DI State)
CPU
operation
Execution of next
instruction
HLT
OSC
INTFx
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10.1.3 Software STOP mode
When the STOP instruction is executed, the software STOP mode is set unless the interrupt request flag for an
unmasked external interrupt is set. In the software STOP mode, all clocks stop. When this mode is set, program
execution stops and the contents of all registers, on-chip RAM and flags except FT0 and FT1 just before stoppage
are retained (the timer upcounter is cleared to 00H). Only the NMI and RESET signals used to release the software
STOP mode are valid, and all other functions stop.
The statuses of the µPD78C18 output pins in the software STOP mode are the same as for the HALT mode, as
shown in Table 10-2.
Table 10-2. Output Pin Statuses
Output Pin
Single ChipNote 1
External Expansion
PA7 to PA0
Data retained
Data retained
PB7 to PB0
Data retained
Data retained
PC7 to PC0
Data retained
Data retained
PD7 to PD0
Data retained
High-impedance
PF7 to PF0
Data retained
Next address retainedNote 2
Data retainedNote 3
WR, RD
High-level
High-level
ALE
High-level
High-level
Notes 1.
µPD78C18/78C14/78C14A/78C12A/78C11A/78CP18/78CP14
2.
Address output pin
3.
Port data output pin
Cautions 1. Internal interrupts should be masked before executing the STOP instruction to prevent
errors due to an internal interrupt with the oscillation stabilization time upon release of the
software STOP mode.
2. The TIMER1 coincidence signal is used as the signal to start CPU operation to secure an
oscillation stabilization period after the software STOP mode has been released by setting
the non-maskable interrupt request flag. Thus, it is necessary to set a count value in timer
REG which takes account of the oscillation stabilization time, and to set the timer mode
register to the timer operating state, before executing the STOP instruction.
3. Crystal oscillation or ceramic oscillation should be used when using the software STOP
mode. The software STOP mode must not be used when an external clock is input.
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10.1.4 Software STOP mode release
(1) Release by RESET signal
When the RESET signal changes from the high to low level in the software STOP mode, the software STOP
mode is released and clock oscillation starts as soon as the reset state is set. When the RESET signal is driven
high after oscillation has stabilized, the CPU starts program execution at address 0.
When the RESET signal changes from the high to low level, clock oscillation starts but it takes time for
oscillation to stabilize. The RESET signal low-level width must therefore be longer than the oscillation
stabilization time.
When the RESET signal is input, the RAM contents are retained but the contents of other registers are
indeterminate.
Figure 10-4. Software STOP Mode Release Timing (RESET Signal Input)
CPU
operation
Execution of address 0
instruction
STOP
OSC
RESET
If the software STOP mode is released by the RESET signal, program execution starts at address 0 as in the
case of a normal power-on reset. The SB (Standby) flag can be used to identify the program execution mode.
The SB flag is set (1) when the VDD pin rises from the specified low level or below to the specified high level
or above, and is reset (0) by executing a skip instruction. Thus, testing the SB flag using a skip instruction
in the program executed after RESET input makes it possible to differentiate between a power-on start and
a start due to release of the software STOP mode (see Figure 10-5). A set (1) SB flag indicates a poweron start, and a reset (0) SB flag indicates a start due to release of the software STOP mode.
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CONTROL FUNCTIONS
Figure 10-5. SB Flag Operation
VDD
RESET
SB flag
CPU
operation
Note 1
Note 2
Note 3
Note 1
Note 2
Software STOP
mode
Notes
1. Execution of address 0 instruction
2. Execution of SKIT SB or SKNIT SB instruction
3. Execution of STOP instruction
(2) Release by NMI pin input
When the non-maskable interrupt request flag is set (i.e. when the NMI pin input changes from high to low)
in the software STOP mode, the software STOP mode is released and simultaneously clock oscillation starts.
When clock oscillation starts, the timer upcounter starts counting up from 00H in accordance with the setting
before execution of the STOP instruction. CPU operation is started by a match signal (wait time taking account
of the oscillation stabilization time) from the TIMER1 upcounter. In this case, the upcounter match signal
does not set the interrupt request flag. The timer mode register of the timer after generation of the match
signal is set to FFH and timer operation is stopped.
After the elapse of the oscillation stabilization time, the program jumps to the interrupt address (0004H)
irrespective of the interrupt enabled/disabled (EI/DI) state and without executing the instruction following the
STOP instruction.
Figure 10-6. Software STOP Mode Release Timing (NMI Signal Input)
CPU
operation
Interrupt execution
Interrupt
routine
STOP
OSC
NMI
INTFNMI
Wait (programmable)
TIMER1
match
signal
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CONTROL FUNCTIONS
10.1.5 Hardware STOP mode
When the STOP signal changes from the high to low level, the hardware STOP mode is set. In this mode all clocks
stop. When the hardware STOP mode is set, program execution stops and the on-chip RAM contents just before
stoppage are retained, and the STOP signal used to release the hardware STOP mode is valid. All other functions
stop and the reset state is set. In the hardware STOP mode, the µPD78C18 output pins become high-impedance.
However, the port output latch values are retained.
Cautions
1. Crystal oscillation or ceramic oscillation should be used when using the hardware STOP
mode. The hardware STOP mode must not be used when an external clock is input.
2. The STOP mode is entered at a machine cycle boundary. Thus memory contents are not
corrupted, but the STOP mode may be entered midway through execution of an instruction.
Therefore, with instructions which perform a 16-bit data transfer the STOP mode may be
entered after only 8 bits have been transferred, with the transfer of the remaining 8 bits
incomplete (16-bit data transfer instructions and call instructions).
3. If the STOP signal is input (high low level) during reset input (RESET = low level), a transition
is made from the reset state to the STOP mode.
4. The STOP pin must be driven high after powering-on. The reset will not function correctly
if the STOP pin is left low. The STOP pin can be driven low after oscillator operation has
stabilized.
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10.1.6 Hardware STOP mode release
When the STOP signal changes from the low to high level in the hardware STOP mode, the hardware STOP mode
is released and simultaneously clock oscillation starts. After the elapse of the wait time (approximately 65 ms at
12 MHz) which takes account of the oscillation stabilization time, the CPU starts program execution at address 0
(see Figure 10-7).
Figure 10-7. Hardware STOP Mode Release Timing (STOP Signal Input)
STOP
Instruction
execution
Wait (approx. 65 ms/12 MHz)
Execution of
address 0
instruction
CPU
operation
OSC
The hardware STOP mode is not released by a high-to-low transition of the RESET signal.
When the STOP signal changes from low to high while the RESET signal is low, the hardware STOP mode is
released and clock oscillation starts. If the RESET signal returns from the low to high level, the CPU starts program
execution at address 0 without waiting for the elapse of the oscillation stabilization time (see Figure 10-8).
If the RESET signal changes from the high to low level just after the hardware STOP mode has been released
(after the STOP signal has changed from the low to high level), program execution starts when the RESET signal
chnages from the low to high level (see Figure 10-9).
The oscillation stabilization time should therefore be taken into account when returning the RESET signal to the
high level.
After RESET signal input RAM contents are retained, but the contents of other registers are undefined.
Figure 10-8. Hardware STOP Mode Release Timing (RESET Signal Input)
STOP
Instruction
execution
Execution of address 0
instruction
CPU
operation
Wait
RESET
OSC
178
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CONTROL FUNCTIONS
Figure 10-9. Hardware STOP Mode Release Timing (STOP Signal Rising to RESET Signal Input)
STOP
Instruction
execution
Execution of address 0
instruction
CPU
operation
RESET
OSC
In the case of a hardware STOP mode release, as with a release of the software STOP mode by means of the
RESET signal, it is possible to differentiate between a power-on start and a start due to release of the hardware STOP
mode by testing the SB flag using a skip instruction.
10.1.7 Low supply voltage data retention mode
The low supply voltage data retention mode can be set by decreasing the VDD supply voltage after setting the
software/hardware STOP mode. RAM contents can be retained with lower power dissipation than in the software/
hardware STOP mode.
When returning from the software/hardware STOP mode by means of a reset, the SB flag is used to determine
whether the reset is a power-on reset. The SB flag is set (1) only when the supply voltage (VDD) changes from a
given voltage or below to a given voltage or above. This flag can be tested by the SKIT SB or SKNIT SB instruction,
and is automatically reset (0) when either of these instructions is executed.
Figure 10-10. Relation between VDD and SB Flag
VDD
SB flag
SKIT SB
SKNIT SB
STOP mode entered
Instruction
execution
Caution The software/hardware STOP mode should not be released while in the low supply voltage data
retention mode. VDD must be raised to the normal operating voltage before the release is
performed.
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CONTROL FUNCTIONS
10.2 Reset Functions
When a low level signal is input to the RESET pin, a system reset is effected and initialization is performed as
shown below.
Table 10-3. Hardware States after Reset (1/2)
Hardware
Internal data
Power-on reset
memory
Reset input
During CPU
during normal
write operation
State after Reset
Previous contents retained
Write address data
Undefined
Data in other addresses
Previous contents retained
operation
During non-write CPU operation
Extended accumulator (EA, EA')
Undefined
Accumulators (A, A')
General-purpose register (B, C, D, E, H, L, B', C', D', E', H', L')
Working register/vector register (V, V')
Program counter (PC)
0000H
Stack pointer (SP)
Undefined
Ports
Mode registers (MA, MB, MC, MF)
FFH
Mode control register (MMC)
00H
MM registers (MM0, 1, 2)
Port output latches
Interrupts
Undefined
Interrupt enable F/F
0
Request flags
Mask register
FFH
Test flags (except SB flag)
0
Standby flag (SB)
Power-on reset
1
In standby mode
Previous contents retained
Reset input during normal operation
Contents before RESET input
retained
Timer
Timer/event counter
Timer mode register (TMM)
FFH
Timer F/F
0
Timer registers (TM0, TM1)
Undefined
Timer/event counter mode register (ETMM)
00H
Timer/event counter output mode register (EOM)
Timer/event counter registers (ETM0, ETM1)
Undefined
Timer/event counter capture register (ECPT)
Timer/event counter (ECNT)
Serial interface
180
Serial mode high register (SMH)
00H
Serial mode low register (SML)
48H
CHAPTER 10
CONTROL FUNCTIONS
Table 10-3. Hardware States after Reset (2/2)
Hardware
State after Reset
A/D channel mode register (ANM)
00H
MM register RAE bit (MM3)
Undefined
Zero-cross mode register (ZC)
1
Table 10-4. Pin States after Reset
Pin
State after Reset
WR
High-impedance
RD
ALE
All ports (PA, PB, PC, PD, PF)
When the RESET input changes from low to high, program execution starts at address 0000H; the contents of
the various registers should be initialized or re-initialized as required in the program.
Caution With an external clock input, if VDD is within the operating voltage range all the pins are highimpedance after RESET signal input. Then a system reset is effected after X1 input. However,
this does not apply when the clock is not input at all to X1 after powering-on.
X1 input
X1
RESET input
RESET
System reset
Ports become high-impedance.
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CONTROL FUNCTIONS
10.3 Clock Generation Circuit
The µPD78C18 incorporates a clock generation circuit, allowing the necessary clock to be generated simply by
connecting a crystal or a ceramic resonator and capacitors. It is also possible to input an externally generated clock.
Figure 10-11 shows a circuit with a resonator connected, and Figure 10-12 shows an example of a circuit when an
external clock is input.
Figure 10-11. Oscillator Connection Circuit
Figure 10-12.
Example of External Clock Input
Circuit
µ PD78C18
X1
µ PD78C18
X2
C1
X1
C2
X2
HCMOS
inverter
Caution When using the system clock oscillator, the shaded area in Figure 10-11 should be wired in order
to avoid effects of wiring capacitor etc., as shown below.
• Minimize the length of wiring.
• Do not cross other signal lines, or position wiring close to a variable high current.
• The connecting point of the oscillator capacitor should always be the same potential as VSS.
Do not connect it to the gland pattern where there is a high current.
• Do not pick up the signal from the oscillator.
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CONTROL FUNCTIONS
Figure 10-13. Examples of Poor Resonator Connection Circuit
(a) Long Connection Circuit Wiring
(b) Crossed Signal Lines
µ PD78C18
X1
X2
µ PD78C18
VSS
X1
(c) Signal Line Close to Varying High Current
X2
PAn
VSS
(d) Current Flows an Oscillator Ground Line
(Potentials at A, B, and C fluctuate)
VDD
µ PD78C18
µ PD78C18
X1
X2
VSS
PAn
X1
X2
VSS
High
current
A
B
C
(e) Signal is Picked Up
µ PD78C18
X1
X2
VSS
183
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CONTROL FUNCTIONS
The wiring should also be kept as short as possible when an external clock is input, to prevent the effects of
extraneous electromagnetic wave radiation or external noise.
When the hardware/software STOP mode is entered, the X1 and X2 pin levels are fixed. Therefore, the hardware/
software STOP mode should not be used when an external clock is used. When the hardware/software STOP mode
is used, a crystal or ceramic resonator should be used.
When the device is powered on, and when returning from the hardware/software STOP mode, sufficient time
must be allowed for the oscillation to stabilize. The time required for oscillation stabilization is several ms when a
crystal is used, and several hundred µs when a ceramic resonator is used.
An adequate oscillation stabilization period should be secured by the following means:
<1> RESET input when powering-on (reset period).
<2> RESET input (reset period) or automatically used timer when returning from the hardware STOP mode.
<3> RESET input or preset timer when returning from the software STOP mode.
Using a crystal resonator, C1 = C2 = 10 pF should be kept. The values of C1 and C2 as recommended resonator
when a ceramic resonator is used are shown in Table 10-5.
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CHAPTER 10
CONTROL FUNCTIONS
Table 10-5. Recommended Ceramic Resonator (1/2)
Product Name
Manufacturer
Part Name
Recommended
C1 [pF]
C2 [pF]
CSA15.00MX001
15
15
78C11A,
CSA12.0MT
30
30
78C12A
CST12.0MT
Build in
Built in
CST12.0MTW
Built in
Built in
CSA7.37MT
30
30
CST7.37MT
Built in
Built in
CST7.37MTW
Built in
Built in
FCR15.0MC
Built in
Built in
FCR10.0MC
Built in
Built in
FCR8.0MC
Built in
Built in
CSA15.0MX3
22
22
CSA12.0MT
30
30
CST12.0MT
Built in
Built in
CST12.0MTW
Built in
Built in
CSA10.0MT
30
30
CST10.0MT
Built in
Built in
CST10.0MTW
Built in
Built in
CSA6.00MG
30
30
CST6.00MG
Built in
Built in
FCR15.0MC
Built in
Built in
FCR12.0MC
Built in
Built in
FCR10.0MC
Built in
Built in
FCR8.0MC
Built in
Built in
CSA15.0MX3
22
22
CSA12.0MT
30
30
CST12.0MT
Built in
Built in
CST12.0MTW
Built in
Built in
CSA10.0MT
30
30
CST10.0MT
Built in
Built in
CST10.0MTW
Built in
Built in
CSA6.00MG
30
30
CST6.00MG
Built in
Built in
FCR12.0MC
Built in
Built in
µPD78C10A,
Murata Mfg. Co., Ltd.
TDK
µPD78C14
Murata Mfg. Co., Ltd.
TDK
µPD78C14A
Murata Mfg. Co., Ltd.
TDK
185
CHAPTER 10
CONTROL FUNCTIONS
Table 10-5. Recommended Ceramic Resonator (2/2)
Recommended
Product Name
µPD78CG14
µPD78CP14
Manufacturer
Murata Mfg. Co., Ltd.
Murata Mfg. Co., Ltd.
Part Name
C1 [pF]
C2 [pF]
CSA15.0MX3
22
22
CSA12.0MT
30
30
CST12.0MT
Built in
Built in
CSA12.0MT
30
30
Built in
Built in
30
30
Built in
Built in
30
30
Built in
Built in
22
22
Built in
Built in
30
30
Built in
Built in
30
30
CST8.00MTW
Built in
Built in
FCR15.0MC
Built in
Built in
FCR10.0MC
Built in
Built in
FCR8.0MC
Built in
Built in
CST12.0MTW
CSA10.0MT
CST10.0MTW
CSA8.00MT
CST8.00MTW
µPD78C17,
Murata Mfg. Co., Ltd.
78C18
CSA15.00MX001
CST15.00MXW001
CSA10.0MT
CST10.0MTW
CSA8.00MT
TDK
Remark
Use of crystal and ceramic resonator
Generally speaking, the oscillation frequency of a crystal is extremely stable, and it is therefore ideal
for high-precision time management (for example, in clocks and watches, measuring instruments, etc.).
The oscillation frequency stability of a ceramic resonator is not as high as that of a crystal, but it offers
three advantages: a fast oscillation start-up time, small size, and low cost. It is therefore suitable for
general applications in which high-precision time management is not required. In addition, products
with built-in capacitors, etc., are available, offering the advantage of fewer parts and reduced mounting
area.
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CHAPTER 11 EXTERNAL DEVICE ACCESSES AND TIMINGS
11.1 µPD78C18/78C14/78C14A/78C12A/78C11A External Device Accesses
For the µPD78C18/78C14/78C14A/78C12A/78C11A, the areas shown below can be used for external device
expansion (data memory, program memory or peripheral devices).
•
•
•
•
µPD78C18
: Addresses 8000H to FBFFH (31K bytes)
µPD78C14, 78C14A : Addresses 4000H to FEFFH (48K bytes)
µPD78C12A
: Addresses 2000H to FEFFH (56K bytes)
µPD78C11A
: Addresses 1000H to FEFFH (60K bytes)
The memory mapping register (MM) is used for external device expansion. Pins PD7 to PD0 are used as a
multiplexed address/data bus (AD7 to AD0), and pins PF7 to PF0 are used as an address bus (AB15 to AB8). With
pins PF7 to PF0, the number of bits functioning as the address bus can be varied according to the size of the external
expansion memory, and memory can be expanded in steps from 256 bytes up to 31K/48K/56K/60K bytes (depending
on the product). Pins which are not used for the address bus can be used as general-purpose input/output port pins
(see Table 11-1).
Table 11-1. PF7 to PF0 Address Bus Selection
PF7
PF6
PF5
PF4
PF3
PF2
PF1
PF0
External Address Space
Port
Port
Port
Port
Port
Port
Port
Port
Up to 256 bytes
Port
Port
Port
Port
AB11
AB10
AB9
AB8
Up to 4K bytes
Port
Port
AB13
AB12
AB11
AB10
AB9
AB8
Up to 16K bytes
AB15
AB14
AB13
AB12
AB11
AB10
AB9
AB8
Up to 31K/48K/56K/60K
bytesNote
Note 31K (µPD78C18), 48K (µPD78C14/78C14A), 56K (µPD78C12A), 60K (µPD78C11A)
When an external device reference instruction is executed in the 256-byte expansion mode, the µPD78C18/78C14/
78C14A/78C12A/78C11A masks the high-order 8 bits of the 16-bit external reference address, and outputs a value
from 00H to FFH from pins PD7 to PD0 (AD7 to AD0) as address information.
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CHAPTER 11
EXTERNAL DEVICE ACCESSES AND TIMINGS
Similarly, in the 4K-byte expansion mode, the µPD78C18/78C14/78C14A/78C12A/78C11A masks the high-order
4 bits of the 16-bit external reference address, and outputs a value from 000H to FFFH from pins PF3 to PF0 (AB11
to AB8) and pins PD7 to PD0 as address information.
Similarly, in the 16K-byte expansion mode, the µPD78C18/78C14/78C14A/78C12A/78C11A masks the high-order
2 bits of the 16-bit external reference address, and outputs a value from 0000H to 3FFFH from pins PF5 to PF0 (AB13
to AB8) and pins PD7 to PD0 as address information.
As the high-order bits of the 16-bit address are masked in this way in the 256-byte/4K-byte/16K-byte expansion
modes, the external device can be located in any desired 256-byte/4K-byte/16K-byte area in the external 60K-byte
area. However, if, in the 16K-byte expansion mode, external ROM is connected in the expansion area and addresses
1000H to 4FFFH following the on-chip ROM are used as the external ROM area, it should be noted that there will
be the following differences between the program counter (PC) and the address which is actually output from pins
PF5 through PF0 and PD7 through PD0.
1000H
3FFFH
4000H
0000H
…
3FFFH
…
…
PF5-0, PD7-0
…
PC
1000H
4FFFH
0FFFH
When external ROM addresses are used as consecutive addresses, the external ROM area should be set in
addresses 4000H to 7FFFH. Since, in this case, on-chip ROM and external ROM are not in consecutive addresses,
a jump instruction must be used to move the program to the respective areas. The same applies if the external ROM
area is set in addresses 8000H to BFFFH.
Cautions 1. The internal address bus contents are output in all machine cycles to port D when it is
functioning as an address/data bus. Also, the internal address bus contents are output in all
machine cycles from port F pins functioning as an address bus. However, RD and WR signals
are only output in a memory cycle.
2. Software which dynamically changes the operating mode of port D and port F cannot be
emulated by an emulator, and therefore should not be used.
188
Figure 11-1. External Expansion Modes Set by Memory Mapping Register
256-byte
expansion mode
4K-byte
expansion mode
16K-byte
expansion mode
31K/48K/56K/60K-byte
expansion mode
On-chip ROM
(4K/8K/16K/32K
bytes)
On-chip ROM
(4K/8K/16K/32K
bytes)
On-chip ROM
(4K/8K/16K/32K
bytes)
On-chip ROM
(4K/8K/16K/32K
bytes)
On-chip ROM
(4K/8K/16K/32K
bytes)
Not used
External memory
(16K bytes)
0
Not used
External memory
(31K/48K/56K/60K
bytes)
Not used
External memory
(4K bytes)
Not used
External memory
(256 bytes)
Not used
Not used
On-chip RAM
64K
On-chip RAM
On-chip RAM
On-chip RAM
On-chip RAM
EXTERNAL DEVICE ACCESSES AND TIMINGS
,,,
,
,,,
,
,
,
,
,
,
,
,
,
,
,
,
CHAPTER 11
Port mode
189
CHAPTER 11
EXTERNAL DEVICE ACCESSES AND TIMINGS
11.1.1 Memory mapping register (MM)
The memory mapping register is an 8-bit register which performs the following controls:
• Port/expansion mode specification for PD7 to PD0 and PF7 to PF0
• Enabling/disabling of on-chip RAM accesses
• Specification of on-chip EPROM access range (µPD78CP18/78CP14 only: See CHAPTER 12 PROM ACCESSES
(µPD78CP18/78CP14 ONLY))
The configuration of the memory mapping register is shown in Figure 11-2.
(1) Bits MM0 to MM2
These bits control the PD7 to PD0 port/expansion mode and input/output specification, and the PF7 to PF0
address output specification.
As shown in Figure 11-2, there is a choice of four capacities for the connectable external memory:
• 256 bytes
• 4K bytes
• 16K bytes
• 31K/48K/56K/60K bytes:
31K bytes of external expansion memory can be connected to the µPD78C18,
48K bytes to the µPD78C14/78C14A, 56K bytes to the µPD78C12A, and 60K
bytes to the µPD78C11A.
Any of the pins PF7 to PF0 not used as address outputs can be used as general-purpose port pins.
RESET input or the hardware STOP mode resets (0) these bits and sets PD7 to PD0 to input port mode (highimpedance).
(2) MM3 bit (RAE)
This bit controls enabling (RAE=1) and disabling (RAE=0) of on-chip RAM accesses.
This bit should be set to "0" during standby operation and when externally connected RAM and not on-chip
RAM is used.
In normal operation this bit retains its value when RESET is input.
Cautions
1. Overwriting the RAE bit during program execution allows an apparent increase of 256
bytes in the memory space. However, this operation cannot be emulated by an
emulator, and should therefore not be performed.
2. The RAE bit is undefined after a power-on reset, and must therefore be initialized by
an instruction.
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CHAPTER 11
EXTERNAL DEVICE ACCESSES AND TIMINGS
In the µPD78CP18/78CP14, bit MM5 to MM7 are also valid: These are used to specify the access range of the
on-chip EPROM. See CHAPTER 12 PROM ACCESSES (µPD78CP18/78CP14 ONLY) for details.
Figure 11-2. Memory Mapping Register Format (µPD78C18/78C14/78C14A/78C12A/78C11A)
7
6
5
4
3
–
–
–
–
RAE
2
1
0
MM2 MM1 MM0
0
0
0
0
1
Port mode
PD7 to PD0 = Input port
0
PF7 to PF0 = Port mode
Single chip
PD7 to PD0 = Output port
PF7 to PF0 = Port mode
0
1
0
256 bytes
PD7 to PD0 = Expansion
mode
PF7 to PF0 = Port mode
PD7 to PD0
0
1
1
0
0
4K bytes
Expansion mode
1
PF3 to PF0
= Expansion
mode
PF7 to PF4 = Port mode
PD7 to PD0
16K bytes
PF5 to PF0
= Expansion
mode
PF7 & PF6 = Port mode
1
1
1
31K/48K/56K/
60K bytesNote
PD7 to PD0
PF7 to PF0
= Expansion
mode
On-chip RAM access
0
Disable
1
Enable
Note 31K (µPD78C18), 48K (µPD78C14/78C14A), 56K (µPD78C12A), 60K (µPD78C11A)
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CHAPTER 11
EXTERNAL DEVICE ACCESSES AND TIMINGS
11.1.2 Example of memory expansion
Figure 11-3 shows an example of a configuration with 16K bytes of external expansion ROM, and Figure 11-4
shows the data set in the memory mapping register for this configuration.
Figure 11-3. Example of Memory Expansion (Reference Diagram)
VDD
87AD series
MODE1
MODE0
O0~7
Standby
control
STOP
OE µ PD27C512
RD
A0~7
ALE
VDD
LE
VDD
AVDD
PD7-0
(AD7-0)
AD7-0
DI DO
VAREF
OE
PF5-0
(AB13-8)
VSS
AVSS
PF7, 6
System
reset
RESET
X1
X2
Note µPD27C512 uses only 16K bytes.
192
AB13-8
µ PD74HC573
CE
Note
A14, 15
A8~13
CHAPTER 11
EXTERNAL DEVICE ACCESSES AND TIMINGS
Figure 11-4. Memory Mapping Register Settings
MM
7
6
5
4
3
2
1
0
–
–
–
–
RAE
1
1
0
PD7 to PD0 : Expansion mode
PF5 to PF0 : Expansion mode
PF7 & PF6 : Port mode
On-chip RAM access
0
Disable
1
Enable
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CHAPTER 11
EXTERNAL DEVICE ACCESSES AND TIMINGS
11.1.3 Example of peripheral device connection
In the µPD78C18/78C14/78C14A/78C12A/78C11A, a µPD8085 type bus system is used in which the data bus and
low-order 8-bits of the address bus are multiplexed. Therefore, a large number of µPD8085 peripheral devices can
be connected.
When peripheral devices are connected, since the µPD78C18/78C14/78C14A/78C12A/78C11A has no I/O address
space, memory mapped I/O must be used for all of them. The connection of typical peripheral devices is illustrated
here.
Figure 11-5 shows an example of a configuration in which external memory and a parallel interface unit (µPD71055)
are connected. The memory maps for the µPD78C18/78C14/78C14A/78C12A/78C11A when set to the full expansion
mode are shown in Figure 11-6 to 11-9.
An example of the control program for the µPD71055 is shown below.
PPIST ; LXI H, 0C03 H; Set base address
MVI A, 1 0 0 0 0 0 1 1 B
P23 to P20 Input
P17 to P10 Input
Mode 0 Selection
P27 to P24 Output
P07 to P00 Output
Mode 0 Selection
Mode selection
STAX
H
MVI
A, 0F0H
STAX
H
; Set control word (1C03H)
; (C003H)
; Port 2 0F0H output (1C02H)
; (C002H)
MVI
A, 0C3H
MVI
L, 00H
STAX
H
; Port0 0C3H output (1C00H)
… … …
; (C000H)
194
Figure 11-5. µPD71055 Connection Diagram (Reference Diagram)
VDD
µ PD71055
87AD series
µ PD74HC139
PF7
MODE1
B
Y3
MODE0
A
Y2
PF6
CS
G
VDD
PD0
ALE
A0
A1
PD1
PF7
CHAPTER 11
PF7-0
(AB15-8)
Port0
VAREF
PD7-0
(AD7-0)
CS
A14–0
µ PD27C512Note 1
DI DO
OE
Standby
control
CE
LE
AVDD
P17-P10
Port1
µ PD74HC573
OE
O7–0
P27-P20
Port2
µ PD43256Note 2
A15
OE WE
I/O8–1
A14
STOP
D7-D0
VSS
RD
RD
WR
WR
RESET
VDD
AVSS
System
reset
A13–0
RESET
Notes 1. µPD27C512: 16K bytes used with µ PD78C14/78C14A,
24K bytes with µPD78C12A, 28K bytes
with µPD78C11A.
2. µPD43256 : Only 16K bytes used
VDD GND
System
reset
EXTERNAL DEVICE ACCESSES AND TIMINGS
P07-P00
VDD
195
CHAPTER 11
EXTERNAL DEVICE ACCESSES AND TIMINGS
Figure 11-6. Memory Map (µPD78C18)
0000H
On-chip ROM
32K bytes
7FFFH
8000H
External
expansion RAM
16K bytes
BFFFH
C000H
FBFFH
FC00H
External
expansion I/O
On-chip RAMNote
FFFFH
Note Can only be used when the RAE bit of the MM register is "1".
Figure 11-7. Memory Map (µPD78C14/78C14A)
0000H
On-chip ROM
16K bytes
3FFFH
4000H
External
expansion ROM
16K bytes
7FFFH
8000H
External
expansion ROM
16K bytes
BFFFH
C000H
FEFFH
FF00H
External
expansion I/O
On-chip RAMNote
FFFFH
Note Can only be used when the RAE bit of the MM register is "1".
196
CHAPTER 11
EXTERNAL DEVICE ACCESSES AND TIMINGS
Figure 11-8. Memory Map (µPD78C12A)
0000H
On-chip ROM
8K bytes
1FFFH
2000H
External
expansion ROM
24K bytes
7FFFH
8000H
External
expansion RAM
16K bytes
BFFFH
C000H
FEFFH
FF00H
External
expansion I/O
On-chip RAMNote
FFFFH
Note Can only be used when the RAE bit of the MM register is "1".
Figure 11-9. Memory Map (µPD78C11A)
0000H
On-chip ROM
4K bytes
1FFFH
1000H
External
expansion ROM
28K bytes
7FFFH
8000H
External
expansion RAM
16K bytes
BFFFH
C000H
FEFFH
FF00H
External
expansion I/O
On-chip RAM
Note
FFFFH
Note Can only used when the RAE bit of the MM register is "1".
197
CHAPTER 11
EXTERNAL DEVICE ACCESSES AND TIMINGS
11.2 µPD78C17/78C10A External Device Access
As the µPD78C17/78C10A have no on-chip ROM, it is possible to install an external device (program memory,
data memory, or a peripheral device) in an external 63K byte area (0000H to FBFFH)/64K-byte area (0000H to FEFFH)
in addition to on-chip RAM. The address space of an externally installed device is set by the MODE0 and MODE1
pins, with a choice of 4K bytes (addresses 0000H to 0FFFH), 16K bytes (addresses 0000H to 3FFFH), or 63K bytes
(addresses 0000H to FBFFH)/64K bytes (addresses 0000H to FEFFH).
Operation Mode
Control Pins
MODE1 MODE0
External Address Area
On-Chip RAM Area
4K-byte access
0
0
4K bytes (addresses 0000H to 0FFFH)
Address FF00H to FFFFH
16K-byte access
0
1
16K bytes (addresses 0000H to 3FFFH)
Addresses FF00H to FFFFH
1
0
1
1
63K bytes (addresses 0000H to FBFFH)
Addresses FC00H to FFFFH
1
1
64K bytes (addresses 0000H to FEFFH)
Addresses FF00H to FFFFH
–
63K-byte access
Setting Prohibited
(µPD78C17 only)
64K-byte access
(µPD78C10A only)
The external device is accessed using the RD, WR and ALE signals, with pins PD7 to PD0 functioning as a
multiplexed address/data bus (AD7 to AD0) and pins PF7 to PF0 as an address bus (AB15 to AB8). When accessing
a 4K-byte or 16K-byte area external device, pins PF7 to PF0 which are not used as address lines can be used as generalpurpose input/output port pins.
The size of the external address space is determined by the setting of the MODE0 and MODE1 pins.
198
CHAPTER 11
EXTERNAL DEVICE ACCESSES AND TIMINGS
11.2.1 MM register setting
The low-order 3 bits of the µPD78C17/78C10A MM register should be set to "0". The RAE bit controls enabling
and disabling of on-chip RAM accesses. When on-chip RAM is not used and that area is used by externally connected
memory, the RAE bit should be set to "0" to disable on-chip RAM accesses.
In normal operation, the RAE bit retains its current value when RESET signal is input. However, the RAE bit is
undefined after a power-on reset, and must therefore be initialized by an instruction.
Figure 11-10. MM Register Format (µPD78C17/78C10A)
,
,
,,
,
,,
,
,,
,,
MM
7
6
5
4
3
2
1
0
–
–
–
–
RAE
0
0
0
On-chip RAM access
0
Disable
1
Enable
Figure 11-11. µPD78C17 Address Space
4K-byte access
0000H
16K-byte access
0000H
63K-byte access
0000H
External device
0FFFH
,
,
,
,
,
External device
External device
3FFFH
FC00H
FFFFH
On-chip RAM
On-chip RAM
On-chip RAM
MODE0 = 0
MODE1 = 0
MODE0 = 1
MODE1 = 0
MODE0 = 1
MODE1 = 1
199
,
,
,,
,
,,
,,
CHAPTER 11
EXTERNAL DEVICE ACCESSES AND TIMINGS
Figure 11-12. µPD78C10A Address Space
4K-byte access
0000H
16K-byte access
0000H
64K-byte access
0000H
External device
0FFFH
External device
External device
,,
,,
,
3FFFH
FF00H
FFFFH
On-chip RAM
On-chip RAM
On-chip RAM
MODE0 = 0
MODE1 = 0
MODE0 = 1
MODE1 = 0
MODE0 = 1
MODE1 = 1
Cautions 1. Instructions on port D or port F must not be executed in the 64K-byte access mode, as this
will result in an unpredictable operation.
2. A program which dynamically changes the port F input/output mode cannot be emulated by
an emulator, and therefore should not be used.
3. A WR pulse is output if an output instruction is executed on port D or port F in the 64K-byte
mode, and this must therefore on no account be performed.
4. With an emulator, the device may operate normally even if the RAE bit is not initialized by
an instruction.
5. Overwriting the RAE bit during program execution allows an apparent increase of 256 bytes
in the memory space. However, this operation cannot be emulated by an emulator, and should
therefore not be performed.
200
CHAPTER 11
EXTERNAL DEVICE ACCESSES AND TIMINGS
11.3 Timings
µPD78C18 operation timings are shown in Figures 11-13 to 11-15. Three oscillator frequency cycles (from rise
to fall) are defined as one state, represented by Tn.
One machine cycle is completed in 3 states (9 clock cycles) for all normal read and write operations, but 4 states
(12 clock cycles) are required for an OP code fetch.
Wait states (TW) cannot be inserted.
(1) OP code fetch timing (see Figure 11-13)
This is the timing for fetching the OP (operation) code of all instructions, and consists of 4 states, T1 to T4.
The two states T1 and T2 are used for the program memory read, and T3 and T4 are used for internal processing
(decoding).
The upper address signal from the low-order 8 bits of the external memory reference address is output to
AB15 through AB8 (PF7 through PF0) from the start of T1 to the end of T4.
AD7 to AD0 (PD7 to PD0) function as the multiplexed address/data bus: The low-order 8 bits of the external
memory reference address are output during T1, and then AD7 to AD0 become high-impedance.
Since the address information on the AD7 to AD0 bus is only output temporarily, it must be latched by the
external device. In the 87AD series a special timing signal, ALE, is provided for latching AD7 to AD0. The
ALE signal is output in the T1 state of each machine cycle.
A low-level RD signal is output low from midway through the T1 state to the beginning of T4.
(2) External device read timing (see Figure 11-14)
The data read machine cycle when an external device reference instruction is executed consists of T1 to T3.
Except for the absence of T4, the timing for AB15 to AB8 (PF7 to PF0), AD7 to AD0 (PD7 to PD0), and ALE
is the same as an OP code fetch. A low-level RD signal is output from midway through T1 to the beginning
of T3.
(3) External device write timing (see Figure 11-15)
The data write machine cycle when an external device reference instruction is executed consists of 3 states,
T1 to T3.
The address outputs (AB15 to AB8 and AD7 to AD0) and the ALE signal are the same as for the read timing
machine cycle. The write data is output to AD7 through AD0 from the beginning of T2 to the end of T3. To
enable writing to the addressed device, a low-level WR signal is output from midway through T1 to the
beginning of T3.
When PD7 to PD0 are set as the multiplexed address/data bus (AD7 to AD0) and PF7 to PF0 as the address bus
(AB15 to AB8), both the RD signal and the WR signal become high in machine cycles in which the external device
is not accessed. However, the ALE signal is output and the contents of the internal address bus are output directly
to port D and port F.
201
CHAPTER 11
EXTERNAL DEVICE ACCESSES AND TIMINGS
Figure 11-13. OP Code Fetch Timing
T1
T2
T3
T4
Oscillator
frequency
ALE
AB15-8
(PF7-0)
Address (upper)
AD7-0
(PD7-0)
Address (lower)
OP code
RD
Figure 11-14. External Device Read Timing
T1
T2
T3
Oscillator
frequency
ALE
AB15-8
(PF7-0)
AD7-0
(PD7-0)
Address (upper)
Address (lower)
Read data
RD
Figure 11-15. External Device Write Timing
T1
T2
T3
Oscillator
frequency
ALE
AB15-8
(PF7-0)
AD7-0
(PD7-0)
WR
202
Address (upper)
Address (lower)
Write data
CHAPTER 12 PROM ACCESSES (µPD78CP18/78CP14 ONLY)
The µPD78CP18 and µPD78CP14 incorporate 32K-byte and 16K-byte EPROM respectively. Four modes can be
selected for the on-chip EPROM access range by means of bits MM5 to MM7 of the memory mapping register:
• 4K-byte mode
: Access to addresses 0000H to 0FFFH (µPD78C11A mode)
• 8K-byte mode
: Access to addresses 0000H to 1FFFH (µPD78C12A mode)
• 16K-byte mode
: Access to addresses 0000H to 3FFFH (µPD78C14 mode)
• 32K-byte modeNote
: Access to addresses 0000H to 7FFFH (µPD78C18 mode)
Note The 32K-byte mode applies to the µPD78CP18 only.
The configuration of the µPD78CP18/78C14 memory mapping registers is shown in Figures 12-1 and 12-2.
(1) Bits MM0 to MM2
These bits control the PD7 to PD0 port/expansion mode and input/output specification, and the PF7 to PF0
address output specification.
See 11.1.1 Memory mapping register (MM) for details.
(2) MM3 bit (RAE)
This bit controls enabling (RAE=1) and disabling (RAE=0) of on-chip RAM accesses.
See 11.1.1 Memory mapping register (MM) for details.
(3) Bits MM5 to MM7
These bits are used to specify the on-chip EPROM access range.
When STOP or RESET is input, these bits are reset: The µPD78CP18 is set to the 32K-byte mode, and the
µPD78CP14 to the 16K-byte mode.
These bits are valid only in the µPD78CP18/78CP14/78CG14Note: If data is written to these bits in the
µPD78C14/78C12A/78C11A, it is ignored by the CPU. Therefore, programs developed on the µPD78CP18/
78CP14/78CG14 can be transferred directly to mask ROM.
Note The µPD78CG14 is described in APPENDIX A INTRODUCTION TO PIGGYBACK PRODUCT.
203
CHAPTER 12
PROM ACCESSES (µPD78CP18/78CP14 ONLY)
Figure 12-1. Memory Mapping Register Format (µPD78CP18)
5
MM7 MM6 MM5
4
–
3
2
1
0
RAE MM2 MM1 MM0
0
0
0
0
0
1
0
1
0
1
0
0
1
1
1
1
Port mode
6
PD7 to PD0 = Input port
PF7 to PF0 = Port mode
Single chip
PD7 to PD0 = Output port
PF7 to PF0 = Port mode
256 bytes
PD7 to PD0 = Expansion mode
PF7 to PF0 = Port mode
4K bytes
PD7 to PD0  = Expansion mode

