NSC COP8-PGMA-68PF1 8-bit cmos flash microcontroller with 8k memory, dual op amps, virtual eerom, temperature sensor,10-bit a/d and brownout reset Datasheet

February 2004
COP8AME9
8-Bit CMOS Flash Microcontroller with 8k Memory, Dual
Op Amps, Virtual EEPROM, Temperature Sensor, 10-Bit
A/D and Brownout Reset
1.0 General Description
The COP8AME9 Flash microcontroller is a highly integrated
COP8™ Feature core device, with 8k Flash memory and
advanced features including Virtual EEPROM, dual Op
Amps (one programmable gain), temperature sensor, A/D,
High Speed Timers, USART, and Brownout Reset. The
COP8AME9 has True In-System Programmable Flash
memory with high-endurance (100k erase/write cycles), and
is well suited for applications requiring real-time data collection and processing, multiple sensory interface, and remote
monitoring. The same device is used for development, preproduction and volume production with a range of COP8
software and hardware development tools.
Device described in this datasheet:
Device
Flash
Program
Memory
(bytes)
RAM
(bytes)
Brownout
Voltage
I/O
Pins
Packages
Temperature
COP8AME9
8k
512
4.17 to 4.5V
21
28 DIP/SOIC
−40˚C to +85˚C
2.0 Features
KEY FEATURES
n 8 kbytes Flash Program Memory with High Security
n 512 bytes SRAM
n 10-bit Successive Approximation Analog to Digital
Converter (up to 6 external channels)
n Op Amp Specification:
— One programmable gain (1, 2, 5, 10, 20, 49, 98) with
adjustable offset voltage nulling
— One general purpose with all I/O terminals accessible
— 1 MHz GBW
— Low offset voltage
— High input impedance
— Rail-to-rail input/output
n Temperature Sensing Diode
n True In-System Programmability of Flash Memory with
100k erase/write cycles
n Dual Clock Operation providing Enhanced Power Save
Modes – HALT/IDLE
n 100% Precise Analog Emulation
n Single supply operation: 4.5V–5.5V
n Three 16-bit timers:
— Timers T2 and T3 can operate at 50 ns resolution
— Processor Independent PWM mode
— External Event counter mode
— Input Capture mode
n Brownout Reset
n 20 high sink-current I/Os
n USART
n Virtual EEPROM using Flash Program Memory
n 7 input analog MUX with selectable output destination
OTHER FEATURES
n Quiet Design (low radiated emissions)
n Multi-Input Wake-up with optional interrupts
n MICROWIRE/PLUS (Serial Peripheral Interface
Compatible)
n Clock Doubler for 20 MHz operation from 10 MHz
Oscillator
n Thirteen multi-source vectored interrupts servicing:
— External Interrupt
— USART (2)
— Idle Timer T0
— Three Timers (each with 2 interrupts)
— MICROWIRE/PLUS Serial peripheral interface
— Multi-Input Wake-Up
— Software Trap
n Idle Timer with programmable interrupt interval
n 8-bit Stack Pointer SP (stack in RAM)
n Two 8-bit Register Indirect Data Memory Pointers
n True bit manipulation
n WATCHDOG and Clock Monitor logic
n Software selectable I/O options
— TRI-STATE Output/High Impedance Input
— Push-Pull Output
— Weak Pull-Up Input
n Schmitt trigger inputs on I/O ports
n Temperature range: –40˚C to +85˚C
n Packaging: 28 DIP, and 28 SOIC
COP8™ is a trademark of National Semiconductor Corporation.
© 2004 National Semiconductor Corporation
DS200063
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COP8AME9 8-Bit CMOS Flash Based Microcontroller with 8k Memory, Dual Op Amps, Virtual
EEPROM, Temperature Sensor, 10-Bit A/D and Brownout Reset
PRELIMINARY
COP8AME9
3.0 Block Diagram
20006301
4.0 Ordering Information
Part Numbering Scheme
COP8
AM
E
9
E
NA
8
Family and
Feature Set
Indicator
Program
Memory
Size
Program
Memory
Type
No. Of Pins
Package
Type
Temperature
AM = 4.17V - 4.5V Brownout
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E = 8k
9 = Flash
2
E = 28 Pin
NA = DIP
MW = SOIC
8 = -40 to +85˚C
3
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COP8AME9
Table of Contents
1.0 General Description ..................................................................................................................................... 1
2.0 Features ....................................................................................................................................................... 1
3.0 Block Diagram .............................................................................................................................................. 2
4.0 Ordering Information .................................................................................................................................... 2
5.0 Connection Diagram .................................................................................................................................... 6
6.0 Architectural Overview ................................................................................................................................. 8
6.1 EMI REDUCTION ...................................................................................................................................... 8
6.2 IN-SYSTEM PROGRAMMING AND VIRTUAL EEPROM ........................................................................ 8
6.3 DUAL CLOCK AND CLOCK DOUBLER ................................................................................................... 8
6.4 TRUE IN-SYSTEM EMULATION .............................................................................................................. 8
6.5 ARCHITECTURE ..................................................................................................................................... 8
6.6 INSTRUCTION SET ................................................................................................................................. 8
6.6.1 Key Instruction Set Features ............................................................................................................... 8
6.6.2 Single Byte/Single Cycle Code Execution ......................................................................................... 8
6.6.3 Many Single-Byte, Multi-Function Instructions .................................................................................... 8
6.6.4 Bit-Level Control .................................................................................................................................. 9
6.6.5 Register Set ......................................................................................................................................... 9
6.7 PACKAGING/PIN EFFICIENCY ................................................................................................................ 9
7.0 Absolute Maximum Ratings ....................................................................................................................... 10
8.0 Electrical Characteristics ............................................................................................................................ 10
9.0 Pin Descriptions ......................................................................................................................................... 15
9.1 EMULATION CONNECTION ................................................................................................................... 16
10.0 Functional Description .............................................................................................................................. 16
10.1 CPU REGISTERS ................................................................................................................................. 16
10.2 PROGRAM MEMORY ........................................................................................................................... 17
10.3 DATA MEMORY .................................................................................................................................... 17
10.4 DATA MEMORY SEGMENT RAM EXTENSION .................................................................................. 17
10.4.1 Virtual EEPROM .............................................................................................................................. 18
10.5 OPTION REGISTER ............................................................................................................................. 18
10.6 SECURITY ............................................................................................................................................ 19
10.7 RESET ................................................................................................................................................... 19
10.7.1 External Reset ................................................................................................................................. 20
10.7.2 On-Chip Brownout Reset ................................................................................................................. 20
10.8 OSCILLATOR CIRCUITS ...................................................................................................................... 21
10.8.1 Oscillator .......................................................................................................................................... 21
10.8.2 Clock Doubler .................................................................................................................................. 22
10.9 CONTROL REGISTERS ....................................................................................................................... 22
10.9.1 CNTRL Register (Address X'00EE) ................................................................................................. 22
10.9.2 PSW Register (Address X'00EF) ..................................................................................................... 22
10.9.3 ICNTRL Register (Address X'00E8) ................................................................................................ 23
10.9.4 T2CNTRL Register (Address X'00C6) ............................................................................................. 23
10.9.5 T3CNTRL Register (Address X'00B6) ............................................................................................. 23
10.9.6 HSTCR Register (Address X'00AF) ................................................................................................ 23
10.9.7 ITMR Register (Address X'00CF) .................................................................................................... 23
10.9.8 ENAD Register (Address X'00CB) .................................................................................................. 23
11.0 In-System Programming ........................................................................................................................... 24
11.1 INTRODUCTION ................................................................................................................................... 24
11.2 FUNCTIONAL DESCRIPTION .............................................................................................................. 24
11.3 REGISTERS .......................................................................................................................................... 24
11.3.1 ISP Address Registers ..................................................................................................................... 24
11.3.2 ISP Read Data Register .................................................................................................................. 24
11.3.3 ISP Write Data Register ................................................................................................................... 24
11.3.4 ISP Write Timing Register ................................................................................................................ 25
11.4 MANEUVERING BACK AND FORTH BETWEEN FLASH MEMORY AND BOOT ROM ..................... 25
11.5 FORCED EXECUTION FROM BOOT ROM ......................................................................................... 26
11.6 RETURN TO FLASH MEMORY WITHOUT HARDWARE RESET ....................................................... 26
11.7 MICROWIRE/PLUS ISP ........................................................................................................................ 26
11.8 USER ISP AND VIRTUAL E2 ................................................................................................................ 27
11.9 RESTRICTIONS ON SOFTWARE WHEN CALLING ISP ROUTINES IN BOOT ROM ....................... 29
11.10 FLASH MEMORY DURABILITY CONSIDERATIONS ........................................................................ 29
12.0 Timers ....................................................................................................................................................... 30
12.1 TIMER T0 (IDLE TIMER) ...................................................................................................................... 30
COP8AME9
Table of Contents
(Continued)
12.1.1 ITMR Register ..................................................................................................................................
12.2 TIMER T1, TIMER T2, AND TIMER T3 ................................................................................................
12.2.1 Timer Operating Speeds ..................................................................................................................
12.2.2 Mode 1. Processor Independent PWM Mode .................................................................................
12.2.3 Mode 2. External Event Counter Mode ...........................................................................................
12.2.4 Mode 3. Input Capture Mode ..........................................................................................................
12.3 TIMER CONTROL FLAGS ....................................................................................................................
12.4 TIMER T2 OPERATION IN IDLE MODE ..............................................................................................
12.4.1 Timer T2 Clocking Scheme .............................................................................................................
13.0 Power Saving Features ............................................................................................................................
13.1 POWER SAVE MODE CONTROL REGISTER ....................................................................................
13.2 OSCILLATOR STABILIZATION .............................................................................................................
13.3 HIGH SPEED MODE OPERATION ......................................................................................................
13.3.1 High Speed Halt Mode ....................................................................................................................
13.3.1.1 Entering The High Speed Halt Mode .........................................................................................
13.3.1.2 Exiting The High Speed Halt Mode ...........................................................................................
13.3.1.3 HALT Exit Using Reset ..............................................................................................................
13.3.1.4 HALT Exit Using Multi-Input Wake-up .......................................................................................
13.3.1.5 Options .......................................................................................................................................
13.3.2 High Speed Idle Mode .....................................................................................................................
13.4 DUAL CLOCK MODE OPERATION ......................................................................................................
13.4.1 Dual Clock HALT Mode ...................................................................................................................
13.4.1.1 Entering The Dual Clock Halt Mode ..........................................................................................
13.4.1.2 Exiting The Dual Clock Halt Mode .............................................................................................
13.4.1.3 HALT Exit Using Reset ..............................................................................................................
13.4.1.4 HALT Exit Using Multi-Input Wake-up .......................................................................................
13.4.1.5 Options .......................................................................................................................................
13.4.2 Dual Clock Idle Mode ......................................................................................................................
13.5 LOW SPEED MODE OPERATION .......................................................................................................
13.5.1 Low Speed HALT Mode ...................................................................................................................
13.5.1.1 Entering The Low Speed Halt Mode .........................................................................................
13.5.1.2 Exiting The Low Speed Halt Mode ............................................................................................
13.5.1.3 HALT Exit Using Reset ..............................................................................................................
13.5.1.4 HALT Exit Using Multi-Input Wake-up .......................................................................................
13.5.1.5 Options .......................................................................................................................................
13.5.2 Low Speed Idle Mode ......................................................................................................................
13.6 MULTI-INPUT WAKE-UP ......................................................................................................................
14.0 USART .....................................................................................................................................................
14.1 USART CONTROL AND STATUS REGISTERS ...................................................................................
14.2 DESCRIPTION OF USART REGISTER BITS ......................................................................................
14.3 ASSOCIATED I/O PINS ........................................................................................................................
14.4 USART OPERATION ............................................................................................................................
14.4.1 Asynchronous Mode ........................................................................................................................
14.4.2 Synchronous Mode ..........................................................................................................................
14.5 FRAMING FORMATS ............................................................................................................................
14.6 USART INTERRUPTS ..........................................................................................................................
14.7 BAUD CLOCK GENERATION ..............................................................................................................
14.8 EFFECT OF HALT/IDLE .......................................................................................................................
14.9 DIAGNOSTIC ........................................................................................................................................
14.10 ATTENTION MODE .............................................................................................................................
14.11 BREAK GENERATION ........................................................................................................................
15.0 A/D Converter ...........................................................................................................................................
15.1 9.1 OPERATING MODES .....................................................................................................................
15.1.1 A/D Control Register ........................................................................................................................
15.1.1.1 Channel Select ...........................................................................................................................
15.1.1.2 Multiplexor Output Select ...........................................................................................................
15.1.1.3 Mode Select ...............................................................................................................................
15.1.1.4 Prescaler Select .........................................................................................................................
15.1.1.5 Busy Bit ......................................................................................................................................
15.1.2 A/D Result Registers .......................................................................................................................
15.2 PROGRAMMABLE GAIN AMPLIFIER ..................................................................................................
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(Continued)
15.2.1 Programmable Gain Amplifier Settling Time ...................................................................................
15.2.2 Programmable Gain Amplifier Offset Calibration .............................................................................
15.2.3 Trimming the Offset on the Programmable Gain Amplifier .............................................................
15.3 A/D OPERATION ...................................................................................................................................
15.3.1 Prescaler ..........................................................................................................................................
15.4 ANALOG INPUT AND SOURCE RESISTANCE CONSIDERATIONS ..................................................
16.0 Temperature Sensor .................................................................................................................................
16.1 GENERAL DESCRIPTION ....................................................................................................................
16.2 OPERATION ..........................................................................................................................................
16.2.1 Procedure for Reading the Temperature Sensor Voltage ...............................................................
17.0 Stand-Alone Amplifier ...............................................................................................................................
17.1 BLOCK DIAGRAM ................................................................................................................................
18.0 Interrupts ..................................................................................................................................................
18.1 INTRODUCTION ...................................................................................................................................
18.2 MASKABLE INTERRUPTS ...................................................................................................................
18.3 VIS INSTRUCTION ...............................................................................................................................
18.3.1 VIS Execution ..................................................................................................................................
18.4 NON-MASKABLE INTERRUPT ............................................................................................................
18.4.1 Pending Flag ....................................................................................................................................
18.4.2 Software Trap ..................................................................................................................................
18.4.2.1 Programming Example: External Interrupt .................................................................................
18.5 PORT L INTERRUPTS ..........................................................................................................................
18.6 INTERRUPT SUMMARY .......................................................................................................................
19.0 WATCHDOG/Clock Monitor .....................................................................................................................
19.1 CLOCK MONITOR ................................................................................................................................
19.2 WATCHDOG/CLOCK MONITOR OPERATION ....................................................................................
19.3 WATCHDOG AND CLOCK MONITOR SUMMARY ..............................................................................
19.4 DETECTION OF ILLEGAL CONDITIONS ............................................................................................
20.0 MICROWIRE/PLUS ..................................................................................................................................
20.1 MICROWIRE/PLUS OPERATION .........................................................................................................
20.1.1 MICROWIRE/PLUS Master Mode Operation ..................................................................................
20.1.2 MICROWIRE/PLUS Slave Mode Operation ....................................................................................
20.1.2.1 Alternate SK Phase Operation and SK Idle Polarity .................................................................
21.0 Memory Map ............................................................................................................................................
22.0 Instruction Set ..........................................................................................................................................
22.1 INTRODUCTION ...................................................................................................................................
22.2 INSTRUCTION FEATURES ..................................................................................................................
22.3 ADDRESSING MODES .........................................................................................................................
22.3.1 Operand Addressing Modes ............................................................................................................
22.3.2 Tranfer-of-Control Addressing Modes ..............................................................................................
22.4 INSTRUCTION TYPES .........................................................................................................................
22.4.1 Arithmetic Instructions ......................................................................................................................
22.4.2 Transfer-of-Control Instructions .......................................................................................................
22.4.3 Load and Exchange Instructions .....................................................................................................
22.4.4 Logical Instructions ..........................................................................................................................
22.4.5 Accumulator Bit Manipulation Instructions .......................................................................................
22.4.6 Stack Control Instructions ................................................................................................................
22.4.7 Memory Bit Manipulation Instructions .............................................................................................
22.4.8 Conditional Instructions ...................................................................................................................
22.4.9 No-Operation Instruction ..................................................................................................................
22.5 REGISTER AND SYMBOL DEFINITION ..............................................................................................
22.6 INSTRUCTION SET SUMMARY ..........................................................................................................
22.7 INSTRUCTION EXECUTION TIME ......................................................................................................
23.0 Development Support ..............................................................................................................................
23.1 TOOLS ORDERING NUMBERS FOR THE COP8S/C/A FLASH FAMILY DEVICES ..........................
23.2 COP8 TOOLS OVERVIEW ...................................................................................................................
23.3 WHERE TO GET TOOLS .....................................................................................................................
24.0 Revision History .......................................................................................................................................
25.0 Physical Dimensions ................................................................................................................................
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COP8AME9
Table of Contents
COP8AME9
5.0 Connection Diagram
20006364
Top View
See NS Package Number M28B or N28B
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6
Port
Type
In System
Emulation Mode
Alt. Fun
28-Pin
DIP/SOIC
L0
I/O
MIWU or Low Speed OSC In
3
L1
I/O
MIWU or CKX or Low Speed OSC Out
4
L2
I/O
MIWU or TDX
5
L3
I/O
MIWU or RDX
6
L4
I/O
MIWU or T2A
7
L5
I/O
MIWU or T2B
8
L6
I/O
MIWU or T3A
9
L7
I/O
MIWU or T3B
10
G0
I/O
INT
a
Input
22
POUT
23
G1
I/O
WDOUT
G2
I/O
T1B
Output
24
G3
I/O
T1A
Clock
25
G4
I/O
SO
26
G5
I/O
SK
27
G6
I
SI
28
G7
I
CKO
1
B2
I/O
ADCH10
11
B3
I/O
ADCH11 or AMP1 Output
12
B4
I/O
ADCH12 or AMP1 − Input
13
B5
I/O
ADCH13 or AMP1 + Input
14
B6
I/O
ADCH14 or A/D MUX OUT
15
B7
I/O
ADCH15 or A/D IN
16
DVCC
VCC
DGND
GND
AVCC
20
17
19
AGND
18
CKI
I
RESET
I
2
RESET
21
a. G1 operation as WDOUT is controlled by Option Register bit 2.
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COP8AME9
Pinouts for 28-Pin Packages
COP8AME9
be bypassed by jumpers on the final application board, can
provide for software and hardware debugging using actual
production units.
6.0 Architectural Overview
6.1 EMI REDUCTION
The COP8AME9 device incorporates circuitry that guards
against electromagnetic interference - an increasing problem
in today’s microcontroller board designs. National’s patented
EMI reduction technology offers low EMI clock circuitry,
gradual turn-on output drivers (GTOs) and internal Icc
smoothing filters, to help circumvent many of the EMI issues
influencing embedded control designs. National has
achieved 15 dB–20 dB reduction in EMI transmissions when
designs have incorporated its patented EMI reducing circuitry.
6.5 ARCHITECTURE
The COP8 family is based on a modified Harvard architecture, which allows data tables to be accessed directly from
program memory. This is very important with modern
microcontroller-based applications, since program memory
is usually ROM, EPROM or Flash, while data memory is
usually RAM. Consequently constant data tables need to be
contained in non-volatile memory, so they are not lost when
the microcontroller is powered down. In a modified Harvard
architecture, instruction fetch and memory data transfers
can be overlapped with a two stage pipeline, which allows
the next instruction to be fetched from program memory
while the current instruction is being executed using data
memory. This is not possible with a Von Neumann singleaddress bus architecture.
6.2 IN-SYSTEM PROGRAMMING AND VIRTUAL
EEPROM
The device includes a program in a boot ROM that provides
the capability, through the MICROWIRE/PLUS serial interface, to erase, program and read the contents of the Flash
memory.
Additional routines are included in the boot ROM, which can
be called by the user program, to enable the user to customize in-system software update capability if MICROWIRE/
PLUS is not desired.
Additional functions will copy blocks of data between the
RAM and the Flash Memory. These functions provide a
virtual EEPROM capability by allowing the user to emulate a
variable amount of EEPROM by initializing nonvolatile variables from the Flash Memory and occasionally restoring
these variables to the Flash Memory.
The contents of the boot ROM have been defined by National. Execution of code from the boot ROM is dependent
on the state of the FLEX bit in the Option Register on exit
from RESET. If the FLEX bit is a zero, the Flash Memory is
assumed to be empty and execution from the boot ROM
begins. For further information on the FLEX bit, refer to
Section 4.5, Option Register.
The COP8 family supports a software stack scheme that
allows the user to incorporate many subroutine calls. This
capability is important when using High Level Languages.
With a hardware stack, the user is limited to a small fixed
number of stack levels.
6.6 INSTRUCTION SET
In today’s 8-bit microcontroller application arena cost/
performance, flexibility and time to market are several of the
key issues that system designers face in attempting to build
well-engineered products that compete in the marketplace.
Many of these issues can be addressed through the manner
in which a microcontroller’s instruction set handles processing tasks. And that’s why the COP8 family offers a unique
and code-efficient instruction set - one that provides the
flexibility, functionality, reduced costs and faster time to market that today’s microcontroller based products require.
Code efficiency is important because it enables designers to
pack more on-chip functionality into less program memory
space (ROM, OTP or Flash). Selecting a microcontroller with
less program memory size translates into lower system
costs, and the added security of knowing that more code can
be packed into the available program memory space.
6.3 DUAL CLOCK AND CLOCK DOUBLER
The device includes a versatile clocking system and two
oscillator circuits designed to drive a crystal or ceramic
resonator. The primary oscillator operates at high speed up
to 10 MHz.. The secondary oscillator is optimized for operation at 32.768 kHz.
The user can, through specified transition sequences
(please refer to Section 13.0 Power Saving Features), switch
execution between the high speed and low speed oscillators.
The unused oscillator can then be turned off to minimize
power dissipation. If the low speed oscillator is not used, the
pins are available as general purpose bidirectional ports.
The operation of the CPU will use a clock at twice the
frequency of the selected oscillator (up to 20 MHz for high
speed operation and 65.536 kHz for low speed operation).
This doubled clock will be referred to in this document as
‘MCLK’. The frequency of the selected oscillator will be
referred to as CKI. Instruction execution occurs at one tenth
the selected MCLK rate.
6.6.1 Key Instruction Set Features
The COP8 family incorporates a unique combination of instruction set features, which provide designers with optimum
code efficiency and program memory utilization.
6.6.2 Single Byte/Single Cycle Code Execution
The efficiency is due to the fact that the majority of instructions are of the single byte variety, resulting in minimum
program space. Because compact code does not occupy a
substantial amount of program memory space, designers
can integrate additional features and functionality into the
microcontroller program memory space. Also, the majority
instructions executed by the device are single cycle, resulting in minimum program execution time. In fact, 77% of the
instructions are single byte single cycle, providing greater
code and I/O efficiency, and faster code execution.
6.4 TRUE IN-SYSTEM EMULATION
On-chip emulation capability has been added, which allows
the user to perform true in-system emulation using final
production boards and devices. This simplifies testing and
evaluation of software in real environmental conditions. The
user, merely by providing for a standard connector which can
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6.6.3 Many Single-Byte, Multi-Function Instructions
The COP8 instruction set utilizes many single-byte, multifunction instructions. This enables a single instruction to
accomplish multiple functions, such as DRSZ, DCOR, JID,
LD (Load) and X (Exchange) instructions with postincrementing and post-decrementing, to name just a few
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ability to set, reset and test any individual bit in the data
memory address space, including memory-mapped I/O ports
and associated registers.
(Continued)
examples. In many cases, the instruction set can simultaneously execute as many as three functions with the same
single-byte instruction.
JID: (Jump Indirect); Single byte instruction decodes external events and jumps to corresponding service routines
(analogous to “DO CASE” statements in higher level languages).
LAID: (Load Accumulator-Indirect); Single byte look up table
instruction provides efficient data path from the program
memory to the CPU. This instruction can be used for table
lookup and to read the entire program memory for checksum
calculations.
6.6.5 Register Set
Three memory-mapped pointers handle register indirect addressing and software stack pointer functions. The memory
data pointers allow the option of post-incrementing or postdecrementing with the data movement instructions (LOAD/
EXCHANGE). And 15 memory-mapped registers allow designers to optimize the precise implementation of certain
specific instructions.
6.7 PACKAGING/PIN EFFICIENCY
Real estate and board configuration considerations demand
maximum space and pin efficiency, particularly given today’s
high integration and small product form factors. Microcontroller users try to avoid using large packages to get the I/O
needed. Large packages take valuable board space and
increases device cost, two trade-offs that microcontroller
designs can ill afford.
RETSK: (Return Skip); Single byte instruction allows return
from subroutine and skips next instruction. Decision to
branch can be made in the subroutine itself, saving code.
AUTOINC/DEC: (Auto-Increment/Auto-Decrement); These
instructions use the two memory pointers B and X to efficiently process a block of data (simplifying “FOR NEXT” or
other loop structures in higher level languages).
The COP8 family offers a wide range of packages and does
not waste pins: up to 85.7% are devoted to useful I/O.
6.6.4 Bit-Level Control
Bit-level control over many of the microcontroller’s I/O ports
provides a flexible means to ease layout concerns and save
board space. All members of the COP8 family provide the
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COP8AME9
6.0 Architectural Overview
COP8AME9
7.0 Absolute Maximum Ratings (Note
Total Current out of GND Pin (Sink)
1)
Storage Temperature Range
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
ESD Protection Level
Supply Voltage (VCC)
Voltage at Any Pin
−65˚C to +140˚C
2 kV (Human Body
Model)
Note 1: Absolute maximum ratings indicate limits beyond which damage to
the device may occur. DC and AC electrical specifications are not ensured
when operating the device at absolute maximum ratings.
7V
−0.3V to VCC +0.3V
Total Current into VCC Pin (Source)
200 mA
200 mA
8.0 Electrical Characteristics
DC Electrical Characteristics (−40˚C ≤ TA ≤ +85˚C)
Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis.
Parameter
Conditions
Min
Typ
Max
Units
Operating Voltage
4.5
5.5
V
Power Supply Rise Time
10
50 x 106
ns
0.1 VCC
V
Power Supply Ripple (Note 2)
Peak-to-Peak
Supply Current on VCC pin(Note 3)
High Speed Mode
CKI = 10 MHz
VCC = 5.5V, tC = 0.5 µs
14.5
mA
CKI = 3.33 MHz
VCC = 4.5V, tC = 1.5 µs
7
mA
CKI = 10 MHz, Low Speed OSC = 32 kHz
VCC = 5.5V, tC = 0.5 µs
14.5
mA
CKI = 3.33 MHz, Low Speed OSC = 32 kHz
VCC = 4.5V, tC = 1.5 µs
7
mA
Dual Clock Mode
Low Speed Mode
Low Speed OSC = 32 kHz
VCC = 5.5V
60
103
µA
High Speed Mode
VCC = 5.5V, CKI = 0 MHz
<1
10
µA
Dual Clock Mode
VCC = 5.5V, CKI = 0 MHz,
Low Speed OSC = 32 kHz
<5
17
µA
Low Speed Mode
VCC = 5.5V, CKI = 0 MHz,
Low Speed OSC = 32 kHz
<5
17
µA
HALT Current with BOR Disabled (Test Mode
only)(Note 4)
Idle Current on VCC pin (Note 3)
High Speed Mode
CKI = 10 MHz
VCC = 5.5V, tC = 0.5 µs
2.5
mA
CKI = 3.33 MHz
VCC = 4.5V, tC = 1.5 µs
1.2
mA
CKI = 10 MHz, Low Speed OSC = 32 kHz
VCC = 5.5V, tC = 0.5 µs
2.5
mA
CKI = 3.33 MHz, Low Speed OSC = 32 kHz
VCC = 4.5V, tC = 1.5 µs
1.2
mA
Dual Clock Mode
Low Speed Mode
Low Speed OSC = 32 kHz
VCC = 5.5V
Supply Current for BOR Feature
VCC = 5.5V
Brownout Trip Level
15
4.17
4.28
30
µA
45
µA
4.5
V
Input Levels (VIH, VIL)
Logic High
0.8 VCC
V
Logic Low
Internal Bias Resistor for the CKI
Crystal/Resonator Oscillator
0.3
1.0
0.16 VCC
V
2.5
MΩ
Hi-Z Input Leakage
VCC = 5.5V
−0.5
+0.5
µA
Input Pullup Current
VCC = 5.5V, VIN = 0V
−50
−210
µA
Port Input Hysteresis
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0.25 VCC
10
V
COP8AME9
8.0 Electrical Characteristics
(Continued)
DC Electrical Characteristics (−40˚C ≤ TA ≤ +85˚C)
(Continued)
Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis.
Parameter
Conditions
Min
Typ
Max
Units
Output Current Levels
Source (Weak Pull-Up Mode)
VCC = 4.5V, VOH = 3.8V
−10
Source (Push-Pull Mode)
VCC = 4.5V, VOH = 3.8V
−7
mA
Sink (Push-Pull Mode) (Note 7)
VCC = 4.5V, VOL = 1.0V
10
mA
µA
Allowable Sink Current per Pin
TRI-STATE Leakage
VCC = 5.5V
15
mA
+0.5
µA
± 200
mA
7
pF
VCC + 7
V
−0.5
Maximum Input Current without Latchup (Note 5)
RAM Retention Voltage, VR (in HALT Mode)
2.0
V
Input Capacitance
Voltage on G6 to force execution from Boot ROM
(Note 8)
G6 rise time must be
slower than 100 ns
2 x VCC
G6 Rise Time to force execution from Boot ROM
Input Current on G6 when Input > VCC
100
nS
VIN = 11V, VCC = 5.5V
Flash Endurance
Flash Data Retention
25˚C
500
µA
100k
cycles
100
years
AC Electrical Characteristics (−40˚C ≤ TA ≤ +85˚C)
Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis.
Parameter
Conditions
Min
4.5V ≤ VCC ≤ 5.5V
0.5
Typ
Max
Units
DC
µs
2
MHz
Instruction Cycle Time (tC)
Crystal/Resonator
Frequency of MICROWIRE/PLUS in
Slave Mode
MICROWIRE/PLUS Setup Time (tUWS)
20
ns
MICROWIRE/PLUS Hold Time (tUWH)
20
ns
MICROWIRE/PLUS Output Propagation
Delay (tUPD)
150
ns
Input Pulse Width
Interrupt Input High Time
1
tC
Interrupt Input Low Time
1
tC
Timer 1 Input High Time
1
tC
Timer 1 Input Low Time
1
tC
Timer 2, 3 Input High Time (Note 6)
1
MCLK or tC
Timer 2, 3 Input Low Time (Note 6)
1
MCLK or tC
Timer 2, 3 Output High Time
150
ns
Timer 2, 3 Output Low Time
150
ns
Output Pulse Width
USART Bit Time when using External
CKX
6 CKI
periods
USART CKX Frequency when being
Driven by Internal Baud Rate Generator
2
Reset Pulse Width
Flash Memory Mass Erase Time
Flash Memory Page Erase Time
See Table 13, Typical
Flash Memory
Endurance
MHz
0.5
µs
8
ms
1
ms
tC = instruction cycle time.
Note 2: Maximum rate of voltage change must be < 0.5 V/ms.
11
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COP8AME9
AC Electrical Characteristics (−40˚C ≤ TA ≤ +85˚C)
(Continued)
Note 3: Supply and IDLE currents are measured with CKI driven with a square wave Oscillator, CKO driven 180˚ out of phase with CKI, inputs connected to VCC
and outputs driven low but not connected to a load.
Note 4: The HALT mode will stop CKI from oscillating. Measurement of IDD HALT is done with device neither sourcing nor sinking current; with L, B, G0, and G2–G5
programmed as low outputs and not driving a load; all inputs tied to VCC; A/D converter and clock monitor and BOR disabled. Parameter refers to HALT mode
entered via setting bit 7 of the G Port data register.
Note 5: Pins G6 and RESET are designed with a high voltage input network. These pins allow input voltages > VCC and the pins will have sink current to VCC when
biased at voltages > VCC(the pins do not have source current when biased at a voltage below VCC). These two pins will not latch up. The voltage at these pins must
be limited to < (VCC+ 7V). WARNING: Voltages in excess of (VCC + 7V) will cause damage to these pins. This warning excludes ESD transients.
Note 6: If timer is in high speed mode, the minimum time is 1 MCLK. If timer is not in high speed mode, the minimum time is 1 tC.
Note 7: Absolute Maximum Ratings should not be exceeded.
Note 8: Vcc must be valid and stable before G6 is raised to a high voltage.
A/D Converter Electrical Characteristics (−20˚C ≤ TA ≤ +85˚C)
(Single-ended mode only)
Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis.
Parameter
Conditions
Min
Typ
Resolution
DNL
VCC = 5V
INL
VCC = 5V
Offset Error
VCC = 5V
Gain Error
VCC = 5V
Input Voltage Range
4.5V ≤ VCC ≤ 5.5V
0
Max
Units
10
Bits
±1
± 2.5
± 1.5
LSB
+0.5/-2.0
LSB
LSB
LSB
VCC
V
Analog Input Leakage Current
0.5
µA
Analog Input Resistance (Note 9)
6k
Ω
7
pF
Analog Input Capacitance
Conversion Clock Period
4.5V ≤ VCC ≤ 5.5V
0.8
Conversion Time (Including S/H Time)
Operating Current on AVCC
15
AVCC = 5.5V
0.2
Note 9: Resistance between the device input and the internal sample and hold capacitance.
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30
12
µs
A/D
Conversion
Clock
Cycles
0.6
mA
Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis.
Parameter
Conditions
Min
Input Offset Voltage
Typ
-7
Input Common Mode Capacitance
Max
Units
+7
mV
10
Common Mode Rejection Ratio
(CMRR)
0V ≤ VCM ≤ VCC
Power Supply Rejection Ratio
(PSRR)
VCM = VCC/2
Common Mode Voltage Range
(CMVR)
CMRR ≥ 45dB
Large Signal Voltage Gain
RL = 2k to VCC/2,
VCM = VCC/2
0.5 ≤ VO ≤ VCC - 0.5V
pF
50
dB
70
dB
VCC + 0.2
-0.2
Output Swing High
RL = 2k to VCC/2,
Vid = 100 mV
Output Swing Low
RL = 2k to VCC/2,
Vid = 100 mV
70
V
85
dB
VCC - 70
mV
80
mV
Output Short Circuit Current (Note VO = GND,
10)
Vid = 100 mV
20
mA
Output Short Circuit Current (Note VO = VCC,
Vid = 100 mV
10)
15
mA
Supply Current on AVCC when
enabled
AVCC = 5.5 V,
No Load
500
µA
Enable Time
15
µS
Disable Time
1
µS
Slew Rate (Note 11)
Unity Gain Frequency
315
Gain = 1, RL = 10k,
CL < 350 pF
Vin = 2V square wave
1.0
RL = 2k to VCC/2
1.5
V/µS
2.0
Mhz
Input Referred Voltage Noise
55
Total Harmonic Distortion (THD)
f = 1kHz, AV = 1, Vo = 2.2 Vpp,
RL = 600Ω to VCC/2
0.2
%
Note 10: Short circuit test is a momentary test. Extended period output short circuit may damage the device.
Note 11: Slew rate is the slower of the rising and falling slew rates.
Programmable Gain Amplifier Electrical Characteristics (4.5V ≤ AVCC ≤
5.5V, −40˚C ≤ TA ≤ +85˚C)
Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis.
Parameter
Conditions
Input Offset Voltage Untrimmed
Input Offset Voltage Trimmed
Min
Max
Units
-7
Typ
+7
mV
−0.5
−0.5
mV
Common Mode Rejection Ratio
Untrimmed (CMRR)
0V ≤ VCM ≤ VCC
50
dB
Common Mode Rejection Ratio
Trimmed (CMRR)
0V ≤ VCM ≤ VCC
70
dB
VCM = VCC/2
70
dB
VIN = VCC,
Gain = 1
VCC - 8
mV
Power Supply Rejection Ratio
(PSRR)
Output Swing High
13
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COP8AME9
Stand-alone Amplifier Electrical Characteristics (4.5V ≤ AVCC ≤ 5.5V, −40˚C
≤ TA ≤ +85˚C)
COP8AME9
Programmable Gain Amplifier Electrical Characteristics (4.5V ≤ AVCC ≤
5.5V, −40˚C ≤ TA ≤ +85˚C) (Continued)
Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis.
Parameter
Max
Units
0.7
mV
500
µA
Enable Time
40
µS
Disable Time
1
µS
Output Swing Low
Supply Current on AVCC when
enabled
Slew Rate (Note 11)
Programmable Gain Tolerance
(Trimmed)
Conditions
Min
Typ
VIN = 0,
Gain = 1
AVCC = 5.5V
315
See Table in A/D Section for conditions
that are slew rate limited
1.0
1.5
V/µS
±1
±2
Gain = 1,2,5,
Gain = 10, 20, 49, 98
%
%
Temperature Sensor Electrical Characteristics (−40˚C ≤ TA ≤ +85˚C)
Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis.
Parameter
Output Voltage at 0˚C
Conditions
Min
2.7V ≤ AVCC ≤ 5.5V
Deviation from Equation
-12
Line Regulation
Max
AVCC = 5.5V
+12
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14
˚C
mV/V
350
µS
300
µA
20006305
FIGURE 1. MICROWIRE/PLUS Timing
Units
V
TBD
Enable time
Quiescent Current on AVCC when
enabled
Typ
1.65
The COP8AME9 I/O structure enables designers to reconfigure the microcontroller’s I/O functions with a single instruction. Each individual I/O pin can be independently configured as output pin low, output high, input with high
impedance or input with weak pull-up device. A typical example is the use of I/O pins as the keyboard matrix input
lines. The input lines can be programmed with internal weak
pull-ups so that the input lines read logic high when the keys
are all open. With a key closure, the corresponding input line
will read a logic zero since the weak pull-up can easily be
overdriven. When the key is released, the internal weak
pull-up will pull the input line back to logic high. This eliminates the need for external pull-up resistors. The high current options are available for driving LEDs, motors and
speakers. This flexibility helps to ensure a cleaner design,
with less external components and lower costs. Below is the
general description of all available pins.
VCC and GND are the power supply pins. All VCC and GND
pins must be connected.
B4 Analog Channel 12 or AMP1 − Input
B3 Analog Channel 11 or AMP1 Output
B2 Analog Channel 10
Port G is an 8-bit port. Pin G0, G2–G5 are bi-directional I/O
ports. Pin G6 is always a general purpose Hi-Z input. All pins
have Schmitt Triggers on their inputs. Pin G1 serves as the
dedicated WATCHDOG output with weak pull-up if the
WATCHDOG feature is selected by the Option register.
The pin is a general purpose I/O if WATCHDOG feature is
not selected. If WATCHDOG feature is selected, bit 1 of the
Port G configuration and data register does not have any
effect on Pin G1 setup.
G7 serves as the dedicated output pin for the CKO clock
output.
There are two registers associated with the G Port, a data
register and a configuration register. Therefore, each of the 6
I/O bits (G0 - G5) can be individually configured under
software control.
Since G6 is an input only pin and G7 is the dedicated CKO
clock output pin, the associated bits in the data and configuration registers for G6 and G7 are used for special purpose
functions as outlined below. Reading the G6 and G7 data
bits will return zeros.
The chip is placed in the HALT mode by writing a "1" to bit 7
of the Port G Data register. Similarly the chip will be placed
in the IDLE mode by writing a "1" to bit 6 of the Port G Data
Register.
Writing a “1” to bit 6 of the Port G Configuration Register
enables the MICROWIRE/PLUS to operate with the alternate phase of the SK clock.
CKI is the clock input. This can be connected (in conjunction
with CKO) to an external crystal circuit to form a crystal
oscillator. See Oscillator Description section.
RESET is the master reset input. See Reset description
section.
AVCC is the Analog Supply for A/D converter. It should be
connected to VCC externally.
AGND is the ground pin for the A/D converter. It should be
connected to GND externally.
The device contains up to three bidirectional 8-bit I/O ports
(B, G and L) where each individual IO may be independently
configured as an input (Schmitt trigger inputs on ports L and
G), output or TRI-STATE under program control. Three data
memory address locations are allocated for each of these
I/O ports. Each I/O port has three associated 8-bit memory
mapped registers, the CONFIGURATION register, the output
DATA register and the Pin input register. (See the memory
map for the various addresses associated with the I/O ports.)
Figure 2 shows the I/O port configurations. The DATA and
CONFIGURATION registers allow for each port bit to be
individually configured under software control as shown below:
CONFIGURATION
Register
DATA
Register
0
0
Config. Reg.
Hi-Z Input
(TRI-STATE Output)
1
Input with Weak Pull-Up
1
0
Push-Pull Zero Output
1
1
Push-Pull One Output
Not Used
HALT
G6
Alternate SK
IDLE
Port G has the following alternate features:
G7 CKO Oscillator dedicated output
G6 SI (MICROWIRE/PLUS Serial Data Input)
G5 SK (MICROWIRE/PLUS Serial Clock)
G4 SO (MICROWIRE/PLUS Serial Data Output)
G3 T1A (Timer T1 I/O)
G2 T1B (Timer T1 Capture Input)
G1 WDOUT WATCHDOG and/or Clock Monitor if WATCHDOG enabled, otherwise it is a general purpose I/O
G0 INTR (External Interrupt Input)
Port Set-Up
0
Data Reg.
G7
G0 through G3 are also used for In-System Emulation.
Port L is an 8-bit I/O port. All L-pins have Schmitt triggers on
the inputs.
Port L supports the Multi-Input Wake-Up feature on all eight
pins. Port L has the following alternate pin functions:
L7 Multi-Input Wake-up or T3B (Timer T3B Input)
L6 Multi-Input Wake-up or T3A (Timer T3A Input/Output)
L5 Multi-Input Wake-up or T2B (Timer T2B Input)
L4 Multi-Input Wake-up or T2A (Timer T2A Input/Output)
L3 Multi-Input Wake-up and/or RDX (USART Receive)
L2 Multi-Input Wake-up or TDX (USART Transmit)
L1 Multi-Input Wake-up and/or CKX (USART Clock) (Low
Port B is a 6-bit I/O port. All B pins have Schmitt triggers on
the inputs. The 28-pin packages do not have a full 8-bit port
and contain some unbonded, floating pads internally on the
chip. The binary value read from these bits is undetermined.
The application software should mask out these unknown
bits when reading the Port B register, or use only bit-access
program instructions when accessing Port B. These unconnected bits draw power only when they are addressed (i.e.,
in brief spikes). Additionally, if Port B is being used with some
combination of digital inputs and analog inputs, the analog
inputs will read as undetermined values and should be
masked out by software.