PF3 to PF0 
PF7 to PF4 = Port mode
0
16K bytes
PD7 to PD0  = Expansion mode

PF5 to PF0 
PF7 & PF6 = Port mode
1
31K/48K/56K/
60K bytesNote
PD7 to PD0  = Expansion mode

PF7 to PF0 
Expansion mode
7
Note Depending on bits MM7 to MM5
On-chip RAM access
0
Disable
1
Enable
On-chip PROM and on-chip RAM access ranges
MM7 MM6 MM5
On-Chip RAM
Access Range
0
0
0
0000H to 7FFFH
(32K bytes:
µ PD78C18 mode)
FC00H to FFFFH
(1K bytes)
0
0
1
0000H to 3FFFH
(16K bytes:
µ PD78C14 mode)
FF00H to FFFFH
(256 bytes)
0
1
1
0000H to 1FFFH
(8K bytes:
µ PD78C12A mode)
FF00H to FFFFH
(256 bytes)
1
0
1
0000H to 0FFFH
(4K bytes:
µ PD78C11A mode)
FF00H to FFFFH
(256 bytes)
Other than
the above
204
On-Chip PROM
Access Range
Setting prohibited
CHAPTER 12
PROM ACCESSES (µPD78CP18/78CP14 ONLY)
Figure 12-2. Memory Mapping Register Format (µPD78CP14)
MM7 MM6
5
4
–
–
3
2
1
0
RAE MM2 MM1 MM0
0
0
0
0
0
1
0
1
0
1
0
0
1
1
1
1
Port mode
6
PD7 to PD0 = Input port
PF7 to PF0 = Port mode
Single chip
PD7 to PD0 = Output port
PF7 to PF0 = Port mode
256 bytes
PD7 to PD0 = Expansion mode
PF7 to PF0 = Port mode
4K bytes
PD7 to PD0  = Expansion mode

PF3 to PF0 
PF7 to PF4 = Port mode
0
16K bytes
PD7 to PD0  = Expansion mode

PF5 to PF0 
PF7 & PF6 = Port mode
1
48K/56K/
60K bytes Note
PD7 to PD0  = Expansion mode

PF7 to PF0 
Expansion mode
7
Note Depending on setting of bits MM7 & MM6
On-chip RAM access
0
Disable
1
Enable
On-chip EPROM access
0
0
Access to on-chip EPROM addresses
0000H to 3FFFH
( µPD78C14 mode)
0
1
Access to on-chip EPROM addresses
0000H to 1FFFH
( µPD78C12A mode)
1
0
Access to on-chip EPROM addresses
0000H to 0FFFH
( µPD78C11A mode)
1
1
Setting prohibited
205
[MEMO]
206
CHAPTER 13
PROM WRITE AND VERIFY OPERATIONS (µPD78CP18/78CP14 ONLY)
The µPD78CP18 and µPD78CP14 incorporate 32768 × 8-bit and 16384 × 8-bit PROM respectively as program
memory. The pins shown in Table 13-1 are used for write/verify operations on this PROM.
The µPD78CP18/78CP14 program timing is µPD27C256A compatible, and this chapter should be read in conjunction
with documentation on the µPD27C256A.
Table 13-1. Pin Functions in PROM Programming
Pin Name
Function
RESET
Low-level input (in write/verify and read)
MODE0
High-level input (in write/verify and read)
MODE1
Low-level input (in write/verify and read)
VPPNote1
High-voltage input (in write/verify), high-level input (in read)
CENote1
Chip enable input
OENote1
Output enable input
A0Notes1, 2
Address input
A14 to A0Notes1, 3
Address input
A13 to
PF6Note2
O7-O0Note1
VDDNote1
Low-level input (in write/verify and read)
Data input (in write), data output (in verity/read)
Power supply voltage input
Notes 1. These pins correspond to the µPD27C256A.
2. µPD78CP14 only
3. µPD78CP18 only
Cautions 1. The µPD78CP18DW/78CP18KB/78CP14DW/78CP14KB/78CP14R, which are provided with
an erase window, should be fitted with a light-protective cover film when EPROM
erasure is not being performed.
2. The µPD78CP18CW/78CP18GF-3BE/78CP18GQ-36/78CP14CW/78CP14G-36/78CP14GF3BE/78CP14L one-time PROM products are not provided with an erase window, and thus
UV erasure cannot be used on these devices.
207
PROM WRITE AND VERIFY OPERATIONS (µPD78CP18/78CP14 ONLY)
CHAPTER 13
13.1 PROM Programming Operating Modes
The PROM programming operating mode is set as shown in table 13-2. Pins not used for programming should
be connected as shown in Table 13-3.
Table 13-2. PROM Programming Modes
CENote1
OENote1
VPPNote1
VDDNote1
RESET
MODE0
MODE1
PF6Note2
Program
L
H
+12.5 V
+6 V
L
H
L
L
Program verify
H
L
Program inhibit
H
H
Read
L
L
+5 V
+5 V
Output disable
L
H
Standby
H
L/H
Operating Mode
Notes
1. These pins correspond to the µPD27C256A.
2. µPD78CP14 only
Caution When VPP is set to +12.5 V and VDD to +6 V, driving CE and OE low is inhibited.
Table 13-3. Recommended Connection of Unused Pins (In PROM Programming Mode)
Pin Name
Recommended Connection
INT1
Connect to VSS
X1
AN0 to AN7
VAREF
AVDD
AVSS
208
Pins other than the above
Connect to VSS individually via a resistor
X2
Leave open
CHAPTER 13
PROM WRITE AND VERIFY OPERATIONS (µPD78CP18/78CP14 ONLY)
13.2 PROM Writing Procedure
The procedure for writing data to the PROM is as shown below, allowing high-speed writing.
(1) Connect unused pins to VSS with a pull-down resistor. Supply +6 V to the VDD pin and +12.5 V to the VPP pin.
(2) Supply initial address.
(3) Supply write data.
(4) Supply a 1 ms program pulse (active low) to the CE pin.
(5) Verify mode. If written, go to (7); if not written, repeat (3) through (5). If not written after 25 repetitions,
go to (6).
(6) Halt write operation due to defective device.
(7) Supply write data and supply (times repeated in (3) through (5): ×) × 3 ms program pulse (additional write).
(8) Increment address.
(9) Repeat (3) through (8) up to final address.
Figure 13-1. PROM Write/Verify Timing
Repeat X times
Write
Verify
A14-10/PF6-2
A9/NMI
A8/PF0
Address (high-order 7 bits)
A7-0/PA7-0
Address (low-order 8 bits)
Data input
O7-0/PD7-0
Data
output
Additional
write
Data input
VPP
VPP
VIH
VDD+1
VDD
VDD
VIH
CE/PB6
VIL
VIH
OE/PB7
VIL
209
CHAPTER 13
PROM WRITE AND VERIFY OPERATIONS (µPD78CP18/78CP14 ONLY)
13.3 PROM Reading Procedure
PROM contents can be read onto the external data bus (O7 to O0) using the following procedure.
(1) Connect unused pins to GND with a pull-down resistor.
(2) Supply 5 V to the VDD and VPP pins.
(3) Input address of data to be read to pins A14 through A0.
(4) Read mode.
(5) Output data to pins O7 to O0.
The timing for (2) to (5) above is shown in Figure 13-2.
Figure 13-2. PROM Read Timing
A14-10/PF6-2
A9/NMI
A8/PF0
Address input
CE/PB6
OE/PB7
O7-0/PD7-0
210
Data output
CHAPTER 13
PROM WRITE AND VERIFY OPERATIONS (µPD78CP18/78CP14 ONLY)
13.4 Erasure Procedure (Ceramic Package Products Only)
The programmed data contents of the µPD78CP18DW/78CP18KB/78CP14DW/78CP14KB/78CP14R can be erased
by exposure to ultraviolet radiation through the window in the top of the package.
Erasure is possible using ultraviolet light with a wavelength of approximately 250 nm. The exposure required for
complete erasure is 15 W .s/cm2 (UV intensity × erasure time).
Using a commercially available UV lamp (254 nm wavelength, 12 m .W/cm2 intensity), erasure takes approximately
15 to 20 minutes.
Cautions 1. Program contents may also be erased by extended exposure to direct sunlight or fluorescent
light. The contents should therefore be protected by masking the window in the top of the
package with light-shielding cover film.
2. Erasure should normally be carried out at a distance of 2.5 cm or less from the UV lamp.
Remark
The erasure time may be increased due to deterioration of the UV lamp or dirt on the package window.
13.5 One-Time PROM Products Screening
One-time PROM products (µPD78CP18CW/78CP18GF-3BE/78CP18GQ-36/78CP14CW/78CP14G-36/78CP14GF3BE/78CP14L) can not be completely examined for shipment in NEC according to their structure matters. After
needed data is written, screening, in which PROM verification is performed after high temperature storage based
on the conditions below, is recommended.
Storage Temperature
Storage Time
125 °C
24 hours
NEC performs fee-charged service, named "QTOPTM microcontroller", for one-time PROM writing, marking and
screening including verification. For details, contact our salesman.
211
[MEMO]
212
CHAPTER 14
INSTRUCTION SET
14.1 Operand Notation and Description Method
Operands are written in the operand field of an instruction in accordance with the description method for the
operand notation for that instruction (For details, depends on assembler specifications). When there are several items
listed under the description method, one of these is selected. Alphanumeric characters written in upper case and
the symbols "–" and "+" are keywords, and are written in that form.
The relevant numeric value or label is written as immediate data.
213
CHAPTER 14
Notation
INSTRUCTION SET
Description Method
r
r1
r2
V, A, B, C, D, E, H, L
EAH, EAL, B, C, D, E, H, L
A, B, C
sr
sr1
sr2
sr3
sr4
PA, PB, PC, PD, PF, MKH, MKL, ANM, SMH, SML, EOM, ETMM, TMM, MM, MCC, MA,
MB, MC, MF, TXB, TM0, TM1, ZCM
PA, PB, PC, PD, PF, MKH, MKL, ANM, SMH, EOM, TMM, RXB, CR0, CR1, CR2, CR3
PA, PB, PC, PD, PF, MKH, MKL, ANM, SMH, EOM, TMM
ETM0, ETM1
ECNT, ECPT
rp
rp1
rp2
rp3
SP, B, D, H
V, B, D, H, EA
SP, B, D, H, EA
B, D, H
rpa
rpa1
rpa2
rpa3
B, D, H, D+, H+, D–, H–
B, D, H
B, D, H, D+, H+, D–, H–, D+byte, H+A, H+B, H+EA, H+byte
D, H, D++, H++, D+byte, H+A, H+B, H+EA, H+byte
wa
8-bit immediate data
word
byte
bit
16-bit immediate data
8-bit immediate data
3-bit immediate data
f
CY, HC, Z
irf
NMINote, FT0, FT1, F1, F2, FE0, FE1, FEIN, FAD, FSR, FST, ER, OV, AN4, AN5, AN6, AN7,
SB
Note NMI can also be written as FNMI.
Remark
PORT A
PORT B
PORT C
PORT D
PORT F
MODE A
MODE B
MODE C
MODE CONTROL C
MODE F
MEMORY MAPPING
TIMER REG0
TIMER REG1
TIMER MODE
TIMER/EVENT
COUNTER REG0
ETM1 : TIMER/EVENT
COUNTER REG1
ECNT : TIMER/EVENT
COUNTER UPCOUNTER
ECPT : TIMER/EVENT
COUNTER CAPTURE
214
ETMM : TIMER/EVENT
SP
: STACK POINTER
COUNTER MODE
B
: BC
EOM : TIMER/EVENT
D
: DE
COUNTER OUTPUT
H
: HL
MODE
V
: VA
ANM : A/D CHANNEL
EA
: EXTENDED
MODE
ACCUMULATOR
CR0 : A/D
CONVERSION
3. rpa~rpa3 (rp addressing)
CR3 : RESULT0~3
B
: (BC)
TXB
: TX BUFFER
D
: (DE)
RXB : RX BUFFER
H
: (HL)
SMH : SERIAL MODE
D+
: (DE)+
High
H+
: (HL)+
SML : SERIAL MODE
D–
: (DE)–
Low
H–
: (HL)–
MKH : MASK High
D++
: (DE)++
MKL : MASK Low
H++
: (HL)++
ZCM : ZERO CROSS
D+byte : (DE+byte)
MODE
H+A
: (HL+A)
H+B
: (HL+B)
H+EA : (HL+EA)
H+byte : (HL+byte)
~
PA
:
PB
:
PC
:
PD
:
PF
:
MA :
MB :
MC :
MCC :
MF :
MM :
TM0 :
TM1 :
TMM :
ETM0 :
2. rp~rp3 (register pair)
4. f(flag)
CY
HC
Z
: CARRY
: HALF CARRY
: ZERO
5. irf (interrupt flag)
NMI
FT0
FT1
F1
F2
FE0
FE1
FEIN
FAD
FSR
FST
ER
OV
AN4
:
:
:
:
:
:
:
:
:
:
:
:
:
:
NMI INPUT
INTFT0
INTFT1
INTF1
INTF2
INTFE0
INTFE1
INTFEIN
INTFAD
INTFSR
INTFST
ERROR
OVERFLOW
ANALOG
INPUT 4~7
~
1. sr~sr4 (special register)
AN7
SB
: STANDBY
CHAPTER 14
INSTRUCTION SET
14.2 Explanation of Operation Code Symbols
r
R2
0
0
0
0
1
1
1
1
R1
0
0
1
1
0
0
1
1
R0
0
1
0
1
0
1
0
1
S4
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
S3
0
0
0
0
0
0
0
1
1
1
1
1
1
0
0
0
0
0
0
1
1
1
1
0
0
0
0
1
reg
V
A
B
C
D
E
H
L
r1
T2
0
0
0
0
1
1
1
1
r2
r
T1
0
0
1
1
0
0
1
1
T0
0
1
0
1
0
1
0
1
reg
EAH
EAL
B
C
D
E
H
L
sr
S5
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
sr3
U0
0
1
rp
P2
0
0
0
0
1
S2
0
0
0
0
1
1
1
0
0
0
0
1
1
0
0
0
0
1
1
0
0
0
0
0
0
0
0
0
S1
0
0
1
1
0
1
1
0
0
1
1
0
0
0
0
1
1
0
1
0
0
1
1
0
0
1
1
0
S0
0
1
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
Special-reg
PA
PB
PC
PD
PF
MKH
MKL
ANM
SMH
SML
EOM
ETMM
TMM
MM
MCC
MA
MB
MC
MF
TXB
RXB
TM0
TM1
CR0
CR1
CR2
CR3
ZCM
sr4
V0
0
1
Special-reg
ETM0
ETM1
P1
0
0
1
1
0
P0
0
1
0
1
0
reg-pair
SP
BC
DE
HL
EA
rp
rp2 rp3
sr1 sr2
sr
Special-reg
ECNT
ECPT
rp1
Q2 Q1 Q0
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
rpa
A3
0
0
0
0
0
0
0
0
1
1
1
1
1
A2
0
0
0
0
1
1
1
1
0
1
1
1
1
A1
0
0
1
1
0
0
1
1
1
0
0
1
1
A0
0
1
0
1
0
1
0
1
1
0
1
0
1
(BC)
(DE)
(HL)
(DE)+
(HL)+
(DE)–
(HL)–
(DE+byte)
(HL+A)
(HL+B)
(HL+EA)
(HL+byte)
rpa3
C3 C2
0 0
0 0
0 1
0 1
1 0
1 1
1 1
1 1
1 1
C1
1
1
0
0
1
0
0
1
1
C0
0
1
0
1
1
0
1
0
1
addressing
(DE)
(HL)
(DE)++
(HL)++
(DE+byte)
(HL+A)
(HL+B)
(HL+EA)
(HL+byte)
irf
I4
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
1
1
1
I2
0
0
0
0
1
1
1
1
0
0
0
0
1
0
0
0
0
1
I1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
0
1
1
0
I3
0
0
0
0
0
0
0
0
1
1
1
1
1
0
0
0
0
0
addressing
I0
0
1
0
1
0
1
0
1
0
1
0
1
0
0
1
0
1
0
rpa1
rpa
rpa2
INTF
NMI
FT0
FT1
F1
F2
FE0
FE1
FEIN
FAD
FSR
FST
ER
OV
AN4
AN5
AN6
AN7
SB
f
reg-pair
VA
BC
DE
HL
EA
F2
0
0
0
1
F1
0
1
1
0
F0
0
0
1
0
flag
–
CY
HC
Z
215
CHAPTER 14
INSTRUCTION SET
14.3 Instruction Address Addressing
The instruction address is determined by the contents of the program counter (PC), and is normally incremented
(by one for each byte) automatically according to the number of instruction bytes fetched each time an instruction
is executed. However, when an instruction associated with a branch is executed, the jump address information is
loaded into the PC in accordance with the addressing methods shown below, and a jump is performed.
14.3.1 Register addressing
The contents of the BC register pair or the EA accumulator are loaded into the PC and a jump is performed. This
is performed when the following instructions are executed.
JB
CALB
0 7
7
0
C
B
15
8 7
0
15
8 7
0
15
8 7
0
PC
JEA
EA
PC
216
CHAPTER 14
INSTRUCTION SET
14.3.2 Immediate addressing
The immediate data in the 2nd and 3rd bytes of the instruction is loaded into the PC and a jump is performed.
This is performed when the following instructions are executed.
JMP
word
CALL word
.
.
CALF word
In the case of the CALF instruction, the immediate data in the low-order 3 bits of the 1st byte and the 2nd byte
is loaded into the PC.
7
0
CALL or JMP
Low address
High address
15
8 7
0
PC
7
32
0
faH
CALF
faL
15
PC
11 10
87
0
0 0 0 0 1
217
CHAPTER 14
INSTRUCTION SET
14.3.3 Direct addressing
The contents of the memory addressed by the immediate data in the low-order 5 bits of the operation code are
loaded into the PC and a jump is performed. This is performed when the following instruction is executed.
CALT word
7 6 5 4
Operation code
1 0 0
0
ta
15
Effective address =
8 7 6 5
0 0 0 0 0 0 0 0
1 0
1 0
ta
0
Memory
Low address
High address
Effective address
Effective address + 1
15
87
0
PC
14.3.4 Relative addressing
The result of adding the immediate data (displacement value: jdisp1) in the low-order 6 bits of the operation code
to the start address of the next instruction is loaded into the PC and a jump is performed. The displacement value
is handled as signed two's complement data (–32 to +31), with bit 5 as the sign bit. This is performed when the
following instruction is executed.
JR word
7 6 5
Operation code 1 1
0
jdisp1
15
0
PC + 1
+
15
6 5 4
0
S