Port B supports the analog inputs for the A/D converter. Port
B has the following alternate pin functions:
15
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COP8AME9
B7 Analog Channel 15 or A/D Input
B6 Analog Channel 14 or Analog Multiplexor Output
B5 Analog Channel 13 or AMP1 + Input
9.0 Pin Descriptions
COP8AME9
9.0 Pin Descriptions
nector can be designed into the production PC board and
can be replaced by jumpers or signal traces when emulation
is no longer necessary.
(Continued)
Speed Oscillator Output)
L0 Multi-Input Wake-up (Low Speed Oscillator Input)
The emulator will replicate all functions of G0 - G3 and
Reset. For proper operation, no connection should be made
on the device side of the emulator connector.
20006306
FIGURE 2. I/O Port Configurations
20006309
FIGURE 5. Emulation Connection
10.0 Functional Description
The architecture of the device is a modified Harvard architecture. With the Harvard architecture, the program memory
(Flash) is separate from the data store memory (RAM). Both
Program Memory and Data Memory have their own separate
addressing space with separate address buses. The architecture, though based on the Harvard architecture, permits
transfer of data from Flash Memory to RAM.
20006307
FIGURE 3. I/O Port Configurations — Output Mode
10.1 CPU REGISTERS
The CPU can do an 8-bit addition, subtraction, logical or shift
operation in one instruction (tC) cycle time.
There are six CPU registers:
A is the 8-bit Accumulator Register
PC is the 15-bit Program Counter Register
PU is the upper 7 bits of the program counter (PC)
PL is the lower 8 bits of the program counter (PC)
B is an 8-bit RAM address pointer, which can be optionally
post auto incremented or decremented.
X is an 8-bit alternate RAM address pointer, which can be
optionally post auto incremented or decremented.
S is the 8-bit Data Segment Address Register used to extend
the lower half of the address range (00 to 7F) into 256 data
segments of 128 bytes each.
SP is the 8-bit stack pointer, which points to the subroutine/
interrupt stack (in RAM). With reset the SP is initialized to
RAM address 06F Hex. The SP is decremented as items are
pushed onto the stack. SP points to the next available location on the stack.
All the CPU registers are memory mapped with the exception of the Accumulator (A) and the Program Counter (PC).
20006308
FIGURE 4. I/O Port Configurations — Input Mode
9.1 EMULATION CONNECTION
Connection to the emulation system is made via a 2 x 7
connector which interrupts the continuity of the RESET, G0,
G1, G2 and G3 signals between the COP8 device and the
rest of the target system (as shown in Figure 5). This con-
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16
If a Return instruction is executed when the SP contains 6F
(hex), instruction execution will continue from Program
Memory location 1FFF (hex). If location 1FFF is accessed by
an instruction fetch, the Flash Memory will return a value of
00. This is the opcode for the INTR instruction and will cause
a Software Trap.
(Continued)
10.2 PROGRAM MEMORY
The program memory consists of 8192 bytes of Flash
Memory. These bytes may hold program instructions or constant data (data tables for the LAID instruction, jump vectors
for the JID instruction, and interrupt vectors for the VIS
instruction). The program memory is addressed by the 15-bit
program counter (PC). All interrupts in the device vector to
program memory location 00FF Hex. The contents of the
program memory read 00 Hex in the erased state. Program
execution starts at location 0 after RESET.
For the purpose of erasing and rewriting the Flash Memory,
it is organized in pages of 64 bytes.
Refer to Table 1 for program memory size and available
address ranges.
TABLE 1. Available Memory Address Ranges
Device
Program
Memory
Size (Flash)
COP8AME9
8192
Flash Memory
Option Register
Page Size
Address (Hex)
(Bytes)
64
1FFF
10.3 DATA MEMORY
The data memory address space includes the on-chip RAM
and data registers, the I/O registers (Configuration, Data and
Pin), the control registers, the MICROWIRE/PLUS SIO shift
register, and the various registers, and counters associated
with the timers and the USART (with the exception of the
IDLE timer). Data memory is addressed directly by the instruction or indirectly by the B, X and SP pointers.
The data memory consists of 512 bytes of RAM. Sixteen
bytes of RAM are mapped as “registers” at addresses 0F0 to
0FF Hex. These registers can be loaded immediately, and
also decremented and tested with the DRSZ (decrement
register and skip if zero) instruction. The memory pointer
registers X, SP, B and S are memory mapped into this space
at address locations 0FC to 0FF Hex respectively, with the
other registers being available for general usage.
The instruction set permits any bit in memory to be set, reset
or tested. All I/O and registers (except A and PC) are
memory mapped; therefore, I/O bits and register bits can be
directly and individually set, reset and tested. The accumulator (A) bits can also be directly and individually tested.
Note: RAM contents are undefined upon power-up.
Data Memory
Size (RAM)
Segments
Available
Maximum
RAM
Address
(HEX)
512
0-3
037F
0000 to 007F) from XX00 to XX7F, where XX represents the
8 bits from the S register. Thus the 128-byte data segment
extensions are located from addresses 0100 to 017F for
data segment 1, 0200 to 027F for data segment 2, etc., up to
FF00 to FF7F for data segment 255. The base address
range from 0000 to 007F represents data segment 0. Refer
to Table 1 to determine available RAM segments for this
device.
Figure 6 illustrates how the S register data memory extension is used in extending the lower half of the base address
range (00 to 7F hex) into 256 data segments of 128 bytes
each, with a total addressing range of 32 kbytes from XX00
to XX7F. This organization allows a total of 256 data segments of 128 bytes each with an additional upper base
segment of 128 bytes. Furthermore, all addressing modes
are available for all data segments. The S register must be
changed under program control to move from one data
segment (128 bytes) to another. However, the upper base
segment (containing the 16 memory registers, I/O registers,
control registers, etc.) is always available regardless of the
contents of the S register, since the upper base segment
(address range 0080 to 00FF) is independent of data segment extension.
The instructions that utilize the stack pointer (SP) always
reference the stack as part of the base segment (Segment
0), regardless of the contents of the S register. The S register
is not changed by these instructions. Consequently, the
stack (used with subroutine linkage and interrupts) is always
located in the base segment. The stack pointer will be initialized to point at data memory location 006F as a result of
reset.
The 128 bytes of RAM contained in the base segment are
split between the lower and upper base segments. The first
112 bytes of RAM are resident from address 0000 to 006F in
the lower base segment, while the remaining 16 bytes of
RAM represent the 16 data memory registers located at
addresses 00F0 to 00FF of the upper base segment. No
RAM is located at the upper sixteen addresses (0070 to
007F) of the lower base segment.
Additional RAM beyond these initial 128 bytes, however, will
always be memory mapped in groups of 128 bytes (or less)
at the data segment address extensions (XX00 to XX7F) of
the lower base segment.
10.4 DATA MEMORY SEGMENT RAM EXTENSION
Data memory address 0FF is used as a memory mapped
location for the Data Segment Address Register (S).
The data store memory is either addressed directly by a
single byte address within the instruction, or indirectly relative to the reference of the B, X, or SP pointers (each
contains a single-byte address). This single-byte address
allows an addressing range of 256 locations from 00 to FF
hex. The upper bit of this single-byte address divides the
data store memory into two separate sections as outlined
previously. With the exception of the RAM register memory
from address locations 00F0 to 00FF, all RAM memory is
memory mapped with the upper bit of the single-byte address being equal to zero. This allows the upper bit of the
single-byte address to determine whether or not the base
address range (from 0000 to 00FF) is extended. If this upper
bit equals one (representing address range 0080 to 00FF),
then address extension does not take place. Alternatively, if
this upper bit equals zero, then the data segment extension
register S is used to extend the base address range (from
17
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COP8AME9
10.0 Functional Description
COP8AME9
10.0 Functional Description
(Continued)
20006361
FIGURE 6. RAM Organization
=0
Security disabled. Flash Memory read and write
are allowed.
Bits 4, 3 These bits are reserved and must be 0.
Bit 2
=1
WATCHDOG feature disabled. G1 is a general
purpose I/O.
=0
WATCHDOG feature enabled. G1 pin is
WATCHDOG output with weak pullup.
Bit 1
=1
HALT mode disabled.
=0
HALT mode enabled.
Bit 0
=1
Execution following RESET will be from Flash
Memory.
=0
Flash Memory is erased. Execution following RESET will be from Boot ROM with the MICROWIRE/
PLUS ISP routines.
10.4.1 Virtual EEPROM
The Flash memory and the User ISP functions (see Section
5.7), provide the user with the capability to use the flash
program memory to back up user defined sections of RAM.
This effectively provides the user with the same nonvolatile
data storage as EEPROM. Management, and even the
amount of memory used, are the responsibility of the user,
however the flash memory read and write functions have
been provided in the boot ROM.
One typical method of using the Virtual EEPROM feature
would be for the user to copy the data to RAM during system
initialization, periodically, and if necessary, erase the page of
Flash and copy the contents of the RAM back to the Flash.
10.5 OPTION REGISTER
The Option register, located at address 0x1FFF in the Flash
Program Memory, is used to configure the user selectable
security, WATCHDOG, and HALT options. The register can
be programmed only in external Flash Memory programming
or ISP Programming modes. Therefore, the register must be
programmed at the same time as the program memory. The
contents of the Option register shipped from the factory read
00 Hex.
The format of the Option register is as follows:
Bit 7
Bit 6
Reserved
Bit 5
SECURITY
Bit 4
Bit 3
Reserved
Bit 2
Bit 1
Bit 0
WATCH
DOG
HALT
FLEX
The COP8 assembler defines a special ROM section type,
CONF, into which the Option Register data may be coded.
The Option Register is programmed automatically by programmers that are certified by National.
The user needs to ensure that the FLEX bit will be set when
the device is programmed.
The following examples illustrate the declaration of the Option Register.
Syntax:
[label:].sect
config, conf
.db
value
;1 byte,
;configures
Bits 7, 6 These bits are reserved and must be 0.
Bit 5
=1
Security enabled. Flash Memory read and write
are not allowed except in User ISP/Virtual E2 commands. Mass Erase is allowed.
www.national.com
18
10.7 RESET
The device is initialized when the RESET pin is pulled low or
the On-chip Brownout Reset is activated.
(Continued)
;options
.endsect
Example: The following sets a value in the Option Register
for a COP8AME9. The Option Register bit values shown
select options: Security disabled, WATCHDOG enabled
HALT mode enabled and execution will commence from
Flash Memory.
.chip
8AME
.sect
option, conf
.db
0x01
;wd, halt, flex
.endsect
...
.end
start
Note: All programmers certified for programming this family
of parts will support programming of the Option Register.
Please contact National or your device programmer supplier
for more information.
20006311
FIGURE 7. Reset Logic
The following occurs upon initialization:
Port B: TRI-STATE (High Impedance Input)
Port G: TRI-STATE (High Impedance Input). Exceptions: If
Watchdog is enabled, then G1 is Watchdog output. G0 and
G2 have their weak pull-up enabled during RESET.
Port L: TRI-STATE (High Impedance Input)
PC: CLEARED to 0000
10.6 SECURITY
The device has a security feature which, when enabled,
prevents external reading of the Flash program memory. The
security bit in the Option Register determines, whether security is enabled or disabled. If the security feature is disabled, the contents of the internal Flash Memory may be
read by external programmers or by the built in
MICROWIRE/PLUS serial interface ISP. Security must be
enforced by the user when the contents of the Flash
Memory are accessed via the user ISP or Virtual EEPROM capability.
If the security feature is enabled, then any attempt to externally read the contents of the Flash Memory will result in the
value FF (hex) being read from all program locations (except
the Option Register). In addition, with the security feature
enabled, the write operation to the Flash program memory
and Option Register is inhibited. Page Erases are also inhibited when the security feature is enabled. The Option Register is readable regardless of the state of the security bit by
accessing location FFFF (hex). Mass Erase Operations are
possible regardless of the state of the security bit.
The security bit can be erased only by a Mass Erase of the
entire contents of the Flash unless Flash operation is under
the control of User ISP functions.
Note: The actual memory address of the Option Register is
1FFF (hex), however the MICROWIRE/PLUS ISP routines
require the address FFFF (hex) to be used to read the
Option Register when the Flash Memory is secured.
The entire Option Register must be programmed at one time
and cannot be rewritten without first erasing the entire last
page of Flash Memory.
PSW, CNTRL and ICNTRL registers: CLEARED
SIOR:
UNAFFECTED after RESET with power already applied
RANDOM after RESET at power-on
T2CNTRL: CLEARED
T3CNTRL: CLEARED
HSTCR: CLEARED
ITMR: Cleared except Bit 6 (HSON) = 1
Accumulator, Timer 1, Timer 2 and Timer 3:
RANDOM after RESET
WKEN, WKEDG: CLEARED
WKPND: RANDOM
SP (Stack Pointer):
Initialized to RAM address 06F Hex
B and X Pointers:
UNAFFECTED after RESET with power already applied
RANDOM after RESET at power-on
S Register: CLEARED
RAM:
UNAFFECTED after RESET with power already applied
RANDOM after RESET at power-on
USART:
PSR, ENU, ENUR, ENUI: Cleared, except the TBMT bit
which is set to one.
ANALOG TO DIGITAL CONVERTER:
ENAD: CLEARED
ADRSTH: RANDOM
ADRSTL: RANDOM
Op Amp:
AMPTRMN, AMPTRMP: Cleared, except bit 6 = 1
ADGAIN: CLEARED
ISP CONTROL:
ISPADLO: CLEARED
ISPADHI: CLEARED
PGMTIM: PRESET TO VALUE FOR 10 MHz CKI
19
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COP8AME9
10.0 Functional Description
COP8AME9
10.0 Functional Description
normally. If, however, VCC drops below Vbor, an internal reset
is generated, and the Idle Timer is preset with 00Fx. The
device now waits until VCC is greater than Vbor and the
countdown starts over. The functional operation of the device
is guaranteed down to the Vbor level.
(Continued)
WATCHDOG (if enabled):
The device comes out of reset with both the WATCHDOG
logic and the Clock Monitor detector armed, with the
WATCHDOG service window bits set and the Clock Monitor bit set. The WATCHDOG and Clock Monitor circuits
are inhibited during reset. The WATCHDOG service window bits being initialized high default to the maximum
WATCHDOG service window of 64k T0 clock cycles. The
Clock Monitor bit being initialized high will cause a Clock
Monitor error following reset if the clock has not reached
the minimum specified frequency at the termination of
reset. A Clock Monitor error will cause an active low error
output on pin G1. This error output will continue until
16–32 T0 clock cycles following the clock frequency
reaching the minimum specified value, at which time the
G1 output will go high.
One exception to the above is that the brownout circuit will
insert a delay of approximately 3 ms on power up or any time
the VCC drops below a voltage of about 1.8V. The device will
be held in Reset for the duration of this delay before the Idle
Timer starts counting the 240 to 256 tC. This delay starts as
soon as the VCC rises above the trigger voltage (approximately 1.8V). This behavior is shown in Figure 9.
In Case 1, VCC rises from 0V and the on-chip RESET is
undefined until the supply is greater than approximately
1.0V. At this time the brownout circuit becomes active and
holds the device in RESET. As the supply passes a level of
about 1.8V, a delay of about 3 ms (td) is started and the Idle
Timer is preset to a value between 00F0 and 00FF (hex).
Once VCC is greater than Vbor and td has expired, the Idle
Timer is allowed to count down (tid).
10.7.1 External Reset
Case 2 shows a subsequent dip in the supply voltage which
goes below the approximate 1.8V level. As VCC drops below
Vbor, the internal RESET signal is asserted. When VCC rises
back above the 1.8V level, td is started. Since the power
supply rise time is longer for this case, td has expired before
VCC rises above Vbor and tid starts immediately when VCC is
greater than Vbor.
Case 3 shows a dip in the supply where VCC drops below
Vbor, but not below 1.8V. On-chip RESET is asserted when
VCC goes below Vbor and tid starts as soon as the supply
goes back above Vbor.
The internal reset will not be turned off until the Idle Timer
underflows. The internal reset will perform the same functions as external reset. The device is guaranteed to operate
at the specified frequency down to the specified brownout
voltage. After the underflow, the logic is designed such that
no additional internal resets occur as long as VCC remains
above the brownout voltage.
The device is relatively immune to short duration negativegoing VCC transients (glitches). It is essential that good
filtering of VCC be done to ensure that the brownout feature
works correctly. Power supply decoupling is vital even in
battery powered systems.
Refer to the device specifications for the actual Vbor voltage.
Under no circumstances should the RESET pin be allowed
to float. If the external Reset feature is not being used, the
RESET pin should be connected directly to VCC. The RESET
input may also be connected to an external pull-up resistor
or to other external circuitry. The output of the brownout reset
detector will always preset the Idle Timer to a value between
00F0 and 00FF (240 to 256 tC). At this time, the internal reset
will be generated.
The contents of data registers and RAM are unknown following the on-chip reset.
The RESET input, when pulled low, initializes the device.
The RESET pin must be held low for a minimum of one
instruction cycle to guarantee a valid reset.
RESET may also be used to cause an exit from the HALT
mode.
A recommended reset circuit for this device is shown in
Figure 8.
20006312
FIGURE 8. Reset Circuit Using External Reset
10.7.2 On-Chip Brownout Reset
The device generates an internal reset as VCC rises. While
VCC is less than the specified brownout voltage (Vbor), the
device is held in the reset condition and the Idle Timer is
preset with 00Fx (240–256 tC). When VCC reaches a value
greater than Vbor, the Idle Timer starts counting down. Upon
underflow of the Idle Timer, the internal reset is released and
the device will start executing instructions. This internal reset
will perform the same functions as external reset. Once VCC
is above Vbor, and this initial Idle Timer time-out takes place,
instruction execution begins and the Idle Timer can be used
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20
COP8AME9
10.0 Functional Description
(Continued)
20006313
FIGURE 9. Brownout Reset Operation
count. The value of the resistor is in the range of 0.5M to 2M
(typically 1.0M). Table 2 shows the component values required for various standard crystal values. Resistor R2 is
on-chip, for the high speed oscillator, and is shown for
reference. Figure 11 shows the crystal oscillator connection
diagram. A ceramic resonator of the required frequency may
be used in place of a crystal if the accuracy requirements are
not quite as strict.
TABLE 2. Crystal Oscillator Configuration,
TA = 25˚C, VCC = 5V
20006314
FIGURE 10. Reset Circuit Using Power-On Reset
10.8 OSCILLATOR CIRCUITS
The device has two crystal oscillators to facilitate low power
operation while maintaining throughput when required. Further information on the use of the two oscillators is found in
Section 7.0 Power Saving Features. The low speed oscillator
utilizes the L0 and L1 port pins. References in the following
text to CKI will also apply to L0 and references to G7/CKO
will also apply to L1.
R1 (kΩ)
R2 (MΩ)
C1 (pF)
C2 (pF)
CKI Freq.
(MHz)
0
On Chip
18
18
10
0
On Chip
18
18
5
0
On Chip
18–36
18–36
1
5.6
On Chip
100
100–156
0.455
0
20
**
**
32.768
kHz*
*Applies to connection to low speed oscillator on port pins L0 and L1 only.
**See Note below.
10.8.1 Oscillator
CKI is the clock input while G7/CKO is the clock generator
output to the crystal. An on-chip bias resistor connected
between CKI and CKO is provided to reduce system part
21
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COP8AME9
10.0 Functional Description
TABLE 3. Startup Times
(Continued)
CKI Frequency
The crystal and other oscillator components should be
placed in close proximity to the CKI and CKO pins to minimize printed circuit trace length.
The values for the external capacitors should be chosen to
obtain the manufacturer’s specified load capacitance for the
crystal when combined with the parasitic capacitance of the
trace, socket, and package (which can vary from 0 to 8 pF).
The guideline in choosing these capacitors is:
Manufacturer’s specified load cap = (C1 * C2) / (C1 + C2) +
Cparasitic
C2 can be trimmed to obtain the desired frequency. C2
should be less than or equal to C1.
Startup Time
10 MHz
1–10 ms
3.33 MHz
3–10 ms
1 MHz
3–20 ms
455 kHz
10–30 ms
32 kHz (low speed oscillator)
2–5 sec
10.8.2 Clock Doubler
This device contains a frequency doubler that doubles the
frequency of the oscillator selected to operate the main
microcontroller core. The details of how to select either the
high speed oscillator or low speed oscillator are described in,
Power Saving Features. When the high speed oscillator
connected to CKI operates at 10 MHz, the internal clock
frequency is 20 MHz, resulting in an instruction cycle time of
0.5 µs. When the 32 kHz oscillator connected to L0 and L1 is
selected, the internal clock frequency is 64 kHz, resulting in
an instruction cycle of 152.6 µs. The output of the clock
doubler is called MCLK and is referenced in many places
within this document.
Note: The low power design of the low speed oscillator
makes it extremely sensitive to board layout and load capacitance. The user should place the crystal and load capacitors within 1cm. of the device and must ensure that the
above equation for load capacitance is strictly followed. If
these conditions are not met, the application may have
problems with startup of the low speed oscillator.
Low Speed Oscillator
High Speed Oscillator
20006316
20006315
FIGURE 11. Crystal Oscillator
10.9 CONTROL REGISTERS
10.9.2 PSW Register (Address X'00EF)
HC
10.9.1 CNTRL Register (Address X'00EE)
Bit 7
T1C3
T1C2
Bit 7
T1C1
T1C0
MSEL
IEDG
SL1
T1PNDA
T1ENA
EXPND
BUSY
EXEN
GIE
Bit 0
SL0
The PSW register contains the following select bits:
HC
Half Carry Flag
C
Carry Flag
T1PNDA Timer T1 Interrupt Pending Flag (Autoreload RA
in mode 1, T1 Underflow in Mode 2, T1A capture
edge in mode 3)
T1ENA Timer T1 Interrupt Enable for Timer Underflow
or T1A Input capture edge
EXPND External interrupt pending
BUSY
MICROWIRE/PLUS busy shifting flag
EXEN
Enable external interrupt
GIE
Global interrupt enable (enables interrupts)
Bit 0
The Timer1 (T1) and MICROWIRE/PLUS control register
contains the following bits:
T1C3
Timer T1 mode control bit
T1C2
Timer T1 mode control bit
T1C1
Timer T1 mode control bit
T1C0
Timer T1 Start/Stop control in timer
modes 1 and 2. T1 Underflow Interrupt
Pending Flag in timer mode 3
MSEL
Selects G5 and G4 as MICROWIRE/PLUS
signals SK and SO respectively
IEDG
External interrupt edge polarity select
(0 = Rising edge, 1 = Falling edge)
SL1 & SL0 Select the MICROWIRE/PLUS clock divide
by (00 = 2, 01 = 4, 1x = 8)
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C
The Half-Carry flag is also affected by all the instructions that
affect the Carry flag. The SC (Set Carry) and R/C (Reset
Carry) instructions will respectively set or clear both the carry
22
RA in mode 1, T3 Underflow in mode 2, T3A
capture edge in mode 3)
T3ENA
Timer T3 Interrupt Enable for Timer Underflow
or T3A Input capture edge
T3PNDB Timer T3 Interrupt Pending Flag for T3B capture edge
(Continued)
flags. In addition to the SC and R/C instructions, ADC,
SUBC, RRC and RLC instructions affect the Carry and Half
Carry flags.
T3ENB
10.9.3 ICNTRL Register (Address X'00E8)
Unused
LPEN
T0PND
T0EN
µWPND
µWEN
T1PNDB
T1ENB
Bit 7
10.9.6 HSTCR Register (Address X'00AF)
Bit 0
T2IDLE
The ICNTRL register contains the following bits:
LPEN
L
Port
Interrupt
Enable
(Multi-Input
Wake-up/Interrupt)
T0PND Timer T0 Interrupt pending
T2C1
T2C0
T2PNDA
T2ENA
T2PNDB
LSON
T2ENB
Bit 0
T3C2
T3C1
T3C0
T3PNDA
T3ENA
T3PNDB
DCEN
CCKS
EL
RSVD
ITSEL2
ITSEL1
ITSEL0
Bit 0
The ITMR register contains the following bits:
LSON
Turns the low speed oscillator on or off.
HSON
Turns the high speed oscillator on or off.
DCEN
Selects the high speed oscillator or the low
speed oscillator as the Idle Timer Clock.
CCKSEL Selects the high speed oscillator or the low
speed oscillator as the primary CPU clock.
RSVD
This bit is reserved and must be 0.
ITSEL2 Idle Timer period select bit.
ITSEL1 Idle Timer period select bit.
ITSEL0 Idle Timer period select bit.
10.9.8 ENAD Register (Address X'00CB)
ADCH3 ADCH2
ADCH1
Channel Select
Bit 7
ADCH0
ADMOD
Mode
Select
MUX
PSC
Mux Out Prescale
ADBSY
Busy
Bit 0
The ENAD
ADCH3
ADCH2
ADCH1
ADCH0
ADMOD
register contains the following bits:
ADC channel select bit
ADC channel select bit
ADC channel select bit
ADC channel select bit
Places the ADC in single-ended or differential
mode.
MUX
Enables the ADC multiplexor output.
PSC
Switches the ADC clock between a divide by one
or a divide by sixteen of MCLK.
ADBSY Signifies that the ADC is currently busy performing a conversion. When set by the user, starts a
conversion.
10.9.5 T3CNTRL Register (Address X'00B6)
T3C3
HSON
Bit 7
The T2CNTRL register contains the following bits:
T2C3
Timer T2 mode control bit
T2C2
Timer T2 mode control bit
T2C1
Timer T2 mode control bit
T2C0
Timer T2 Start/Stop control in timer
modes 1 and 2, Timer T2 Underflow Interrupt
Pending Flag in timer mode 3
T2PNDA Timer T2 Interrupt Pending Flag (Autoreload
RA in mode 1, T2 Underflow in mode 2, T2A
capture edge in mode 3)
T2ENA
Timer T2 Interrupt Enable for Timer Underflow
or T2A Input capture edge
T2PNDB Timer T2 Interrupt Pending Flag for T2B capture edge
T2ENB
Timer T2 Interrupt Enable for T2B Input capture
edge
Bit 7
Places Timer T3 in High Speed Mode.
Places Timer T2 in High Speed Mode.
10.9.7 ITMR Register (Address X'00CF)
Timer T1 Interrupt Enable for T1B Input capture
edge
T2C2
T2HS
Bit 0
T3HS
T2HS
10.9.4 T2CNTRL Register (Address X'00C6)
T2C3
T3HS
The HSTCR register contains the following bits:
T2IDLE Allows T2 to run while in Idle Mode.
µWEN
Enable MICROWIRE/PLUS interrupt
T1PNDB Timer T1 Interrupt Pending Flag for T1B capture
edge
Bit 7
Reserved
Bit 7
T0EN
Timer T0 Interrupt Enable (Bit 12 toggle)
µWPND MICROWIRE/PLUS interrupt pending
T1ENB
Timer T3 Interrupt Enable for T3B Input capture
edge
T3ENB
Bit 0
The T3CNTRL register contains the following bits:
T3C3
Timer T3 mode control bit
T3C2
Timer T3 mode control bit
T3C1
Timer T3 mode control bit
T3C0
Timer T3 Start/Stop control in timer
modes 1 and 2, Timer T3 Underflow Interrupt
Pending Flag in timer mode 3
T3PNDA Timer T3 Interrupt Pending Flag (Autoreload
23
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COP8AME9
10.0 Functional Description
COP8AME9
11.3 REGISTERS
11.0 In-System Programming
There are six registers required to support ISP: Address
Register Hi byte (ISPADHI), Address Register Low byte
(ISPADLO), Read Data Register (ISPRD), Write Data Register (ISPWR), Write Timing Register (PGMTIM), and the
Control Register (ISPCNTRL). The ISPCNTRL Register is
not available to the user.
11.1 INTRODUCTION
This device provides the capability to program the program
memory while installed in an application board. This feature
is called In System Programming (ISP). It provides a means
of ISP by using the MICROWIRE/PLUS, or the user can
provide his own, customized ISP routine. The factory installed ISP uses the MICROWIRE/PLUS port. The user can
provide his own ISP routine that uses any of the capabilities
of the device, such as USART, parallel port, etc.
11.3.1 ISP Address Registers
The address registers (ISPADHI & ISPADLO) are used to
specify the address of the byte of data being written or read.
For page erase operations, the address of the beginning of
the page should be loaded. For mass erase operations,
0000 must be placed into the address registers. When reading the Option register, FFFF (hex) should be placed into the
address registers. Registers ISPADHI and ISPADLO are
cleared to 00 on Reset. These registers can be loaded from
either flash program memory or Boot ROM and must be
maintained for the entire duration of the operation.
11.2 FUNCTIONAL DESCRIPTION
The organization of the ISP feature consists of the user flash
program memory, the factory boot ROM, and some registers
dedicated to performing the ISP function. See Figure 12 for
a simplified block diagram. The factory installed ISP that
uses MICROWIRE/PLUS is located in the Boot ROM. The
size of the Boot ROM is 1K bytes and also contains code to
facilitate in system emulation capability. If a user chooses to
write his own ISP routine, it must be located in the flash
program memory.
Note: The actual memory address of the Option Register is
1FFF (hex), however the MICROWIRE/PLUS ISP routines
require the address FFFF (hex) to be used to read the
Option Register when the Flash Memory is secured.
TABLE 4. High Byte of ISP Address
ISPADHi
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Addr 15
Addr 14
Addr 13
Addr 12
Addr 11
Addr 10
Addr 9
Addr 8
TABLE 5. Low Byte of ISP Address
ISPADLO
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Addr 7
Addr 6
Addr 5
Addr 4
Addr 3
Addr 2
Addr 1
Addr 0
11.3.2 ISP Read Data Register
The Read Data Register (ISPRD) contains the value read
back from a read operation. This register can be accessed
from either flash program memory or Boot ROM. This register is undefined on Reset.
20006317
FIGURE 12. Block Diagram of ISP
As described in Section 10.5 OPTION REGISTER, there is a
bit, FLEX, that controls whether the device exits RESET
executing from the flash memory or the Boot ROM. The user
must program the FLEX bit as appropriate for the application. In the erased state, the FLEX bit = 0 and the device will
power-up executing from Boot ROM. When FLEX = 0, this
assumes that either the MICROWIRE/PLUS ISP routine or
external programming is being used to program the device. If
using the MICROWIRE/PLUS ISP routine, the software in
the boot ROM will monitor the MICROWIRE/PLUS for commands to program the flash memory. When programming
the flash program memory is complete, the FLEX bit will
have to be programmed to a 1 and the device will have to be
reset, either by pulling external Reset to ground or by a
MICROWIRE/PLUS ISP EXIT command, before execution
from flash program memory will occur.
If FLEX = 1, upon exiting Reset, the device will begin executing from location 0000 in the flash program memory. The
assumption, here, is that either the application is not using
ISP, is using MICROWIRE/PLUS ISP by jumping to it within
the application code, or is using a customized ISP routine. If
a customized ISP routine is being used, then it must be
programmed into the flash memory by means of the
MICROWIRE/PLUS ISP or external programming as described in the preceding paragraph.
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Bit 7
TABLE 6. ISP Read Data Register
ISPRD
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
11.3.3 ISP Write Data Register
The Write Data Register (ISPWR) contains the data to be
written into the specified address. This register is undetermined on Reset. This register can be accessed from either
flash program memory or Boot ROM. The Write Data register
must be maintained for the entire duration of the operation.
TABLE 7. ISP Write Data Register
ISPWR
24
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
Bit1
Bit0
frequency. This register can be loaded from either flash
program memory or Boot ROM and must be maintained for
the entire duration of the operation. The MICROWIRE/PLUS
ISP routine that is resident in the boot ROM requires that this
Register be defined prior to any access to the Flash memory.
Refer to section Section 11.7 MICROWIRE/PLUS ISP for
more information on available ISP commands. On Reset, the
PGMTIM register is loaded with the value that corresponds
to 10 MHz frequency for CKI.
(Continued)
11.3.4 ISP Write Timing Register
The Write Timing Register (PGMTIM) is used to control the
width of the timing pulses for write and erase operations. The
value to be written into this register is dependent on the
frequency of CKI and is shown in Table 8. This register must
be written before any write or erase operation can take
place. It only needs to be loaded once, for each value of CKI
TABLE 8. PGMTIM Register Format
PGMTIM
Register Bit
CKI Frequency Range
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
1
0
37.5 kHz–50 kHz
0
0
0
0
0
0
1
1
50 kHz–66.67 kHz
0
0
0
0
0
1
0
0
62.5 kHz–83.3 kHz
0
0
0
0
0
1
0
1
75 kHz–100 kHz
0
0
0
0
0
1
1
1
100 kHz–133 kHz
0
0
0
0
1
0
0
0
112.5 kHz–150 kHz
0
0
0
0
1
0
1
1
150 kHz–200 kHz
0
0
0
0
1
1
1
1
200 kHz–266.67 kHz
0
0
0
1
0
0
0
1
225 kHz–300 kHz
0
0
0
1
0
1
1
1
300 kHz–400 kHz
0
0
0
1
1
1
0
1
375 kHz–500 kHz
0
0
1
0
0
1
1
1
500 kHz–666.67 kHz
0
0
1
0
1
1
1
1
600 kHz–800 kHz
0
0
1
1
1
1
1
1
800 kHz–1.067 MHz
0
1
0
0
0
1
1
1
1 MHz–1.33 MHz
0
1
0
0
1
0
0
0
1.125 MHz–1.5 MHz
0
1
0
0
1
0
1
1
1.5 MHz–2 MHz
0
1
0
0
1
1
1
1
2 MHz–2.67 MHz
0
1
0
1
0
1
0
0
2.625 MHz–3.5 MHz
0
1
0
1
1
0
1
1
3.5 MHz–4.67 MHz
0
1
1
0
0
0
1
1
4.5 MHz–6 MHz
0
1
1
0
1
1
1
1
6 MHz–8 MHz
0
1
1
1
1
0
1
1
7.5 MHz–10 MHz
R
R/W
R/W
R/W
R/W
R/W
R/W
R/W
11.4 MANEUVERING BACK AND FORTH BETWEEN
FLASH MEMORY AND BOOT ROM
When using ISP, at some point, it will be necessary to
maneuver between the flash program memory and the Boot
ROM, even when using customized ISP routines. This is
because it’s not possible to execute from the flash program
memory while it’s being programmed.
Two instructions are available to perform the jumping back
and forth: Jump to Boot (JSRB) and Return to Flash (RETF).
The JSRB instruction is used to jump from flash memory to
Boot ROM, and the RETF is used to return from the Boot
ROM back to the flash program memory. See Section 22.0
Instruction Set for specific details on the operation of these
instructions.
The JSRB instruction must be used in conjunction with the
Key register. This is to prevent jumping to the Boot ROM in
the event of run-away software. For the JSRB instruction to
25 kHz–33.3 kHz
actually jump to the Boot ROM, the Key bit must be set. This
is done by writing the value shown in Table 9 to the Key
register. The Key is a 6 bit key and, if the key matches, the
KEY bit will be set for 8 instruction cycles. The JSRB instruction must be executed while the KEY bit is set. If the KEY
does not match, then the KEY bit will not be set and the
JSRB will jump to the specified location in the flash memory.
In emulation mode, if a breakpoint is encountered while the
KEY is set, the counter that counts the instruction cycles will
be frozen until the breakpoint condition is cleared. If an
interrupt occurs while the key is set, the Key will expire
before interrupt service is complete. It is recommended
that the software globally disable interrupts before setting the key and re-enable interrupts on completion of
Boot ROM execution. The Key register is a memory
mapped register. Its format when writing is shown in Table 9.
25
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COP8AME9
11.0 In-System Programming
COP8AME9
11.0 In-System Programming
4.
After VCC is valid and stable, connect a voltage between
2 x VCC and VCC+7V to the G6 pin. Ensure that the rise
time of the high voltage on G6 is slower than the minimum in the Electrical Specifications.Figure 13 shows a
possible circuit dliagram for implementing the 2 x VCC.
Be aware of the typical input current on the G6 pin when
the high voltage is applied. The resistor used in the RC
network, and the high voltage used, should be chosen to
keep the high voltage at the G6 pin between 2 x VCC and
VCC+7V.
5.
6.
Pull RESET High.
After a delay of at least three instruction cycles, remove
the high voltage from G6.
(Continued)
TABLE 9. KEY Register Write Format
KEY When Writing
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
1
0
0
1
1
0
X
X
Bits 7–2: Key value that must be written to set the KEY bit.
Bits 1–0: Don’t care.
11.5 FORCED EXECUTION FROM BOOT ROM
When the user is developing a customized ISP routine, code
lockups due to software errors may be encountered. The
normal, and preferred, method to recover from these conditions is to reprogram the device with the corrected code by
either an external parallel programmer or the emulation
tools. As a last resort, when this equipment is not available,
there is a hardware method to get out of these lockups and
force execution from the Boot ROM MICROWIRE/PLUS
routine. The customer will then be able to erase the Flash
Memory code and start over.
The method to force this condition is to drive the G6 pin to
high voltage (2 x VCC) and activate Reset. The high voltage
condition on G6 must not be applied before VCC is valid and
stable, and must be held for at least 3 instruction cycles
longer than Reset is active. This special condition will bypass checking the state of the Flex bit in the Option Register
and will start execution from location 0000 in the Boot ROM.
In this state, the user can input the appropriate commands,
using MICROWIRE/PLUS, to erase the flash program
memory and reprogram it. If the device is subsequently reset
before the Flex bit has been erased by specific Page Erase
or Mass Erase ISP commands, execution will start from
location 0000 in the Flash program memory. The high voltage (2 x VCC) on G6 will not erase either the Flex or the
Security bit in the Option Register. The Security bit, if set,
can only be erased by a Mass Erase of the entire contents of
the Flash Memory unless under the control of User ISP
routines in the Application Program.
While the G6 pin is at high voltage, the Load Clock will be
output onto G5, which will look like an SK clock to the
MICROWIRE/PLUS routine executing in slave mode. However, when G6 is at high voltage, the G6 input will also look
like a logic 1. The MICROWIRE/PLUS routine in Boot ROM
monitors the G6 input, waits for it to go low, debounces it,
and then enables the ISP routine. CAUTION: The Load clock
on G5 could be in conflict with the user’s external SK. It is up
to the user to resolve this conflict, as this condition is considered a minor issue that’s only encountered during software development. The user should also be cautious of
the high voltage applied to the G6 pin. This high voltage
could damage other circuitry connected to the G6 pin
(e.g. the parallel port of a PC). The user may wish to
disconnect other circuitry while G6 is connected to the high
voltage.
VCC must be valid and stable before high voltage is applied
to G6.
The correct sequence to be used to force execution from
Boot ROM is :
1. Disconnect G6 from the source of data for MICROWIRE/
PLUS ISP.
2. Apply VCC to the device.
3. Pull RESET Low.
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20006366
FIGURE 13. Circuit Diagram for Implementing the 2 x
VCC
11.6 RETURN TO FLASH MEMORY WITHOUT
HARDWARE RESET
After programming the entire program memory, including
options, it is necessary to exit the Boot ROM and return to
the flash program memory for program execution. Upon
receipt and completion of the EXIT command through the
MICROWIRE/PLUS ISP, the ISP code will reset the part and
begin execution from the flash program memory as described in the Reset section. This assumes that the FLEX bit
in the Option register was programmed to 1.
11.7 MICROWIRE/PLUS ISP
National Semiconductor provides a program, which is available from our web site at www.national.com/cop8, that is
capable of programming a device from the parallel port of a
PC. The software accepts manually input commands and is
capable of downloading standard Intel HEX Format files.
Users who wish to write their own MICROWIRE/PLUS ISP
host software should refer to the COP8 FLASH ISP User
Manual, available from the same web site. This document
includes details of command format and delays necessary
between command bytes.
The MICROWIRE/PLUS ISP supports the following features
and commands:
• Write a value to the ISP Write Timing Register. NOTE:
This must be the first command after entering
MICROWIRE/PLUS ISP mode.
• Erase the entire flash program memory (mass erase).
• Erase a page at a specified address.
• Read Option register.
• Read a byte from a specified address.
•
•
•
•
26
Write a byte to a specified address.
Read multiple bytes starting at a specified address.
Write multiple bytes starting at a specified address.
Exit ISP and return execution to flash program memory.
COP8AME9
11.0 In-System Programming
(Continued)
The following table lists the MICROWIRE/PLUS ISP commands and provides information on required parameters and
return values.
TABLE 10. MICROWIRE/PLUS ISP Commands
Command
Function
Command
Value (Hex)
Parameters
Return Data
PGMTIM_SET
Write Pulse Timing
Register
0x3B
Value
N/A
PAGE_ERASE
Page Erase
0xB3
Starting Address of
Page
N/A
MASS_ERASE
Mass Erase
0xBF
Confirmation Code
N/A (The entire Flash
Memory will be erased)
READ_BYTE
Read Byte
0x1D
Address High, Address
Low
Data Byte if Security not
set. 0xFF if Security set.
Option Register if address
= 0xFFFF, regardless of
Security
BLOCKR
Block Read
0xA3
Address High, Address
Low, Byte Count (n)
High, Byte Count (n)
Low
0 ≤ n ≤ 32767
n Data Bytes if Security
not set.
n Bytes of 0xFF if
Security set.
WRITE_BYTE
Write Byte
0x71
Address High, Address
Low, Data Byte
N/A
BLOCKW
Block Write
0x8F
Address High, Address
Low, Byte Count (0 ≤ n
≤ 16), n Data Bytes
N/A
EXIT
EXIT
0xD3
N/A
N/A (Device will Reset)
INVALID
N/A
Any other invalid
command will be
ignored
N/A
Note: The user must ensure that Block Writes do not cross a 64 byte boundary within one operation.
11.8 USER ISP AND VIRTUAL E2
• Copy a block of data from RAM into flash program
memory.
• Copy a block of data from program flash memory to RAM.
The following table lists the User ISP/Virtual E2 commands,
required parameters and return data, if applicable. The command entry point is used as an argument to the JSRB
instruction. Table 12 lists the Ram locations and Peripheral
Registers, used for User ISP and Virtual E2, and their expected contents. Please refer to the COP8 FLASH ISP User
Manual for additional information and programming examples on the use of User ISP and Virtual E2.
The following commands will support transferring blocks of
data from RAM to flash program memory, and vice-versa.
The user is expected to enforce application security in this
case.
• Erase the entire flash program memory (mass erase).
NOTE: Execution of this command will force the device
into the MICROWIRE/PLUS ISP mode.
• Erase a page of flash memory at a specified address.
• Read a byte from a specified address.
• Write a byte to a specified address.
27
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COP8AME9
11.0 In-System Programming
(Continued)
TABLE 11. User ISP/Virtual E2 Entry Points
Command/
Label
Function
Command
Entry Point
Parameters
Return Data
cpgerase
Page Erase
0x17
Register ISPADHI is loaded by the user
with the high byte of the address.
Register ISPADLO is loaded by the
user with the low byte of the address.
N/A (A page of memory beginning at
ISPADHI, ISPADLO will be erased)
cmserase
Mass Erase
0x1A
Accumulator A contains the
confirmation key 0x55.