X
jdisp1
15
0
PC
S = 0: X = AII 0's
S = 1: X = AII 1's
218
CHAPTER 14
INSTRUCTION SET
14.3.5 Extended relative addressing
The result of adding the 9-bit immediate data (displacement value: jdisp) in the instruction to the start address
of the next instruction is loaded into the PC and a jump is performed. The displacement value is handled as signed
two's complement data (–256 to +255), with bit 8 (bit 0 of the 1st byte of the operation code) as the sign bit. This
is performed when the following instruction is executed.
JRE word
0 1 0 0 1 1 1 jH
jdispL
15
0
PC + 2
+
15
9 8 7
0
S













X
jdisp
15
0
PC
S = 0: X = AII 0's
S = 1: X = AII 1's
219
CHAPTER 14
INSTRUCTION SET
14.4 Operand Address Addressing
There are several methods (addressing methods), as described below, for specifying the register, memory etc.
to be manipulated when executing an instruction.
14.4.1 Register addressing
With this addressing method, the register to be manipulated is specified by the contents of the register
specification code (R2R1R0, T2T1T0, S5S4S3S2S1S0, etc.) in the instruction.
Register addressing is used when an instruction with the following operand formats is executed. In some cases
an 8-bit register is specified, and in others a register pair (16 bits) is specified.
Notation
Description Method
r
V, A, B, C, D, E, H, L
r1
EAH, EAL, B, C, D, E, H, L
r2
A, B, C
sr
PA, PB, PC, PD, PF, MKH, MKL, ANM, SMH, SML, EOM, ETMM, TMM,
MM, MCC, MA, MB, MC, MF, TXB, TM0, TM1, ZCM
sr1
PA, PB, PC, PD, PF, MKH, MKL, ANM, SMH, EOM, TMM, RXB, CR0, CR1,
CR2, CR3
sr2
PA, PB, PC, PD, PF, MKH, MKL, ANM, SMH, EOM, TMM
sr3
ETM0, ETM1
sr4
ECNT, ECPT
rp
SP, B, D, H
rp1
V, B, D, H, EA
rp2
SP, B, D, H, EA
rp3
B, D, H
f
CY, HC, Z
irf
NMINote, FT0, FT1, F1, F2, FE0, FE1, FEIN, FAD, FSR, FST, ER, OV, AN4, AN5, AN6,
AN7, SB
Note NMI can also be written as FNMI.
220
CHAPTER 14
Examples 1.
INSTRUCTION SET
MOV rl, A
Operation code
7
6
5
4
3
2
1
0
0
0
0
1
1
T2
T1
T0
If the E register is selected as r1, the instruction is written as shown below. The part after the
semicolon (;) is a comment and has no effect on the operation of the instruction.
MOV E, A; E ← A
The corresponding operation code is shown below.
Operation code
2.
0
0
0
1
1
1
0
1
0
0
P1
P0
0
0
1
1
DCX rp
Operation code
If the HL register pair selected as rp, the instruction is written as shown below.
DCX H; HL ← HL – 1
The corresponding operation code is as shown below.
Operation code
0
0
1
1
0
0
1
1
221
CHAPTER 14
INSTRUCTION SET
14.4.2 Register indirect addressing
With this addressing method, the memory to be manipulated is addressed using the contents of the register pair
specified by the register pair specification code (A3A2A1A0, C3C2C1C0) in the instruction as the operand address.
Register indirect addressing is used when an instruction with the following operand formats is executed. Items
with auto-increment/decrement, double auto-increment, base and base index functions are described separately.
Notation
Description Method
rpa
B, D, H, D+, H+, D–, H–
rpa1
B, D, H
rpa2
B, D, H, D+, H+, D–, H–, D+byte, H+A, H+B, H+EA, H+byte
rpa3
D, H, D++, H++, D+byte, H+A, H+B, H+EA, H+byte
Example
1.
LDAX rpa2
Operation code
A3 0
1
0
1
A2 A1 A0
If the BC register pair is selected as rpa2, the instruction is written as shown below.
LDAX B; A ← (BC)
The corresponding operation code is shown below.
Operation code
222
0
0
1
0
1
0
0
1
CHAPTER 14
INSTRUCTION SET
14.4.3 Auto-increment addressing
This is a special mode of register indirect addressing using the HL and DE register pairs, in which, after the memory
to be manipulated is addressed using the contents of the register pair specified by the addressing specification code
(A3A2A1A0) in the instruction as the operand address, the contents of that register pair are automatically incremented
by 1, thus preparing for the next addressing operation.
Auto-increment addressing is used when an instruction with the following operand formats is executed.
Notation
Description Method
rpa
D+, H+
rpa2
D+, H+
Examples 1.
STAX rpa2
Operation code
A3 0
1
1
1
A2 A1 A0
If the auto-increment mode is selected for the DE register pair used as rpa2, the instruction is
written as shown below.
STAX D+; (DE) ← A, DE ← DE + 1
The corresponding operation code is shown below.
Operation code
0
0
1
1
1
1
0
0
2. Execution of the BLOCK instruction
Although not specified by an operand, when the BLOCK instruction is executed, the HL register pair
is automatically selected as the source address register and the DE register pair as the destination
address register. After the data transfer from the source address to the destination address has been
performed, the HL and the DE register pairs are both automatically incremented by 1.
BLOCK ; (DE) ← (HL), DE ← DE + 1, HL ← HL + 1
3. Execution of a return instruction on POP instruction
Although not specified by an operand, when a return instruction or POP instruction which restores
data saved to the stack area is executed, auto-incrementing of the stack pointer (SP) is performed.
RET; PCL ← (SP), PCH ← (SP+1), SP ← SP + 2
223
CHAPTER 14
INSTRUCTION SET
14.4.4 Auto-decrement addressing
This is a special mode of register indirect addressing using the HL and DE register pairs, in which, after the memory
to be manipulated is addressed using the contents of the register pair specified by the addressing specification code
(A3A2A1A0) in the instruction as the operand address, the contents of that register pair are automatically decremented
by 1, thus preparing for the next addressing operation.
Auto-decrement addressing is used when an instruction with the following operand formats is executed.
Notation
Description Method
rpa
D–, H–
rpa2
D–, H–
Examples 1.
ADDX rpa
Operation code
0
1
1
1
0
0
0
0
1
1
0
0
0
A2 A1 A0
If the auto-decrement mode is selected for the HL register pair used as rpa, the instruction is
written as shown below.
ADDX H–; A ← A + (HL), HL ← HL –1
The corresponding operation code is shown below.
Operation code
2.
0
1
1
1
0
0
0
0
1
1
0
0
0
1
1
1
Interrupt generation or execution of a CALL instruction or PUSH instruction
Although not specified by an operand, when an interrupt is generated or a CALL instruction or
PUSH instruction is executed, in all of which cases register contents are stored in the stack,
auto-decrementing of the stack pointer (SP) is performed.
SOFTI ;
(SP–1) ← PSW, (SP–2) ← PC+1H
(SP–3) ← PC+1L, PC ← 0060H
224
CHAPTER 14
INSTRUCTION SET
14.4.5 Double auto-increment addressing
This is a special mode of register indirect addressing using the HL and DE register pairs, which is effective for
16-bit data transfers between the extended accumulator (EA) and memory. With double auto-increment addressing,
after the memory to be manipulated is addressed using the contents of the register pair specified by the addressing
specification code (C3C2C1C0) in the instruction as the operand address, the contents of that register pair are
automatically incremented by 2, thus preparing for the next addressing operation.
Double auto-increment addressing is used when an instruction with the following operand format is executed.
Notation
Description Method
rpa3
D++, H++
Example
1.
STEAX rpa3
Operation code
0
1
0
0
1
0
0
0
1
0
0
1
C3 C2 C1 C0
If the double auto-increment mode is selected for the HL register pair used as rpa3, the
instruction is written as shown below.
STEAX H++; (HL) ← EAL, (HL+1) ← EAH, HL ← HL+2
The corresponding operation code is shown below.
Operation code
0
1
0
0
1
0
0
0
1
0
0
1
0
1
0
1
225
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INSTRUCTION SET
14.4.6 Base addressing
This is a special mode of register indirect addressing using the HL and DE register pairs, in which the memory
to be manipulated is addressed using as the operand address the sum of the contents of the register pair (base
register) specified by the addressing specification code (A3A2A1A0, C3C2C1C0) in the instruction, and the immediate
data of the operand (displacement value). Base addressing is used when an instruction with the following operand
formats is executed.
The immediate data (displacement value) is handled as a non-negative number.
Notation
Description Method
rpa2
D+byte, H+byte
rpa3
D+byte, H+byte
Example
1.
STAX rpa2
Operation code
A3 0
1
1
1
A2 A1 A0
Data
If base addressing is selected using the sum of the HL register pair and 10H as rpa2, the
instruction is written as shown below.
STAX H + 10H; (HL + 10H) ← A
Operation code
226
1
0
1
1
1
1
1
1
0
0
0
1
0
0
0
0
CHAPTER 14
INSTRUCTION SET
14.4.7 Base index addressing
This is a special mode of register indirect addressing using the HL and DE register pairs, in which the memory
to be manipulated is addressed using as the operand address the sum of the contents of the register pair (base
register) specified by the addressing specification code (A3A2A1A0, C3C2C1C0) in the instruction, and a register (A,
B, EA). Base index addressing is used when an instruction with the following operand formats is executed.
The register A/B data is handled as a non-negative number.
Notation
Description Method
rpa2
H+A, H+B, H+EA
rpa3
H+A, H+B, H+EA
Example
1.
LDAX rpa2
Operation code
A3 0
1
0
1
A2 A1 A0
If base index addressing is selected using the sum of the HL register pair and the B register
as rpa2, the instruction is written as shown below.
LDAX H + B; A ← (HL + B)
The corresponding operation code is shown below.
Operation code
1
0
1
0
1
1
0
1
227
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INSTRUCTION SET
14.4.8 Working register addressing
With this addressing method, a working register in the memory area to be manipulated is selected with the working
register vector register (V) as the high-order 8 bits of the address and the 8-bit immediate data in the instruction as
the low-order 8 bits of the address. This kind of addressing combines register indirect addressing by the V register
and direct addressing by the immediate data wa.
Working register addressing is used when an instruction with the following operand format is executed.
Notation
Description Method
wa
Label, numeric value up to 8 bits
Example
1.
DCRW wa
Operation code
0
0
1
1
0
0
0
0
Offset
If 77H is specified as wa, the instruction is written as shown below.
DCRW 77H
The corresponding operation code is shown below.
Operation code
0
0
1
1
0
0
0
0
0
1
1
1
0
1
1
1
If the contents of the V register are assumed to be 20H, the generated operand address will
be 2077H, and the contents of the working register in that address will be decremented by 1.
228
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INSTRUCTION SET
14.4.9 Accumulator indirect addressing
This is a special example of register indirect addressing in which the contents of the memory addressed by PC
+ 3 + A are loaded into the C register, and the contents of the memory addressed by PC + 3 + A + 1 are loaded
into the B register.
Accumulator indirect addressing is used when the TABLE instruction is executed.
Example
1.
Assuming the accumulator contents to be 0 and the PC contents to be 100H, the operation is
as follows:
TABLE; C ← (103H), B ← (104H)
14.4.10 Immediate addressing
This addressing method has 1-byte operand data for manipulation in the operation code. Immediate addressing
is used when an instruction with the following operand format is executed.
Notation
Description Method
byte
Label, numeric value up to 8 bits
Example
1.
ADI A, byte
Operation code
0
1
0
0
0
1
1
0
Data
If 79H is used as "byte", the instruction is written as shown below.
ADI A, 79H; A ← A + 79H
The corresponding operation code is shown below.
Operation code
0
1
0
0
0
1
1
0
0
1
1
1
1
0
0
1
229
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INSTRUCTION SET
14.4.11 Extended immediate addressing
This addressing method has 2-byte operand data for manipulation in the operation code. Extended immediate
addressing is used when an instruction with the following operand format is executed.
Notation
Description Method
word
Label, numeric value up to 16 bits
Example
1.
LXI rp2, word
Operation code
0
P2
P1
P0
0
1
0
0
Low byte
High byte
If HL is used as rp2 and 3F54H as "word", the instruction is written as shown below.
LXI H, 3F54H; HL ← 3F54H
The corresponding operation code is shown below.
Operation code
230
0
0
1
1
0
1
0
0
0
1
0
1
0
1
0
0
0
0
1
1
1
1
1
1
CHAPTER 14
INSTRUCTION SET
14.4.12 Direct addressing
With this addressing method, the memory to be manipulated is addressed using the immediate data in the
instruction as the operand address. Direct addressing is used when an instruction with the following operand format
is executed.
Notation
Description Method
word
Label, numeric value up to 16 bits
Example
1.
MOV r, word
Operation code
0
1
1
1
0
0
0
0
0
1
1
0
1
R2 R1 R0
Low address
High address
If the B register is used as r and EEFFH as "word", the instruction is written as shown below.
MOV B, 0EEFFH;
The corresponding operation code is shown below.
Operation code
0
1
1
1
0
0
0
0
0
1
1
0
1
0
1
0
1
1
1
1
1
1
1
1
1
1
1
0
1
1
1
0
231
Example
2.
CHAPTER 14
INSTRUCTION SET
0
1
1
1
0
0
0
0
0
0
1
0
1
1
1
0
SDED word
Operation code
Low address
High address
If the label DST is used as "word", the instruction is written as shown below.
SDED DST
If DST is assumed to be 4000H, the corresponding operation code is as follows:
Operation code
0
1
1
1
0
0
0
0
0
0
1
0
1
1
1
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
14.5 Number of States Required for Skipping
The number in parentheses indicated in "<3> Number of states" in the instruction set descriptions is the number
of idle states consumed without any operation when that instruction is skipped.
The number of idle states when the instruction is skipped is 4 in the case of the OP code and 3 in the case of
immediate data.
Example MVI sr2, byte instruction (3-byte instruction)
0
1
1
0
0
1
0
0
S3
0
0
0
0
S2
S1
S0
Data
As the 1st and 2nd bytes are the OP code the number of idle states is 4, and as the 3rd byte is immediate
data, the number of idle states is 3.
Therefore, the number of idle states consumed when this instruction is skipped is 4 + 4 + 3 = 11.
232
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INSTRUCTION SET
14.6 Instruction Descriptions
14.6.1 8-bit data transfer instructions
MOV r1, A
(Move A to Register)
<1> Operation code
:
0
<2> Number of bytes :
1
0
<3> Number of states :
4 (4)
<4> Function
r1 ← A
:
0
1
1
T2
T1
T0
Transfers the accumulator contents to register r1 (EAH, EAL, B, C, D, E, H, L) specified by T2T1T0 (0 to 7).
When EAH is specified by r1 the contents are transferred to the high-order 8 bits of the extended accumulator,
and when EAL is specified, to the low-order 8 bits.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
MOV B, A; Transfer A to B.
:
0
<2> Number of bytes :
1
<3> Number of states :
4 (4)
<4> Function
A ← r1
MOV A, r1
(Move Register to A)
<1> Operation code
:
0
0
0
1
T2
T1
T0
Transfers the contents of register r1 (EAH, EAL, B, C, D, E, H, L) specified by T2T1T0 (0 to 7) to the accumulator.
When EAH is specified by r1 the contents of the high-order 8 bits of the extended accumulator are transferred
to the accumulator, and when EAL is specified the low-order 8 bits of the extended accumulator are
transferred.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
MOV A, C; Transfer C to A.
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INSTRUCTION SET
MOV sr, A
(Move A to Special Register)
<1> Operation code
:
0
1
0
0
1
1
0
1
1
1
S5
S4
S3
S2
S1
S0
<2> Number of bytes :
2
<3> Number of states :
10 (7)
<4> Function
sr ← A
:
Transfers the accumulator contents to the special register sr (PA, PB, PC, PD, PF, MKH, MKL, ANM, SMH,
SML, EOM, ETMM, TMM, MM, MCC, MA, MB, MC, MF, TXB, TM0, TM1, ZCM) specified by S5S4S3S2S1S0
(0 to 3, 5 to D, 10 to 14, 17, 18, 1A, 1B, 28).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
MOV PA, A; Transfer A to port A latch.
MOV A, sr1
(Move Special Register to A)
<1> Operation code
:
0
1
0
0
1
1
0
0
1
1
S5
S4
S3
S2
S1
S0
<2> Number of bytes :
2
<3> Number of states :
10 (7)
<4> Function
A ← sr1
:
Transfers the contents of the special register sr1 (PA, PB, PC, PD, PF, MKH, MKL, ANM, SMH, EOM, TMM,
RXB, CR0, CR1, CR2, CR3) specified by S5S4S3S2S1S0 (0 to 3, 5 to 9, B, D, 19, 20 to 23) to the accumulator.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
MOV A TMM; Transfer timer mode register contents to A.
234
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INSTRUCTION SET
MOV r, word
(Move Memory to Register)
<1> Operation code
:
0
1
1
1
0
0
0
0
0
1
1
0
1
R2 R1 R0
Low address
High address
<2> Number of bytes :
4
<3> Number of states :
17 (14)
<4> Function
r ← (word)
:
Transfers the contents of the memory addressed by the 3rd byte (Low address) and 4th byte (High address)
to the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
MOV B, 89ABH; Transfer contents of address 89ABH to B.
MOV word, r
(Move Register to Memory)
<1> Operation code
:
0
1
1
1
0
0
0
0
0
1
1
1
1
R2 R1 R0
Low address
High address
<2> Number of bytes :
4
<3> Number of states :
17 (14)
<4> Function
(word) ← r
:
Transfers the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7) to the memory
addressed by the 3rd byte (Low address) and 4th byte (High address).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
MOV EXAM, A; Transfer A to memory addressed by label EXAM.
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INSTRUCTION SET
MVI r, byte
(Move Immediate to Register)
<1> Operation code
:
0
1
1
0
1
R2 R1 R0
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
r ← byte
:
Transfers the immediate data in the 2nd byte (Data) to the register r (V, A, B, C, D, E, H, L) specified by R2R1R0
(0 to 7). Has a stacking effect when A or L is specified as r.
<5> Flags affected
:
SK ← 0, L1 ← 1, L0 ← 0 (when r = A)
SK ← 0, L1 ← 0, L0 ← 1 (when r = L)
SK ← 0, L1 ← 0, L0 ← 0 (other cases)
<6> Example
:
MVI D, 0AFH; Load AFH into the D register.
MVI sr2, byte
(Move Immediate to Special Register)
<1> Operation code
:
0
1
1
0
0
1
0
0
S3 0
0
0
0
S2
S1
S0
Data
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
sr2 ← byte
:
Transfers the immediate data in the 3rd byte to the special register sr2 (PA, PB, PC, PD, PF, MKH, MKL,
ANM, SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D).
<5> Flags affected
236
:
SK ← 0, L1 ← 0, L0 ← 0
CHAPTER 14
INSTRUCTION SET
MVIW wa, byte
(Move Immediate to Working Register)
<1> Operation code
:
0
1
1
1
0
0
0
1
Offset
Data
<2> Number of bytes :
3
<3> Number of states :
13 (10)
<4> Function
(V.wa) ← byte
:
Transfers the immediate data (Data) in the 3rd byte to the working register addressed by the V register
(specifying the high-order 8 bits of the memory address) and the 2nd byte (specifying the low-order 8 bits).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
MVIV, 00H, 20H; Store 20H in working register in address 4000H.
MVIX rpa1, byte
(Move Immediate to Memory addressed by Register Pair)
<1> Operation code
:
0
1
0
0
1
0
A1 A0
Data
<2> Number of bytes :
2
<3> Number of states :
10 (7)
<4> Function
(rpa1) ← byte
:
Transfers the immediate data (Data) in the 2nd byte to the memory addressed by the register pair rpa1 (BC,
DE, HL) specified by A1A0 (1 to 3).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
MVIX B, 00H; Store 0 in memory addressed by the BC register pair.
237
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INSTRUCTION SET
STAW wa
(Store A to Working Register)
<1> Operation code
:
0
1
1
0
0
0
1
1
Offset
<2> Number of bytes :
2
<3> Number of states :
10 (7)
<4> Function
(V. wa) ← A
:
Stores the accumulator contents in the working register addressed by the V register (specifying the highorder 8 bits of the memory address) and the 2nd byte (specifying the low-order 8 bits).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
MVI V, 0EEH
STAW 0FFH ; Store A in address EEFFH.
LDAW wa
(Load A With Working Register)
<1> Operation code
:
0
0
0
0
0
0
0
1
Offset
<2> Number of bytes :
2
<3> Number of states :
10 (7)
<4> Function
A ← (V. wa)
:
Loads the contents of the working register addressed by the V register (specifying the high-order 8 bits of
the memory address) and the 2nd byte (specifying the low-order 8 bits) into the accumulator.
<5> Flags affected
238
:
SK ← 0, L1 ← 0, L0 ← 0
CHAPTER 14
INSTRUCTION SET
STAX rpa2
(Store A to Memory addressed by Register Pair)
<1> Operation code
:
A3 0
1
1
1
A2 A1 A0
Data
<2> Number of bytes/states:
The number of bytes and number of states are as shown below, depending on the rpa2 specification.
rpa2
B
D
H D+ H+ D– H–
Number of bytes
1
Number of states
7 (4)
<3> Function
:
D+byte
H+A
2
H+B
1
H+EA
H+byte
2
13 (7)
(rpa2) ← A
Stores the accumulator contents in the memory addressed by the register pair rpa2 (BC, DE, HL, DE+, HL+,
DE–, HL–, DE+byte, HL+A, HL+B, HL+EA, HL+byte) specified by A3A2A1A0 (1 to 7, B to F). If auto-increment/
auto-decrement is specified, the contents of the register pair (DE or HL) are automatically incremented or
decremented by 1 after the accumulator contents have been stored.
If DE+byte or HL+byte is specified as rpa2, the memory is addressed by the result of adding the 2nd byte
(Data) of the instruction to the contents of DE/HL. If HL+A, HL+B, or HL+EA is specified, the memory is
addressed by the result of adding the contents of the register (A, B, EA) to the contents of HL.
<4> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<5> Example
:
LXI
…
D, 4000H ; DE ← 4000H
STAX
D+
; (4000H) ← A, DE ← 4001H
STAX
D+10H
; (4011H) ← A, DE ← 4001H
This example stores A in addresses 4000H and 4011H.
239
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INSTRUCTION SET
LDAX rpa2
(Load A with Memory addressed by Register Pair)
<1> Operation code
:
A3 0
1
0
1
A2 A1 A0
Data
<2> Number of bytes/states:
The number of bytes and number of states are as shown below, depending on the rpa2 specification.
rpa2
B
D
H D+ H+ D– H–
Number of bytes
1
Number of states
7 (4)
<3> Function
:
D+byte
2
H+A
H+B
H+EA
1
H+byte
2
13 (7)
A ← (rpa2)
Loads the contents of the memory addressed by the register pair rpa2 (BC, DE, HL, DE+, HL+, DE–,
HL–, DE+byte, HL+A, HL+B, HL+EA, HL+byte) specified by A3A2A1A0 (1 to 7, B to F) into the accumulator.
If auto-increment/auto-decrement is specified, the contents of the register pair (DE or HL) are automatically
incremented or decremented by 1 after the accumulator has been loaded.
If DE+byte or HL+byte is specified as rpa2, the memory is addressed by the result of adding the 2nd byte
(Data) of the instruction to the contents of DE/HL. If HL+A, HL+B, or HL+EA is specified, the memory is
addressed by the result of adding the contents of the register (A, B, EA) to the contents of HL.
<4> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<5> Example
:
LXI
…
H, 4000H ; HL ← 4000H
MVI
B, 20H
; B ← 20H
LDAX
H+B
; A ← (4020H)
This example loads the contents of address 4020H into A.
EXX
(Exchange Register Sets)
<1> Operation code
:
0
<2> Number of bytes :
1
<3> Number of states :
4 (4)
<4> Function
→
→
→
→
→
B→
← B', C ←C', D ←D', E ←E', H ←H', L ←L'
:
0
0
1
0
0
0
1
Exchanges the contents of registers B, C, D, E, H, L with the contents of registers B', C', D', E', H', L'.
<5> Flags affected
240
:
SK ← 0, L1 ← 0, L0 ← 0
CHAPTER 14
INSTRUCTION SET
EXA
(Exchange V, A, EA and V', A', EA')
<1> Operation code
:
0
0
<2> Number of bytes :
1
<3> Number of states :
4 (4)
0
1
0
0
0
0
→
→
V→
← V', A ← A', EA ← EA'
Exchanges the contents of V and A registers and EA with the contents of the V' and A' registers and EA'.
<4> Function
:
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
:
0
<2> Number of bytes :
1
<3> Number of states :
4 (4)
→
H→
← H', L ← L'
EXH
(Exchange HL and H'L')
<1> Operation code
<4> Function
:
1
0
1
0
0
0
0
Exchanges the contents of H and L registers with the contents of the H' and L' registers.
:
SK ← 0, L1 ← 0, L0 ← 0
:
0
<2> Number of bytes :
1
<5> Flags affected
BLOCK
(Block Data Transfer)
<1> Operation code
0
1
1
0
0
0
1
<3> Number of states :
13 × (C+1), (4)
<4> Function
(DE) ← (HL), DE ← DE+1, HL ← HL+1, C ← C–1, end if borrow.
:
Performs a block transfer to the memory addressed by the DE register pair comprising the number of bytes
specified by the C register used as a counter (C register value +1) of the contents of the memory addressed
by the HL register pair.
Each time a byte is transferred, HL and DE are auto-incremented and the C register is decremented. When
the C register value reaches FFH, the instruction is terminated and the program moves on to the next
instruction.
Interrupts can be acknowledged during repeated transfers by means of a BLOCK instruction, in which case
the transfer continues after returning from the interrupt service routine.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
241
CHAPTER 14
INSTRUCTION SET
14.6.2 16-bit data transfer instructions
DMOV rp3, EA
(Move EA to Register Pair)
<1> Operation code
:
1
<2> Number of bytes :
1
0
1
1
0
1
<3> Number of states :
4 (4)
<4> Function
rp3L ← EAL, rp3H ← EAH
:
P1
P0
Transfers the contents of the lower half (EAL) of the extended accumulator to the lower register (C, E, L)
of the register pair rp3 (BC, DE, HL) specified by P1P0 (1 to 3), and the contents of the upper half (EAH) to
the upper register (B, D, H) of the register pair.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
DMOV B, EA; C ← EAL, B ← EAH
DMOV EA, rp3
(Move Register Pair to EA)
<1> Operation code
:
1
<2> Number of bytes :
1
<3> Number of states :
4 (4)
<4> Function
EAL ← rp3L, EAH ← rp3H
:
0
1
0
0
1
P1
P0
Transfers the contents of the lower register (C, E, L) of the register pair rp3 (BC, DE, HL) specified by P1P0
(1 to 3) to the lower half (EAL) of the extended accumulator, and the contents of the upper register (B, D,
H) of the register pair to the upper half (EAH).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
DMOV EA, B; EAL ← C, EAH ← B
DMOV sr3, EA
(Move EA to Special Register)
<1> Operation code
:
0
1
0
0
1
0
0
0
1
1
0
1
0
0
1
U0
<2> Number of bytes :
2
<3> Number of states :
14 (8)
<4> Function
sr3 ← EA
:
Transfers the extended accumulator contents to the special register sr3 (ETM0, ETM1) specified by U0 (0,
1).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
DMOV ETM0, EA; Transfer EA to ETM0.
242
CHAPTER 14
INSTRUCTION SET
DMOV EA, sr4
(Move Special Register to EA)
<1> Operation code
:
0
1
0
0
1
0
0
0
1
1
0
0
0
0
0
V0
<2> Number of bytes :
2
<3> Number of states :
14 (8)
<4> Function
EA ← sr4
:
Transfers the contents of the special register sr4 (ECNT, ECPT) specified by V0 (0, 1) to the extended accumulator.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
:
0
1
1
1
0
0
0
0
0
0
0
1
1
1
1
0
SBCD word
(Store B&C Direct)
<1> Operation code
Low address
High address
<2> Number of bytes :
4
<3> Number of states :
20 (14)
<4> Function
(word) ← C, (word+1) ← B
:
Stores the contents of the C register in the memory addressed by the 3rd byte (lower address) and 4th byte
(upper address), and stores the contents of the B register in the next memory address.
<5> Flags affected
<6>
Example
:
SK ← 0, L1 ← 0, L0 ← 0
:
SBCD 4000H; Store C register contents in address 4000H, and store B register
; contents in address 4001H.
SDED word
(Store D&E Direct)
<1> Operation code
:
0
1
1
1
0
0
0
0
0
0
1
0
1
1
1
0
Low address
High address
<2> Number of bytes :
4
<3> Number of states :
20 (14)
<4> Function
(word) ← E, (word+1) ← D
:
Stores the contents of the E register in the memory addressed by the 3rd byte (lower address) and 4th byte
(upper address), and stores the contents of the D register in the next memory address.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
243
CHAPTER 14
INSTRUCTION SET
SHLD word
(Store H&L Direct)
<1> Operation code
:
0
1
1
1
0
0
0
0
0
0
1
1
1
1
1
0
Low address
High address
<2> Number of bytes :
4
<3> Number of states :
20 (14)
<4> Function
(word) ← L, (word+1) ← H
:
Stores the contents of the L register in the memory addressed by the 3rd byte (lower address) and 4th byte
(upper address), and stores the contents of the H register in the next memory address.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
:
0
1
1
1
0
0
0
0
0
0
0
0
1
1
1
0
SSPD word
(Store SP Direct)
<1> Operation code
Low address
High address
<2> Number of bytes :
4
<3> Number of states :
20 (14)
<4> Function
(word) ← SPL, (word+1) ← SPH
:
Stores the low-order 8 bits (SPL) of the stack pointer in the memory addressed by the 3rd byte (lower address)
and 4th byte (upper address), and stores the high-order 8 bits (SPH) in the next memory address.
<5> Flags affected
244
:
SK ← 0, L1 ← 0, L0 ← 0
CHAPTER 14
INSTRUCTION SET
STEAX rpa3
(Store EA to Memory addressed by Register Pair)
<1> Operation code
:
0
1
0
0
1
0
0
0
1
0
0
1
C3 C2 C1 C0
Data
<2> Number of bytes/states:
The number of bytes and number of states are as shown below, depending on the rpa3 specification.
rpa3
D
H
D++
Number of bytes
2
Number of states
14 (8)
<3> Function
:
H++
D+byte
3
H+A
H+B
H+EA
2
H+byte
3
20 (11)
(rpa3) ← EAL, (rpa3+1) ← EAH
Stores the contents of the low-order 8 bits (EAL) of the extended accumulator in the memory addressed
by the register pair rpa3 (DE, HL, DE++, HL++, DE+byte, HL+A, HL+B, HL+EA, HL+byte) specified by
C3C2C1C0 (2 to 5, B to F), and stores the contents of the high-order 8 bits (EAH) in the memory addressed
by rpa3 + 1.
If DE+byte or HL+byte is specified as rpa3, memory is addressed by the result of adding the 3rd byte (Data)
of the instruction to the contents of DE/HL. If HL+A, HL+B, or HL+EA is specified, the memory is addressed
by the result of adding the contents of the register (A, B, EA) to the contents of HL.
<4> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<5> Example
:
LXI
D, 4000H ; DE ← 4000H
STEAX D++
; (4000H) ← EAL, (4001H) ← EAH
; DE ← 4002H
STEAX D+10H
; (4012H) ← EAL, (4013H) ← EAH
; DE=4002H
This example stores the low-order 8 bits (EAL) of the extended accumulator in address 4000H and address
4012H, and stores the high-order 8 bits (EAH) in address 4001H and address 4013H.
245
CHAPTER 14
INSTRUCTION SET
LBCD word
(Load B&C Direct)
<1> Operation code
:
0
1
1
1
0
0
0
0
0
0
0
1
1
1
1
1
Low address
High address
<2> Number of bytes :
4
<3> Number of states :
20 (14)
<4> Function
C ← (word), B ← (word+1)
:
Loads the contents of the memory addressed by the 3rd byte (lower address) and 4th byte (upper address)
into the C register, and loads the contents of the next memory address into the B register.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
:
0
1
1
1
0
0
0
0
0
0
1
0
1
1
1
1
LDED word
(Load D&E Direct)
<1> Operation code
Low address
High address
<2> Number of bytes :
4
<3> Number of states :
20 (14)
<4> Function
E ← (word), D ← (word+1)
:
Loads the contents of the memory addressed by the 3rd byte (lower address) and 4th byte (upper address)
into the E register, and loads the contents of the next memory address into the D register.
<5> Flags affected
246
:
SK ← 0, L1 ← 0, L0 ← 0
CHAPTER 14
INSTRUCTION SET
LHLD word
(Load H&L Direct)
<1> Operation code
:
0
1
1
1
0
0
0
0
0
0
1
1
1
1
1
1
Low address
High address
<2> Number of bytes :
4
<3> Number of states :
20 (14)
<4> Function
L ← (word), H ← (word+1)
:
Loads the contents of the memory addressed by the 3rd byte (lower address) and 4th byte (upper address)
into the L register, and loads the contents of the next memory address into the H register.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
:
0
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
LSPD word
(Load SP Direct)
<1> Operation code
Low address
High address
<2> Number of bytes :
4
<3> Number of states :
20 (14)
<4> Function
SPL ← (word), SPH ← (word+1)
:
Loads the contents of the memory addressed by the 3rd byte (lower address) and 4th byte (upper address)
into the low-order 8 bits (SPL) of the stack pointer, and loads the contents of the next memory address into
the high-order 8 bits (SPH).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
247
CHAPTER 14
INSTRUCTION SET
LDEAX rpa3
(Load EA with Memory addressed by Register Pair)
<1> Operation code
:
0
1
0
0
1
0
0
0
1
0
0
0
C3 C2 C1 C0
Data
<2> Number of bytes/states:
The number of bytes and number of states are as shown below, depending on the rpa3 specification.
rpa3
D
H
D++
Number of bytes
2
Number of states
14 (8)
<3> Function
:
H++
D+byte
3
H+A
H+B
2
H+EA
H+byte
3
20 (11)
EAL ← (rpa3), EAH ← (rpa3+1)
Loads the contents of the memory addressed by the register pair rpa3 (DE, HL, DE++, HL++, DE+byte, HL+A,
HL+B, HL+EA, HL+byte) specified by C3C2C1C0 (2 to 5, B to F) into the low-order 8 bits (EAL) of the extended
accumulator, and loads the contents of the memory addressed by rpa3+1 into the high-order 8 bits (EAH).
If DE+byte or HL+byte is specified as rpa3, the memory is addressed by the result of adding the 3rd byte
(Data) of the instruction to the contents of DE/HL.
If HL+A, HL+B, or HL+EA is specified, the memory is addressed by the result of adding the contents of the
register (A, B, EA) to the contents of HL.
<4> Flags affected
248
:
SK ← 0, L1 ← 0, L0 ← 0
CHAPTER 14
INSTRUCTION SET
PUSH rp1
(Push Register Pair on Stack)
<1> Operation code
:
1
<2> Number of bytes :
1
0
1
1
0
Q2 Q1 Q0
<3> Number of states :
13 (4)
<4> Function
(SP–1) ← rp1H, (SP–2) ← rp1L, SP ← SP–2
:
Saves the upper half (V, B, D, H, EAH) of the register pair rp1 (VA, BC, DE, HL) or extended accumulator
specified by Q2Q1Q0 (0 to 4) to the stack memory addressed by (SP–1), and saves the lower half (A, C, E,
L, EAL) to the stack memory addressed by (SP–2).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
PROGRAM START
…
LXI SP, 0E000H
;
INTERRUPT ROUTINE
PUSH V
PUSH B
PUSH D
PUSH H
…
PUSH EA
POP EA
POP H
POP D
POP B
POP V
EI
RETI
Stack
DFF6H
EAL
DFF7H
EAH
DFF8H
L
DFF9H
H
DFFAH
E
DFFBH
D
DFFCH
C
DFFDH
B
DFFEH
A
DFFFH
V