N/A (The entire Flash Memory will be
erased)
creadbf
Read Byte
0x11
Register ISPADHI is loaded by the user
with the high byte of the address.
Register ISPADLO is loaded by the
user with the low byte of the address.
Data Byte in Register ISPRD.
cblockr
Block Read
0x26
Register ISPADHI is loaded by the user
with the high byte of the address.
Register ISPADLO is loaded by the
user with the low byte of the address.
X pointer contains the beginning RAM
address where the result(s) will be
returned.
Register BYTECOUNTLO contains the
number of n bytes to read
(0 ≤ n ≤ 255). It is up to the user to
setup the segment register.
n Data Bytes, Data will be returned
beginning at a location pointed to by
the RAM address in X.
cwritebf
Write Byte
0x14
Register ISPADHI is loaded by the user
with the high byte of the address.
Register ISPADLO is loaded by the
user with the low byte of the address.
Register ISPWR contains the Data
Byte to be written.
N/A
cblockw
Block Write
0x23
Register ISPADHI is loaded by the user
with the high byte of the address.
Register ISPADLO is loaded by the
user with the low byte of the address.
Register BYTECOUNTLO contains the
number of n bytes to write (0 ≤ n ≤ 16).
The combination of the
BYTECOUNTLO and the ISPADLO
registers must be set such that the
operation will not cross a 64 byte
boundary.
X pointer contains the beginning RAM
address of the data to be written.
It is up to the user to setup the
segment register.
N/A
exit
EXIT
0x62
N/A
N/A (Device will Reset)
uwisp
MICROWIRE/
PLUS
ISP Start
0x00
N/A
N/A (Divice will be in
MICROWIRE/PLUS ISP Mode. Must
be terminated by MICROWIRE/PLUS
ISP EXIT command which will Reset
the device)
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28
(Continued)
TABLE 12. Register and Bit Name Definitions
Register
Name
RAM
Location
Purpose
ISPADHI
High byte of Flash Memory Address
0xA9
ISPADLO
Low byte of Flash Memory Address
0xA8
ISPWR
The user must store the byte to be written into this register before jumping into the
write byte routine.
0xAB
ISPRD
Data will be returned to this register after the read byte routine execution.
0xAA
ISPKEY
The ISPKEY Register is required to validate the JSRB instruction and must be loaded
within 6 instruction cycles before the JSRB.
0xE2
BYTECOUNTLO
Holds the count of the number of bytes to be read or written in block operations.
0xF1
PGMTIM
Write Timing Register. This register must be loaded, by the user, with the proper value
before execution of any USER ISP Write or Erase operation. Refer to Table 8 for the
correct value.
0xE1
Confirmation Code
The user must place this code in the accumulator before execution of a Flash Memory
Mass Erase command.
A
KEY
Must be transferred to the ISPKEY register before execution of a JSRB instruction.
11.9 RESTRICTIONS ON SOFTWARE WHEN CALLING
ISP ROUTINES IN BOOT ROM
1. The hardware will disable interrupts from occurring. The
hardware will leave the GIE bit in its current state, and if
set, the hardware interrupts will occur when execution is
returned to Flash Memory. Subsequent interrupts, during ISP operation, from the same interrupt source will be
lost. Interrupt may occur between setting the KEY
and executing the JSRB instruction. In this case, the
KEY will expire before the JSRB is executed. It is,
therefore, recommended that the software globally
disable interrupts before setting the Key.
2. The security feature in the MICROWIRE/PLUS ISP is
guaranteed by software and not hardware. When executing the MICROWIRE/PLUS ISP routine, the security
bit is checked prior to performing all instructions. Only
the mass erase command, write PGMTIM register, and
reading the Option register is permitted within the
MICROWIRE/PLUS ISP routine. When the user is performing his own ISP, all commands are permitted. The
entry points from the user’s ISP code do not check for
security. It is the burden of the user to guarantee his own
security. See the Security bit description in Section 10.5
OPTION REGISTER for more details on security.
3. When using any of the ISP functions in Boot ROM, the
ISP routines will service the WATCHDOG within the
selected upper window. Upon return to flash memory,
the WATCHDOG is serviced, the lower window is enabled, and the user can service the WATCHDOG anytime following exit from Boot ROM, but must service it
within the selected upper window to avoid a WATCHDOG error.
4. Block Writes can start anywhere in the page of Flash
memory, but cannot cross half page or full page boundaries.
5. The user must ensure that a page erase or a mass
erase is executed between two consecutive writes to
0x98
the same location in Flash memory. Two writes to
the same location without an intervening erase will
produce unpredicatable results including possible
disturbance of unassociated locations.
11.10 FLASH MEMORY DURABILITY CONSIDERATIONS
The endurance of the Flash Memory (number of possible
Erase/Write cycles) is a function of the erase time and the
lowest temperature at which the erasure occurs. If the device
is to be used at low temperature, additional erase operations
can be used to extend the erase time. The user can determine how many times to erase a page based on what
endurance is desired for the application (e.g. four page
erase cycles, each time a page erase is done, may be
required to achieve the typical 100k Erase/Write cycles in an
application which may be operating down to 0˚C). Also, the
customer can verify that the entire page is erased, with
software, and request additional erase operations if desired.
TABLE 13. Typical Flash Memory Endurance
Low End of Operating Temp Range
29
Erase
Time
−40˚C
−20˚C
0˚C
25˚C
> 25˚C
1 ms
60k
60k
60k
100k
100k
2 ms
60k
60k
60k
100k
100k
3 ms
60k
60k
60k
100k
100k
4 ms
60k
60k
100k
100k
100k
5 ms
70k
70k
100k
100k
100k
6 ms
80k
80k
100k
100k
100k
7 ms
90k
90k
100k
100k
100k
8 ms
100k
100k
100k
100k
100k
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COP8AME9
11.0 In-System Programming
COP8AME9
• WATCHDOG logic (See WATCHDOG description)
• Start up delay out of the HALT mode
• Start up delay from BOR
Figure 14 is a functional block diagram showing the structure
of the IDLE Timer and its associated interrupt logic.
Bits 11 through 15 of the ITMR register can be selected for
triggering the IDLE Timer interrupt. Each time the selected
bit underflows (every 4k, 8k, 16k, 32k or 64k selected
clocks), the IDLE Timer interrupt pending bit T0PND is set,
thus generating an interrupt (if enabled), and bit 6 of the Port
G data register is reset, thus causing an exit from the IDLE
mode if the device is in that mode.
In order for an interrupt to be generated, the IDLE Timer
interrupt enable bit T0EN must be set, and the GIE (Global
Interrupt Enable) bit must also be set. The T0PND flag and
T0EN bit are bits 5 and 4 of the ICNTRL register, respectively. The interrupt can be used for any purpose. Typically, it
is used to perform a task upon exit from the IDLE mode. For
more information on the IDLE mode, refer to section Section
13.0 Power Saving Features.
The Idle Timer period is selected by bits 0–2 of the ITMR
register Bit 3 of the ITMR Register is reserved and should
not be used as a software flag. Bits 4 through 7 of the ITMR
Register are used by the dual clock and are described in
Section 13.0 Power Saving Features.
12.0 Timers
The device contains a very versatile set of timers (T0, T1, T2
and T3). Timers T1, T2 and T3 and associated autoreload/
capture registers power up containing random data.
12.1 TIMER T0 (IDLE TIMER)
The device supports applications that require maintaining
real time and low power with the IDLE mode. This IDLE
mode support is furnished by the IDLE Timer T0, which is a
16-bit timer. The user cannot read or write to the IDLE Timer
T0, which is a count down timer.
As described in Section 13.0 Power Saving Features, the
clock to the IDLE Timer depends on which mode the device
is in. If the device is in High Speed mode, the clock to the
IDLE Timer is the instruction cycle clock (one-fifth of the CKI
frequency). If the device is in Dual Clock mode or Low Speed
mode, the clock to the IDLE Timer is the 32 kHz clock. For
the remainder of this section, the term “selected clock” will
refer to the clock selected by the Power Save mode of the
device. During Dual Clock and Low Speed modes, the divide
by 10 that creates the instruction cycle clock is disabled, to
minimize power consumption.
In addition to its time base function, the Timer T0 supports
the following functions:
• Exit out of the Idle Mode (See Idle Mode description)
20006318
FIGURE 14. Functional Block Diagram for Idle Timer T0
TABLE 14. Idle Timer Window Length
Idle Timer Period
Idle Timer Period
ITSEL2
ITSEL1
ITSEL0
High Speed
Mode
Dual Clock
or
Low Speed
Mode
65,536 inst.
cycles
2 seconds
ITSEL2
ITSEL1
ITSEL0
High Speed
Mode
Dual Clock
or
Low Speed
Mode
1
0
0
0
0
0
4,096 inst.
cycles
0.125
seconds
1
0
1
Reserved - Undefined
0
0
1
8,192 inst.
cycles
0.25 seconds
1
1
0
Reserved - Undefined
1
1
1
Reserved - Undefined
0
1
0
16,384 inst.
cycles
0.5 seconds
0
1
1
32,768 inst.
cycles
1 second
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The ITSEL bits of the ITMR register are cleared on Reset
and the Idle Timer period is reset to 4,096 instruction cycles.
30
(Continued)
HSTCR
12.1.1 ITMR Register
LSON HSON
Bit 7
Bit 6
DCEN
CCK
SEL
Bit 5
Bit 4
Bits 7–4: Described
Features.
in
RSVD ITSEL2 ITSEL1 ITSEL0
Bit 3
Section
Bit 2
13.0
Bit 1
Power
Bit 0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit
1
Bit
0
T2IDLE
0
0
0
0
0
T3HS
T2HS
12.2.2 Mode 1. Processor Independent PWM Mode
One of the timer’s operating modes is the Processor Independent PWM mode. In this mode, the timers generate a
“Processor Independent” PWM signal because once the
timer is set up, no more action is required from the CPU
which translates to lower software overhead and greater
throughput. The user software services the timer block only
when the PWM parameters require updating. This capability
is provided by the fact that the timer has two separate 16-bit
reload registers. One of the reload registers contains the
“ON” time while the other holds the “OFF” time. By contrast,
a microcontroller that has only a single reload register requires an additional software to update the reload value
(alternate between the on-time/off-time).
Saving
Note: Documentation for previous COP8 devices, which included the Programmable Idle Timer, recommended the user
write zero to the high order bits of the ITMR Register. If
existing programs are updated to use this device, writing
zero to these bits will cause the device to reset (see Section
13.0 Power Saving Features).
RSVD: This bit is reserved and must be set to 0.
ITSEL2:0: Selects the Idle Timer period as described in
Table 14, Idle Timer Window Length.
Any time the IDLE Timer period is changed there is the
possibility of generating a spurious IDLE Timer interrupt by
setting the T0PND bit. The user is advised to disable IDLE
Timer interrupts prior to changing the value of the ITSEL bits
of the ITMR Register and then clear the T0PND bit before
attempting to synchronize operation to the IDLE Timer.
The timer can generate the PWM output with the width and
duty cycle controlled by the values stored in the reload
registers. The reload registers control the countdown values
and the reload values are automatically written into the timer
when it counts down through 0, generating interrupt on each
reload. Under software control and with minimal overhead,
the PWM outputs are useful in controlling motors, triacs, the
intensity of displays, and in providing inputs for data acquisition and sine wave generators.
12.2 TIMER T1, TIMER T2, AND TIMER T3
The device has a set of three powerful timer/counter blocks,
T1, T2, and T3. Since T1, T2 and T3 are identical, except for
the high speed operation of T2 and T3, all comments are
equally applicable to any of the three timer blocks which will
be referred to as Tx. Differences between the timers will be
specifically noted.
The core 16-bit timer is designated T1, this section uses Tx
to refer to timer T1 and all additional timers that operate in
exactly the same manner as timer T1, with the exception of
the high speed capability described later.
Each timer block consists of a 16-bit timer, Tx, and two
supporting 16-bit autoreload/capture registers, RxA and
RxB. Each timer block has two pins associated with it, TxA
and TxB. The pin TxA supports I/O required by the timer
block, while the pin TxB is an input to the timer block. The
timer block has three operating modes: Processor Independent PWM mode, External Event Counter mode, and Input
Capture mode.
The control bits TxC3, TxC2, and TxC1 allow selection of the
different modes of operation.
In this mode, the timer Tx counts down at a fixed rate of tC
(T2 and T3 may be selected to operate from MCLK). Upon
every underflow the timer is alternately reloaded with the
contents of supporting registers, RxA and RxB. The very first
underflow of the timer causes the timer to reload from the
register RxA. Subsequent underflows cause the timer to be
reloaded from the registers alternately beginning with the
register RxB.
Figure 15 shows a block diagram of the timer in PWM mode.
The underflows can be programmed to toggle the TxA output
pin. The underflows can also be programmed to generate
interrupts.
Underflows from the timer are alternately latched into two
pending flags, TxPNDA and TxPNDB. The user must reset
these pending flags under software control. Two control
enable flags, TxENA and TxENB, allow the interrupts from
the timer underflow to be enabled or disabled. Setting the
timer enable flag TxENA will cause an interrupt when a timer
underflow causes the RxA register to be reloaded into the
timer. Setting the timer enable flag TxENB will cause an
interrupt when a timer underflow causes the RxB register to
be reloaded into the timer. Resetting the timer enable flags
will disable the associated interrupts.
Either or both of the timer underflow interrupts may be
enabled. This gives the user the flexibility of interrupting
once per PWM period on either the rising or falling edge of
the PWM output. Alternatively, the user may choose to interrupt on both edges of the PWM output.
12.2.1 Timer Operating Speeds
Each of the Tx timers, except T1, have the ability to operate
at either the instruction cycle frequency (low speed) or the
internal clock frequency (MCLK). For 10 MHz CKI, the instruction cycle frequency is 2 MHz and the internal clock
frequency is 20 MHz. This feature is controlled by the High
Speed Timer Control Register, HSTCR. Its format is shown
below. To place a timer, Tx, in high speed mode, set the
appropriate TxHS bit to 1. For low speed operation, clear the
appropriate TxHS bit to 0. This register is cleared to 00 on
Reset.
The T2IDLE bit is used to allow T2 operation while the
device is in Idle mode. See Section 12.4 TIMER T2 OPERATION IN IDLE MODE for further information.
31
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COP8AME9
12.0 Timers
COP8AME9
12.0 Timers
The choice of TMR2LO bit 6 works, but may introduce delay
at the wrong time in some applications, particularly if bit 7 is
a one. The above example shows the workaround if only one
timer (T2 or T3) is used in high speed PWM mode. If both
Timers T2 and T3 are used in high speed PWM mode, the
program becomes significantly more complicated, since the
execution of the SBIT or RBIT instruction must be delayed
until the PWM output of neither T2 nor T3 is likely to change
during the execution of the instruction.
(Continued)
12.2.3 Mode 2. External Event Counter Mode
This mode is quite similar to the processor independent
PWM mode described above. The main difference is that the
timer, Tx, is clocked by the input signal from the TxA pin after
synchronization to the appropriate internal clock (tC or
MCLK). The Tx timer control bits, TxC3, TxC2 and TxC1
allow the timer to be clocked either on a positive or negative
edge from the TxA pin. Underflows from the timer are latched
into the TxPNDA pending flag. Setting the TxENA control flag
will cause an interrupt when the timer underflows.
In this mode the input pin TxB can be used as an independent positive edge sensitive interrupt input if the TxENB
control flag is set. The occurrence of a positive edge on the
TxB input pin is latched into the TxPNDB flag.
Figure 16 shows a block diagram of the timer in External
Event Counter mode.
20006319
FIGURE 15. Timer in PWM Mode
If either T2 or T3 is used in High Speed PWM mode and an
SBIT or RBIT instruction operates on any other bit of the
PORT L Data Register, the PWM output may appear to miss
a toggle and thus be inverted. If the timer causes the PWM
output to toggle in the middle of an SBIT or RBIT operation
on the PORTLD Register, the PWM output may be set back
to its state before the output toggle by the operation of the
SBIT/RBIT. This can have the effect of generating a shortened pulse (less than one instruction cycle in width) on the
PWM output and inverting the PWM duty cycle.
If the PWM Timer is used in low speed mode or if the PWM
output toggle is synchronous with the end of the instruction
cycle, this problem is not seen. The following figure illustrates the PWM output when the failure is seen.
The user should be aware of the state of Timers T2 and T3
before any SBIT or RBIT instructions are executed which
operate on the PORTLD register. If the PWM output is close
to toggling, the user should delay the SBIT or RBIT instruction.
The following program sequence works to delay the operation. The user may wish to experiment with other sequences
to see which best fits the application and to make sure that
the time between the completion of the tests and the modification of PORTLD is not too long. The sequence can easily
be modified to work with Timer T3.
LD B,#TMR2HI ;POINT B TO THE TIMER
LD A,[B-] ;GET THE VALUE IN THE TIMER
IFGT A,#0 ;IF NON ZERO
JP GOOD ;WE HAVE TIME
WAIT: IFBIT 6,[B] ;TEST BIT 6 OF THE TIMER
JP GOOD ;TIME TO GET IT DONE SAFELY
JP WAIT ;WAIT A WHILE
GOOD: SBIT 2,PORTLD ;GO AHEAD AND SET THE
⇒ BIT
The above program uses specific bits of the port for explanation purposes only.
The above program uses the SBIT instruction by way of
example. The RBIT instruction will have the same effect.
The above sequence will not work properly for PWM times
shorter than 64 CPU Clock cycles.
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Note: The PWM output is not available in this mode since the
TxA pin is being used as the counter input clock.
20006320
FIGURE 16. Timer in External Event Counter Mode
12.2.4 Mode 3. Input Capture Mode
The device can precisely measure external frequencies or
time external events by placing the timer block, Tx, in the
input capture mode. In this mode, the reload registers serve
as independent capture registers, capturing the contents of
the timer when an external event occurs (transition on the
timer input pin). The capture registers can be read while
maintaining count, a feature that lets the user measure
elapsed time and time between events. By saving the timer
value when the external event occurs, the time of the external event is recorded. Most microcontrollers have a latency
time because they cannot determine the timer value when
32
(Continued)
12.3 TIMER CONTROL FLAGS
the external event occurs. The capture register eliminates
the latency time, thereby allowing the applications program
to retrieve the timer value stored in the capture register.
In this mode, the timer Tx is constantly running at the fixed tC
or MCLK rate. The two registers, RxA and RxB, act as
capture registers. Each register also acts in conjunction with
a pin. The register RxA acts in conjunction with the TxA pin
and the register RxB acts in conjunction with the TxB pin.
The timer value gets copied over into the register when a
trigger event occurs on its corresponding pin after synchronization to the appropriate internal clock (tC or MCLK). Control bits, TxC3, TxC2 and TxC1, allow the trigger events to be
specified either as a positive or a negative edge. The trigger
condition for each input pin can be specified independently.
The trigger conditions can also be programmed to generate
interrupts. The occurrence of the specified trigger condition
on the TxA and TxB pins will be respectively latched into the
pending flags, TxPNDA and TxPNDB. The control flag
TxENA allows the interrupt on TxA to be either enabled or
disabled. Setting the TxENA flag enables interrupts to be
generated when the selected trigger condition occurs on the
TxA pin. Similarly, the flag TxENB controls the interrupts
from the TxB pin.
Underflows from the timer can also be programmed to generate interrupts. Underflows are latched into the timer TxC0
pending flag (the TxC0 control bit serves as the timer underflow interrupt pending flag in the Input Capture mode). Consequently, the TxC0 control bit should be reset when entering the Input Capture mode. The timer underflow interrupt is
enabled with the TxENA control flag. When a TxA interrupt
occurs in the Input Capture mode, the user must check both
the TxPNDA and TxC0 pending flags in order to determine
whether a TxA input capture or a timer underflow (or both)
caused the interrupt.
Figure 17 shows a block diagram of the timer T1 in Input
Capture mode. T2 and T3 are identical to T1.
The control bits and their functions are summarized below.
TxC3
Timer mode control
TxC2
TxC1
Timer mode control
Timer mode control
TxC0
Timer Start/Stop control in Modes 1 and 2 (Processor Independent PWM and External Event
Counter), where 1 = Start, 0 = Stop
Timer Underflow Interrupt Pending Flag in Mode
3 (Input Capture)
TxPNDA Timer Interrupt Pending Flag
TxENA Timer Interrupt Enable Flag
1 = Timer Interrupt Enabled
0 = Timer Interrupt Disabled
TxPNDB Timer Interrupt Pending Flag
TxENB Timer Interrupt Enable Flag
1 = Timer Interrupt Enabled
0 = Timer Interrupt Disabled
The timer mode control bits (TxC3, TxC2 and TxC1) are
detailed in Table 15, Timer Operating Modes.
When the high speed timers are counting in high speed
mode, directly altering the contents of the timer upper or
lower registers, the PWM outputs or the reload registers is
not recommended. Bit operations can be particularly problematic. Since any of these six registers or the PWM outputs
can change as many as ten times in a single instruction
cycle, performing an SBIT or RBIT operation with the timer
running can produce unpredictable results. The recommended procedure is to stop the timer, perform any changes
to the timer, the PWM outputs or reload register values, and
then re-start the timer. This warning does not apply to the
timer control register. Any type of read/write operation, including SBIT and RBIT may be performed on this register in
any operating mode.
20006321
FIGURE 17. Timer in Input Capture Mode
33
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COP8AME9
12.0 Timers
COP8AME9
12.0 Timers
(Continued)
TABLE 15. Timer Operating Modes
1
0
1
PWM: TxA Toggle
Autoreload RA
Autoreload RB
tC or MCLK
1
0
0
PWM: No TxA
Toggle
Autoreload RA
Autoreload RB
tC or MCLK
0
0
0
External Event
Counter
Timer Underflow
Pos. TxB Edge
TxA Pos.
Edge
0
0
1
External Event
Counter
Timer Underflow
Pos. TxB Edge
TxA Neg.
Edge
0
1
0
Captures:
Pos. TxA Edge
Pos. TxB Edge
tC or MCLK
TxA Pos. Edge
or Timer
tC or MCLK
3
0
1
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1
1
1
0
1
1
Description
Timer
Counts On
1
1
TxC1
Interrupt B
Source
TxC3
2
TxC2
Interrupt A
Source
Mode
TxB Pos. Edge
Underflow
Captures:
Pos. TxA
Neg. TxB
TxA Pos. Edge
Edge or Timer
Edge
TxB Neg. Edge
Underflow
Captures:
Neg. TxA
Pos. TxB
TxA Neg. Edge
Edge or Timer
Edge
TxB Pos. Edge
Underflow
Captures:
Neg. TxA
Neg. TxB
TxA Neg. Edge
Edge or Timer
Edge
TxB Neg. Edge
Underflow
34
tC or MCLK
tC or MCLK
• Using the instruction cycle clock (tc)
• PWM: TxA Toggle
T2 should not be left in this special mode when entering
HALT. The T2IDLE bit must be reset to 0 before entering the
HALT mode to ensure that T2 remains in the same state
when exiting HALT as it was prior to entering HALT.
(Continued)
12.4 TIMER T2 OPERATION IN IDLE MODE
Timer T2 has a special mode that allows it to be operated in
IDLE mode. To use this mode, T2 must be configured as a
high speed timer, by setting T2HS = 1, and, also, configured
to run in the IDLE mode by setting the T2IDLE bit to 1 in the
HSTCR register. Table 16 shows the modes of operation
allowed for T2 during the IDLE mode. All the T2 modes are
allowed except the following:
TABLE 16. Timer T2 Mode Control Bits in IDLE Mode
Mode
1
2
3
Interrupt B
Source
Timer
Counts On
TxC2
TxC1
1
0
1
Not Allowed
1
0
0
PWM: No TxA
Toggle
Autoreload RA
Autoreload RB
MCLK
0
0
0
External Event
Counter
Timer Underflow
Pos. TxB Edge
TxA Pos.
Edge
0
0
1
External Event
Counter
Timer Underflow
Pos. TxB Edge
TxA Neg.
Edge
0
1
0
Captures:
Pos. TxA Edge
Pos. TxB Edge
MCLK
MCLK
1
0
1
1
0
1
1
1
1
Description
Interrupt A
Source
TxC3
TxA Pos. Edge
or Timer
TxB Pos. Edge
Underflow
Captures:
Pos. TxA
Pos.TxB
TxA Pos. Edge
Edge or Timer
Edge
TxB Neg. Edge
Underflow
Captures:
Neg. TxA
Pos. TxB
TxA Neg. Edge
Edge or Timer
Edge
TxB Pos. Edge
Underflow
Captures:
Neg. TxA
Neg. TxB
TxA Neg. Edge
Edge or Timer
Edge
TxB Neg. Edge
Underflow
MCLK
MCLK
12.4.1 Timer T2 Clocking Scheme
Table 17 shows the relationship between the T2 clock, the
Processor clock, and the T0 clock. Note that the T2 clock is
always equal to the processor clock frequency when enabled.
TABLE 17. Timer T2 Clocking Scheme
Device Clock Mode
High Speed
Dual Clock
Low Speed
Idle Mode
T0 Clock
Procesor
Clock
T2 Clock if
T2IDLE = 1
T2 Clock if
T2IDLE = 0
0
HS Clock
HS Clock
HS Clock
HS Clock
1
HS Clock
Off
HS Clock
Off
0
LS Clock
HS Clock
HS Clock
HS Clock
1
LS Clock
Off
HS Clock
Off
0
LS Clock
LS Clock
LS Clock
LS Clock
1
LS Clock
Off
LS Clock
Off
35
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COP8AME9
12.0 Timers
COP8AME9
ing modes are: High Speed, Dual Clock, and Low Speed.
Within each operating mode, the two power save modes are:
HALT and IDLE. In the HALT mode of operation, all microcontroller activities are stopped and power consumption is
reduced to a very low level. In this device, the HALT mode is
enabled and disabled by a bit in the Option register. The
IDLE mode is similar to the HALT mode, except that certain
sections of the device continue to operate, such as: the
on-board oscillator, the IDLE Timer (Timer T0), and the Clock
Monitor. This allows real time to be maintained. During
power save modes of operation, all on board RAM, registers,
I/O states and timers (with the exception of T0) are unaltered.
13.0 Power Saving Features
Today, the proliferation of battery-operated applications has
placed new demands on designers to drive power consumption down. Battery operated systems are not the only type of
applications demanding low power. The power budget constraints are also imposed on those consumer/industrial applications where well regulated and expensive power supply
costs cannot be tolerated. Such applications rely on low cost
and low power supply voltage derived directly from the
“mains” by using voltage rectifier and passive components.
Low power is demanded even in automotive applications,
due to increased vehicle electronics content. This is required
to ease the burden from the car battery. Low power 8-bit
microcontrollers supply the smarts to control batteryoperated, consumer/industrial, and automotive applications.
Two oscillators are used to support the three different operating modes. The high speed oscillator refers to the oscillator
connected to CKI and the low speed oscillator refers to the
32 kHz oscillator connected to pins L0 & L1. When using L0
and L1 for the low speed oscillator, the user must ensure that
the L0 and L1 pins are configured for hi-Z input, L1 is not
using CKX on the USART, and Multi-Input Wake-up for these
pins is disabled.
A diagram of the three modes is shown in Figure 18.
The device offers system designers a variety of low-power
consumption features that enable them to meet the demanding requirements of today’s increasing range of low-power
applications. These features include low voltage operation,
low current drain, and power saving features such as HALT,
IDLE, and Multi-Input Wake-Up (MIWU).
This device supports three operating modes, each of which
have two power save modes of operation. The three operat-
20006322
FIGURE 18. Diagram of Power Save Modes
lator. When HSON = 0, the high speed oscillator
is off. When HSON = 1, the high speed oscillator
is on. There is a startup time associated with this
oscillator. See the startup time table in the Oscillator Circuits section.
DCEN:
This bit selects the clock source for the Idle
Timer. If this bit = 0, then the high speed clock is
the clock source for the Idle Timer. If this bit = 1,
then the low speed clock is the clock source for
the Idle Timer. The low speed oscillator must be
started and stabilized before setting this bit to a
1.
CCKSEL: This bit selects whether the high speed clock or
low speed clock is gated to the microcontroller
core. When this bit = 0, the Core clock will be the
13.1 POWER SAVE MODE CONTROL REGISTER
The ITMR control register allows for navigation between the
three different modes of operation. It is also used for the Idle
Timer. The register bit assignments are shown below. This
register is cleared to 40 (hex) by Reset as shown below.
LSON
HSON
DCEN
CCK
SEL
RSVD
ITSEL2
ITSEL1
ITSEL0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
LSON:
HSON:
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This bit is used to turn-on the low-speed oscillator. When LSON = 0, the low speed oscillator is
off. When LSON = 1, the low speed oscillator is
on. There is a startup time associated with this
oscillator. See the Oscillator Circuits section.
This bit is used to turn-on the high speed oscil36
2.
(Continued)
Software clears LSON to 0.
13.3.1 High Speed Halt Mode
high speed clock. When this bit = 1, then the
Core clock will be the low speed clock. Before
switching this bit to either state, the appropriate
clock should be turned on and stabilized.
RSVD:
This bit is reserved and must be 0.
ITSEL2–0: These are bits used to control the Idle Timer.
See Section 12.1 TIMER T0 (IDLE TIMER) for
the description of these bits.
The fully static architecture of this device allows the state of
the microcontroller to be frozen. This is accomplished by
stopping the internal clock of the device during the HALT
mode. The controller also stops the CKI pin from oscillating
during the HALT mode. The processor can be forced to exit
the HALT mode and resume normal operation at any time.
During normal operation, the actual power consumption depends heavily on the clock speed and operating voltage
used in an application and is shown in the Electrical Specifications. In the HALT mode, the device only draws a small
leakage current, plus current for the BOR feature, plus any
current necessary for driving the outputs. Since total power
consumption is affected by the amount of current required to
drive the outputs, all I/Os should be configured to draw
minimal current prior to entering the HALT mode, if possible.
In order to reduce power consumption even further, the
power supply (VCC) can be reduced to a very low level
during the HALT mode, just high enough to guarantee retention of data stored in RAM. The allowed lower voltage level
(VR) is specified in the Electrical Specs section.
Table 18 lists the valid contents of the four most significant
bits of the ITMR Register. States are presented in the only
valid sequence. Any other value is illegal and will result in an
unrecoverable loss of a clock to the CPU core. To prevent
this condition, the device will automatically reset if any illegal
value is detected.
13.3.1.1 Entering The High Speed Halt Mode
The device enters the HALT mode under software control
when the Port G data register bit 7 is set to 1. All processor
action stops in the middle of the next instruction cycle, and
power consumption is reduced to a very low level.
TABLE 18. Valid Contents of Dual Clock Control Bits
13.3.1.2 Exiting The High Speed Halt Mode
There is a choice of methods for exiting the HALT mode: a
chip Reset using the RESET pin or a Multi-Input Wake-up.
DCEN CCKSEL
0
0
High Speed Mode. Core and Idle Timer
Clock = High Speed
1
0
Dual Clock Mode. Core clock = High
Speed; Idle Timer = Low Speed
1
1
Low Speed Mode. Core and Idle Timer
Clock = Low Speed
0
1
Invalid. If this is detected, the Low
Speed Mode will be forced.
LSON
HSON
DCEN
CCKSEL
0
1
0
0
High Speed
Mode
1
1
0
0
High
Speed/Dual
Clock Transition
1
1
1
0
Dual Clock
1
1
1
1
Dual Clock/Low
Speed
Transition
1
0
1
1
Low Speed
13.3.1.3 HALT Exit Using Reset
A device Reset, which is invoked by a low-level signal on the
RESET input pin, takes the device out of the HALT mode
and starts execution from address 0000H. The initialization
software should determine what special action is needed, if
any, upon start-up of the device from HALT. The initialization
of all registers following a RESET exit from HALT is described in the Reset section of this manual.
13.3.1.4 HALT Exit Using Multi-Input Wake-up
The device can be brought out of the HALT mode by a
transition received on one of the available Wake-up pins.
The pins used and the types of transitions sensed on the
Multi-input pins are software programmable. For information
on programming and using the Multi-Input Wake-up feature,
refer to the Multi-Input Wake-up section.
A start-up delay is required between the device wake-up and
the execution of program instructions, depending on the type
of chip clock. The start-up delay is mandatory, and is implemented whether or not the CLKDLY bit is set. This is because all crystal oscillators and resonators require some
time to reach a stable frequency and full operating amplitude.
The IDLE Timer (Timer T0) provides a fixed delay from the
time the clock is enabled to the time the program execution
begins. Upon exit from the HALT mode, the IDLE Timer is
enabled with a starting value of 256 and is decremented with
each instruction cycle. (The instruction clock runs at one-fifth
the frequency of the high speed oscillator.) An internal
Schmitt trigger connected to the on-chip CKI inverter ensures that the IDLE Timer is clocked only when the oscillator
has a large enough amplitude. (The Schmitt trigger is not
13.2 OSCILLATOR STABILIZATION
Both the high speed oscillator and low speed oscillator have
a startup delay associated with them. When switching between the modes, the software must ensure that the appropriate oscillator is started up and stabilized before switching
to the new mode. See Table 3, Startup Times for startup
times for both oscillators.
13.3 HIGH SPEED MODE OPERATION
This mode of operation allows high speed operation for both
the main Core clock and also for the IDLE Timer. This is the
default mode of the device and will always be entered upon
any of the Reset conditions described in the Reset section. It
can also be entered from Dual Clock mode. It cannot be
directly entered from the Low Speed mode without passing
through the Dual Clock mode first.
To enter from the Dual Clock mode, the following sequence
must be followed using two separate instructions:
1. Software clears DCEN to 0.
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COP8AME9
13.0 Power Saving Features
COP8AME9
13.0 Power Saving Features
13.3.1.5 Options
This device has two options associated with the HALT mode.
The first option enables the HALT mode feature, while the
second option disables HALT mode operation. Selecting the
disable HALT mode option will cause the microcontroller to
ignore any attempts to HALT the device under software
control. Note that this device can still be placed in the HALT
mode by stopping the clock input to the microcontroller, if the
program memory is masked ROM. See the Option section
for more details on this option bit.
(Continued)
part of the oscillator closed loop.) When the IDLE Timer
underflows, the clock signals are enabled on the chip, allowing program execution to proceed. Thus, the delay is equal
to 256 instruction cycles.
Note: To ensure accurate operation upon start-up of the
device using Multi-Input Wake-up, the instruction in the application program used for entering the HALT mode should
be followed by two consecutive NOP (no-operation) instructions.
20006323
FIGURE 19. Wake-up from HALT
13.3.2 High Speed Idle Mode
In the IDLE mode, program execution stops and power
consumption is reduced to a very low level as with the HALT
mode. However, the high speed oscillator, IDLE Timer (Timer
T0), T2 timer (T2HS = 1, T2IDLE = 1), and Clock Monitor
continue to operate, allowing real time to be maintained. The
device remains idle for a selected amount of time up to
65,536 instruction cycles, or 32.768 milliseconds with a 2
MHz instruction clock frequency, and then automatically exits the IDLE mode and returns to normal program execution.
The device is placed in the IDLE mode under software
control by setting the IDLE bit (bit 6 of the Port G data
register).
The IDLE Timer window is selectable from one of five values,
4k, 8k, 16k, 32k or 64k instruction cycles. Selection of this
value is made through the ITMR register.
The IDLE mode uses the on-chip IDLE Timer (Timer T0) to
keep track of elapsed time in the IDLE state. The IDLE Timer
runs continuously at the instruction clock rate, whether or not
the device is in the IDLE mode. Each time the bit of the timer
associated with the selected window toggles, the T0PND bit
is set, an interrupt is generated (if enabled), and the device
exits the IDLE mode if in that mode. If the IDLE Timer
interrupt is enabled, the interrupt is serviced before execution of the main program resumes. (However, the instruction
which was started as the part entered the IDLE mode is
completed before the interrupt is serviced. This instruction
should be a NOP which should follow the enter IDLE instruction.) The user must reset the IDLE Timer pending flag
(T0PND) before entering the IDLE mode.
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As with the HALT mode, this device can also be returned to
normal operation with a RESET, or with a Multi-Input
Wake-up input. Upon reset the ITMR register is cleared and
the ITMR register selects the 4,096 instruction cycle tap of
the IDLE Timer.
The IDLE Timer cannot be started or stopped under software
control, and it is not memory mapped, so it cannot be read or
written by the software. Its state upon Reset is unknown.
Therefore, if the device is put into the IDLE mode at an
arbitrary time, it will stay in the IDLE mode for somewhere
between 1 and the selected number of instruction cycles.
In order to precisely time the duration of the IDLE state, entry
into the IDLE mode must be synchronized to the state of the
IDLE Timer. The best way to do this is to use the IDLE Timer
interrupt, which occurs on every underflow of the bit of the
IDLE Timer which is associated with the selected window.
Another method is to poll the state of the IDLE Timer pending
bit T0PND, which is set on the same occurrence. The Idle
Timer interrupt is enabled by setting bit T0EN in the ICNTRL
register.
Any time the IDLE Timer window length is changed there is
the possibility of generating a spurious IDLE Timer interrupt
by setting the T0PND bit. The user is advised to disable
IDLE Timer interrupts prior to changing the value of the
ITSEL bits of the ITMR Register and then clear the TOPND
bit before attempting to synchronize operation to the IDLE
Timer.
Note: As with the HALT mode, it is necessary to program two
NOP’s to allow clock resynchronization upon return from the
38
13.4.1.3 HALT Exit Using Reset
A device Reset, which is invoked by a low-level signal on the
RESET input pin, takes the device out of the Dual Clock
mode and puts it into the High Speed mode.
(Continued)
IDLE mode. The NOP’s are placed either at the beginning of
the IDLE Timer interrupt routine or immediately following the
“enter IDLE mode” instruction.
For more information on the IDLE Timer and its associated
interrupt, see the description in section Section 12.1 TIMER
T0 (IDLE TIMER).
13.4.1.4 HALT Exit Using Multi-Input Wake-up
The device can be brought out of the HALT mode by a
transition received on one of the available Wake-up pins.
The pins used and the types of transitions sensed on the
Multi-input pins are software programmable. For information
on programming and using the Multi-Input Wake-up feature,
refer to Section 13.6 MULTI-INPUT WAKE-UP.
13.4 DUAL CLOCK MODE OPERATION
This mode of operation allows for high speed operation of
the Core clock and low speed operation of the Idle Timer.
This mode can be entered from either the High Speed mode
or the Low Speed mode.
A start-up delay is required between the device wake-up and
the execution of program instructions. The start-up delay is
mandatory, and is implemented whether or not the CLKDLY
bit is set. This is because all crystal oscillators and resonators require some time to reach a stable frequency and full
operating amplitude.
If the start-up delay is used, the IDLE Timer (Timer T0)
provides a fixed delay from the time the clock is enabled to
the time the program execution begins. Upon exit from the
HALT mode, the IDLE Timer is enabled with a starting value
of 256 and is decremented with each instruction cycle using
the high speed clock. (The instruction clock runs at one-fifth
the frequency of the high speed oscillatory.) An internal
Schmitt trigger connected to the on-chip CKI inverter ensures that the IDLE Timer is clocked only when the high
speed oscillator has a large enough amplitude. (The Schmitt
trigger is not part of the oscillator closed loop.) When the
IDLE Timer underflows, the clock signals are enabled on the
chip, allowing program execution to proceed. Thus, the delay
is equal to 256 instruction cycles. After exiting HALT, the Idle
Timer will return to being clocked by the low speed clock.
Note: To ensure accurate operation upon start-up of the
device using Multi-input Wake-up, the instruction in the application program used for entering the HALT mode should
be followed by two consecutive NOP (no-operation) instructions.
To enter from the High Speed mode, the following sequence
must be followed:
1. Software sets the LSON bit to 1.
2.
Software waits until the low speed oscillator has stabilized. See Table 3.
3. Software sets the DCEN bit to 1.
To enter from the Low Speed mode, the following sequence
must be followed:
1. Software sets the HSON bit to 1.
2.
Software waits until the high speed oscillator has stabilized. See Table 3, Startup Times.
3. Software clears the CCKSEL bit to 0.
13.4.1 Dual Clock HALT Mode
The fully static architecture of this device allows the state of
the microcontroller to be frozen. This is accomplished by
stopping the high speed clock of the device during the HALT
mode. The processor can be forced to exit the HALT mode
and resume normal operation at any time. The low speed
clock remains on during HALT in the Dual Clock mode.
During normal operation, the actual power consumption depends heavily on the clock speed and operating voltage
used in an application and is shown in the Electrical Specifications. In the HALT mode, the device only draws a small
leakage current, plus current for the BOR feature, plus the
32 kHz oscillator current, plus any current necessary for
driving the outputs. Since total power consumption is affected by the amount of current required to drive the outputs,
all I/Os should be configured to draw minimal current prior to
entering the HALT mode, if possible.
13.4.1.5 Options
This device has two options associated with the HALT mode.
The first option enables the HALT mode feature, while the
second option disables HALT mode operation. Selecting the
disable HALT mode option will cause the microcontroller to
ignore any attempts to HALT the device under software
control. See Section 10.5 OPTION REGISTER for more
details on this option bit.
13.4.1.1 Entering The Dual Clock Halt Mode
The device enters the HALT mode under software control
when the Port G data register bit 7 is set to 1. All processor
action stops in the middle of the next instruction cycle, and
power consumption is reduced to a very low level. In order to
expedite exit from HALT, the low speed oscillator is left
running when the device is Halted in the Dual Clock mode.
However, the Idle Timer will not be clocked.
13.4.2 Dual Clock Idle Mode
In the IDLE mode, program execution stops and power
consumption is reduced to a very low level as with the HALT
mode. However, both oscillators, IDLE Timer (Timer T0), T2
timer (T2HS = 1, T2IDLE = 1), and Clock Monitor continue to
operate, allowing real time to be maintained. The Idle Timer
is clocked by the low speed clock. The device remains idle
for a selected amount of time up to 1 second, and then
automatically exits the IDLE mode and returns to normal
program execution using the high speed clock.
The device is placed in the IDLE mode under software
control by setting the IDLE bit (bit 6 of the Port G data
register).
The IDLE Timer window is selectable from one of five values,
0.125 seconds, 0.25 seconds, 0.5 seconds, 2 second and
2 seconds. Selection of this value is made through the ITMR
register.
13.4.1.2 Exiting The Dual Clock Halt Mode
When the HALT mode is entered by setting bit 7 of the Port
G data register, there is a choice of methods for exiting the
HALT mode: a chip Reset using the RESET pin or a MultiInput Wake-up. The Reset method and Multi-Input Wake-up
method can be used with any clock option.