 Stack contents when PUSH EA
 is executed










249
CHAPTER 14
INSTRUCTION SET
POP rp1
(Pop Register Pair off Stack)
<1> Operation code
:
1
<2> Number of bytes :
1
0
1
0
0
Q2 Q1 Q0
<3> Number of states :
10 (4)
<4> Function
rp1L ← (SP), rp1H ← (SP+1), SP ← SP+2
:
Restores the contents of the stack memory addressed by (SP) to the lower half (A, C, E, L, EAL) of the register
pair rp1 (VA, BC, DE, HL) or extended accumulator specified by Q2Q1Q0 (0 to 4), and restores the contents
of the stack memory addressed by (SP+1) to the upper half (V, B, D, H, EAH).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
PUSH B
…
PUSH D
POP D
POP B
As the stack pointer indicates the last stack address saved to, the POP instruction restores items in the
reverse order from that used in the PUSH instruction.
LXI rp2, word
(Load Register Pair with Immediate)
<1> Operation code
:
0
P2
P1
P0
0
1
0
0
Low byte
High byte
<2> Number of bytes :
3
<3> Number of states :
10 (10)
<4> Function
rp2 ← word
:
Loads the 2nd byte into the low-order 8 bits (SPL) of the SP or the lower half (C, E, L, EAL) of the register
pair rp2 (BC, DE, HL) or extended address specified by P2P1P0 (0 to 4), and loads the 3rd byte into the upper
half (SPH, B, D, H, EAH). A stacking effect is produced when HL is specified as the register pair.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 1 (when rp2 = HL)
SK ← 0, L1 ← 0, L0 ← 0 (other cases)
<6> Example
250
:
LXI B, 4000H; Load 40H into B register and 00H into C register.
CHAPTER 14
INSTRUCTION SET
TABLE
(Table pick up)
<1> Operation code
:
0
1
0
0
1
0
0
0
1
0
1
0
1
0
0
0
<2> Number of bytes :
2
<3> Number of states :
17 (8)
<4> Function
C ← (PC+3+A), B ← (PC+3+A+1)
:
Loads the table contents addressed by PC+3+A into the C register, and loads the table contents addressed
by PC+3+A+1 into the B register.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
TB0 : MVI
A, 0 ; A=0
TB1 : MVI
A, 1 ; A=1
TB2 : MVI
SLL
PC
TABLE
PC+2 JB
PC + 3
PC + 4
PC + 5
PC + 6
PC + 7
PC + 8
A, 2 ; A=2
A
; Shift Logical Left Accumulator
; BC ← (TABLE)
; PC ← BC