39
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COP8AME9
13.0 Power Saving Features
COP8AME9
13.0 Power Saving Features
13.5.1 Low Speed HALT Mode
The fully static architecture of this device allows the state of
the microcontroller to be frozen. Because the low speed
oscillator draws very minimal operating current, it will be left
running in the low speed HALT mode. However, the IDLE
Timer will not be running. This also allows for a faster exit
from HALT. The processor can be forced to exit the HALT
mode and resume normal operation at any time.
During normal operation, the actual power consumption depends heavily on the clock speed and operating voltage
used in an application and is shown in the Electrical Specifications. In the HALT mode, the device only draws a small
leakage current, plus current for the BOR feature, plus the
32 kHz oscillator current, plus any current necessary for
driving the outputs. Since total power consumption is affected by the amount of current required to drive the outputs,
all I/Os should be configured to draw minimal current prior to
entering the HALT mode, if possible.
(Continued)
The IDLE mode uses the on-chip IDLE Timer (Timer T0) to
keep track of elapsed time in the IDLE state. The IDLE Timer
runs continuously at the low speed clock rate, whether or not
the device is in the IDLE mode. Each time the bit of the timer
associated with the selected window toggles, the T0PND bit
is set, an interrupt is generated (if enabled), and the device
exits the IDLE mode if in that mode. If the IDLE Timer
interrupt is enabled, the interrupt is serviced before execution of the main program resumes. (However, the instruction
which was started as the part entered the IDLE mode is
completed before the interrupt is serviced. This instruction
should be a NOP which should follow the enter IDLE instruction.) The user must reset the IDLE Timer pending flag
(T0PND) before entering the IDLE mode.
As with the HALT mode, this device can also be returned to
normal operation with a Multi-Input Wake-up input.
13.5.1.1 Entering The Low Speed Halt Mode
The device enters the HALT mode under software control
when the Port G data register bit 7 is set to 1. All processor
action stops in the middle of the next instruction cycle, and
power consumption is reduced to a very low level. In order to
expedite exit from HALT, the low speed oscillator is left
running when the device is Halted in the Low Speed mode.
However, the IDLE Timer will not be clocked.
The IDLE Timer cannot be started or stopped under software
control, and it is not memory mapped, so it cannot be read or
written by the software. Its state upon Reset is unknown.
Therefore, if the device is put into the IDLE mode at an
arbitrary time, it will stay in the IDLE mode for somewhere
between 30 µs and the selected time period.
In order to precisely time the duration of the IDLE state, entry
into the IDLE mode must be ”synchronized to the state of the
IDLE Timer. The best way to do this is to use the IDLE Timer
interrupt, which occurs on every underflow of the bit of the
IDLE Timer which is associated with the selected window.
Another method is to poll the state of the IDLE Timer pending
bit T0PND, which is set on the same occurrence. The Idle
Timer interrupt is enabled by setting bit T0EN in the ICNTRL
register.
Any time the IDLE Timer window length is changed there is
the possibility of generating a spurious IDLE Timer interrupt
by setting the T0PND bit. The user is advised to disable
IDLE Timer interrupts prior to changing the value of the
ITSEL bits of the ITMR Register and then clear the T0PND
bit before attempting to synchronize operation to the IDLE
Timer.
Note: As with the HALT mode, it is necessary to program two
NOP’s to allow clock resynchronization upon return from the
IDLE mode. The NOP’s are placed either at the beginning of
the IDLE Timer interrupt routine or immediately following the
“enter IDLE mode” instruction.
For more information on the IDLE Timer and its associated
interrupt, see the description in the Timers section.
13.5.1.2 Exiting The Low Speed Halt Mode
When the HALT mode is entered by setting bit 7 of the Port
G data register, there is a choice of methods for exiting the
HALT mode: a chip Reset using the RESET pin or a MultiInput Wake-up. The Reset method and Multi-Input Wake-up
method can be used with any clock option, but the availability of the G7 input is dependent on the clock option.
13.5.1.3 HALT Exit Using Reset
A device Reset, which is invoked by a low-level signal on the
RESET input pin, takes the device out of the Low Speed
mode and puts it into the High Speed mode.
13.5.1.4 HALT Exit Using Multi-Input Wake-up
The device can be brought out of the HALT mode by a
transition received on one of the available Wake-up pins.
The pins used and the types of transitions sensed on the
Multi-input pins are software programmable. For information
on programming and using the Multi-Input Wake-up feature,
refer to the Multi-Input Wake-up section.
As the low speed oscillator is left running, there is no start up
delay when exiting the low speed halt mode, regardless of
the state of the CLKDLY bit.
Note: To ensure accurate operation upon start-up of the
device using Multi-Input Wake-up, the instruction in the application program used for entering the HALT mode should
be followed by two consecutive NOP (no-operation) instructions.
13.5 LOW SPEED MODE OPERATION
This mode of operation allows for low speed operation of the
core clock and low speed operation of the Idle Timer. Because the low speed oscillator draws very little operating
current, and also to expedite restarting from HALT mode, the
low speed oscillator is left on at all times in this mode,
including HALT mode. This is the lowest power mode of
operation on the device. This mode can only be entered from
the Dual Clock mode.
To enter the Low Speed mode, the following sequence must
be followed using two separate instructions:
1. Software sets the CCKSEL bit to 1.
2. Software clears the HSON bit to 0.
Since the low speed oscillator is already running, there is no
clock startup delay.
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13.5.1.5 Options
This device has two options associated with the HALT mode.
The first option enables the HALT mode feature, while the
second option disables HALT mode operation. Selecting the
disable HALT mode option will cause the microcontroller to
ignore any attempts to HALT the device under software
control. See the Option section for more details on this
option bit.
40
As with the HALT mode, this device can also be returned to
normal operation with a Multi-Input Wake-up input.
The IDLE Timer cannot be started or stopped under software
control, and it is not memory mapped, so it cannot be read or
written by the software. Its state upon Reset is unknown.
Therefore, if the device is put into the IDLE mode at an
arbitrary time, it will stay in the IDLE mode for somewhere
between 30 µs and the selected time period.
(Continued)
13.5.2 Low Speed Idle Mode
In the IDLE mode, program execution stops and power
consumption is reduced to a very low level as with the HALT
mode. However, the low speed oscillator, IDLE Timer (Timer
T0), and Clock Monitor continue to operate, allowing real
time to be maintained. The device remains IDLE for a selected amount of time up to 2 seconds, and then automatically exits the IDLE mode and returns to normal program
execution using the low speed clock.
In order to precisely time the duration of the IDLE state, entry
into the IDLE mode must be synchronized to the state of the
IDLE Timer. The best way to do this is to use the IDLE Timer
interrupt, which occurs on every underflow of the bit of the
IDLE Timer which is associated with the selected window.
Another method is to poll the state of the IDLE Timer pending
bit T0PND, which is set on the same occurrence. The Idle
Timer interrupt is enabled by setting bit T0EN in the ICNTRL
register.
Any time the IDLE Timer window length is changed there is
the possibility of generating a spurious IDLE Timer interrupt
by setting the T0PND bit. The user is advised to disable
IDLE Timer interrupts prior to changing the value of the
ITSEL bits of the ITMR Register and then clear the T0PND
bit before attempting to synchronize operation to the IDLE
Timer.
As with the HALT mode, it is necessary to program two
NOP’s to allow clock resynchronization upon return from the
IDLE mode. The NOP’s are placed either at the beginning of
the IDLE Timer interrupt routine or immediately following the
“enter IDLE mode” instruction.
For more information on the IDLE Timer and its associated
interrupt, see the description in Section 12.1 TIMER T0
(IDLE TIMER).
The device is placed in the IDLE mode under software
control by setting the IDLE bit (bit 6 of the Port G data
register).
The IDLE Timer window is selectable from one of five values,
0.125 seconds, 0.25 seconds, 0.5 seconds, 1 second, and
2 seconds. Selection of this value is made through the ITMR
register.
The IDLE mode uses the on-chip IDLE Timer (Timer T0) to
keep track of elapsed time in the IDLE state. The IDLE Timer
runs continuously at the low speed clock rate, whether or not
the device is in the IDLE mode. Each time the bit of the timer
associated with the selected window toggles, the T0PND bit
is set, an interrupt is generated (if enabled), and the device
exits the IDLE mode if in that mode. If the IDLE Timer
interrupt is enabled, the interrupt is serviced before execution of the main program resumes. (However, the instruction
which was started as the part entered the IDLE mode is
completed before the interrupt is serviced. This instruction
should be a NOP which should follow the enter IDLE instruction.) The user must reset the IDLE Timer pending flag
(T0PND) before entering the IDLE mode.
20006324
FIGURE 20. Multi-Input Wake-Up Logic
41
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COP8AME9
13.0 Power Saving Features
COP8AME9
13.0 Power Saving Features
be set or reset for the desired edge selects, followed by the
associated WKPND bits being cleared.
(Continued)
This same procedure should be used following reset, since
the L port inputs are left floating as a result of reset.
The occurrence of the selected trigger condition for MultiInput Wake-up is latched into a pending register called
WKPND. The respective bits of the WKPND register will be
set on the occurrence of the selected trigger edge on the
corresponding Port L pin. The user has the responsibility of
clearing these pending flags. Since WKPND is a pending
register for the occurrence of selected wake-up conditions,
the device will not enter the HALT mode if any Wake-up bit is
both enabled and pending. Consequently, the user must
clear the pending flags before attempting to enter the HALT
mode.
13.6 MULTI-INPUT WAKE-UP
The Multi-Input Wake-up feature is used to return (wake-up)
the device from either the HALT or IDLE modes. Alternately
Multi-Input Wake-up/Interrupt feature may also be used to
generate up to 8 edge selectable external interrupts.
Figure 20 shows the Multi-Input Wake-up logic.
The Multi-Input Wake-up feature utilizes the L Port. The user
selects which particular L port bit (or combination of L Port
bits) will cause the device to exit the HALT or IDLE modes.
The selection is done through the register WKEN. The register WKEN is an 8-bit read/write register, which contains a
control bit for every L port bit. Setting a particular WKEN bit
enables a Wake-up from the associated L port pin.
The user can select whether the trigger condition on the
selected L Port pin is going to be either a positive edge (low
to high transition) or a negative edge (high to low transition).
This selection is made via the register WKEDG, which is an
8-bit control register with a bit assigned to each L Port pin.
Setting the control bit will select the trigger condition to be a
negative edge on that particular L Port pin. Resetting the bit
selects the trigger condition to be a positive edge. Changing
an edge select entails several steps in order to avoid a
Wake-up condition as a result of the edge change. First, the
associated WKEN bit should be reset, followed by the edge
select change in WKEDG. Next, the associated WKPND bit
should be cleared, followed by the associated WKEN bit
being re-enabled.
An example may serve to clarify this procedure. Suppose we
wish to change the edge select from positive (low going high)
to negative (high going low) for L Port bit 5, where bit 5 has
previously been enabled for an input interrupt. The program
would be as follows:
RBIT 5, WKEN
; Disable MIWU
SBIT 5, WKEDG ; Change edge polarity
RBIT 5, WKPND ; Reset pending flag
SBIT 5, WKEN
; Enable MIWU
If the L port bits have been used as outputs and then
changed to inputs with Multi-Input Wake-up/Interrupt, a
safety procedure should also be followed to avoid wake-up
conditions. After the selected L port bits have been changed
from output to input but before the associated WKEN bits are
enabled, the associated edge select bits in WKEDG should
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WKEN and WKEDG are all read/write registers, and are
cleared at reset. WKPND register contains random value
after reset.
14.0 USART
The device contains a full-duplex software programmable
USART. The USART (Figure 21) consists of a transmit shift
register, a receive shift register and seven addressable registers, as follows: a transmit buffer register (TBUF), a receiver buffer register (RBUF), a USART control and status
register (ENU), a USART receive control and status register
(ENUR), a USART interrupt and clock source register
(ENUI), a prescaler select register (PSR) and baud (BAUD)
register. The ENU register contains flags for transmit and
receive functions; this register also determines the length of
the data frame (7, 8 or 9 bits), the value of the ninth bit in
transmission, and parity selection bits. The ENUR register
flags framing, data overrun, parity errors and line breaks
while the USART is receiving.
Other functions of the ENUR register include saving the
ninth bit received in the data frame, enabling or disabling the
USART’s attention mode of operation and providing additional receiver/transmitter status information via RCVG and
XMTG bits. The determination of an internal or external clock
source is done by the ENUI register, as well as selecting the
number of stop bits and enabling or disabling transmit and
receive interrupts. A control flag in this register can also
select the USART mode of operation: asynchronous or
synchronous.
42
COP8AME9
14.0 USART
(Continued)
20006325
FIGURE 21. USART Block Diagram
PEN: This bit enables/disables Parity (7- and 8-bit modes
only). Read/Write, cleared on reset.
PEN = 0
Parity disabled.
PEN = 1
Parity enabled.
14.1 USART CONTROL AND STATUS REGISTERS
The operation of the USART is programmed through three
registers: ENU, ENUR and ENUI.
14.2 DESCRIPTION OF USART REGISTER BITS
ENU — USART CONTROL AND STATUS REGISTER (Address at 0BA)
PEN
PSEL1
XBIT9/
CHL1
CHL0
ERR
RBFL
PSEL1, PSEL0: Parity select bits. Read/Write, cleared on
reset.
PSEL1 = 0, PSEL0 = 0
Odd Parity (if Parity enabled)
PSEL1 = 0, PSEL1 = 1
Even Parity (if Parity enabled)
PSEL1 = 1, PSEL0 = 0
Mark(1) (if Parity enabled)
PSEL1 = 1, PSEL1 = 1
Space(0) (if Parity enabled)
TBMT
PSEL0
Bit 7
Bit 0
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COP8AME9
14.0 USART
XMTG: This bit is set to indicate that the USART is transmitting. It gets reset at the end of the last frame (end of last Stop
bit). Read only, cleared on reset.
(Continued)
XBIT9/PSEL0: Programs the ninth bit for transmission when
the USART is operating with nine data bits per frame. For
seven or eight data bits per frame, this bit in conjunction with
PSEL1 selects parity. Read/Write, cleared on reset.
CHL1, CHL0: These bits select the character frame format.
Parity is not included and is generated/verified by hardware.
Read/Write, cleared on reset.
CHL1 = 0, CHL0 = 0
The frame contains eight data bits.
CHL1 = 0, CHL0 = 1
CHL1 = 1, CHL0 = 0
The frame contains seven data bits.
The frame contains nine data bits.
CHL1 = 1, CHL0 = 1
Loopback Mode selected. Transmitter output internally looped back
to receiver input. Nine bit framing
format is used.
RCVG: This bit is set high whenever a framing error or a
Break Detect occurs and goes low when RDX goes high.
Read only, cleared on reset.
ENUI — USART INTERRUPT AND CLOCK SOURCE REGISTER (Address at 0BC)
STP2
PE
BD
RBIT9
ATTN
ERI
ETI
Bit 0
SSEL: USART mode select. Read only, cleared on reset.
SSEL = 0
Asynchronous Mode.
SSEL = 1
Synchronous Mode.
XRCLK: This bit selects the clock source for the receiver
section. Read/Write, cleared on reset.
XRCLK = 0
The clock source is selected through the
PSR and BAUD registers.
XRCLK = 1
Signal on CKX (L1) pin is used as the clock.
XTCLK: This bit selects the clock source for the transmitter
section. Read/Write, cleared on reset.
XTCLK = 0
The clock source is selected through the PSR
and BAUD registers.
XMTG RCVG
Bit 0
XTCLK = 1
DOE: Flags a Data Overrun Error. Read only, cleared on
read, cleared on reset.
DOE = 0
Indicates no Data Overrun Error has been detected since the last time the ENUR register
was read.
DOE = 1
Indicates the occurrence of a Data Overrun
Error.
Signal on CKX (L1) pin is used as the clock.
ERI: This bit enables/disables interrupt from the receiver
section. Read/Write, cleared on reset.
ERI = 0
Interrupt from the receiver is disabled.
ERI = 1
Interrupt from the receiver is enabled.
ETI: This bit enables/disables interrupt from the transmitter
section. Read/Write, cleared on reset.
ETI = 0
Interrupt from the transmitter is disabled.
ETI = 1
Interrupt from the transmitter is enabled.
FE: Flags a Framing Error. Read only, cleared on read,
cleared on reset.
FE = 0
Indicates no Framing Error has been detected
since the last time the ENUR register was read.
FE = 1
Indicates the occurrence of a Framing Error.
14.3 ASSOCIATED I/O PINS
Data is transmitted on the TDX pin and received on the RDX
pin. TDX is the alternate function assigned to Port L pin L2;
it is selected by setting ETDX (in the ENUI register) to one.
RDX is an inherent function Port L pin L3, requiring no setup.
Port L pin L2 must be configured as an output in the Port L
Configuration Register in order to be used as the TDX pin.
The baud rate clock for the USART can be generated onchip, or can be taken from an external source. Port L pin L1
(CKX) is the external clock I/O pin. The CKX pin can be
either an input or an output, as determined by Port L Configuration and Data registers (Bit 1). As an input, it accepts a
clock signal which may be selected to drive the transmitter
and/or receiver. As an output, it presents the internal Baud
Rate Generator output.
Note: The CKX pin is unavailable if Port L1 is used for the
Low Speed Oscillator.
PE: Flags a Parity Error. Read only, cleared on read, cleared
on reset.
PE = 0
Indicates no Parity Error has been detected since
the last time the ENUR register was read.
PE = 1
Indicates the occurrence of a Parity Error.
BD: Flags a line break.
BD = 0 Indicates no Line Break has been detected since
the last time the ENUR register was read.
BD = 1 Indicates the occurrence of a Line Break.
RBIT9: Contains the ninth data bit received when the
USART is operating with nine data bits per frame. Read only,
cleared on reset.
ATTN: ATTENTION Mode is enabled while this bit is set.
This bit is cleared automatically on receiving a character with
data bit nine set. Read/Write, cleared on reset.
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XRCLK XTCLK
ETDX: TDX (USART Transmit Pin) is the alternate function
assigned to Port L pin L2; it is selected by setting ETDX bit.
TBMT: This bit is set when the USART transfers a byte of
data from the TBUF register into the TSFT register for transmission. It is automatically reset when software writes into
the TBUF register. Read only, bit is set to “one” on reset; it
cannot be written by software.
ENUR — USART RECEIVE CONTROL AND STATUS REGISTER (Address at 0BB)
FE
SSEL
BRK: Holds TDX (USART Transmit Pin) low to generate a
Line Break. Timing of the Line Break is under software
control.
RBFL: This bit is set when the USART has received a
complete character and has copied it into the RBUF register.
It is automatically reset when software reads the character
from RBUF. Read only; it cannot be written by software,
cleared on reset.
DOE
ETDX
STP2: This bit programs the number of Stop bits to be
transmitted. Read/Write, cleared on reset.
STP2 = 0
One Stop bit transmitted.
STP2 = 1
Two Stop bits transmitted.
ERR: This bit is a global USART error flag which gets set if
any or a combination of the errors (DOE, FE, PE, BO) occur.
Read only; it cannot be written by software, cleared on reset.
Bit 7
BRK
Bit 7
44
The USART has two modes of operation: asynchronous
mode and synchronous mode.
If data transmit and receive are selected with the CKX pin as
clock output, the device generates the synchronous clock
output at the CKX pin. The internal baud rate generator is
used to produce the synchronous clock. Data transmit and
receive are performed synchronously with this clock.
14.4.1 Asynchronous Mode
14.5 FRAMING FORMATS
This mode is selected by resetting the SSEL (in the ENUI
register) bit to zero. The input frequency to the USART is
16 times the baud rate.
The USART supports several serial framing formats (Figure
22). The format is selected using control bits in the ENU,
ENUR and ENUI registers.
The TSFT and TBUF registers double-buffer data for transmission. While TSFT is shifting out the current character on
the TDX pin, the TBUF register may be loaded by software
with the next byte to be transmitted. When TSFT finishes
transmitting the current character the contents of TBUF are
transferred to the TSFT register and the Transmit Buffer
Empty Flag (TBMT in the ENU register) is set. The TBMT
flag is automatically reset by the USART when software
loads a new character into the TBUF register. There is also
the XMTG bit which is set to indicate that the USART is
transmitting. This bit gets reset at the end of the last frame
(end of last Stop bit). TBUF is a read/write register.
The first format (1, 1a, 1b, 1c) for data transmission (CHL0 =
1, CHL1 = 0) consists of Start bit, seven Data bits (excluding
parity) and one or two Stop bits. In applications using parity,
the parity bit is generated and verified by hardware.
(Continued)
14.4 USART OPERATION
The second format (CHL0 = 0, CHL1 = 0) consists of one
Start bit, eight Data bits (excluding parity) and one or two
Stop bits. Parity bit is generated and verified by hardware.
The third format for transmission (CHL0 = 0, CHL1 = 1)
consists of one Start bit, nine Data bits and one or two Stop
bits. This format also supports the USART “ATTENTION”
feature. When operating in this format, all eight bits of TBUF
and RBUF are used for data. The ninth data bit is transmitted
and received using two bits in the ENU and ENUR registers,
called XBIT9 and RBIT9. RBIT9 is a read only bit. Parity is
not generated or verified in this mode.
The parity is enabled/disabled by PEN bit located in the ENU
register. Parity is selected for 7- and 8-bit modes only. If
parity is enabled (PEN = 1), the parity selection is then
performed by PSEL0 and PSEL1 bits located in the ENU
register.
Note that the XBIT9/PSEL0 bit located in the ENU register
serves two mutually exclusive functions. This bit programs
the ninth bit for transmission when the USART is operating
with nine data bits per frame. There is no parity selection in
this framing format. For other framing formats XBIT9 is not
needed and the bit is PSEL0 used in conjunction with PSEL1
to select parity.