 A=0


 A=1


 A=2

251
CHAPTER 14
INSTRUCTION SET
14.6.3 8-bit operation instructions (Register)
ADD A, r
(Add Register to A)
<1> Operation code
:
0
1
1
0
0
0
1
1
0
0
0
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
A ← A+r
:
0
0
Adds the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7) to the contents of
the accumulator, and stores the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
ADD A, C; Add A and C registers and store result in A.
:
0
1
1
0
0
0
0
1
0
0
0
R2 R1 R0
ADD r, A
(Add A to Register)
<1> Operation code
<2> Number of bytes :
0
2
<3> Number of states :
8 (8)
<4> Function
r ← r+A
:
0
Adds the contents of the accumulator to the contents of the register r (V, A, B, C, D, E, H, L) specified by
R2R1R0 (0 to 7), and stores the result in the specified register.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
ADD B, A; Add B and A registers and store the result in B.
ADC A, r
(Add Register to A with Carry)
<1> Operation code
:
0
1
1
0
0
0
1
1
0
1
0
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
A ← A+r+CY
:
0
0
Adds the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7) to the contents of
the accumulator including the CY flag, and stores the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
ADC A, E; A ← A+E+CY
252
CHAPTER 14
INSTRUCTION SET
ADC r, A
(Add A to Register with Carry)
<1> Operation code
:
0
1
1
0
0
0
0
1
0
1
0
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
r ← r+A+CY
:
0
0
Adds the contents of the accumulator to the contents of the register r (V, A, B, C, D, E, H, L) specified by
R2R1R0 (0 to 7) including the CY flag, and stores the result in the specified register.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
Add the register pairs HL and DE, and store the result in HL:
A←E
MOV
A, E
;
ADD
L, A
;
L ← L+A
MOV
A, D
;
A←D
ADC
H, A
;
H ← H+A+CY
ADDNC A, r
(Add Register to A. Skip if No Carry)
<1> Operation code
:
<2> Number of bytes :
0
1
1
0
0
0
1
0
1
0
0
R2 R1 R0
0
2
<3> Number of states :
8 (8)
<4> Function
A ← A+r; Skip if no carry.
:
0
Adds the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7), to the contents of
the accumulator, and stores the result in the accumulator. Skips if no carry is generated as a result of the
addition.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
ADDNC A, V; A ← A+V
A skip is performed if no carry is generated as a result of the addition.
253
CHAPTER 14
INSTRUCTION SET
ADDNC r, A
(Add A to Register. Skip if No Carry)
<1> Operation code
:
0
1
1
0
0
0
0
0
1
0
0
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
r ← r+A; Skip if no carry.
:
0
0
Adds the contents of the accumulator to the contents of the register r (V, A, B, C, D, E, H, L) specified by
R2R1R0 (0 to 7), and stores the result in the specified register. Skips if no carry is generated as a result of
the addition.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
Add A to the HL register pair.
ADDNC L, A; L ← L+A, SKIP IF NO CARRY.
H, I; H ← H+1
ADI
If no carry is generated a skip is performed and the addition ends; if a carry is
generated, the carry is added to the upper byte and the addition ends.
SUB A, r
(Subtract Register from A)
<1> Operation code
:
0
1
1
0
0
0
1
1
1
0
0
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
A←A←r
:
0
0
Subtracts the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7) from the contents
of the accumulator, and stores the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
SUB A, B; A ← A–B
254
CHAPTER 14
INSTRUCTION SET
SUB r, A
(Subtract A from Register)
<1> Operation code
:
0
1
1
0
0
0
0
1
1
0
0
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
r ← r–A
:
0
0
Subtracts the contents of the accumulator from the contents of the register r (V, A, B, C, D, E, H, L) specified
by R2R1R0 (0 to 7), and stores the result in the specified register.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
SUB A, A; A ← A–A=0
This operation clears the HC and CY flags and sets the Z flag.
SBB A, r
(Subtract Register from A with Borrow)
<1> Operation code
:
0
1
1
0
0
0
1
1
1
1
0
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
A ← A–r–CY
:
0
0
Subtracts the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7) including the CY
flag from the contents of the accumulator, and stores the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
SBB A, L; A ← A–L–CY
SBB r, A
(Subtract A from Register with Borrow)
<1> Operation code
:
<2> Number of bytes :
0
1
1
0
0
0
0
1
1
1
0
R2 R1 R0
0
2
<3> Number of states :
8 (8)
<4> Function
r ← r–A–CY
:
0
Subtracts the contents of the accumulator including the CY flag from the contents of the register r (V, A,
B, C, D, E, H, L) specified by R2R1R0 (0 to 7), and stores the result in the specified register.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
SBB B, A; B ← B–A–CY
255
CHAPTER 14
INSTRUCTION SET
SUBNB A, r
(Subtract Register from A. Skip if No Borrow)
<1> Operation code
:
0
1
1
0
0
0
0
1
0
1
1
0
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
A ← A–r; Skip if no borrow.
:
0
Subtracts the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7) from the contents
of the accumulator, and stores the result in the accumulator. Skips if no borrow is generated as a result of
the subtraction.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
SUBNB A, D; A ← A–D
A skip is performed if no borrow is generated as a result of the subtraction.
SUBNB r, A
(Subtract A from Register. Skip if No Borrow)
<1> Operation code
:
<2> Number of bytes :
0
1
1
0
0
0
0
0
0
1
1
0
R2 R1 R0
2
<3> Number of states :
8 (8)
<4> Function
r ← r–A; Skip if no borrow.
:
0
Subtracts the contents of the accumulator from the contents of the register r (V, A, B, C, D, E, H, L) specified
by R2R1R0 (0 to 7), and stores the result in the specified register. Skips if no borrow is generated as a result
of the subtraction.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
To subtract A from the HL register pair.
256
SUBNB
L, A; L ← L–A, SKIP IF NO BORROW.
SUI
H, I; H ← H–1
CHAPTER 14
INSTRUCTION SET
ANA A, r
(And Register with A)
<1> Operation code
:
0
1
1
0
0
0
1
0
0
0
1
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
A←A
:
0
0
r
Obtains the logical product of the contents of the accumulator and the contents of the register r (V, A, B,
C, D, E, H, L) specified by R2R1R0 (0 to 7), and stores the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
ANA A, L; A ← A
:
0
1
1
0
0
0
0
0
0
0
1
R2 R1 R0
L
ANA r, A
(And A with Register)
<1> Operation code
<2> Number of bytes :
0
2
<3> Number of states :
8 (8)
<4> Function
r←r
:
0
A
Obtains the logical product of the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0
to 7) and the contents of the accumulator, and stores the result in the specified register.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
ANA H, A; H ← H
:
0
1
1
0
0
0
1
0
0
1
1
R2 R1 R0
A
ORA A, r
(Or Register with A)
<1> Operation code
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
A←A
:
0
0
r
Obtains the logical sum of the contents of the accumulator and the contents of the register r (V, A, B, C,
D, E, H, L) specified by R2R1R0 (0 to 7), and stores the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
ORA A, H; A ← A
H
257
CHAPTER 14
INSTRUCTION SET
ORA r, A
(Or A with Register)
<1> Operation code
:
0
1
1
0
0
0
0
0
0
1
1
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
r←r
:
0
0
A
Obtains the logical sum of the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7),
and the contents of the accumulator, and stores the result in the specified register.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
ORA L, A; L ← L
A
XRA A, r
(Exclusive-Or Register with A)
<1> Operation code
:
<2> Number of bytes :
0
1
1
0
0
0
1
0
0
1
0
R2 R1 R0
0
2
<3> Number of states :
8 (8)
<4> Function
A←A
:
0
r
Obtains the exclusive logical sum of the contents of the accumulator and the contents of the register r (V,
A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7), and stores the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
XRA A, B; A ← A
B
XRA r, A
(Exclusive-Or A with Register)
<1> Operation code
:
0
1
1
0
0
0
0
0
0
1
0
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
r←r
:
0
0
A
Obtains the exclusive logical sum of the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0
(0 to 7) and the contents of the accumulator, and stores the result in the specified register.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
XRA C, A; C ← C
258
A
CHAPTER 14
INSTRUCTION SET
GTA A, r
(Greater Than Register)
<1> Operation code
:
0
1
1
0
0
0
0
1
0
1
0
1
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
A–r–1 ← Skip if no borrow.
:
0
Subtracts the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7) and 1 from the
contents of the accumulator. Skips if no borrow is generated as a result of the subtraction (A > r).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
GTA A, B; A–B–1
A skip is performed if A is greater than B.
GTA r, A
(Greater Than A)
<1> Operation code
:
0
1
1
0
0
0
0
0
0
1
0
1
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
r–A–1 ← Skip if no borrow.
:
0
Subtracts the contents of the accumulator and 1 from the contents of the register r (V, A, B, C, D, E, H, L)
specified by R2R1R0 (0 to 7). Skips if no borrow is generated as a result of the subtraction (r > A).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
GTA B, A; B–A–1
A skip is performed if B is greater than A.
259
CHAPTER 14
INSTRUCTION SET
LTA A, r
(Less Than Register)
<1> Operation code
:
0
1
1
0
0
0
1
0
1
1
1
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
A–r; Skip if borrow.
:
0
0
Subtracts the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7) from the contents
of the accumulator. Skips if a borrow is generated as a result of the subtraction (A < r).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
LTA A, L; A–L
A skip is performed if A is less than the L register.
LTA r, A
(Less Than A)
<1> Operation code
:
0
1
1
0
0
0
0
0
1
1
1
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
r–A; Skip if borrow.
:
0
0
Subtracts the contents of the accumulator from the contents of the register r (V, A, B, C, D, E, H, L) specified
by R2R1R0 (0 to 7). Skips if a borrow is generated as a result of the subtraction (r < A).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
LTA H, A; H–A
A skip is performed if the H register is less than A.
260
CHAPTER 14
INSTRUCTION SET
NEA A, r
(Not Equal Register with A)
<1> Operation code
:
0
1
1
0
0
0
1
1
1
0
1
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
A–r; Skip if no zero.
:
0
0
Subtracts the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7) from the contents
of the accumulator. Skips if the result of the subtraction is not zero (A ≠ r).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
NEA A, B; SKIP IF A ≠ B
If A < B the CY flag is set; if A = B the Z flag is set.
NEA r, A
(Not Equal A with Register)
<1> Operation code
:
0
1
1
0
0
0
0
1
1
0
1
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
r–A; Skip if no zero.
:
0
0
Subtracts the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7), Skips if the result
of the subtraction is not zero (r ≠ A).
<5> Flags affected
:
Z, SK, HC, L1← 0, L0 ← 0, CY
<6> Example
:
NEA C, A; SKIP IF C ≠ A
If C < A the CY flag is set; if C = A the Z flag is set.
EQA A, r
(Equal Register with A)
<1> Operation code
:
0
1
1
0
0
0
1
1
1
1
1
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
A–r; Skip if zero.
:
0
0
Subtracts the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7) from the contents
of the accumulator. Skips if the result of the subtraction is zero (A = r).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
EQA A, D; SKIP IF A = D
261
CHAPTER 14
INSTRUCTION SET
EQA r, A
(Equal A with Register)
<1> Operation code
:
0
1
1
0
0
0
0
1
1
1
1
R2 R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
r–A; Skip if zero.
:
0
0
Subtracts the contents of the accumulator from the contents of the register r (V, A, B, C, D, E, H, L) specified
by R2R1R0 (0 to 7). Skips if the result of the subtraction is zero (r = A).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
EQA E, A; SKIP IF E = A
ONA A, r
(On-Test Register with A)
<1> Operation code
:
<2> Number of bytes :
0
1
1
0
0
0
1
1
0
0
1
R2 R1 R0
0
2
<3> Number of states :
8 (8)
<4> Function
A
:
0
r; Skip if no zero.
Obtains the logical product of the contents of the accumulator and the contents of the register r (V, A, B,
C, D, E, H, L) specified by R2R1R0 (0 to 7). Skips if the logical product is not zero.
<5> Flags affected
:
Z, SK, L1 ← 0, L0 ← 0
OFFA A, r
(Off-Test Register with A)
<1> Operation code
:
<2> Number of bytes :
0
1
1
0
0
0
1
1
0
1
1
R2 R1 R0
0
2
<3> Number of states :
8 (8)
<4> Function
A
:
0
r; Skip if zero.
Obtains the logical product of the contents of the accumulator and the contents of the register r (V, A, B,
C, D, E, H, L) specified by R2R1R0 (0 to 7). Skips if the logical product is zero.
<5> Flags affected
262
:
Z, SK, L1 ← 0, L0 ← 0
CHAPTER 14
INSTRUCTION SET
14.6.4 8-bit operation instructions (Memory)
ADDX rpa
(Add Memory addressed by Register Pair to A)
<1> Operation code
:
0
1
1
1
0
0
1
1
0
0
0
A2 A1 A0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
A ← A + (rpa)
:
0
0
Adds the contents of the memory addressed by the register pair rpa (BC, DE, HL, DE+, HL+ DE–, HL–)
specified by A2A1A0 (1 to 7) to the contents of the accumulator, and stores the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
MOV
A, 4000H
LXI
H, 4200H ; HL ← 4200H
ADDX
H
; A ← (4000H)
; A ← A+(HL)
This example adds together the contents of address 4000H and address 4200H.
ADCX rpa
(Add Memory addressed by Register Pair to A with Carry)
<1> Operation code
:
0
1
1
1
0
0
1
1
0
1
0
A2 A1 A0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
A ← A+(rpa)+CY
:
0
0
Adds the contents of the memory addressed by the register pair rpa (BC, DE, HL, DE+, HL+, DE–, HL–)
specified by A2A1A0 (1 to 7) to the contents of the accumulator including the CY flag, and stores the result
in the accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
ADCX D+; A ← A + (DE) + CY, DE ← DE + 1
This example adds the contents of the memory addressed by the DE register pair to
A and stores the result in A, and then increments DE.
263
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INSTRUCTION SET
ADDNCX rpa
(Add Memory addressed by Register Pair to A. Skip if No Carry)
<1> Operation code
:
0
1
1
1
0
0
0
0
1
0
1
0
0
A2 A1 A0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
A ← A + (rpa); Skip if no carry.
:
Adds the contents of the memory addressed by the register pair rpa (BC, DE, HL, DE+, HL+, DE–, HL–)
specified by A2A1A0 (1 to 7) and the contents of the accumulator, and stores the result in the accumulator.
Skips if no carry is generated as a result of the addition.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
LXI
H, 4200H ; HL ← 4200H
LXI
D, 4000H ; DE ← 4000H
MOV
A, 4100H ; A ← (4100H)
ADDNCX
D+
; A ← A+(DE), DE ← DE+1
STAX
H
; (HL) ← A
JMP
MOTOE
This example adds together the contents of address 4100H and address 4000H, and
stores the result in address 4200H if no carry is generated. If a carry is generated,
the STAX instruction is skipped and the JMP instruction is executed to jump to
MOTOE.
SUBX rpa
(Subtract Memory addressed by Register Pair from A)
<1> Operation code
:
<2> Number of bytes :
0
1
1
1
0
0
1
1
1
0
0
A2 A1 A0
0
2
<3> Number of states :
11 (8)
<4> Function
A ← A–(rpa)
:
0
Subtracts the contents of the memory addressed by the register pair rpa (BC, DE, HL, DE+, HL+, DE–,
HL–) specified by A2A1A0 (1 to 7) from the contents of the accumulator, and stores the result in the
accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
SUBX D; A ← A–(DE)
264
CHAPTER 14
INSTRUCTION SET
SBBX rpa
(Subtract Memory addressed by Register Pair from A)
<1> Operation code
:
0
1
1
1
0
0
1
1
1
1
0
A2 A1 A0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
A ← A–(rpa)–CY
:
0
0
Subtracts the contents of the memory addressed by the register pair rpa (BC, DE, HL, DE+, HL+, DE–,
HL–) specified by A2A1A0 (1 to 7) including the CY flag from the contents of the accumulator, and stores the
result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
SBBX D–; A ← A–(DE)–CY, DE ← DE–1
This example subtracts the contents of the memory addressed by the DE register pair
including the CY flag from A and stores the result in A, and then decrements DE.
SUBNBX rpa
(Subtract Memory addressed by Register Pair from A. Skip if No Borrow)
<1> Operation code
:
0
1
1
1
0
0
0
0
1
0
1
1
0
A2 A1 A0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
A ← A–(rpa); Skip if no borrow.
:
Subtracts the contents of the memory addressed by the register pair rpa (BC, DE, HL, DE+, HL+, DE–,
HL–) specified by A2A1A0 (1 to 7) from the contents of the accumulator, and stores the result in the
accumulator. Skips if no borrow is generated as a result of the subtraction.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
SUBNBX B; A ← A–(BC)
A skip is performed if no borrow is generated as a result of the subtraction.
265
CHAPTER 14
INSTRUCTION SET
ANAX rpa
(And Memory addressed by Register Pair with A)
<1> Operation code
:
0
1
1
1
0
0
1
0
0
0
1
A2 A1 A0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
A←A
:
0
0
(rpa)
Obtains the logical product of the contents of the accumulator and the contents of the memory addressed
by the register pair rpa (BC, DE, HL, DE+, HL+, DE–, HL–) specified by A2A1A0 (1 to 7), and stores the result
in the accumulator.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
ANA H–; A ← A
(HL), HL ← HL–1
This example obtains the logical product of A and the memory contents addressed
by the HL register pair and stores the result in A, and then decrements HL.
ORAX rpa
(Or Memory addressed by Register Pair with A)
<1> Operation code
:
0
1
1
1
0
0
1
0
0
1
1
A2 A1 A0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
A←A
:
0
0
(rpa)
Obtains the logical sum of the contents of the accumulator and the contents of the memory addressed by
the register pair rpa (BC, DE, HL, DE+, HL+, DE–, HL–) specified by A2A1A0 (1 to 7), and stores the result
in the accumulator.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
ORAX D; A ← A
266
(DE)
CHAPTER 14
INSTRUCTION SET
XRAX rpa
(Exclusive-Or Memory addressed by Register Pair with A)
<1> Operation code
:
0
1
1
1
0
0
1
0
0
1
0
A2 A1 A0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
A←A
:
0
0
(rpa)
Obtains the exculsive logical sum of the contents of the accumulator and the contents of the memory
addressed by the register pair rpa (BC, DE, HL, DE+, HL+, DE–, HL–) specified by A2A1A0 (1 to 7), and stores
the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
LXI
H, 4000H ; HL ← 4000H
MVI
A, 0A8H
; A ← A8H
; A←A
XRAX H
SK
Z
; SKIP IF ZERO
; (DE) ← A
STAX D
JMP
(HL)
KORED
Memory
10101000
A8H
10101000
A8H
4000H
A8H
↓
00000000
00H
In this example, since the contents of A and the contents of address 4000H are the
same, the exclusive logical sum is 0, and the Z flag is set. Thus the STAX instruction
is skipped by the following SK Z instruction, and the JMP instruction is executed.
GTAX rpa
(Greater Than Memory addressed by Register Pair)
<1> Operation code
:
0
1
1
1
0
0
0
1
0
1
0
1
A2 A1 A0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
A–(rpa)–1; Skip if no borrow.
:
0
Subtracts the contents of the memory addressed by the register pair rpa (BC, DE, HL, DE+, HL+, DE–,
HL–) specified by A2A1A0 (1 to 7) and 1 from the contents of the accumulator. Skips if no borrow is generated
as a result of the subtraction (A>(rpa)).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
GTAX D; A–(DE)–1
A skip is performed if A is greater than the contents of the memory addressed by the
DE register pair.
267
CHAPTER 14
INSTRUCTION SET
LTAX rpa
(Less Than Memory addressed by Register Pair)
<1> Operation code
:
0
1
1
1
0
0
1
0
1
1
1
A2 A1 A0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
A–(rpa); Skip if borrow.
:
0
0
Subtracts the contents of the memory addressed by the register pair rpa (BC, DE, HL, DE+, HL+, DE–,
HL–) specified by A2A1A0 (1 to 7) from the contents of the accumulator. Skips if a borrow is generated as
a result of the subtraction (A<(rpa)).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
LXI
D, 4000H ; DE ← 4000H
LXI
H, 1100H ; HL ← 4100H
LDAX
D
; A ← (4000H)
LTAX
H
; A – (HL)
LDAX
H
; A – (HL)
JMP
KORED
Memory
4000H
20H
4100H
30H
In this example, since the contents of A (contents of address 4000H = 20H) are less
than the memory contents addressed by the HL register pair (contents of address
4100H = 30H), the LDAX instruction is skipped and the JMP instruction is executed.
The CY, SK and HC flags are set as a result of this subtraction.
NEAX rpa
(Not Equal Memory addressed by Register Pair with A)
<1> Operation code
:
0
1
1
1
0
0
0
1
1
1
0
1
A2 A1 A0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
A ← (rpa); Skip if no zero.
:
0
Subtracts the contents of the memory addressed by the register pair rpa (BC, DE, HL, DE+, HL+, DE–,
HL–) specified by A2A1A0 (1 to 7) from the contents of the accumulator. Skips if the result of the subtraction
is no zero (A≠(rpa)).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
NEAX B; SKIP IF A ≠ (BC)
268
CHAPTER 14
INSTRUCTION SET
EQAX rpa
(Equal Memory addressed by Register Pair with A)
<1> Operation code
:
0
1
1
1
0
0
1
1
1
1
1
A2 A1 A0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
A–(rpa); Skip if zero.
:
0
0
Subtracts the contents of the memory addressed by the register pair rpa (BC, DE, HL, DE+, HL+, DE–,
HL–) specified by A2A1A0 (1 to 7) from the contents of the accumulator. Skips if the result of the subtraction
is zero (A=(rpa)).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
EQAX D; SKIP IF A = (DE)
A skip is performed when the contents of A and the contents of the memory
addressed by the DE register pair are equal.
ONAX rpa
(On-Test Memory addressed by Register Pair with A)
<1> Operation code
:
0
1
1
1
0
0
1
1
0
0
1
A2 A1 A0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
A
:
0
0
(rpa); Skip if no zero.
Obtains the logical product of the contents of the accumulator and the contents of the memory addressed
by the register pair rpa (BC, DE, HL, DE+, HL+, DE–, HL–) specified by A2A1A0 (1 to 7), and skips if the logical
product is not zero.
<5> Flags affected
:
Z, SK, L1 ← 0, L0 ← 0
OFFAX rpa
(Off-Test Memory addressed by Register Pair with A)
<1> Operation code
:
<2> Number of bytes :
0
1
1
1
0
0
1
1
0
1
1
A2 A1 A0
0
2
<3> Number of states :
11 (8)
<4> Function
A
:
0
(rpa); Skip if zero.
Obtains the logical product of the contents of the accumulator and the contents of the memory addressed
by the register pair rpa (BC, DE, HL, DE+, HL+, DE–, HL–) specified by A2A1A0 (1 to 7), and skips if the logical
product is zero.
<5> Flags affected
:
Z, SK, L1 ← 0, L0 ← 0
269
CHAPTER 14
INSTRUCTION SET
14.6.5 Immediate data operation instructions
ADI A, byte
(Add Immediate to A)
<1> Operation code
:
0
1
0
0
0
1
1
0
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
A ← A+byte
:
Adds the immediate data in the 2nd byte to the contents of the accumulator, and stores the result in the
accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
ADI r, byte
(Add Immediate to Register)
<1> Operation code
:
0
1
1
1
0
1
0
0
0
1
0
0
0
R2 R1 R0
Data
<2> Number of bytes :
3
<3> Number of states :
11 (11)
<4> Function
r ← r+byte
:
Adds the immediate data in the 3rd byte to the contents of the register r (V, A, B, C, D, E, H, L) specified
by R2R1R0 (0 to 7), and stores the result in the specified register.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
ADI sr2, byte
(Add Immediate to Special Register)
<1> Operation code
:
0
1
1
0
0
1
0
0
S3
1
0
0
0
S2
S1
S0
Data
<2> Number of bytes :
3
<3> Number of states :
20 (11)
<4> Function
sr2 ← sr2+byte
:
Adds the immediate data in the 3rd byte to the contents of the special register sr2 (PA, PB, PC, PD, PF, MKH,
MKL, ANM, SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D), and stores the result in the specified
special register.
<5> Flags affected
270
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
CHAPTER 14
INSTRUCTION SET
ACI A, byte
(Add Immediate to A with Carry)
<1> Operation code
:
0
1
0
1
0
1
1
0
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
A ← A+byte+CY
:
Adds the immediate data in the 2nd byte to the contents of the accumulator including the CY flag, and stores
the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
ACI r, byte
(Add Immediate to Register with Carry)
<1> Operation code
:
0
1
1
1
0
1
0
0
0
1
0
1
0
R2 R1 R0
Data
<2> Number of bytes :
3
<3> Number of states :
11 (11)
<4> Function
r ← r+byte+CY
:
Adds the immediate data in the 3rd byte to the contents of the register r (V, A, B, C, D, E, H, L) specified
by R2R1R0 (0 to 7) including the CY flag, and stores the result in the specified register.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
ACI sr2, byte
(Add Immediate to Special Register with Carry)
<1> Operation code
:
0
1
1
0
0
1
0
0
S3
1
0
1
0
S2
S1
S0
Data
<2> Number of bytes :
3
<3> Number of states :
20 (11)
<4> Function
sr2 ← sr2+byte+CY
:
Adds the immediate data in the 3rd byte to the contents of the special register sr2 (PA, PB, PC, PD, PF, MKH,
MKL, ANM, SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D), including the CY flag, and stores
the result in the specified special register.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
271
CHAPTER 14
INSTRUCTION SET
ADINC A, byte
(Add Immediate to A. Skip if No Carry)
<1> Operation code
:
0
0
1
0
0
1
1
0
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
A ← A+byte; Skip if no carry.
:
Adds the immediate data in the 2nd byte to the contents of the accumulator, and stores the result in the
accumulator. Skips if no carry is generated as a result of the addition.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
ADINC A, 0A3H; A ← A+0A3H
ADINC r, byte
(Add Immediate to Register. Skip if No Carry)
<1> Operation code
:
0
1
1
1
0
1
0
0
0
0
1
0
0
R2 R1 R0
Data
<2> Number of bytes :
3
<3> Number of states :
11 (11)
<4> Function
r ← r+byte; Skip if no carry.
:
Adds the immediate data in the 3rd byte to the contents of the register r (V, A, B, C, D, E, H, L) specified
by R2R1R0 (0 to 7), and stores the result in the specified register. Skips if no carry is generated as a result
of the addition.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
To add immediate data to the HL register pair:
ADINC L,
IMM ; L ← L+IMM, SKIP IF NO CARRY
H, 01H ; H ← H+1
ADI
ADINC sr2, byte
(Add Immediate with Special Register. Skip if No Carry)
<1> Operation code
:
0
1
1
0
0
1
0
0
S3
0
1
0
0
S2
S1
S0
Data
<2> Number of bytes :
3
<3> Number of states :
20 (11)
<4> Function
sr2 ← sr2+byte; Skip if no carry.
:
Adds the immediate data in the 3rd byte to the contents of the special register sr2 (PA, PB, PC, PD, PF, MKH,
MKL, ANM, SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D), and stores the result in the specified
special register. Skips if no carry is generated as a result of the addition.
<5> Flags affected
272
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
CHAPTER 14
INSTRUCTION SET
SUI A, byte
(Subtract Immediate from A)
<1> Operation code
:
0
1
1
0
0
1
1
0
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
A ← A–byte
:
Subtracts the immediate data in the 2nd byte from the contents of the accumulator, and stores the result
in the accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
SUI r, byte
(Subtract Immediate from Register)
<1> Operation code
:
0
1
1
1
0
1
0
0
0
1
1
0
0
R2 R1 R0
Data
<2> Number of bytes :
3
<3> Number of states :
11 (11)
<4> Function
r ← r–byte
:
Subtracts the immediate data in the 3rd byte from the contents of the register r (V, A, B, C, D, E, H, L) specified
by R2R1R0 (0 to 7), and stores the result in the specified register.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
SUI sr2, byte
(Subtract Immediate from Special Register)
<1> Operation code
:
0
1
1
0
0
1
0
0
S3
1
1
0
0
S2
S1
S0
Data
<2> Number of bytes :
3
<3> Number of states :
20 (11)
<4> Function
sr2 ← sr2–byte
:
Subtracts the immediate data in the 3rd byte from the contents of the special register sr2 (PA, PB, PC, PD,
PF, MKH, MKL, ANM, SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D), and stores the result
in the specified special register.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
273
CHAPTER 14
INSTRUCTION SET
SBI A, byte
(Subtract Immediate from A with Borrow)
<1> Operation code
:
0
1
1
1
0
1
1
0
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
A ← A–byte–CY
:
Subtracts the immediate data in the 2nd byte including the CY flag from the contents of the accumulator,
and stores the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
SBI A, 30H; A ← A–30H–CY
This example subtracts 30H from A including the CY flag.
SBI r, byte
(Subtract Immediate from Register with Borrow)
<1> Operation code
:
0
1
1
1
0
1
0
0
0
1
1
1
0
R2 R1 R0
Data
<2> Number of bytes :
3
<3> Number of states :
11 (11)
<4> Function
r ← r–byte–CY
:
Subtracts the immediate data in the 3rd byte including the CY flag from the contents of the register r (V,
A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7), and stores the result in the specified register.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
SBI sr2, byte
(Subtract Immediate from Special Register with Borrow)
<1> Operation code
:
0
1
1
0
0
1
0
0
S3
1
1
1
0
S2
S1
S0
Data
<2> Number of bytes :
3
<3> Number of states :
20 (11)
<4> Function
sr2 ← sr2–byte–CY
:
Subtracts the immediate data in the 3rd byte including the CY flag from the contents of the special register
sr2 (PA, PB, PC, PD, PF, MKH, MKL, ANM, SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D),
and stores the result in the specified special register.
<5> Flags affected
274
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
CHAPTER 14
INSTRUCTION SET
SUINB A, byte
(Subtract Immediate from A. Skip if No Borrow)
<1> Operation code
:
0
0
1
1
0
1
1
0
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
A ← A–byte; Skip if no borrow.
:
Subtracts the immediate data in the 2nd byte from the contents of the accumulator, and stores the result
in the accumulator. Skips if no borrow is generated as a result of the subtraction.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
SUINB r, byte
(Subtract Immediate from Register. Skip if No Borrow)
<1> Operation code
:
0
1
1
1
0
1
0
0
0
0
1
1
0
R2 R1 R0
Data
<2> Number of bytes :
3
<3> Number of states :
11 (11)
<4> Function
r ← r–byte; Skip if no borrow.
:
Subtracts the immediate data in the 3rd byte from the contents of the register r (V, A, B, C, D, E, H, L) specified
by R2R1R0 (0 to 7), and stores the result in the specified register. Skips if no borrow is generated as a result
of the subtraction.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
To subtract immediate data from the HL register pair:
SUINB L,
SUI
IMM
; L ← L – IMM, SKIP IF NO BORROW.
; H ← H–1
H, 01H
SUINB sr2, byte
(Subtract Immediate from Special Register. Skip if No Borrow)
<1> Operation code
:
0
1
1
0
0
1
0
0
S3
0
1
1
0
S2
S1
S0
Data
<2> Number of bytes :
3
<3> Number of states :
20 (11)
<4> Function
sr2 ← sr2–byte; Skip if no borrow.
:
Subtracts the immediate data in the 3rd byte from the contents of the special register sr2 (PA, PB, PC, PD,
PF, MKH, MKL, ANM, SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D), and stores the result
in the specified special register. Skips if no borrow is generated as a result of the subtraction.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
GENSU EQU 10H
SUINB PA, GENSU; PA ← PA–10H
This example subtracts GENSU defined by EQU from the contents of port A, and
stores the result in port A.
275
CHAPTER 14
INSTRUCTION SET
ANI A, byte
(Add Immediate with A)
<1> Operation code
:
0
0
0
0
0
1
1
1
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
A←A
:
byte
Obtains the logical product of the contents of the accumulator and the contents of the immediate data in
the 2nd byte, and stores the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
ANI r, byte
(And Immediate with Register)
<1> Operation code
:
0
1
1
1
0
1
0
0
0
0
0
0
1
R2 R1 R0
Data
<2> Number of bytes :
3
<3> Number of states :
11 (11)
<4> Function
r←r
:
byte
Obtains the logical product of the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0
to 7) and the immediate data in the 3rd byte, and stores the result in the specified register.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
ANI sr2, byte
(And Immediate with Special Register)
<1> Operation code
:
0
1
1
0
0
1
0
0
S3
0
0
0
1
S2
S1
S0
Data
<2> Number of bytes :
3
<3> Number of states :
20 (11)
<4> Function
sr2 ← sr2
:
byte
Obtains the logical product of the contents of the special register sr2 (PA, PB, PC, PD, PF, MKH, MKL, ANM,
SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D) and the immediate data in the 3rd byte, and
stores the result in the specified special register.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
To reset bit 2 (PB2) of port B:
ANI PB, 0FBH; PB ← PB
276
11111011
CHAPTER 14
INSTRUCTION SET
ORI A, byte
(Or Immediate with A)
<1> Operation code
:
0
0
0
1
0
1
1
1
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
A←A
:
byte
Obtains the logical sum of the contents of the accumulator and the contents of the immediate data in the
2nd byte, and stores the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
ORI r, byte
(Or Immediate with Register)
<1> Operation code
:
0
1
1
1
0
1
0
0
0
0
0
1
1
R2 R1 R0
Data
<2> Number of bytes :
3
<3> Number of states :
11 (11)
<4> Function
r←r
:
byte
Obtains the logical sum of the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0 to 7)
and the immediate data in the 3rd byte, and stores the result in the specified register.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
ORI sr2, byte
(Or Immediate with Special Register)
<1> Operation code
:
0
1
1
0
0
1
0
0
S3
0
0
1
1
S2
S1
S0
Data
<2> Number of bytes :
3
<3> Number of states :
20 (11)
<4> Function
sr2 ← sr2
:
byte
Obtains the logical sum of the contents of the special register sr2 (PA, PB, PC, PD, PF, MKH, MKL, ANM,
SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D) and the immediate data in the 3rd byte, and
stores the result in the specified special register.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
To set bit 1 (PC1) of port C:
ORI PC, 02H; PC ← PC
00000010
277
CHAPTER 14
INSTRUCTION SET
XRI A, byte
(Exclusive-Or Immediate with A)
<1> Operation code
:
0
0
0
1
0
1
1
0
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
A←A
:
byte
Obtains the exclusive logical sum of the contents of the accumulator and the contents of the immediate data
in the 2nd byte, and stores the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
XRI A, 8BH; A ← A
8BH
XRI r, byte
(Exclusive-Or Immediate with Register)
<1> Operation code
:
0
1
1
1
0
1
0
0
0
0
0
1
0
R2 R1 R0
Data
<2> Number of bytes :
3
<3> Number of states :
11 (11)
<4> Function
r←r
:
byte
Obtains the exclusive logical sum of the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0
(0 to 7) and the immediate data in the 3rd byte, and stores the result in the specified register.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
XRI sr2, byte
(Exclusive-Or Immediate with Special Register)
<1> Operation code
:
0
1
1
0
0
1
0
0
S3
0
0
1
0
S2
S1
S0
Data
<2> Number of bytes :
3
<3> Number of states :
20 (11)
<4> Function
sr2 ← sr2
:
byte
Obtains the exclusive logical sum of the contents of the special register sr2, (PA, PB, PC, PD, PF, MKH, MKL,
ANM, SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D) and the immediate data in the 3rd byte,
and stores the result in the specified special register.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
To invert bit 2 (PA2) of port A:
XRI PA, 04H; PA ← PA
278
00000100
CHAPTER 14
INSTRUCTION SET
GTI A, byte
(Greater Than Immediate)
<1> Operation code
:
0
0
1
0
0
1
1
1
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
A–byte–1; Skip if no borrow.
:
Subtracts the immediate data in the 2nd byte and 1 from the contents of the accumulator. Skips if no borrow
is generated as a result of the subtraction (A>byte).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
GTI r, byte
(Greater Than Immediate)
<1> Operation code
:
0
1
1
1
0
1
0
0
0
0
1
0
1
R2 R1 R0
Data
<2> Number of bytes :
3
<3> Number of states :
11 (11)
<4> Function
r–byte–1; Skip if no borrow.
:
Subtracts the immediate data in the 3rd byte and 1 from the contents of the register r (V, A, B, C, D, E, H,
L) specified by R2R1R0 (0 to 7). Skip if no borrow is generated as a result of the subtraction (r>byte).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
GTI sr2, byte
(Greater Than Immediate)
<1> Operation code
:
0
1
1
0
0
1
0
0
S3
0
1
0
1
S2
S1
S0
Data
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
sr2–byte–1; Skip if no borrow.
:
Subtracts the immediate data in the 3rd byte and 1 from the contents of the special register sr2 (PA, PB,
PC, PD, PF, MKH, MKL, ANM, SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D). Skips if no
borrow is generated as a result of the subtraction (sr2>byte).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
279
CHAPTER 14
INSTRUCTION SET
LTI A, byte
(Less Than Immediate)
<1> Operation code
:
0
0
1
1
0
1
1
1
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
A–byte ; Skip if borrow.
:
Subtracts the immediate data in the 2nd byte from the contents of the accumulator. Skips if a borrow is
generated as a result of the subtraction (A<byte).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
:
0
1
1
1
0
1
0
0
1
1
1
R2 R1 R0
LTI r, byte
(Less Than Immediate)
<1> Operation code
0
0
Data
<2> Number of bytes :
3
<3> Number of states :
11 (11)
<4> Function
r–byte; Skip if borrow.
:
Subtracts the immediate data in the 3rd byte from the contents of the register r (V, A, B, C, D, E, H, L) specified
by R2R1R0 (0 to 7). Skips if a borrow is generated as a result of the subtraction (r<byte).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
:
0
1
1
0
0
1
0
0
S3
0
1
1
1
S2
S1
S0
LTI sr2, byte
(Less Than Immediate)
<1> Operation code
Data
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
sr2–byte; Skip if borrow.
:
Subtracts the immediate data in the 3rd byte from the contents of the special register sr2 (PA, PB, PC, PD,
PF, MKH, MKL, ANM, SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D). Skips if a borrow is
generated as a result of the subtraction (sr2<byte).
<5> Flags affected
280
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
CHAPTER 14
INSTRUCTION SET
NEI A, byte
(Not Equal Immediate with A)
<1> Operation code
:
0
1
1
0
0
1
1
1
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
A–byte; Skip if no zero.
:
Subtracts the immediate data in the 2nd byte from the contents of the accumulator. Skips if the result of
the subtraction is not zero (A≠byte).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
NEI r, byte
(Not Equal Immediate with Register)
<1> Operation code
:
0
1
1
1
0
1
0
0
0
1
1
0
1
R2 R1 R0
Data
<2> Number of bytes :
3
<3> Number of states :
11 (11)
<4> Function
r–byte; Skip if no zero.
:
Subtracts the immediate data in the 3rd byte from the contents of the register r (V, A, B, C, D, E, H, L) specified
by R2R1R0 (0 to 7). Skips if the result of the subtraction is not zero (r≠byte).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
NEI sr2, byte
(Not Equal Immediate with Special Register)
<1> Operation code
:
0
1
1
0
0
1
0
0
S3
1
1
0
1
S2
S1
S0
Data
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
sr2–byte; Skip if no zero.
:
Subtracts the immediate data in the 3rd byte from the contents of the special register sr2 (PA, PB, PC, PD,
PF, MKH, MKL, ANM, SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D). Skips if the result of
the subtraction is not zero (sr2≠byte).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
281
CHAPTER 14
INSTRUCTION SET
EQI A, byte
(Equal Immediate with A )
<1> Operation code
:
0
1
1
1
0
1
1
1
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
A–byte; Skip if zero.
:
Subtracts the immediate data in the 2nd byte from the contents of the accumulator. Skips if the result of
the subtraction is zero (A=byte).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
EQI r, byte
(Equal Immediate with Register)
<1> Operation code
:
0
1
1
1
0
1
0
0
0
1
1
1
1
R2 R1 R0
Data
<2> Number of bytes :
3
<3> Number of states :
11 (11)
<4> Function
r–byte; Skip if zero.
:
Subtracts the immediate data in the 3rd byte from the contents of the register r (V, A, B, C, D, E, H, L) specified
by R2R1R0 (0 to 7). Skips if the result of the subtraction is zero (r=byte).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
EQI sr2, byte
(Equal Immediate with Special Register)
<1> Operation code
:
0
1
1
0
0
1
0
0
S3
1
1
1
1
S2
S1
S0
Data
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
sr2–byte; Skip if no zero.
:
Subtracts the immediate data in the 3rd byte from the contents of the special register sr2 (PA, PB, PC, PD,
PF, MKH, MKL, ANM, SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D). Skips if the result of
the subtraction is zero (sr2=byte).
<5> Flags affected
282
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
CHAPTER 14
INSTRUCTION SET
ONI A, byte
(On-Test Immediate with A)
<1> Operation code
:
0
1
0
0
0
1
1
1
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
A
:
byte; Skip if no zero.
Obtains the logical product of the contents of the accumulator and the contents of the immediate data in
the 2nd byte, and skips if the result is not zero.
<5> Flags affected
:
Z, SK, L1 ← 0, L0 ← 0
ONI r, byte
(On-Test Immediate with Register)
<1> Operation code
:
0
1
1
1
0
1
0
0
0
1
0
0
1
R2 R1 R0
Data
<2> Number of bytes :
3
<3> Number of states :
11 (11)
<4> Function
r
:
byte; Skip if no zero.
Obtains the logical product of the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0
to 7) and the immediate data in the 3rd byte, and skips if the result is not zero.
<5> Flags affected
:
Z, SK, L1 ← 0, L0 ← 0
ONI sr2, byte
(On-Test Immediate with Special Register)
<1> Operation code
:
0
1
1
0
0
1
0
0
S3
1
0
0
1
S2
S1
S0
Data
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
sr2
:
byte; Skip if no zero.
Obtains the logical product of the contents of the special register sr2 (PA, PB, PC, PD, PF, MKH, MKL, ANM,
SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D) and the immediate data in the 3rd byte, and
skips if the result is not zero.
<5> Flags affected
:
Z, SK, L1 ← 0, L0 ← 0
<6> Example
:
To test bit 0 (PC0) of port C, and jump to XX if "0" or skip and execute the next
instruction if "1" (on).
ONI PC, 01H: PC
00000001
JMP XX
283
CHAPTER 14
INSTRUCTION SET
OFFI A, byte
(Off-Test Immediate with A)
<1> Operation code
:
0
1
0
1
0
1
1
1
Data
<2> Number of bytes :
2
<3> Number of states :
7 (7)
<4> Function
A
:
byte; Skip if zero.
Obtains the logical product of the contents of the accumulator and the contents of the immediate data in
the 2nd byte, and skips if the result is zero.
<5> Flags affected
:
Z, SK, L1 ← 0, L0 ← 0
OFFI r, byte
(Off-Test Immediate with Register)
<1> Operation code
:
0
1
1
1
0
1
0
0
0
1
0
1
1
R2 R1 R0
Data
<2> Number of bytes :
3
<3> Number of states :
11 (11)
<4> Function
r
:
byte; Skip if zero.
Obtains the logical product of the contents of the register r (V, A, B, C, D, E, H, L) specified by R2R1R0 (0
to 7) and the immediate data in the 3rd byte, and skips if the result is zero.
<5> Flags affected
:
Z, SK, L1 ← 0, L0 ← 0
OFFI sr2, byte
(Off-Test Immediate with Special Register)
<1> Operation code
:
0
1
1
0
0
1
0
0
S3
1
0
1
1
S2
S1
S0
Data
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
sr2
:
byte; Skip if zero.
Obtains the logical product of the contents of the special register sr2 (PA, PB, PC, PD, PF, MKH, MKL, ANM,
SMH, EOM, TMM) specified by S3S2S1S0 (0 to 3, 5 to 9, B, D) and the immediate data in the 3rd byte, and
skips if the result is zero.
<5> Flags affected
284
:
Z, SK, L1 ← 0, L0 ← 0
CHAPTER 14
INSTRUCTION SET
14.6.6 Working register operation instructions
ADDW wa
(Add Working Register to A)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
1
0
0
0
0
0
0
Offset
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
A ← A+(V.wa)
:
Adds the contents of the working register addressed by the V register (high-order 8 bits) and the immediate
data in the 3rd byte (low-order 8 bits) to the contents of the accumulator, and stores the result in the
accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
ADCW wa
(Add Working Register to A with Carry)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
1
0
1
0
0
0
0
Offset
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
A ← A+(V.wa)+CY
:
Adds the contents of the working register addressed by the V register (high-order 8 bits) and the immediate
data in the 3rd byte (low-order 8 bits) to the contents of the accumulator including the CY flag, and stores
the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
ADDNCW wa
(Add Working Register to A. Skip if No Carry)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
0
1
0
0
0
0
0
Offset
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
A ← A+(V.wa); Skip if no carry.
:
Adds the contents of the working register addressed by the V register (high-order 8 bits) and the immediate
data in the 3rd byte (low-order 8 bits) to the contents of the accumulator, and stores the result in the
accumulator. Skips if no carry is generated as a result of the addition.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
285
CHAPTER 14
INSTRUCTION SET
SUBW wa
(Subtract Working Register from A)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
1
1
0
0
0
0
0
Offset
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
A ← A–(V.wa)
:
Subtracts the contents of the working register addressed by the V register (high-order 8 bits) and the
immediate data in the 3rd byte (low-order 8 bits) from the contents of the accumulator, and stores the result
in the accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0 L0 ← 0, CY
SBBW wa
(Subtract Working Register from A with Borrow)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
1
1
1
0
0
0
0
Offset
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
A ← A–(V.wa)–CY
:
Subtracts the contents of the working register addressed by the V register (high-order 8 bits) and the
immediate data in the 3rd byte (low-order 8 bits) including the CY flag from the contents of the accumulator,
and stores the result in the accumulator.
<5> Flags affected
286
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
CHAPTER 14
INSTRUCTION SET
SUBNBW wa
(Subtract Working Register from A. Skip if No Borrow)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
0
1
1
0
0
0
0
Offset
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
A ← A–(V.wa); Skip if no borrow.
:
Subtracts the contents of the working register addressed by the V register (high-order 8 bits) and the
immediate data in the 3rd byte (low-order 8 bits) from the contents of the accumulator, and stores the result
in the accumulator. Skips if no borrow is generated as a result of the subtraction.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
WORK EQU
0E0H
; WORK=E0H
LOCA
EQU
0
; LOCA=00H
MVI
V, WORK ; V ← E0H
; A ← A–(E000H)
SUBNBW LOCA
When this instruction is executed, the upper 8-bit address of the area to be accessed
must be loaded beforehand into the V register which specifies the 256-byte working
register area. Next, the lower 8-bit address is selected by the value of the SUBNBW
instruction operand, and then the processing is performed.
ANAW wa
(And Working Register with A)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
0
0
0
1
0
0
0
Offset
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
A←A
:
(V.wa)
Obtains the logical product of the contents of the accumulator and the contents of the working register
addressed by the V register (high-order 8 bits) and the immediate data in the 3rd byte (low-order 8 bits), and
stores the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L ← 0
287
CHAPTER 14
INSTRUCTION SET
ORAW wa
(Or Working Register with A)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
0
0
1
1
0
0
0
Offset
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
A←A
:
(V.wa)
Obtains the logical sum of the contents of the accumulator and the contents of the working register addressed
by the V register (high-order 8 bits) and the immediate data in the 3rd byte (low-order 8 bits), and stores the
result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
XRAW wa
(Exclusive-Or Working Register with A)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
0
0
1
0
0
0
0
Offset
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
A←A
:
(V.wa)
Obtains the exclusive logical sum of the contents of the accumulator land the contents of the working register
addressed by the V register (high-order 8 bits) and the immediate data in the 3rd byte (low-order 8 bits), and
stores the result in the accumulator.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
GTAW wa
(Greater Than Working Register)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
0
1
0
1
0
0
0
Offset
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
A–(V.wa)–1; Skip if no borrow.
:
Subtracts the contents of the working register addressed by the V register (high-order 8 bits) and the
immediate data in the 3rd byte (low-order 8 bits) and 1 from the contents of the accumulator. Skips if no
borrow is generated as a result of the subtraction (A>(V.wa)).
<5> Flags affected
288
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
CHAPTER 14
INSTRUCTION SET
LTAW wa
(Less Than Working Register)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
0
1
1
1
0
0
0
Offset
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
A–(V.wa); Skip if borrow.
:
Subtracts the contents of the working register addressed by the V register (high-order 8 bits) and the
immediate data in the 3rd byte (low-order 8 bits) from the contents of the accumulator. Skips if a borrow
is generated as a result of the subtraction (A<(V.wa)).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
NEAW wa
(Not Equal Working Register with A)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
1
1
0
1
0
0
0
Offset
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
A–(V.wa); Skip if no zero.
:
Subtracts the contents of the working register addressed by the V register (high-order 8 bits) and the
immediate data in the 3rd byte (low-order 8 bits) from the contents of the accumulator. Skips if the result
of the subtraction is not zero (A≠(V.wa)).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
EQAW wa
(Equal Working Register with A)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
1
1
1
1
0
0
0
Offset
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
A–(V.wa); Skip if zero.
:
Subtracts the contents of the working register addressed by the V register (high-order 8 bits) and the
immediate data in the 3rd byte (low-order 8 bits) from the contents of the accumulator. Skips if the result
of the subtraction is zero (A=(V.wa)).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
289
CHAPTER 14
INSTRUCTION SET
ONAW wa
(On-Test Working Register with A)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
1
0
0
1
0
0
0
Offset
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
A
:
(V.wa); Skip if no zero.
Obtains the logical product of the contents of the accumulator and the contents of the working register
addressed by the V register (high-order 8 bits) and the immediate data in the 3rd byte (low-order 8 bits), and
skips if the result is not zero.
<5> Flags affected
:
Z, SK, L1 ← 0, L0 ← 0
OFFAW wa
(Off-Test Working Register with A)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
1
0
1
1
0
0
0
Offset
<2> Number of bytes :
3
<3> Number of states :
14 (11)
<4> Function
A
:
(V.wa); Skip if zero.
Obtains the logical product of the contents of the accumulator and the contents of the working register
addressed by the V register (high-order 8 bits) and the immediate data in the 3rd byte (low-order 8 bits), and
skips if the result is zero.
<5> Flags affected
:
Z, SK, L1 ← 0, L0 ← 0
ANIW wa, byte
(And Immediate with Working Register)
<1> Operation code
:
0
0
0
0
0
1
0
1
Offset
Data
<2> Number of bytes :
3
<3> Number of states :
19 (10)
<4> Function
(V.wa) ← (V.wa)
:
byte
Obtains the logical product of the contents of the working register addressed by the V register (high-order
8 bits) and the immediate data in the 2nd byte (low-order 8 bits), and the immediate data in the 3rd byte,
and stores the result in the addressed working register.
<5> Flags affected
290
:
Z, SK ← 0, L1 ← 0, L0 ← 0
CHAPTER 14
INSTRUCTION SET
ORIW wa, byte
(Or Immediate with Working Register)
<1> Operation code
:
0
0
0
1
0
1
0
1
Offset
Data
<2> Number of bytes :
3
<3> Number of states :
19 (10)
<4> Function
(V.wa) ← (V.wa)
:
byte
Obtains the logical sum of the contents of the working register addressed by the V register (high-order 8
bits) and the immediate data in the 2nd byte (low-order 8 bits), and the immediate data in the 3rd byte, and
stores the result in the addressed working register.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
GTIW wa, byte
(Greater Than Immediate)
<1> Operation code
:
0
0
1
0
0
1
0
1
Offset
Data
<2> Number of bytes :
3
<3> Number of states :
13 (10)
<4> Function
(V.wa)–byte–1; Skip if no borrow.
:
Subtracts the immediate data in the 3rd byte and 1 from the contents of the working register addressed by
the V register (high-order 8 bits) and the immediate data in the 2nd byte (low-order 8 bits). Skips if no borrow
is generated as a result of the subtraction ((V.wa)>byte).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
LTIW wa, byte
(Less Than Immediate)
<1> Operation code
:
0
0
1
1
0
1
0
1
Offset
Data
<2> Number of bytes :
3
<3> Number of states :
13 (10)
<4> Function
(V.wa)–byte; Skip if borrow.
:
Subtracts the immediate data in the 3rd byte from the contents of the working register addressed by the
V register (high-order 8 bits) and the immediate data in the 2nd byte (low-order 8 bits). Skips if a borrow
is generated as a result of the subtraction ((V.wa)<byte).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
291
CHAPTER 14
INSTRUCTION SET
NEIW wa, byte
(Not Equal Immediate with Working Register)
<1> Operation code
:
0
1
1
0
0
1
0
1
Offset
Data
<2> Number of bytes :
3
<3> Number of states :
13 (10)
<4> Function
(V.wa)–byte; Skip if no zero.
:
Subtracts the immediate data in the 3rd byte from the contents of the working register addressed by the
V register (high-order 8 bits) and the immediate data in the 2nd byte (low-order 8 bits), and skips if the result
of the subtraction is not zero ((V.wa)≠byte).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
EQIW wa, byte
(Equal Immediate with Working Register)
<1> Operation code
:
0
1
1
1
0
1
0
1
Offset
Data
<2> Number of bytes :
3
<3> Number of states :
13 (10)
<4> Function
(V.wa)–byte; Skip if zero.
:
Subtracts the immediate data in the 3rd byte from the contents of the working register addressed by the
V register (high-order 8 bits) and the immediate data in the 2nd byte (low-order 8 bits), and skips if the result
of the subtraction is zero ((V.wa)=byte).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
ONIW wa, byte
(On-Test Immediate with Working Register)
<1> Operation code
:
0
1
0
0
0
1
0
1
Offset
Data
<2> Number of bytes :
3
<3> Number of states :
13 (10)
<4> Function
(V.wa)
:
byte; Skip if no zero.
Obtains the logical product of the contents of the working register addressed by the V register (high-order
8 bits) and the immediate data in the 2nd byte (low-order 8 bits), and the immediate data in the 3rd byte,
and skips if the result is not zero.
<5> Flags affected
292
:
Z, SK, L1 ← 0, L0 ← 0
CHAPTER 14
INSTRUCTION SET
OFFIW wa, byte
(Off-Test Immediate with Working Register)
<1> Operation code
:
0
1
0
1
0
1
0
1
Offset
Data
<2> Number of bytes :
3
<3> Number of states :
13 (10)
<4> Function
(V.wa)
:
byte; Skip if zero.
Obtains the logical product of the contents of the working register addressed by the V register (high-order
8 bits) and the immediate data in the 2nd byte (low-order 8 bits), and the immediate data in the 3rd byte,
and skips if the result is zero.
<5> Flags affected
:
Z, SK, L1 ← 0, L0 ← 0
293
CHAPTER 14
INSTRUCTION SET
14.6.7 16-bit operation instructions
EADD EA, r2
(Add Register to EA)
<1> Operation code
:
0
1
1
1
0
0
0
0
1
0
0
0
0
R1 R0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
EA ← EA+r2
:
0
Adds the contents of the register r2 (A, B, C) specified by R1R0 (1 to 3) to the contents of the low-order 8
bits of the extended accumulator, and stores the result in the extended accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
DADD EA, rp3
(Add Register Pair to EA)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
1
0
0
0
1
P1
P0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
EA ← EA+rp3
:
Adds the contents of the register pair rp3 (BC, DE, HL) specified by P1P0 (1 to 3) to the contents of the
extended accumulator, and stores the result in the extended accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
DADC EA, rp3
(Add Register Pair to EA with Carry)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
1
0
1
0
1
P1
P0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
EA ← EA+rp3+CY
:
Adds the contents of the register pair rp3 (BC, DE, HL) specified by P1P0 (1 to 3) to the contents of the
extended accumulator including the CY flag, and stores the result in the extended accumulator.
<5> Flags affected
294
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
CHAPTER 14
INSTRUCTION SET
DADDNC EA, rp3
(Add Register Pair to EA. Skip if no Carry)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
0
1
0
0
1
P1
P0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
EA ← EA+rp3; Skip if no carry.
:
Adds the contents of the register pair rp3 (BC, DE, HL) specified by P1P0 (1 to 3) to the contents of the
extended accumulator, and stores the result in the extended accumulator. Skips if no carry is generated
as a result of the addition.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
ESUB EA, r2
(Subtract Register from EA)
<1> Operation code
:
<2> Number of bytes :
0
1
1
1
0
0
0
0
1
1
0
0
0
R1 R0
2
<3> Number of states :
11 (8)
<4> Function
EA ← EA–r2
:
0
Subtracts the contents of the register r2 (A, B, C) specified by R1R0 (1 to 3) from the contents of the extended
accumulator, and stores the result in the extended accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
DSUB EA, rp3
(Subtract Register Pair from EA)
<1> Operation code
:
<2> Number of bytes :
0
1
1
1
0
1
0
0
1
1
1
0
0
1
P1
P0
2
<3> Number of states :
11 (8)
<4> Function
EA ← EA–rp3
:
Subtracts the contents of the register pair rp3 (BC, DE, HL) specified by P1P0 (1 to 3) from the contents of
the extended accumulator, and stores the result in the extended accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
295
CHAPTER 14
INSTRUCTION SET
DSBB EA, rp3
(Subtract Register Pair from EA with Borrow)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
1
1
1
0
1
P1
P0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
EA ← EA–rp3–CY
:
Subtracts the contents of the register pair rp3 (BC, DE, HL) specified by P1P0 (1 to 3) including the CY flag
from the contents of the extended accumulator, and stores the result in the extended accumulator.
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
DSUBNB EA, rp3
(Subtract Register Pair from EA. Skip if No Borrow)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
0
1
1
0
1
P1
P0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
EA ← EA–rp3; Skip if no borrow.
:
Subtracts the contents of the register pair rp3 (BC, DE, HL) specified by P1P0 (1 to 3) from the contents of
the extended accumulator, and stores the result in the extended accumulator. Skips if no borrow is generated
as a result of the subtraction.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
DAN EA, rp3
(And Register Pair with EA)
<1> Operation code
:
<2> Number of bytes :
0
1
1
1
0
1
0
0
1
0
0
0
1
1
P1
P0
2
<3> Number of states :
11 (8)
<4> Function
EA ← EA
:
rp3
Obtains the logical product of the contents of the extended accumulator and the contents of the register
pair rp3 (BC, DE, HL) specified by P1P0 (1 to 3), and stores the result in the extended accumulator.
<5> Flags affected
296
:
Z, SK ← 0, L1 ← 0, L0 ← 0
CHAPTER 14
INSTRUCTION SET
DOR EA, rp3
(Or Register Pair with EA)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
0
0
1
1
1
P1
P0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
EA ← EA
:
rp3
Obtains the logical sum of the contents of the extended accumulator and the contents of the register pair
rp3 (BC, DE, HL) specified by P1P0 (1 to 3), and stores the result in the extended accumulator.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
DXR EA, rp3
(Exclusive-Or Register Pair with EA)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
0
0
1
0
1
P1
P0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
EA ← EA
:
rp3
Obtains the exclusive logical sum of the contents of the extended accumulator and the contents of the
register pair rp3 (BC, DE, HL) specified by P1P0 (1 to 3), and stores the result in the extended accumulator.
<5> Flags affected
:
Z, SK ← 0, L1 ← 0, L0 ← 0
DGT EA, rp3
(Greater Than Register Pair)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
0
1
0
1
1
P1
P0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
EA–rp3–1; Skip if no borrow.
:
Subtracts the contents of the register pair rp3 (BC, DE, HL) specified by P1P0 (1 to 3) and 1 from the contents
of the extended accumulator, and skips if no borrow is generated as a result of the subtraction (EA>rp3).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
DGT EA, B; EA–BC–1
A skip is performed if EA is greater than BC.
297
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INSTRUCTION SET
DLT EA, rp3
(Less Than Register Pair)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
0
1
1
1
1
P1
P0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
EA–rp3; Skip if borrow.
:
Subtracts the contents of the register pair rp3 (BC, DE, HL) specified by P1P0 (1 to 3) from the contents of
the extended accumulator, and skips if a borrow is generated as a result of the subtraction (EA<rp3).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
DLT EA, B; EA–BC
A skip is performed if BC is greater than EA.
DNE EA, rp3
(Not Equal Register Pair with EA)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
1
1
0
1
1
P1
P0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
EA–rp3; Skip if no zero.
:
Subtracts the contents of the register pair rp3 (BC, DE, HL) specified by P1P0 (1 to 3) from the contents of
the extended accumulator, and skips if the result of the subtraction is not zero (EA≠rp3).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
DNE EA, B; EA–BC
A skip is performed if EA and BC are not equal.
DEQ EA, rp3
(Equal Register Pair with EA)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
1
1
1
1
1
P1
P0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
EA–rp3; Skip if zero.
:
Subtracts the contents of the register pair rp3 (BC, DE, HL) specified by P1P0 (1 to 3) from the contents of
the extended accumulator, and skips if the result of the subtraction is zero (EA=rp3).
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
DEQ EA, B; EA–BC
A skip is performed if EA and BC are equal.
298
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INSTRUCTION SET
DON EA, rp3
(On-Test Register Pair with EA)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
1
0
0
1
1
P1
P0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
EA
:
rp3; Skip if no zero.
Obtains the logical product of the contents of the extended accumulator and the contents of the register
pair rp3 (BC, DE, HL) specified by P1P0 (1 to 3), and skips if the result is not zero.
<5> Flags affected
:
Z, SK, L1 ← 0, L0 ← 0
DOFF EA, rp3
(Off-Test Register Pair with EA)
<1> Operation code
:
0
1
1
1
0
1
0
0
1
1
0
1
1
1
P1
P0
<2> Number of bytes :
2
<3> Number of states :
11 (8)
<4> Function
EA
:
rp3; Skip if zero.
Obtains the logical product of the contents of the extended accumulator and the contents of the register
pair rp3 (BC, DE, HL) specified by P1P0 (1 to 3), and skips if the result is zero.
<5> Flags affected
:
Z, SK, L1 ← 0, L0 ← 0
299
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INSTRUCTION SET
14.6.8 Multiplication/division instructions
MUL r2
(Multiply A by Register)
<1> Operation code
:
0
1
0
0
1
0
0
0
0
1
0
1
1
R1 R0
<2> Number of bytes :
2
<3> Number of states :
32 (8)
<4> Function
EA ← A × r2
:
0
Performs unsigned multiplication of the contents of the accumulator by the contents of the register r2 (A,
B, C) specified by R1R0 (1 to 3), and stores the result in the extended accumulator.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
:
0
1
0
0
1
0
0
0
0
1
1
1
1
R1 R0
DIV r2
(Divide EA by Register)
<1> Operation code
0
<2> Number of bytes :
2
<3> Number of states :
59 (8)
<4> Function
EA ← EA ÷ r2, r2 ← remainder
:
Divides (unsigned division) the contents of the extended accumulator by the contents of the register r2 (A,
B, C) specified by R1R0 (1 to 3), and stores the quotient in the extended accumulator and the remainder in
register r2. If r2 = 0 (0 divisor), FFFFH is stored in EA and the contents of the low-order 8 bits of EA prior
to execution of the instruction are stored in r2.
<5> Flags affected
300
:
SK ← 0, L1 ← 0, L0 ← 0
CHAPTER 14
INSTRUCTION SET
14.6.9 Increment/decrement instructions
INR r2
(Increment Register)
<1> Operation code
:
0
<2> Number of bytes :
1
1
0
0
0
0
<3> Number of states :
4 (4)
<4> Function
r2 ← r2+1; Skip if carry.
:
R1 R0
Increments the contents of the register r2 (A, B, C) specified by R1R0 (1 to 3), and skips if a carry is generated
as a result of the increment.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0
<6> Example
:
INR A; A ← A+1
INRW wa
(Increment Working Register)
<1> Operation code
:
0
0
1
0
0
0
0
0
Offset
<2> Number of bytes :
2
<3> Number of states :
16 (7)
<4> Function
(V.wa) ← (V.wa)+1; Skip if carry.
:
Increments the contents of the working register addressed by the V register (high-order 8 bits) and the
immediate data in the 2nd byte (low-order 8 bits), and skips if a carry is generated as a result of the increment.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0
<6> Example
:
MVI V, 0FFH
INRW 0FFH ;
(FFFFH) ← (FFFFH)+1
This example increments the contents of the working register in address FFFFH.
INX rp
(Increment Register Pair)
<1> Operation code
:
0
<2> Number of bytes :
1
<3> Number of states :
7 (4)
<4> Function
rp ← rp+1
:
0
P1
P0
0
0
1
0
Increments SP or the contents of the register pair rp (BC, DE, HL) specified by P1P0 (0 to 3).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
INX D; DE ← DE+1
In this example the 16-bit register with D as the high-order 8 bits and E as the loworder 8 bits is incremented.
301
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INSTRUCTION SET
INX EA
(Increment EA)
<1> Operation code
:
1
<2> Number of bytes :
1
0
1
0
<3> Number of states :
7 (4)
<4> Function
EA ← EA+1
:
1
0
0
0
Increments the extended accumulator.
:
SK ← 0, L1 ← 0, L0 ← 0
:
0
<2> Number of bytes :
1
<5> Flags affected
DCR r2
(Decrement Register)
<1> Operation code
1
0
1
0
0
R1 R0
<3> Number of states :
4 (4)
<4> Function
r2 ← r2–1; Skip if borrow.
:
Decrements the contents of the register r2 (A, B, C) specified by R1R0 (1 to 3), and skips if a borrow is
generated as a result of the decrement.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0
<6> Example
:
DCR B; B ← B–1
DCRW wa
(Decrement Working Register)
<1> Operation code
:
0
0
1
1
0
0
0
0
Offset
<2> Number of bytes :
2
<3> Number of states :
16 (7)
<4> Function
(V.wa) ← (V.wa)–1; Skip if borrow.
:
Decrements the contents of the working register addressed by the V register (high-order 8 bits) and the
immediate data in the 2nd byte (low-order 8 bits), and skips if a borrow is generated as a result of the
decrement.
<5> Flags affected
:
Z, SK, HC, L1 ← 0, L0 ← 0
<6> Example
:
MVI
V, 50H
DCRW
0
; (5000H) ← (5000H)–1
This example decrements the contents of the working register in address 5000H.
302
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INSTRUCTION SET
DCX rp
(Decrement Register Pair)
<1> Operation code
:
0
<2> Number of bytes :
1
0
P1
<3> Number of states :
7 (4)
<4> Function
rp ← rp–1
:
P0
0
0
1
1
Decrements SP or the contents of the register pair rp (BC, DE, HL) specified by P1P0 (0 to 3).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
DCX H; HL ← HL–1
:
1
<2> Number of bytes :
1
<3> Number of states :
7 (4)
<4> Function
EA ← EA–1
DCX EA
(Decrement EA)
<1> Operation code
:
0
1
0
1
0
0
1
Decrements the extended accumulator.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
303
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INSTRUCTION SET
14.6.10 Other operation instructions
DAA
(Decimal Adjust A)
<1> Operation code
:
0
<2> Number of bytes :
1
<3> Number of states :
4 (4)
<4> Function
1
1
0
0
0
0
1
:
Determines the contents of the accumulator, CY flag and HC flag, and performs decimal adjustment as shown
below. This instruction is only meaningful after execution of an operation between decimal (BCD) data items.
Condition
Operation
A3-0 ≤ 9
A7-4 ≤ 9 and CY = 0
A←A
HC = 0
A7-4 ≥ 10 or CY = 1
A ← A + 01100000
A3-0 ≥ 10
A7-4 < 9 and CY = 0
A ← A + 00000110
A7-4 ≥ 9 or CY = 1
A ← A + 01100110
A7-4 ≤ 9 and CY = 0
A ← A + 00000110
A7-4 ≥ 10 or CY = 1
A ← A + 01100110
HC = 0
HC=1
<5> Flags affected
:
Z, SK ← 0, HC, L1 ← 0, L0 ← 0, CY
<6> Example
:
MVI
A,
88H
ADI
A,
79H ; A=01H, CY=1, HC=1
; A ← A+66H, A=67H, CY=1
DAA
; 88+79=167
ADI
DAA
<7> Caution
:
10001000 88H
+ 01111001 79H
00000001 01H
Carry HC
+ 01100110 66H
01100111 67H
This instruction cannot be used for adjustment after execution of a subtract instruction.
When decimal (BCD) data subtraction is performed, a complement instruction should
be used.
304
CHAPTER 14
INSTRUCTION SET
STC
(Set Carry)
<1> Operation code
:
0
1
0
0
1
0
0
0
0
0
1
0
1
0
1
1
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
CY ← 1
:
Sets (1) the CY flag.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0, CY ← 1
:
0
1
0
0
1
0
0
0
0
0
1
0
1
0
1
0
CLC
(Clear Carry)
<1> Operation code
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
CY ← 0
:
Sets (0) the CY flag.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0, CY ← 0
:
0
1
0
0
1
0
0
0
0
0
1
1
1
0
1
0
NEGA
(Negate A)
<1> Operation code
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
A ← A+1
:
Obtains the two's complement of the accumulator contents.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
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INSTRUCTION SET
14.6.11 Rotation/shift instructions
RLD
(Rotate Left Digit)
<1> Operation code
:
0
1
0
0
1
0
0
0
0
0
1
1
1
0
0
0
<2> Number of bytes :
2
<3> Number of states :
17 (8)
<4> Function
A3-0 ← (HL)7-4, (HL)7-4 ← (HL)3-0, (HL)3-0 ← A3-0
:
7
4 3
Unchanged
A
7
0
4 3
0
(HL)
Performs left rotation as 4-bit (digit) units of the low-order 4 bits of the accumulator and the high-order 4
bits and low-order 4 bits of the memory addressed by the HL register pair. Bits 7 to 4 of the accumulator
are not affected.
<5> Flags affected
:
<6> Example
:
SK ← 0, L1 ← 0, L0 ← 0
A
7
306
4 3
(HL)
0
7
4 3
0
Before execution
0 0 0 0 0 0 0 1
0 1 0 1 0 0 1 1
7
7
After execution
0 0 0 0 0 1 0 1
4 3
0
4 3
0
0 0 1 1 0 0 0 1
CHAPTER 14
INSTRUCTION SET
RRD
(Rotate Right Digit)
<1> Operation code
:
0
1
0
0
1
0
0
0
0
0
1
1
1
0
0
1
<2> Number of bytes :
2
<3> Number of states :
17 (8)
<4> Function
(HL)7-4 ← A3-0, (HL)3-0 ← (HL)7-4, A3-0 ← (HL)3-0
:
7
A
4 3
Unchanged
7
0
4 3
0
(HL)
Performs right rotation as 4-bit (digit) units of the low-order 4 bits of the accumulator and the high-order 4
bits and low-order 4 bits of the memory addressed by the HL register pair. Bits 7 to 4 of the accumulator
are not affected.
<5> Flags affected
:
<6> Example
:
SK ← 0, L1 ← 0, L0 ← 0
A
7
Before execution
After execution
(HL)
4 3
7
0
4 3
0
0 0 0 0 0 0 0 1
0 1 0 1 0 0 1 1
7
7
4 3
0
0 0 0 0 0 0 1 1
4 3
0
0 0 0 1 0 1 0 1
RLL r2
(Rotate Logical Left Register)
<1> Operation code
:
0
1
0
0
1
0
0
0
0
0
1
1
0
1
R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
r2m+1 ← r2m, r20 ← CY, CY ← r27
:
7
CY
0
r2
Performs 1-bit left rotation including the CY flag of the contents of the register r2 (A, B, C) specified by R1R0
(1 to 3).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0, CY
307
CHAPTER 14
INSTRUCTION SET
RLR r2
(Rotate Logical Right Register)
<1> Operation code
:
0
1
0
0
1
0
0
0
0
0
1
1
0
0
R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
r2m–1 ← r2m, r27 ← CY, CY ← r20
:
7
0
CY
r2
Performs 1-bit right rotation including the CY flag of the contents of the register r2 (A, B, C) specified by R1R0
(1 to 3).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0, CY
SLL r2
(Shift Logical Left Register)
<1> Operation code
:
<2> Number of bytes :
0
1
0
0
1
0
0
0
0
0
1
0
0
1
R1 R0
2
<3> Number of states :
8 (8)
<4> Function
r2m+1 ← r2m, r20 ← 0, CY ← r27
:
7
CY
0
0
r2
Performs a 1-bit left shift of the contents of the register r2 (A, B, C) specified by R1R0 (1 to 3). r27 is shifted
into the CY flag, and 0 is loaded into r20.
<5> Flags affected
308
:
SK ← 0, L1 ← 0, L0 ← 0, CY
CHAPTER 14
INSTRUCTION SET
SLR r2
(Shift Logical Right Register)
<1> Operation code
:
0
1
0
0
1
0
0
0
0
0
1
0
0
0
R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
r2m–1 ← r2m, r27 ← 0, CY ← r20
:
7
0
0
r2
CY
Performs a 1-bit right shift of the contents of the register r2 (A, B, C) specified by R1R0 (1 to 3). r20 is shifted
into the CY flag, and 0 is loaded into r27.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0, CY
SLLC r2
(Shift Logical Left Register. Skip if Carry)
<1> Operation code
:
0
1
0
0
1
0
0
0
0
0
0
0
0
1
R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
r2m+1 ← r2m, r20 ← 0, CY ← r27; Skip if carry.
:
7
CY
0
0
r2
Performs a 1-bit left shift of the contents of the register r2 (A, B, C) specified by R1R0 (1 to 3). r27 is shifted
into the CY flag, and 0 is loaded into r20. Skips if a carry is generated as a result of the shift.
<5> Flags affected
:
SK, L1 ← 0, L0 ← 0, CY
309
CHAPTER 14
INSTRUCTION SET
SLRC r2
(Shift Logical Right Register. Skip if Carry)
<1> Operation code
:
0
1
0
0
1
0
0
0
0
0
0
0
0
0
R1 R0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
r2m–1 ← r2m, r27 ← 0, CY ← r20
:
7
0
0
r2
CY
Performs a 1-bit right shift of the contents of the register r2 (A, B, C) specified by R1R0 (1 to 3). r20 is shifted
into the CY flag, and 0 is loaded into r27. Skips if a carry is generated as a result of the shift.
<5> Flags affected
:
SK, L1 ← 0, L0 ← 0, CY
:
0
1
0
0
1
0
0
0
1
0
1
1
0
1
0
0
DRLL EA
(Rotate Logical Left EA)
<1> Operation code
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
EAn+1 ← EAn, EA0 ← CY, CY ← EA15
:
15
CY
0
EA
Performs 1-bit left rotation including the CY flag of the contents of the extended accumulator.
<5> Flags affected
310
:
SK ← 0, L1 ← 0, L0 ← 0, CY
CHAPTER 14
INSTRUCTION SET
DRLR EA
(Rotate Logical Right EA)
<1> Operation code
:
0
1
0
0
1
0
0
0
1
0
1
1
0
0
0
0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
EAn–1 ← EAn, EA15 ← CY, CY ← EA0
:
15
0
CY
EA
Performs 1-bit right rotation including the CY flag of the contents of the extended accumulator.
<5> Flags affected
:
SK← 0, L1 ← 0, L0 ← 0, CY
:
0
1
0
0
1
0
0
0
1
0
1
0
0
1
0
0
DSLL EA
(Shift Logical Left EA)
<1> Operation code
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
EAn+1 ← EAn, EA0 ← 0, CY ← EA15
:
15
0
0
CY
EA
Performs a 1-bit left shift of the contents of the extended accumulator. EA15 is shifted into the CY flag, and
0 is loaded into EA0.
<5> Flags affected
:
SK← 0, L1 ← 0, L0 ← 0, CY
311
CHAPTER 14
INSTRUCTION SET
DSLR EA
(Shift Logical Right EA)
<1> Operation code
:
0
1
0
0
1
0
0
0
1
0
1
0
0
0
0
0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
EAn–1 ← EAn, EA15 ← 0, CY ← EA0
:
15
0
0
CY
EA
Performs a 1-bit right shift of the contents of the extended accumulator. EA0 is shifted into the CY flag, and
0 is loaded into EA15.
<5> Flags affected
312
:
SK← 0, L1 ← 0, L0 ← 0, CY
CHAPTER 14
INSTRUCTION SET
14.6.12 Jump instructions
JMP word
(Jump direct)
<1> Operation code
:
0
1
0
1
0
1
0
0
Low address
High address
<2> Number of bytes :
3
<3> Number of states :
10 (10)
<4> Function
PC ← word
:
Loads the immediate data in the 2nd byte into the low-order 8 bits (PC7–0) of the program counter, loads the
immediate data in the 3rd byte into the high-order 8 bits (PC15-8), and jumps to the address indicated by the
immediate data.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
MVI
C, 7FH
LXI
H, 4000H ; HL=4000H
LXI
D, 5000H ; DE=5000H
; C=127
; (DE)+ ← (HL)+, C ← C–1
BLOCK
JMP
; PC ← OWARI
OWARI
; JUMP TO OWARI
When the 128-byte block transfer is completed, the program jumps to the address
indicated by the label OWARI.
JB
(Jump BC indirect)
<1> Operation code
:
0
<2> Number of bytes :
1
0
1
0
0
0
<3> Number of states :
4 (4)
<4> Function
PC15-8 ← B, PC7–0 ← C
:
0
1
Loads the contents of the B register into the high-order 8 bits (PC15-8) of the program counter, loads the
contents of the C register into the low-order 8 bits (PC7–0), and jumps to the address indicated by the BC
register pair.
An effective method is, for example, to jump using the JB instruction after loading address information into
BC by means of the TABLE instruction.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
313
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INSTRUCTION SET
JR word
(Jump Relative)
<1> Operation code
:
1
<2> Number of bytes :
1
1
jdisp1
<3> Number of states :
10 (4)
<4> Function
PC ← PC+1+jdisp1
:
Jumps to the address obtained by adding the 6-bit displacement value jdisp1 to the start address of the next
instruction. jdisp1 is handled as signed two's complement data (–32 to +31), with bit 5 as the sign bit.
15
0
PC + 1
+
15
6 5 4
0
S









X
…
jdisp1
15
0
…
Jump address
When S = 0: X = All 0's
When S = 1: X = All 1's
A jump destination address or label which takes account of the jump range should be directly written as the
operand of the JR instruction. Thus, when a JR instruction is executed at address 1000, for example, the
possible jump range is from address 969 to address 1032.
:
<6> Example
:
SK ← 0, L1 ← 0, L0 ← 0
CLWR : LXI
…
<5> Flags affected
D, 2000H ; DE=2000H
MVI
C, 7
; C=7, LOOP COUNTER
XRA
A, A
; CLEAR A
98 LOOP : STAX D+
; (DE) ← 0, DE ← DE+1
99
…
100
DCR
C
; C ← C–1, SKIP IF BORROW
JR
LOOP
; JUMP TO LOOP
RET
;
The loop is executed repeatedly by means of the JR instruction until the 8 addresses
starting at memory address 2000H (i.e. addresses up to the including address 2007H)
have been cleared.
Since the displacement value is this case is –3, the actual operation code is as follows:
1
1
1
1
1
1
0
1
Two's complement of –3
314
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INSTRUCTION SET
JRE word
(Jump Relative Extended)
<1> Operation code
:
0
1
0
0
1
1
1
jH
jdispL
<2> Number of bytes :
2
<3> Number of states :
10 (7)
<4> Function
PC ← PC+2+jdisp
:
15
0
PC + 2
+
15
9 8 7
0
S













X
jdisp
15
0
Jump address
When S = 0: X = All 0's
When S = 1: X = All 1's
Jumps to the address obtained by adding the 9-bit displacement value jdisp to the start address of the next
instruction. jdisp is handled as signed two's complement data (–256 to +255), with bit 8 (bit 0 of the 1st
byte) as the sign bit.
A jump destination address or label which takes account of the jump range should be directly written as the
operand of the JRE instruction. Thus, when a JRE instruction is executed at address 1000, for example,
the possible jump range is from address 746 to address 1257.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
:
0
1
0
0
1
0
0
0
0
0
1
0
1
0
0
0
JEA
(Jump EA indirect)
<1> Operation code
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
PC ← EA
:
Loads the contents of the high-order 8 bits (EAH) of the extended accumulator into the high-order 8 bits
(PC15-8) of the program, counter, loads the low-order 8 bits (EAL) of the extended accumulator into the loworder 8 bits (PC7-0), and jumps to the address indicated by the extended accumulator.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
315
CHAPTER 14
INSTRUCTION SET
14.6.13 Call instructions
CALL word
(Call subroutine direct)
<1> Operation code
:
0
1
0
0
0
0
0
0
Low address
High address
<2> Number of bytes :
3
<3> Number of states :
16 (10)
<4> Function
(SP–1) ← PC+315-8, (SP–2) ← PC+37-0,
:
SP ← SP–2, PC ← word
Stores the high-order 8 bits of the start address of the next instruction in the stack memory indicated by SP–
1 and stores the low-order 8 bits in the stack memory indicated by SP–2, then loads the immediate data in
the 2nd byte into the low-order 8 bits (PC7-0) of the program counter and loads the immediate data in the
3rd byte into the high-order 8 bits (PC15–8), and jumps to the address indicated by the immediate data.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
CALB
(Call subroutine BC indirect)
<1> Operation code
:
0
1
0
0
1
0
0
0
0
0
1
0
1
0
0
1
<2> Number of bytes :
2
<3> Number of states :
17 (8)
<4> Function
(SP–1) ← PC+215–8, (SP–2) ← PC+27–0,
:
SP ← PC–2, PC15–8 ← B, PC7–0 ← C
Stores the high-order 8 bits of the start address of the next instruction in the stack memory indicated by SP–
1 and stores the low-order 8 bits in the stack memory indicated by SP–2, then loads the B register into the
high-order 8 bits (PC15-8) of the program counter and loads the contents of the C register into the low-order
8 bits (PC7–0), and jumps to the address indicated by the BC register.
<5> Flags affected
316
:
SK ← 0, L1 ← 0, L0 ← 0
CHAPTER 14
INSTRUCTION SET
CALF word
(Call Subroutine in Fixed Area)
<1> Operation code
:
0
1
1
1
1
faH
faL
<2> Number of bytes :
2
<3> Number of states :
13 (7)
<4> Function
(SP–1) ← PC+215–8, (SP–2) ← PC+27–0,
:
SP ← SP–2, PC15–11 ← 00001, PC10–0 ← fa
Stores the high-order 8 bits of the start address of the next instruction in the stack memory indicated by SP–
1 and stores the low-order 8 bits in the stack memory indicated by SP–2, then loads 00001 into the highorder 5 bits (PC15-11) of the program counter and loads the 11-bit immediate data fa into the low-order 11
bits (PC10-0), and jumps to the address indicated by the immediate data.
A label or number from 800H to FFFH (2K-byte range) should be directly as the operand of the CALF
instruction.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
:
1
CALT word
(Call Table Address)
<1> Operation code
0
0
ta
<2> Number of bytes :
1
<3> Number of states :
16 (4)
<4> Function
(SP–1) ← PC+115–8, (SP–2) ← PC+17–0,
:
SP ← SP–2, PC7–0 ← (128+2ta), PC15–8 ← (129+2ta)
15
8 7 6 5
0 0 0 0 0 0 0 0 1 0
Effective address
Low address
Effective address + 1
High address
15
1 0
ta
0
= Effective address
Memory (Jump address table)
8 7
0
PC
Stores the high-order 8 bits of the start address of the next instruction in the stack memory indicated by SP–
1 and stores the low-order 8 bits in the stack memory indicated by SP–2, then loads the contents of the
memory addressed by the effective address comprising the 5-bit immediate data ta into the low-order 8 bits
(PC7–0) of the program counter and loads the contents of the memory addressed by the effective address
+1 into the high-order 8 bits (PC15–8), and jumps to the address indicated by the memory contents. The jump
address table must be located in memory address 128 to 191.
The table address should be directly written as a label or a number of up to 16 bits in the operand field of
the CALT instruction.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
317
CHAPTER 14
INSTRUCTION SET
SOFTI
(Software Interrupt)
<1> Operation code
:
0
<2> Number of bytes :
1
1
1
1
0
0
1
0
<3> Number of states :
16
<4> Function
(SP–1) ← PSW, (SP–2) ← PC+115–8,
:
(SP–3) ← PC+17–0, SP ← SP–3,
PC ← 0060H
This is the software interrupt instruction which stores the PSW contents (Z, SK, HC, L1, L0 CY) in the stack
memory indicated by SP–1, then stores the high-order 8 bits of the start address of the next instruction in
the stack memory addressed by SP–2, and stores the low-order 8 bits in the stack memory addressed by
SP–3. The instruction then loads the 0060H into the program counter and jumps to address 0060H.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
<6> Example
:
When a SOFTI instruction is executed at address 500.
500 SOFTI
501
502
Memory
7
0
SP–3
SP–2
SP–1
0 Z SK HC L1 L0 0 CY
500=01F4H
<7> NOTE
:
The following functional difference between the µCOM-87 and 87AD series should
be noted: The µCOM-87 SOFTI instruction saves the address of the SOFTI instruction
itself to the stack memory, whereas the address saved to the stack memory by the
87AD series SOFTI instruction is the start address of the next instruction.
Even if the skip condition is satisfied by execution of the instruction (arithmetic or
logical operation, increment/decrement, skip or RETS instruction) immediately preceding
the SOFTI instruction, the SOFTI is executed, not skipped (see 9.4 Maskable Interrupt
Operation).
318
CHAPTER 14
INSTRUCTION SET
14.6.14 Return instructions
RET
(Return from Subroutine)
<1> Operation code
:
1
<2> Number of bytes :
1
0
1
1
1
0
0
0
<3> Number of states :
10 (4)
<4> Function
PC7–0 ← (SP), PC15–8, ← (SP+1), SP ← SP+2
:
Restores the contents of the stack memory addressed by the SP to the low-order 8 bits (PC7–0) of the program
counter, and restores the contents of the stack memory addressed by SP+1 to the high-order 8 bits (PC15–
8).
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
RETS
(Return from Subroutine and Skip)
<1> Operation code
:
1
<2> Number of bytes :
1
0
1
1
1
0
0
1
<3> Number of states :
10 (4)
<4> Function
PC7–0 ← (SP), PC15–8, ← (SP+1), SP ← SP+2,
:
PC ← PC+n'
n': Number of bytes in the skipped instruction
Restores the contents of the stack memory addressed by the SP to the low-order 8 bits (PC7–0) of the program
counter and restores the contents of the stack memory addressed by SP+1 to the high-order 8 bits (PC15–
then skips unconditionally.
<6> Example
:
SK ← 1, L1 ← 0, L0 ← 0
EQU
0600H
0500
EXAM
CALL
EXAM ; STACK ← 0503H
0503
JMP
0700H
0506
JMP
0800H
0509
0600 EXAM : PUSH
V
PUSH
B
………
:
………
8),
<5> Flags affected
POP
B
POP
V
RETS
; PC ← (STACK), PC ← PC+3
After returning from the subroutine EXAM, JMP 0700H is skipped and JMP 0800H
is executed.
319
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INSTRUCTION SET
RETI
(Return from Interrupt)
<1> Operation code
:
0
<2> Number of bytes :
1
1
1
0
0
0
1
0
<3> Number of states :
13 (4)
<4> Function
PC7–0 ← (SP), PC15–8, ← (SP+1), PSW ← (SP+2), SP ← SP+3
:
Restores the contents of the stack memory addressed by the SP to the low-order 8 bits (PC7–0) of the program
counter, restores the contents of the stack memory addressed by SP+1 to the high-order 8 bits (PC15–8) of
the program counter, and restores the contents of the stack memory addressed by SP+2 to the PSW.
This instruction is used to return from the interrupt service routine for an external interrupt (NMI, INT1, INT2),
an internal interrupt (timer, serial transfer, etc.), or a SOFTI instruction interrupt.
<5> Flags affected
320
:
SK, L1, L0
CHAPTER 14
INSTRUCTION SET
14.6.15 Skip instructions
BIT bit, wa
(Bit Test Working Register)
<1> Operation code
:
0
1
0
1
1
B2 B1 B0
Offset
<2> Number of bytes :
2
<3> Number of states :
10 (7)
<4> Function
Skip if bit on.
:
Skips if the bit specified by B2B1B0 (0 to 7) of the working register addressed by the V register (high-order
8 bits) and the immediate data in the 2nd byte (low-order 8 bits) is 1.
<5> Flags affected
:
SK, L1 ← 0, L0 ← 0
<6> Example
:
When the contents of address 10F0H are 5AH
MVI
V, 40H
BIT
3, 0F0H
JR
$+2
RET
Working register
7 6 5 4 3 2 1 0
40F0H
0 1 0 1 1 0 1 0
In this example, since the specified bit of the specified address is 1, the JR instruction
is skipped and the RET instruction is performed.
SK f
(Skip if Flag)
<1> Operation code
:
0
1
0
0
1
0
0
0
0
0
0
0
1
F2
F1
F0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
Skip if f=1.
:
Skips if flag f (CY, HC, Z) specified by F2F1F0 (2 to 4) is set to 1.
<5> Flags affected
:
SK, L1 ← 0, L0 ← 0
321
CHAPTER 14
INSTRUCTION SET
SKN f
(Skip if No Flag)
<1> Operation code
:
0
1
0
0
1
0
0
0
0
0
0
1
1
F2
F1
F0
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
Skip if f=0.
:
Skips if flag f (CY, HC, Z) specified by F2F1F0 (2 to 4) is set to 0.
<5> Flags affected
:
SK, L1 ← 0, L0 ← 0
:
0
1
0
0
1
0
0
0
0
1
0
I4
I3
I2
I1
I0
SKIT irf
(Skip if Interrupt)
<1> Operation code
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
Skip if irf=1, then reset irf.
:
Skips if the interrupt request flag or test flag (NMI, FT0, FT1, F1, F2, FE0, FE1, FEIN, FAD, FSR, FST, ER,
OV, AN4, AN5, AN6, AN7, SB) specified by I4I3I2I1I0 (0 to C, 10 to 14) is set to 1, then resets the checked
interrupt request flag. The NMI flag is not affected.
<5> Flags affected
:
SK, L1 ← 0, L0 ← 0
:
0
1
0
0
1
0
0
0
0
1
1
I4
I3
I2
I1
I0
SKNIT irf
(Skip if No Interrupt)
<1> Operation code
<2> Number of bytes :
2
<3> Number of states :
8 (8)
<4> Function
Skip if irf=0.
:
Skips if the interrupt request flag or test flag (NMI, FT0, FT1, F1, F2, FE0, FE1, FEIN, FAD, FSR, FST, ER,
OV, AN4, AN5, AN6, AN7, SB) specified by I4I3I2I1I0 (0 to C, 10 to 14) is set to 0.
If the checked interrupt request flag is 1, that interrupt request flag is reset. The NMI flag is not affected.
<5> Flags affected
322
:
SK, L1 ← 0, L0 ← 0
CHAPTER 14
INSTRUCTION SET
14.6.16 CPU control instructions
NOP
(No Operation)
<1> Operation code
:
0
<2> Number of bytes :
1
<3> Number of states :
4 (4)
<4> Function
0
0
0
0
0
0
0
:
Expends 4 states without performing any operation.
:
SK ← 0, L1 ← 0, L0 ← 0
:
1
<2> Number of bytes :
1
<3> Number of states :
4 (4)
<5> Flags affected
EI
(Enable Interrupt)
<1> Operation code
<4> Function
0
1
0
1
0
1
0
:
Sets the interrupt enabled state. Interrupts are actually enabled after execution of the instruction (return
instruction, etc.) located after the EI instruction, and excess stack space is not used for subsequently
occurring interrupts. Non-maskable interrupts and the SOFTI instruction can be executed at all times without
regard to the EI instruction.
<5> Flags affected
:
<6> Example
:
SK ← 0, L1 ← 0, L0 ← 0
PUSH B
Interrupt generation
Next interrupt enabled
PUSH D
··
··
··
··
·
Interrupts disabled
POP D
POP B
EI
RETI
323
CHAPTER 14
INSTRUCTION SET
DI
(Disable Interrupt)
<1> Operation code
:
1
<2> Number of bytes :
1
<3> Number of states :
4 (4)
<4> Function
0
1
1
1
0
1
0
:
Sets the state in which all interrupts except non-maskable interrupts and interrupts generated by the SOFTI
instruction are disabled. Execution of the DI instruction sets the interrupt disabled state during execution
of the DI instruction.
<5> Flags affected
:
<6> Example
:
SK ← 0, L1 ← 0, L0 ← 0
JYUYO
………
CALL
NEXT:
Interrupts enabled
JYUYO : PUSH
V
PUSH
B
PUSH
D
PUSH
H
Interrupts enabled
…
DI
POP
H
POP
D
POP
B
POP
V
Interrupts disabled
EI
RET
HLT
(Halt)
<1> Operation code
:
<2> Number of bytes :
0
1
0
0
1
0
0
0
0
0
1
1
1
0
1
1
2
<3> Number of states :
12 (8)
<4> Function
:
Sets the HALT mode.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
324
CHAPTER 14
INSTRUCTION SET
STOP
(Stop)
<1> Operation code
:
0
1
0
0
1
0
0
0
1
0
1
1
1
0
1
1
<2> Number of bytes :
2
<3> Number of states :
12 (8)
<4> Function
:
Sets the software STOP mode.
<5> Flags affected
:
SK ← 0, L1 ← 0, L0 ← 0
325
CHAPTER 14
INSTRUCTION SET
14.7 Stacked Instructions
If instructions in the same group, group A or group B, from among the 3 kinds of instructions shown below are
"stacked" in a program (i.e. if located in two or more consecutive addresses), the instruction located at the start point
among the stacked instructions is executed, and thereafter the number of states fundamentally required for execution
of that instruction are expended without any operation being performed (the same state as NOP).
Group A: MVI A, byte
(L1 flag)
Group B: MVI L, byte; LXI H, word
(L0 flag)
When a group A instruction is executed the L1 flag is set, and when a group B instruction is executed the L0 flag
is set, and a check is made of whether instructions in the same group are stacked.
Interrupts are not disabled during stacked instruction execution, but since the L1 and L0 flags are automatically
saved when an interrupt is generated, it is possible, on returning from the interrupt service routine, to determine
whether the next instruction is one which should be given a stacking effect.
Using stacked MVI instructions, a program which clears a 4-byte register located in a specific area of memory
(in this case with 10H as the upper address byte) can be written as shown below.
8
9
A
B
C
D
E
F
0
1
2
3
4
5
6
7
1000
X-REG
Y-REG
1008
Z-REG
W-REG
CLX
: MVI
L,
00H ; CLEAR X-REG
CLY
: MVI
L,
04H ; CLEAR Y-REG
CLZ
: MVI
L,
08H ; CLEAR Z-REG
CLW
: MVI
L,
0CH ; CLEAR W-REG
MVI
H, 40H
MVI
C,
3
XRA
A,
A
LOOP : STAX H+
DCR
C
JR
LOOP
; SET COUNTER
; CLEAR A
; (HL) ← 0, HL ← HL+1
; SKIP IF BORROW
RET
When "CLY" is called, for example, 04H is loaded into the L register and the two stacked instructions MVI L, 08H
and MVI L, 0CH are replaced with an idle cycle (NOP cycle) comprising a total of 14 states, the upper byte of the
address is determined by the next MVI H, 40H instruction and the Y-REG start address "4004H" is loaded into the
HL register pair.
326
CHAPTER 15 OPERATING PRECAUTIONS
Be sure to read the following before using an 87AD series CMOS products.
15.1 RAE Bit Setting
• Target products
:
All products
• Details
:
When using on-chip memory, be sure to set the MM register RAE bit to "1".
If it is not, the on-chip memory cannot be used.
Also, when using the on-chip RAM for stack, be sure to set the RAE bit to "1" before
entering interrupt enable and subroutine call.
Initialization Example 1
CSEG
AT 00
GJMP
START
; Branches to initial routine
LXI
SP, ××××
; Stack pointer setting
MVI
A, ××××1×××B
MOV
MM, A
:
:
:
START :
:
:
:
Initialization Example 2 (Bad example)
CSEG
AT 00
GJMP
START
; Branches to initial routine
LXI
SP, ××××
; Stack pointer setting
CALL
INIT
:
:
:
START :
:
:
:
INIT:
MVI
A, ××××1×××B
MOV
MM, A
:
:
:
In a state in which the RAE bit is not set, the on-chip RAM cannot be used. In addition,
the RAE bit is indefinite when reset is cleared. The indefinite condition varies with a
power source voltage rising condition, unevenness between product lots, difference
between masked PROM and on-chip PROM, etc. Therefore, in Initialization Example
2 above, the RAE bit is indefinite when the INIT routine is called. In case the RAE bit
is reset, stack cannot be used when the INIT routine branches. This will result in an
inadvertent running due to incapability in normal restore from the INIT routine.
327
CHAPTER 15
OPERATING PRECAUTIONS
Even when the RAE bit is set and operates normally, an abnormality will result due to
power source voltage rising condition, unevenness between product lots, difference
between masked PROM and on-chip PROM, etc.
• Remedy
:
As shown in Initialization Example 1 set the stack pointer and MM register before
interrupt enable and subroutine call to enable the use of on-chip RAM.
15.2 Port D/F Setting
• Target products
:
All products
• Details
:
A program to dynamically change the port D/F operation mode (from port mode to
expand mode, and vice versa, from input port to output port, and vice versa and
expansion space change) cannot be emulate by an emulator.
Relevant register: MM register (MM0 to MM2)
MF register
• Remedy
:
Once a mode is set, never the same mode again.
15.3 Timer, Timer/Event Counter Compare Register Setting
• Target products
:
All products
• Details
:
When the compare register value setting competes with compareter match, the latter
takes preference over the former. Therefore, match interrupt occurrence and output
control are disabled. Table 15-1 lists compare register, match signal and match interrupt
of each timer.
Table 15-1. Compare Register, Match Signal and Match Interrupt of Each Timer
Timer and Timer/Event Counter
Compare Register
Match Signal
Match Interrupt
TIMER0
Timer REG0
–
INTT0
_
INTT1
CP0
INTE0
CP1
INTE1
(TM0)
TIMER1
Timer REG1
(TM1)
Timer/event counter
Timer/event counter REG0
(ECNT)
(ETM0)
Timer/event counter REG1
(ETM1)
• Remedy
:
When setting the compare register value do not allow the set value to compete with
the comparator match signal.
328
CHAPTER 15
OPERATING PRECAUTIONS
15.4 Restrictions on Serial Interface and Asynchronous Modes
• Target products
:
µPD78C10
78C11
78C14 (Standards "K" and "E")
78C14A
78CG14
• Details
:
When the serial data reception is made in the asynchronous mode using external clock
SCK signal, the ER flag may not be set normally event if the reception is made normally.
• Remedy
:
Examine the following methods.
(1) Correction by software
When the ER flag is set, issue the transmit request to transmitting side. This is the most desirable method
as a remedy against error occurrence.
(2) Using the internal clock as SCK signal source
Use the internal clock as the SCK signal source. In this case, do not output the SCK from the PC2 pin (MCC2=0,
with PC2 placed in the port mode).
(3) Inputting an external clock signal to PC3/TI
Input an external clock signal to PC3/TI and count TI with the timer. Reverse TO by the timer comparator
match signal and use the reversed TO as SCK signal. In this case, never output SCK from the PC2 pin
(MCC2=0).
[Receving processing initialization program example]
MVI
SMH, 00H
; SCK: TO
MVI
A, ××H
; SML setting
MOV SML, A
MVI
A, ××H
; TM0 (data to scale the TI input ) setting
MOV TM0, A
MVI
TMM, ×××01000B
; TIMER0: TI count, TO is reversed by the TIMER0 match signal.
MVI
A, ××××101×B
; PC1: RXD input
PC2: Port mode
PC3: TI input
MOV MCC, A
:
:
:
ORI
SMH, 08H
Remarks
; Receive enabled
1. Relationship between TI input frequency fTI, data transfer speed B, and clock rate N is as given
below
fTI
B=
2×C×N
(Where C is TM0 set value)
2. The TI input high/low level width is 6/f×× (f××: oscillation frequency) or more. (The level width
is 0.4 µs or more when f××=15 MHz, and the maximum frequency of fTI is 1.25 MHz for 50%
duty.)
329
CHAPTER 15
OPERATING PRECAUTIONS
15.5 Serial Interface Start Bit Input
• Target products
:
All products
• Details
:
When receiving serial data in the asynchronous mode, if approximately 1/2 bit pulse
is input to the RXD pin, the data parity stop bit input is prohibited and an overrun error
may result at the time next data is input.
• Remedy
:
Examine the following methods.
(1) Never input approximately 1/2 bit start bit to the RXD pin.
(2) When the ER flag is set, issue the retransmit request to the transmitting side.
15.6 Serial Interface and Transmission Format Change
• Target products
:
All products
• Details
:
Serial interface may hang up if a transmit data format is changed by manipulating the
SML and SMH registers while transmitting data in the serial register. (This may occur
event if the TXE bit is reset (0)).
The reasons are as follows: When the TXE bit is changed from the set (1) state to reset
(0) state, the send disabled will result after completing data sending from the serial
register. Therefore, if change is made while data is left in the serial register, the serial
interface may not be sent.
• Remedy
:
Examine the following methods.
(1) Set the destination mode so that the transfer format needs not be changed.
(2) When changing transfer format take measure on software so that the transfer format is not be change
until the serial register data is sent out after resetting (0) TXE bit.
15.7 Input Voltage to Analog Input Pin
• Target products
:
All products
• Details
:
When analog input voltage VIAN specified by the A/D converter characteristics exceeds
the specified value accuracy cannot be expected from the value obtained.
Then analog input circuit is as shown in Figure 15-1. It is connected to the sample hold
capacitor via the protection register, protection diode and analog switch. There are one
sample hold capacitor and one A/D converter. The analog input samples the input signal
selected by the analog switch. In this case, if a voltage exceeding the specified analog
voltage is applied to the analog input pin, the analog switch conducts even if it is not
selected. This causes the sample hold capacitor to be charged (When the analog input
voltage ≥VIAN) or discharged (when the analog input voltage ≤VIAN), making the selected
analog input voltage change unreliable.
330
CHAPTER 15
OPERATING PRECAUTIONS
Figure 15-1. Analog Input Circuit Block Diagram
Analog switch
configuration
VDD
AN7
Analog switch
N
P
ANn
To A/D converter
C
• Remedy
:
Sample hold
capacitor
Limit the analog input voltage as described below.
(1) Limit the output voltage in the analog detecting circuit to the specified analog input voltage.
(2) Cramp the analog input pin using a Schottkey Barrier diode.
µ PD78C18
AVDD
VAREF
AN0-7
AVSS
331
CHAPTER 15
OPERATING PRECAUTIONS
15.8 Limitations on Hardware STOP Mode
• Target products
:
µPD78C10
78C11
78C10A (Standards "K")
78C11A (Standards "K")
78C12A (Standards "K")
78C14 (Standards "K" and "E")
78C14A
78CG14
• Details
:
If the hardware STOP mode is executed not in synchronization with the CPU operation,
power supply current consumption may become approximately 20 mA, even after
entering the hardware STOP mode.
• Remedy
:
Use any of the following signals in combination with the STOP input, then use the JR
$ instruction to synchronize the hardware STOP mode with the CPU operation.
• NMI
• RESET
(1) When both NMI and STOP are used
As shown in Figure 15-2, input the power-off detect signal to the NMI pin as an non-maskable interrupt request,
then input the delayed signal thus obtained to the STOP pin as the hardware STOP mode setting signal.
Figure 15-2. When Both NMI and STOP Are Used
87AD Series
Power-off
detecting
signal
NMI
R
STOP
C
332
CHAPTER 15
OPERATING PRECAUTIONS
The operation sequence is as follows:
(a) When the power-off detect signal is input, the NMI routine starts.
(b) Then JR $ instruction is executed as the start of NMI routine, the program is looped to wait STOP.
Determine values of R and C so that the delay of STOP behind NMI is longer than the longest interrupt wait
period 75 states +10 µs (28.75 µs at 12 MHz operation).
Figure 15-3. Control Timing of NMI and STOP
NMI routine
Instruction
execution
JR $
NMI
75 states + 10 µ s or more
VIH
STOP
VIL
Hardware STOP mode
When executing the power off processing before executing the JR $ in the NMI routine, delay of STOP
is required to be larger in proportion to time shortened.
333
CHAPTER 15
OPERATING PRECAUTIONS
(2) When both RESET and STOP are used
During reset period (RESET=low level), STOP input can be acknowledged normally. Therefore, if the RESET
input is activated before entering STOP, a normal hardware STOP mode can be expected.
Figure 15-4. When Both NMI and STOP Are Used
87AD Series
Power-off
detecting
signal
RESET
R
STOP
C
The operation sequence is as follows:
(a) When the power supply off detect signal (RESET signal) enters, the 87AD series is placed in the reset
state.
(b) The RESET signal is caused to be delayed 10 µs or more to change it to be the STOP signal.
(c) The 87AD series enters the hardware STOP mode in the reset state.
However, this method may damage the data memory contents by RESET, in other words, if the RESET signal
is input to the CPU data memory while data is written, the relevant data may be undefined.
Figure 15-5. Control Timing of RESET and STOP
RESET
RESET status
10 µs or more
VIH
STOP
VIL
Hardware STOP mode
334
CHAPTER 15
OPERATING PRECAUTIONS
15.9 How to Use Standby Flag
• Target products
:
All products
• Details
:
Assurance is not given to voltage level where the standby (SB) flag is set again after
the power supply voltage subsequent to entering the software/hardware STOP mode.
(The desirable voltage is maintained in a state where 2.5 V ≤ VDD ≤ operational voltage
range.) Therefore, the SB flag cannot be used for a test as to whether the RAM back
is normal after releasing software/hardware STOP mode.
• Remedy
:
Keep the data retention voltage VDDDR over 2.5 V by hardware in the software/hardware
STOP mode.
15.10 Bus Interface
• Target products
:
All products
• Details
:
In case where a RAM is expanded externally, connecting a comparatively speedy SRAM
may cause large current to run in the read operation due to collision of address output
signal from address/data (PD7 to PD0) with SRAM output signal.
Figure 15-6. µPD78C18 Read Operation
PF7-0
(A8-A14)
Address (High-order)
tAD
PD7-0
(A0-A7)
Address (Low-order)
tLDR
ALE
tRD
RD
(OE)
tAFR (20 ns MAX.)
Data read
SRAM read cycle
(DOUT)
Remark
Symbols in ( ) are SRAM (µPD43256A) pin names.
• Remedy
:
To connect an SRAM, insert gates, etc. between the RD and SRAM OE pins to give
a delay (tDELY) to the RD active signal.
In this case be sure to satisfy the tRD specification as given below.
t0E + tDELY ≤ tRD
335
CHAPTER 15
OPERATING PRECAUTIONS
Sample Solution
µ PD78C18
µ PD74HC04
SRAM
RD
OE
WR
WE
Lead to another
peripheral
15.11 Restrictions on IE-78C11-M Operation
• Target products
:
IE-78C11-M
• Details
:
The IE-78C11-M uses the µPD78C10G-36 as the emulation CPU and includes defects
mentioned in 15.4 Restrictions on Serial Interface and Asynchronous Modes and
15.8 Limitations on Hardware STOP mode. Therefore, the above defects are found
in the course of debugging.
• Remedy
:
If the defective product is replaced by the improved product or trouble-free product is
used for debugging, change emulation CPU (from Standard K of µPD78C10A to any of
standards other than K).
15.12 Electrostatic Withstand Limit of VPP Pin
• Target products
:
µPD78CP18 (Standard "K")
• Details
:
The VPP pin can withstand a maximum of 500V static electricity in the MIL standard
measuring method.
• Remedy
336
:
Take suitable precautions when writing to the PROM or mounting the device.
APPENDIX A
INTROCUTION TO PIGGYBACK PRODUCT
µPD78CG14
On-Chip EPROM Type 8-Bit Microcontroller (with A/D Converter)
The µPD78CG14 8-bit microcontroller allows program memory (standard 27C256/27C256A EPROM) to be
connected by the piggyback method.
The µPD78CG14 is pin-compatible with the µPD78C11A/78C12A/78C14 QUIP type 8-bit shingle-chip microcontrollers
with on-chip mask ROM, and has identical functions.
The µPD78CG14 allows the program to be changed by rewriting the EPROM, and is suitable for µPD78C11A/78C12A/
78C14 evaluation and limited production.
Features
• Compatible with µPD78C11A/78C12A/78C14 QUIP type products.
• Capacity accessible as piggyback memory can be changed by software (16K/8K/4K bytes)
• Program memory addressing capacity: 65280 × 8 bits
• On-chip RAM capacity: 256 × 8 bits
• Standby functions: HALT mode, hardware/software STOP mode
• CMOS
• Single power supply (5 V ± 10%)
Ordering Information
Part Number
Package
µPD78CG14E
64-pin ceramic piggyback QUIP
337
APPENDIX A
INTRODUCTION TO PIGGYBACK PRODUCT
Pin Configuration (Top View)
338
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
VDD 1
28 VDD
A12
2
27 VSS
A7
3
26 A13
A6
4
25 A8
A5
5
24 A9
A4
6
23 A11
A3
7
A2
8
A1
9
20 CE
A0
10
19 I7
I0
11
18 I6
I1
12
17 I5
I2
13
16 I4
VSS
14
15 I3
(Upper pin section)
PA0
PA1
PA2
PA3
PA4
PA5
PA6
PA7
PB0
PB1
PB2
PB3
PB4
PB5
PB6
PB7
PC0/TxD
PC1/RxD
PC2/SCK
PC3/INT2
PC4/TO
PC5/CI
PC6/CO0
PC7/CO1
NMI
INT1
MODE1
RESET
MODE0
X2
X1
VSS
22 VSS
21 A10
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
VDD
STOP
PD7
PD6
PD5
PD4
PD3
PD2
PD1
PD0
PF7
PF6
PF5
PF4
PF3
PF2
PF1
PF0
ALE
WR
RD
AVDD
VAREF
AN7
AN6
AN5
AN4
AN3
AN2
AN1
AN0
AVSS
8
4
PC3/INT2/TI
Timer
PC4/TO
PC5/CI
PC6/CO0
PC7/CO1
Timer/event
counter
VAREF
AVCC
AVSS
8
ALT
G.R
Buffer
8
8
8
8
8
8
8
Data
memory
(256-bytes)
16
8
8
PF7-0/AB15-8
PD7-0/AD7-0
PC7-0
PB7-0
PA7-0
8
8/16
8
8
8
8
Internal data bus
16
16
6
Latch
Latch
PSW
16
A/D
Converter
8
8
6
AN7-0
Port F
INT
Control
8
8
Main
G.R
8
ALU
(8/16)
8
16
INST. REG
INST.
Decoder
16
Read/write
control
VSS
VCC
RD
WR
Standby
control
STOP
System
control
RESET MODE1 MODE0 ALE
CE
INTRODUCTION TO PIGGYBACK PRODUCT
NMI
INT1
8
Port D
Serial I/O
I7-0
8
Port C
PC0/TxD
PC1/RxD
PC2/SCK
8
Port B
OSC
X2
APPENDIX A
16
Latch
INC/DEC
PC
SP
EA
V
A
B
C
D
E
H
L
EA'
V'
A'
B'
C'
D'
E'
H'
L'
Buffer
Port A
X1
Block Diagram
A13-0
14
339
APPENDIX A
INTRODUCTION TO PIGGYBACK PRODUCT
A.1 Pin Functions
A.1.1 Lower pins (µPD78C11A/78C12A/78C14 QUIP type compatible)
Pin Name
PA7 to PA0
Input/Output
Function
I/O
8-bit input/output port, with input/output specifiable bit-wise
I/O
8-bit input/output port, with input/output specifiable bit-wise
I/O/output
Port C
Transmit data
8-bit input/output port, with input/
Serial data output pin
(Port A)
PB7 to PB0
(Port B)
PC0/TXD
PC1/RXD
I/O/input
output specifiable bit-wise
Receive data
Serial data input pin
PC2/SCK
I/O/I/O
Serial clock
Serial clock input/output pin: Output
when internal clock is used, input
when external clock is used
PC3/INT2/TI
I/O/input/input
Interrupt request/timer input
Edge-triggered (falling edge)
maskable interrupt input pin or timer
external clock input pin can also be
used as AC input zero-cross
detection pin
PC4/TO
I/O/output
Timer output
Square wave is output with timer
count time or one internal clock cycle
as one half cycle
PC5/CI
I/O/input
Counter input
Input pin for external pulses to timer/
event counter
PC6/CO0
I/O/output
Counter output 0 & 1
PC7/CO1
Rectangular-wave output
programmable by timer/event
counter
PD7 to PD0/
I/O/I/O
AD7 to AD0
Port D
Address/data bus
8-bit input/output port, with
Functions as multiplexed
input/output specifiable bit-wise
address/data bus when external
memory is used
PF7 to PF0/
AB15 to AB8
340
I/O/output
Port F
Address bus
8-bit input/output port, with
Functions as address bus when
input/output specifiable bit-wise
external memory is used
APPENDIX A
Pin Name
WR
INTRODUCTION TO PIGGYBACK PRODUCT
Input/Output
Output
(Write strobe)
Function
Strobe signal output for external memory write operations. High level
except in external memory data write machine cycles. Becomes highimpedance output when RESET signal is low or in hardware STOP mode.
RD
Output
(Read strobe)
Srtobe signal output for external memory read operations. High level
except in external memory data read machine cycles. Becomes highimpedance output when RESET signal is low or in hardware STOP mode.
ALE
Output
Strobe signal output for external latching of lower address information
(Address latch
output to pins PD7 to PD0 to access external memory. Becomes high-
enable)
impedance output when RESET signal is low or in hardware STOP mode.
MODE0
I/O
Set MODE0 pin to "0" (low level), MODE1 pin to "1" (high level)Note.
MODE1
When MODE0 and MODE1 pins are both set to "1"Note control signal is
(Mode)
output in synchronization with ALE.
NMI
Input
Edge-triggered (falling edge) non-maskable interrupt input pin.
Input
Edge-triggered (rising edge) maskable interrupt input pin; can also be used
(Non-maskable
interrupt)
INT1
(Interrupt
as AC input zero-cross detection pin.
request)
AN7 to AN0
Input
(Analog input)
VAREF
8 analog inputs to A/D converter. AN7 to AN4 can also be used as edgedetected (falling edge) inputs.
Input
(Reference
Dual function as A/D converter reference voltage input pin and A/D
converter operation control pin
voltage)
AVDD
A/D converter power supply pin
(Analog VDD)
AVSS
A/D converter GND pin
(Analog VSS)
X1, X2
System clock oscillation crystal connected inputs. When clock is supplied
(Crystal)
externally, it is input to X1. Input inverted phase clock of X1 to X2.
RESET
Input
Low-level active system reset input
Input
Hardware STOP mode control signal input pin: When driven low, oscillator
(Reset)
STOP
(Stop)
operation stops.
VDD
Positive power supply pin
VSS
GND pin
Note Should be pulled up. The pull-up resistor R specification is: 4 [kΩ] ≤ R ≤ 0.4CYC [kΩ] (tCYC in ns units).
341
APPENDIX A
INTRODUCTION TO PIGGYBACK PRODUCT
A.1.2 Upper pins (27C256/27C256A compatible)
Pin Name
A0 to A13
Input/Output
Output
Function
Outputs 14 bits (PC0 to PC13) of program counter
After Reset
Undefined
comprising 27C256/27C256A address signals (A0 to A13).
I0 to I7
Input
Inputs data (00 to 07) read from 27C256/27C256A.
CE (20)
Output
Supplies chip enable signal to 27C256/27C256A CE pin.
High in hardware/software STOP & HALT mode, low at
all other times.
VDD (1)
Supplies VCC power supply (VPP) to 27C256/27C256A at
same potential as lower VDD pin.
VDD (28)
Supplies VCC power supply (VCC) to 27C256/27C256A at
same potential as lower VDD pin.
VSS (14)
Connected to 27C256/27C256A GND pin at same
potential as lower VSS pin.
VSS (22)
Supplies OE signal (always low) to 27C256/27C256A at
same potential as lower VSS pin.
VSS (27)
Supplies A14 signal (always low) to 27C256/27C256A at
same potential as lower VSS pin.
A.2 Memory Configuration
The memory of the µPD78CG14 allows implementation of the same functions and configuration as the µPD78C11A/
78C12A/78C14. Also, the piggyback EPROM address range can be selected by means of the memory mapping
register for efficient setting of external memory (excluding EPROM).
The vector addresses, call table area and data memory area are the same for all three product types.
The memory maps are shown in Figures A-1 to A-3.
342
APPENDIX A
INTRODUCTION TO PIGGYBACK PRODUCT
Figure A-1. Memory Map (µPD78C14 Mode)
0000H
Piggyback
EPROM
0000H
RESET
0004H
NMI
0008H
INTT0/INTT1
0010H
INT1/INT2
0018H
INTE0/INTE1
0020H
INTEIN/INTAD
0028H
INTSR/INTST
0060H
SOFTI
0080H
Low address
0081H
High address
0082H
Low address
0083H
High address
00BEH
Low address
00BFH
High address
16384 × 8 bits
3FFFH
4000H
External
memory
48896 × 8 bits
FF00H
On-chip RAM
256 × 8 bits







Call table
FFFFH
Note
Standby area
FEFFH













 t=0


 t=1


 t = 31

00C0H
User's area
3FFFH
Note Can only be used when the RAE bit of the MM register is 1.
343
APPENDIX A
INTRODUCTION TO PIGGYBACK PRODUCT
Figure A-2. Memory Map (µPD78C12A Mode)
0000H
Piggyback
EPROM
0000H
RESET
0004H
NMI
0008H
INTT0/INTT1
0010H
INT1/INT2
0018H
INTE0/INTE1
0020H
INTEIN/INTAD
0028H
INTSR/INTST
0060H
SOFTI
0080H
Low address
0081H
High address
0082H
Low address
0083H
High address
00BEH
Low address
00BFH
High address
8192 × 8 bits
1FFFH
2000H
External
memory
57088 × 8 bits
FF00H
On-chip RAMNote
256 × 8 bits
Call table
FFFFH







Standby area
FEFFH












00C0H
User's area
1FFFH
Note Can only be used when the RAE bit of the MM register is 1.
344

 t=0


 t=1


 t = 31

APPENDIX A
INTRODUCTION TO PIGGYBACK PRODUCT
Figure A-3. Memory Map (µPD78C11A Mode)
0000H
Piggyback
EPROM
0000H
RESET
0004H
NMI
0008H
INTT0/INTT1
0010H
INT1/INT2
0018H
INTE0/INTE1
0020H
INTEIN/INTAD
0028H
INTSR/INTST
0060H
SOFTI
0080H
Low address
0081H
High address
0082H
Low address
0083H
High address
00BEH
Low address
00BFH
High address
4096 × 8 bits
0FFFH
1000H
External
memory
61184 × 8 bits
FF00H
On-chip RAMNote
256 × 8 bits
Call table
FFFFH







Standby area
FEFFH













 t=0


 t=1


 t = 31

00C0H
User's area
0FFFH
Note Can only be used when the RAE bit of the MM register is 1.
345
APPENDIX A
INTRODUCTION TO PIGGYBACK PRODUCT
A.3 Memory Mapping Register (MM)
This is an 8-bit register in which the function of specifying the piggyback EPROM access address (MM6 & MM7)
is added to the control functions of the µPD78C11A/78C12A/78C14.
The configuration of the memory mapping register is shown in Figure A-4.
When MM7 and MM6 are set to 00, piggyback EPROM addresses 0000H to 3FFFH (16K bytes) are accessed,
and the external memory capacity is 48K bytes. When set to 10, addresses 0000H to 0FFFH (4K bytes) are accessed,
and thus the external memory capacity is 60K bytes.
The MM7 and MM6 bits are only valid in the µPD78CG14/78CP14Note; if data is written to these bits in the
µPD78C11A/78C12A/78C14, it is ignored by the CPU. Therefore, a program developed in piggyback mode can be
transferred without modification to mask ROM.
In the µPD78CG14, MM7, MM6, MM2, MM1 and MM0 are initialized to 0 by RESET input. Therefore, the
µPD78C14 starts operating in single-chip mode.
Also, the RAE bit is undefined after RESET input, and must be initialized at the start of the program.
Note See CHAPTER 12 PROM ACCESSES (µPD78CP18/78CP14 ONLY).
346
APPENDIX A
INTRODUCTION TO PIGGYBACK PRODUCT
Figure A-4. Memory Mapping Register Format (µPD78CG14)
MM7 MM6
5
4
–
–
3
2
1
0
RAE MM2 MM1 MM0
0
0
0
0
0
1
0
1
0
1
0
0
1
1
1
1
Port mode
6
PD7 to PD0 = input port
PF7 to PF0 = port mode
Single chip
PD7 to PD0 = output port
PF7 to PF0 = port mode
256 bytes
PD7 to PD0 = expansion mode
PF7 to PF0 = port mode
4K bytes
PD7 to PD0  = expansion mode

PF3 to PF0 
PF7 to PF4 = port mode
0
16K bytes
PD7 to PD0  = expansion mode

PF5 to PF0 
PF7 & PF6 = port mode
1
48K/56K/
60K bytes Note
PD7 to PD0  = expansion mode

PF7 to PF0 
Expansion mode
7
Note Depending on setting of bits MM7 & MM6
On-chip RAM access
0
Disable
1
Enable
Piggyback memory access
0
0
Access to addresses 0000H to 3FFFH of EPROM
located in upper pin section
( µ PD78C14 mode)
0
1
Access to addresses 0000H to 1FFFH of above
EPROM
( µ PD78C12A mode)
1
0
Access to addresses 0000H to 0FFFH of above
EPROM
( µ PD78C11A mode)
1
1
Setting prohibited
347
APPENDIX A
INTRODUCTION TO PIGGYBACK PRODUCT
A.4 Interface with EPROM
Figure A-5. Connection to 27C256A
µ PD78CG14
27C256A
VDD(1)
VPP
VDD(28)
VCC
A0 - A13
A0 - A13
VSS(27)
A14
VSS(22)
OE
CE(20)
CE
I0 - I7
VSS(14)
O0 - O7
GND
Caution When the µPD2764/27C64/27128 is used, a high-level signal must be input to pin 27 (PGM). For
this reason, pin 27 only should not be inserted in the socket, but should receive a high-level input
externally.
348
APPENDIX B
DEVELOPMENT TOOLS
The following development tools are available for system development using 87AD series products.
Language Processor
87AD series
This program converts a program written in mnemonics into object code which can be
relocatable assembler
executed by a microcontroller.
(RA87)
In addition, functions are provided for automatic symbol table generation, branch
instruction optimization processing, etc.
Host
machine
OS
Supply medium
(Product name)
MS-DOSTM
3.5-inch 2HD
µS5A13RA87
5-inch 2HD
µS5A10RA87
PC DOSTM
3.5-inch 2HC
µS7B13RA87
(Ver.3.1)
5-inch 2HC
µS7B10RA87
Ver. 2.11
~
PC-9800 series
Ordering code
Ver. 5.00ANote
IBM PC/ATTM
Note Ver. 5.00/5.00A are provided with a task swapping function, but this software cannot use the function.
Remark
Operation of the assembler is guaranteed only on the host machines and operating systems quoted
above.
349
APPENDIX B
DEVELOPMENT TOOLS
PROM Writing Tools
Hardware
PG-1500
This PROM programmer allows programming, in standalone mode or via operation from
a host machine, of a single-chip microcontroller with on-chip PROM by connection of
the board provided and a separately available programmer adapter.
It also permits programming of typical PROMs from 256K bits to 1M bits.
PA-78CP14CW
PROM programmer adapter for µPD78CP14/78CP18, used connected to the PG-1500.
/GF/GQ/KB/L
Software
PA-78CP14CW
For µPD78CP14CW/78CP14DW/78CP18CW/78CP18DW
PA-78CP14GF
For µPD78CP14GF-3BE/78CP18GF-3BE
PA-78CP14GQ
For µPD78CP14G-36/78CP14R/78CP18GQ-36
PA-78CP14KB
For µPD78CP14KB/78CP18KB
PA-78CP14L
For µPD78CP14L
PG-1500 controller
Connects PG-1500 and host machine via a serial and parallel interface, and controls
the PG-1500 on the host machine.
Host
machine
OS
Supply medium
(Product name)
MS-DOS
3.5-inch 2HD
µS5A13PG1500
5-inch 2HD
µS5A10PG1500
PC DOS
3.5-inch 2HD
µS7B13PG1500
(Ver.3.1)
5-inch 2HC
µS7B10PG1500
Ver. 3.10
~
PC-9800 series
Ordering code
Ver. 5.00ANote
IBM PC/AT
Note Ver. 5.00/5.00A are provided with a task swapping function, but this software cannot use the function.
Remark
Operation of PG-1500 controller is guaranteed only on the host machines and operating systems quoted
above.
350
APPENDIX B
DEVELOPMENT TOOLS
Debugging Tools
An in-circuit emulator (IE-78C11-M) is available as a program debugging tool for 87AD series products. The system
configuration is shown below.
Hardware
IE-78C11-M
The IE-78C11-M is an in-circuit emulator for the 87AD series.
The IE-78C11-M is used alone for a plastic QUIP, or in conjunction with the conversion
socket for a plastic shrink DIP. Efficient debugging is possible by connection to a host
machine.
EV-9001-64
Conversion socket for use with a plastic shrink DIP.
Used in conjunction with the IE-78C11-M.
EV-9200G-64
64-pin WQFN socket. Can be used in conjunction with the µPD78CP14KB/
78CP18KB, by which 64-pin plastic QFP products with window are superseded.
Software
IE-78C11-M control
Connects the IE-78C11-M to the host machine via RS-232-C, and controls the IE-
program (IE controller)
78C11-M on the host machine.
Host
Ordering code
machine
OS
Supply medium
(Product name)
MS-DOS
3.5-inch 2HD
µS5A13IE78C11
5-inch 2HD
µS5A10IE78C11
5-inch 2HC
µS7B10IE78C11
Ver. 2.11
~
PC-9800 series
Ver. 3.30D
IBM PC/AT
PC DOS
(Ver.3.1)
Remark
Operation of IE controller is guaranteed only on the host machines and operating systems quoted above.
Related Documents
• Hardware tools
•
IE-78C11 Control Program User's Manual (EEU-1368)
• Software tools
•
RA87 Assembler Package User's Manual
PC-9800 Series (MS-DOS) Based, IBM PC (PC DOS) Based (EEM-1202)
•
Macro Processor User's Manual (EEM-1041)
351
[MEMO]
352
APPENDIX C INDEX OF INSTRUCTIONS (ALPHABETICAL ORDER)
Instruction
Page
[A]
Instruction
Page
Instruction
Page
CALL
word
316
EI
323
word
317
EQA
A, r
261
305
EQA
r, A
262
EQAW
wa
289
EQAX
rpa
269
304
EQI
A, byte
282
ACI
A, byte
271
CALT
ACI
r, byte
271
CLC
ACI
sr2, byte
271
ADC
A, r
252
[D]
ADC
r, A
253
DAA
ADCW
wa
285
DADC
EA, rp3
294
EQI
r, byte
282
ADCX
rpa
263
DADD
EA, rp3
294
EQI
sr2, byte
282
ADD
A, r
252
DADDNC
EA, rp3
295
EQIW
wa, byte
292
ADD
r, A
252
DAN
EA, rp3
296
ESUB
EA, r2
295
ADDNC
A, r
253
DCR
r2
302
EXA
241
ADDNC
r, A
254
DCRW
wa
302
EXH
241
ADDNCW
wa
285
DCX
EA
303
EXX
240
ADDNCX
rpa
264
DCX
rp
303
ADDW
wa
285
DEQ
EA, rp3
298
[G]
ADDX
rpa
263
DGT
EA, rp3
297
GTA
A, r
259
ADI
A, byte
270
DI
324
GTA
r, A
259
ADI
r, byte
270
DIV
r2
300
GTAW
wa
288
ADI
sr2, byte
270
DLT
EA, rp3
298
GTAX
rpa
267
ADINC
A, byte
272
DMOV
EA, rp3
242
GTI
A, byte
279
ADINC
r, byte
272
DMOV
EA, sr4
243
GTI
r, byte
279
ADINC
sr2, byte
272
DMOV
rp3, EA
242
GTI
sr2, byte
279
ANA
A, r
257
DMOV
sr3, EA
242
GTIW
wa, byte
291
ANA
r, A
257
DNE
EA, rp3
298
ANAW
wa
287
DOFF
EA, rp3
299
[H]
ANAX
rpa
266
DON
EA, rp3
299
HLT
ANI
A, byte
276
DOR
EA, rp3
297
ANI
r, byte
276
DRLL
EA
310
[I]
ANI
sr2, byte
276
DRLR
EA
311
INR
r2
301
ANIW
wa, byte
290
DSBB
EA, rp3
296
INRW
wa
301
DSLL
EA
311
INX
EA
302
DSLR
EA
312
INX
rp
301
321
DSUB
EA, rp3
295
241
DSUBNB
EA, rp3
296
[J]
DXR
EA, rp3
297
JB
313
JEA
315
[B]
BIT
bit, wa
BLOCK
[C]
CALB
CALF
word
316
[E]
317
EADD
EA, r2
294
324
JMP
word
313
JR
word
314
353
APPENDIX C
Instruction
JRE
word
INDEX OF INSTRUCTIONS (ALPHABETICAL ORDER)
Page
315
[L]
Instruction
NEI
NEIW
sr2, byte
wa, byte
NOP
Page
Instruction
Page
281
292
[S]
SBB
A, r
255
323
SBB
r, A
255
SBBW
wa
286
SBBX
rpa
265
LBCD
word
246
LDAW
wa
238
[O]
LDAX
rpa2
240
OFFA
A, r
262
SBCD
word
243
LDEAX
rpa3
248
OFFAW
wa
290
SBI
A, byte
274
LDED
word
246
OFFAX
rpa
269
SBI
r, byte
274
LHLD
word
247
OFFI
A, byte
284
SBI
sr2, byte
274
LSPD
word
247
OFFI
r, byte
284
SDED
word
243
LTA
A, r
260
OFFI
sr2, byte
284
SHLD
word
244
LTA
r, A
260
OFFIW
wa, byte
293
SK
f
321
LTAW
wa
289
ONA
A, r
262
SKIT
irf
322
LTAX
rpa
268
ONAW
wa
290
SKN
f
322
LTI
A, byte
280
ONAX
rpa
269
SKNIT
irf
322
LTI
r, byte
280
ONI
A, byte
283
SLL
r2
308
LTI
sr2, byte
280
ONI
r, byte
283
SLLC
r2
309
LTIW
wa, byte
291
ONI
sr2, byte
283
SLR
r2
309
LXI
rp2, word
250
ONIW
wa, byte
292
SLRC
r2
310
ORA
A, r
257
SOFTI
ORA
r, A
258
SSPD
word
244
[M]
318
MOV
r1, A
233
ORAW
wa
288
STAW
wa
238
MOV
A, r1
233
ORAX
rpa
266
STAX
rpa2
239
MOV
sr, A
234
ORI
A, byte
277
STEAX
rpa3
245
MOV
A, sr1
234
ORI
r, byte
277
STC
305
MOV
r, word
235
ORI
sr2, byte
277
STOP
325
MOV
word, r
235
ORIW
wa, byte
291
SUB
A, r
254
MUL
r2
300
SUB
r, A
255
MVI
r, byte
236
[P]
SUBNB
A, r
256
MVI
sr2, byte
236
POP
rp1
250
SUBNB
r, A
256
MVIW
wa, byte
237
PUSH
rp1
249
SUBNBW
wa
287
MVIX
rpa1, byte
237
SUBNBX
rpa
265
SUBW
wa
286
[R]
[N]
RET
319
SUBX
rpa
264
NEA
A, r
261
RETI
320
SUI
A, byte
273
NEA
r, A
261
RETS
319
SUI
r, byte
273
NEAW
wa
289
RLD
306
SUI
sr2, byte
273
NEAX
rpa
268
RLL
r2
307
SUINB
A, byte
275
305
RLR
r2
308
SUINB
r, byte
275
RRD
307
SUINB
sr2, byte
275
NEGA
NEI
A, byte
281
NEI
r, byte
281
354
APPENDIX C
Instruction
INDEX OF INSTRUCTIONS (ALPHABETICAL ORDER)
Page
[T]
TABLE
251
[X]
XRA
A, r
258
XRA
r, A
258
XRAW
wa
288
XRAX
rpa
267
XRI
A, byte
278
XRI
r, byte
278
XRI
sr2, byte
278
355