The frame formats for the receiver differ from the transmitter
in the number of Stop bits required. The receiver only requires one Stop bit in a frame, regardless of the setting of the
Stop bit selection bits in the control register. Note that an
implicit assumption is made for full duplex USART operation
that the framing formats are the same for the transmitter and
receiver.
The RSFT and RBUF registers double-buffer data being
received. The USART receiver continually monitors the signal on the RDX pin for a low level to detect the beginning of
a Start bit. Upon sensing this low level, it waits for half a bit
time and samples again. If the RDX pin is still low, the
receiver considers this to be a valid Start bit, and the remaining bits in the character frame are each sampled three times
around the center of the bit time. Serial data input on the
RDX pin is shifted into the RSFT register. Upon receiving the
complete character, the contents of the RSFT register are
copied into the RBUF register and the Received Buffer Full
Flag (RBFL) is set. RBFL is automatically reset when software reads the character from the RBUF register. RBUF is a
read only register. There is also the RCVG bit which is set
high when a framing error or break detect occurs and goes
low once RDX goes high.
14.4.2 Synchronous Mode
In this mode data is transferred synchronously with the
clock. Data is transmitted on the rising edge and received on
the falling edge of the synchronous clock.
This mode is selected by setting SSEL bit in the ENUI
register. The input frequency to the USART is the same as
the baud rate.
When an external clock input is selected at the CKX pin, data
transmit and receive are performed synchronously with this
clock through TDX/RDX pins.
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COP8AME9
14.0 USART
COP8AME9
14.0 USART
(Continued)
20006326
FIGURE 22. Framing Formats
14.6 USART INTERRUPTS
The USART is capable of generating interrupts. Interrupts
are generated on Receive Buffer Full and Transmit Buffer
Empty. Both interrupts have individual interrupt vectors. Two
bytes of program memory space are reserved for each interrupt vector. The two vectors are located at addresses
0xEC to 0xEF Hex in the program memory space. The
interrupts can be individually enabled or disabled using Enable Transmit Interrupt (ETI) and Enable Receive Interrupt
(ERI) bits in the ENUI register.
The interrupt from the Transmitter is set pending, and remains pending, as long as both the TBMT and ETI bits are
set. To remove this interrupt, software must either clear the
ETI bit or write to the TBUF register (thus clearing the TBMT
bit).
The interrupt from the receiver is set pending, and remains
pending, as long as both the RBFL and ERI bits are set. To
remove this interrupt, software must either clear the ERI bit
or read from the RBUF register (thus clearing the RBFL bit).
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14.7 BAUD CLOCK GENERATION
The clock inputs to the transmitter and receiver sections of
the USART can be individually selected to come either from
an external source at the CKX pin (port L, pin L1) or from a
source selected in the PSR and BAUD registers. Internally,
the basic baud clock is created from the MCLK through a
two-stage divider chain consisting of a 1-16 (increments of
0.5) prescaler and an 11-bit binary counter (Figure 23). The
divide factors are specified through two read/write registers
shown in Figure 24. Note that the 11-bit Baud Rate Divisor
spills over into the Prescaler Select Register (PSR). PSR is
cleared upon reset.
As shown in Table 20, a Prescaler Factor of 0 corresponds to
NO CLOCK. This condition is the USART power down mode
where the USART clock is turned off for power saving purpose. The user must also turn the USART clock off when a
different baud rate is chosen.
The correspondences between the 5-bit Prescaler Select
and Prescaler factors are shown in Table 20. There are
46
(Continued)
many ways to calculate the two divisor factors, but one
particularly effective method would be to achieve a 1.8432
MHz frequency coming out of the first stage. The 1.8432
MHz prescaler output is then used to drive the software
programmable baud rate counter to create a 16x clock for
the following baud rates: 110, 134.5, 150, 300, 600, 1200,
1800, 2400, 3600, 4800, 7200, 9600, 19200 and 38400
(Table 19). Other baud rates may be created by using appropriate divisors. The 16x clock is then divided by 16 to
provide the rate for the serial shift registers of the transmitter
and receiver.
TABLE 19. Baud Rate Divisors
(1.8432 MHz Prescaler Output)
Prescaler
Prescaler
Select
Factor
01000
4.5
01001
5
01010
5.5
01011
6
01100
6.5
01101
7
01110
7.5
01111
8
10000
8.5
10001
9
10010
9.5
Baud Rate
10011
10
Divisor − 1 (N-1)
10100
10.5
110 (110.03)
1046
10101
11
134.5 (134.58)
855
10110
11.5
150
767
10111
12
300
383
11000
12.5
600
191
11001
13
1200
95
11010
13.5
1800
63
11011
14
2400
47
11100
14.5
3600
31
11101
15
4800
23
11110
15.5
7200
15
11111
16
9600
11
19200
5
38400
2
Baud Rate
As an example, considering Asynchronous Mode and a crystal frequency of 4.608 MHz, the prescaler factor selected is:
(4.608 x 2)/1.8432 = 5
The 5 entry is available in Table 20. The 1.8432 MHz prescaler output is then used with proper Baud Rate Divisor
(Table 19) to obtain different baud rates. For a baud rate of
19200 e.g., the entry in Table 19 is 5.
N − 1 = 5 (N − 1 is the value from Table 19)
Note: The entries in Table 19 assume a prescaler output of 1.8432 MHz. In
asynchronous mode the baud rate could be as high as 625k.
N = 6 (N is the Baud Rate Divisor)
Baud Rate = 1.8432 MHz/(16 x 6) = 19200
The divide by 16 is performed because in the asynchronous
mode, the input frequency to the USART is 16 times the
baud rate. The equation to calculate baud rates is given
below.
The actual Baud Rate may be found from:
BR = (FC x 2)/(16 x N x P)
20006327
FIGURE 23. USART BAUD Clock Generation
TABLE 20. Prescaler Factors
Prescaler
Where:
BR is the Baud Rate
FC is the crystal frequency
N is the Baud Rate Divisor (Table 19)
P is the Prescaler Divide Factor selected by the value in the
Prescaler Select Register (Table 20)
Note: In the Synchronous Mode, the divisor 16 is replaced
by two.
Example:
Asynchronous Mode:
Crystal Frequency = 5 MHz
Desired baud rate = 19200
Prescaler
Select
Factor
00000
NO CLOCK
00001
1
00010
1.5
00011
2
00100
2.5
00101
3
00110
3.5
00111
4
COP8AME9
14.0 USART
47
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COP8AME9
14.0 USART
N = 32.552/6.5 = 5.008 (N = 5)
The programmed value (from Table 19) should be 4 (N - 1).
(Continued)
Using the above equation N x P can be calculated first.
Using the above values calculated for N and P:
BR = (5 x 106 x 2)/(16 x 5 x 6.5) = 19230.769
N x P = (5 x 106 x 2)/(16 x 19200) = 32.552
Now 32.552 is divided by each Prescaler Factor (Table 20) to
obtain a value closest to an integer. This factor happens to
be 6.5 (P = 6.5).
error = (19230.769 - 19200) x 100/19200 = 0.16%
20006328
FIGURE 24. USART BAUD Clock Divisor Registers
14.8 EFFECT OF HALT/IDLE
The USART logic is reinitialized when either the HALT or
IDLE modes are entered. This reinitialization sets the TBMT
flag and resets all read only bits in the USART control and
status registers. Read/Write bits remain unchanged. The
Transmit Buffer (TBUF) is not affected, but the Transmit Shift
register (TSFT) bits are set to one. The receiver registers
RBUF and RSFT are not affected.
The device will exit from the HALT/IDLE modes when the
Start bit of a character is detected at the RDX (L3) pin. This
feature is obtained by using the Multi-Input Wake-up scheme
provided on the device.
Before entering the HALT or IDLE modes the user program
must select the Wake-up source to be on the RDX pin. This
selection is done by setting bit 3 of WKEN (Wake-up Enable)
register. The Wake-up trigger condition is then selected to be
high to low transition. This is done via the WKEDG register
(Bit 3 is one).
If the device is halted and crystal oscillator is used, the
Wake-up signal will not start the chip running immediately
because of the finite start up time requirement of the crystal
oscillator. The IDLE timer (T0) generates a fixed (256 tC)
delay to ensure that the oscillator has indeed stabilized
before allowing the device to execute code. The user has to
consider this delay when data transfer is expected immediately after exiting the HALT mode.
14.10 ATTENTION MODE
The USART Receiver section supports an alternate mode of
operation, referred to as ATTENTION Mode. This mode of
operation is selected by the ATTN bit in the ENUR register.
The data format for transmission must also be selected as
having nine Data bits and either one or two Stop bits.
The ATTENTION mode of operation is intended for use in
networking the device with other processors. Typically in
such environments the messages consists of device addresses, indicating which of several destinations should receive them, and the actual data. This Mode supports a
scheme in which addresses are flagged by having the ninth
bit of the data field set to a 1. If the ninth bit is reset to a zero
the byte is a Data byte.
While in ATTENTION mode, the USART monitors the communication flow, but ignores all characters until an address
character is received. Upon receiving an address character,
the USART signals that the character is ready by setting the
RBFL flag, which in turn interrupts the processor if USART
Receiver interrupts are enabled. The ATTN bit is also cleared
automatically at this point, so that data characters as well as
address characters are recognized. Software examines the
contents of the RBUF and responds by deciding either to
accept the subsequent data stream (by leaving the ATTN bit
reset) or to wait until the next address character is seen (by
setting the ATTN bit again).
Operation of the USART Transmitter is not affected by selection of this Mode. The value of the ninth bit to be transmitted is programmed by setting XBIT9 appropriately. The
value of the ninth bit received is obtained by reading RBIT9.
Since this bit is located in ENUR register where the error
flags reside, a bit operation on it will reset the error flags.
14.9 DIAGNOSTIC
Bits CHL0 and CHL1 in the ENU register provide a loopback
feature for diagnostic testing of the USART. When both bits
are set to one, the following occurs: The receiver input pin
(RDX) is internally connected to the transmitter output pin
(TDX); the output of the Transmitter Shift Register is “looped
back” into the Receive Shift Register input. In this mode,
data that is transmitted is immediately received. This feature
allows the processor to verify the transmit and receive data
paths of the USART.
Note that the framing format for this mode is the nine bit
format; one Start bit, nine data bits, and one or two Stop bits.
Parity is not generated or verified in this mode.
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14.11 BREAK GENERATION
To generate a line break, the user software should set the
BRK bit in the ENUI register. This will force the TDX pin to 0
and hold it there until the BRK bit is reset.
48
This device contains a 7-channel, multiplexed input, successive approximation, 10-bit Analog-to-Digital Converter with
Programmable Gain Amplifier. One A/D channel is internally
connected to the temperature sensor. The remaining six
channels are connected to pins B2-B7 and are available
external to the device. Pins AVCC and AGND are used for the
15.1 9.1 OPERATING MODES
The simplified block diagram of the A/D Converter is shown
in Figure 25.
20006355
FIGURE 25. Simplified A/D Converter Block Diagram
The A/D Converter supports both Single Ended and Differential modes of operation. Differential mode is only supported when the programmable gain amplifier is bypassed.
Two specific analog channel selection modes are supported.
These are as follows:
1. Allow any specific channel, except for the temperature
sensor input, with or without the programmable gain
amplifier, to be selected at one time. The A/D Converter
performs the specific conversion requested and stops.
When using the temperature sensor, the programmable
gain amplifier is required. See the Temperature Sensor
section for more details on using the temperature sensor.
2. Allow any differential channel pair to be selected at one
time. The A/D Converter performs the specific differential conversion requested and stops. Differential mode is
only supported when the programmable gain amplifier is
bypassed.
In both Single Ended mode and Differential mode, there is
the capability to connect the analog multiplexor output, with
the exception of the temperature sensor input, and A/D
converter input to external pins. This provides the ability to
externally connect a common filter/signal conditioning circuit
for the A/D Converter.
The A/D Converter is supported by six memory mapped
registers: two result registers, the control register, two offset
trimming registers, and the gain register. When the device is
reset, the mode control register (ENAD) is cleared, the A/D is
powered down and the A/D result registers have unknown
data. The offset trim registers are also initialized to 40 Hex
on Reset and need to be re-trimmed, if being used. The gain
register is initialized to 00 on Reset.
15.1.1 A/D Control Register
The control register, ENAD contains 4 bits for channel selection, 1 bit for mode selection, 1 bit for the multiplexor
output selection, 1 bit for prescaler selection, and a Busy bit.
An A/D conversion is initiated by setting the ADBSY bit in the
ENAD control register. The result of the conversion is available to the user in the A/D result registers, ADRSTH and
ADRSTL, when ADBSY is cleared by the hardware on
completion of the conversion.
TABLE 21. ENAD Register
Bit 7
Bit 6
Bit 5
Bit 4
Channel Select
ADCH3
ADCH2
ADCH1
Bit 3
Mode
Select
ADCH0
ADMOD
Bit 2
Bit 1
Mux/Out Prescale
MUX
PSC
Bit 0
Busy
ADBSY
15.1.1.1 Channel Select
This 4-bit field selects one of seven channels to be the VIN+.
The mode selection and the mux output determine the VINinput. When MUX = 0, all seven channels are available, as
shown in Table 22. When MUX = 1, only 4 channels are
available, as shown in Table 23.
49
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COP8AME9
A/D Converter, Temperature Sensor, Programmable Gain
Amplifier, and Stand-Alone Amplifier.
15.0 A/D Converter
COP8AME9
15.0 A/D Converter
(Continued)
TABLE 22. A/D Converter Channel Selection when the Multiplexor Output is Disabled
Select Bits
Mode Select
ADMOD = 0
Single Ended
Mode
Mode Select
ADMOD = 1
Differential
Mode
Mux Output
Disabled
ADCH3
ADCH2
ADCH1
ADCH0
Channel No.
Channel Pairs
(+, −)
MUX
0
1
1
1
Temp sensor, if
enabled
Not used
0
1
0
1
0
10
10, 11 (Note 12)
0
1
0
1
1
11
11, 10 (Note 12)
0
1
1
0
0
12
12, 13 (Note 12)
0
1
1
0
1
13
13, 12 (Note 12)
0
1
1
1
0
14
14, 15 (Note 12)
0
1
1
1
1
15
15, 14 (Note 12)
0
Note 12: Only if the programmable gain amplifier is bypassed.
15.1.1.2 Multiplexor Output Select
The MUX bit field allows the output of the A/D multiplexor
(with the exception of the temperature sensor channel) and
the input to the A/D to be connected directly to external pins.
This allows for an external, common filter/signal conditioning
circuit to be applied to all channels. The output of the external conditioning circuit can then be connected directly to the
input of the Sample and Hold input on the A/D Converter.
See Figure 26 for the single ended mode diagram. The
Multiplexor output is connected to ADCH4 and the A/D input
is connected to ADCH5. For differential mode, the differential
multiplexor outputs are available and should be converted to
a single ended voltage for connection to the A/D Converter
Input. The programmable gain amplifier must be bypassed
when using the multiplexor output feature in differential
mode. See Figure 27.
3.
Select the same desired channel and operating modes
used in step 1 and load them into ENAD and also set
ADBSY. This will start the conversion.
4. After conversion is completed, obtain the results from
the result registers.
20006356
The channel assignments for this mode are shown in Table
23.
FIGURE 26. A/D with Single Ended Mux Output Feature
Enabled
When using the Mux Output feature, the delay though the
internal multiplexor to the pin, plus the delay of the external
filter circuit, plus the internal delay to the Sample and Hold
will exceed the three clock cycles that’s allowed in the conversion. This requires that whenever the MUX bit = 1, that
the channel selected by ADCH3:0 bits, be enabled, even
when ADBSY = 0, and gated to the mux output pin. The input
path to the A/D converter should also be enabled. This
allows the input channel to be selected and settled before
starting a conversion. The sequence to perform conversions
using the Mux Out feature is a multistep process and is listed
below.
1. Select the desired channel, excluding the temperature
sensor channel, and operating modes and load them
into ENAD without setting ADBSY.
2. Wait the appropriate time until the analog input has
settled. This will depend on the application and the
response of the external circuit.
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20006357
FIGURE 27. A/D with Differential Mux Output Feature
Enabled
50
(Continued)
TABLE 23. A/D Converter Channel Selection when the Multiplexor Output is Enabled
Select Bits
Mode Select
ADMOD = 0
Single Ended Mode
Mode Select
ADMOD = 1
Differential Mode
Mux Output
Enabled
ADCH3
ADCH2
ADCH1
ADCH0
Channel No.
Channel Pairs (+, −)
MUX
0
1
1
1
Temp Sensor (Note 14)
Not used
1
1
0
0
0
Not used
Not used
1
1
0
0
1
Not used
Not used
1
1
0
1
0
10
10, 11 (Note 15)
1
1
0
1
1
11
11, 10 (Note 15)
1
1
1
0
0
12
Not Used
1
1
1
0
1
13
ADCH13 is
Mux Output −
(Notes 13, 15)
1
1
1
1
0
ADCH14 is
Mux Output
(Note 13)
ADCH14 is
Mux Output +
(Notes 13, 15)
1
1
1
1
1
ADCH15 is
A/D Input
(Note 13)
ADCH15 is
A/D Input
(Notes 13, 15)
1
Note 13: These input channels are not available in this mode.
Note 14: Temperature Sensor cannot be used in this mode.
Note 15: Programmable Gain Amplifier must be bypassed when MUX = 1.
values currently in the ENAD register. Normal completion of
an A/D conversion clears the ADBSY bit and turns off the A/D
Converter.
When changing the channel and gain of the programmable
gain amplifier, it is necessary to wait before performing an
A/D conversion. This due to the amplifier settling time. See
the section on the Programmable Gain Amplifier for these
settling times.
If the user wishes to restart a conversion which is already in
progress, this can be accomplished only by writing a zero to
the ADBSY bit to stop the current conversion and then by
writing a one to ADBSY to start a new conversion. This can
be done in two consecutive instructions.
All multiplexor input channels should be internally gated off
when ADBSY = 0, unless MUX =1 or the programmable gain
amplifier is enabled. When MUX =1 or the programmable
gain amplifier is enabled, the internal path through the multiplexor to the pin and the input path for the A/D Converter
should be enabled.
15.1.1.3 Mode Select
This 1-bit field is used to select the mode of operation (single
ended or differential) as shown in the following Table 24.
TABLE 24. A/D Conversion Mode Selection
ADMOD
Mode
0
Single Ended mode. This mode is required if
the temperature sensor is being selected.
1
Differential mode (programmable gain
amplifier must be bypassed)
15.1.1.4 Prescaler Select
This 1-bit field is used to select one of two prescaler clocks
for the A/D Converter. The following Table 25 shows the
various prescaler options. Care must be taken, when selecting this bit, to not exceed the maximum frequency of the A/D
converter.
15.1.2 A/D Result Registers
There are two result registers for the A/D converter: the high
8 bits of the result and the low 2-bits of the result. The format
of these registers is shown in Tables 26, 27. Both registers
are read/write registers, but in normal operation, the hardware writes the value into the register when the conversion is
complete and the software reads the value. Both registers
are undefined upon Reset. They hold the previous value until
a new conversion overwrites them. When reading ADRSTL,
bits 5-0 will read as 0.
TABLE 25. A/D Converter Clock Prescale
PSC
Clock Select
0
MCLK Divide by 1
1
MCLK Divide by 16
15.1.1.5 Busy Bit
The ADBSY bit of the ENAD register is used to control
starting and stopping of the A/D conversion. When ADBSY is
cleared, the prescale logic is disabled and the A/D clock is
turned off, drawing minimal power. Setting the ADBSY bit
starts the A/D clock and initiates a conversion based on the
51
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15.0 A/D Converter
COP8AME9
15.0 A/D Converter
TABLE 28. ADGAIN
(Continued)
TABLE 26. ADRSTH
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 9
Bit 8
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 1
Bit 0
0
0
0
0
0
0
Bit 7
Bit 6
Bit 5
ENAMP1
ENTS
TRIM
Bit 4
Bit 3
Reserved
Bit 2
Bit 1
Bit 0
GAIN2 GAIN1 GAIN0
ENAMP1 Enables stand-alone amplifier (AMP1) to port B.
Enabled = 1. Disabled =0.
TABLE 27. ADRSTL
ENTS
Enable internal temperature sensor. Enabled =
1. Disabled = 0.
TRIM
Configures the programmable gain amplifier into
the trimming configuration by shorting its + and −
inputs together. Enabled = 1. Disabled = 0. This
bit should be set to 0 for normal use of the
programmable gain amplifier.
GAIN2:0
Controls the gain of the programmable gain amplifier. See Table 29. When performing a conversion on the temperature sensor, a gain of 1 or 2
must be selected, depending on the operating
voltage of the device. A gain of 2 can only be
used for the temperature sensor if VCC ≥ 4.5V.
15.2 PROGRAMMABLE GAIN AMPLIFIER
A programmable gain amplifier is located between the analog multiplexor and the input to the A/D. It supports single
ended mode only. The gain of this amplifier is selected by the
ADGAIN register shown in Table 28. This register is also
used to enable the stand-alone amplifier (AMP1) on port pins
B3, B4 and B5, the internal temperature sensor, and the
offset trimming configuration. Both the stand-alone amplifier
and the programmable gain amplifier will draw DC current
when enabled. To minimize the amount of current drawn in
the HALT mode, the user should disable both amplifiers
before entering HALT. This register is initialized to 00h on
Reset.
Reserved These bits are reserved and must be 0.
TABLE 29. Gain Bit Assignments
TRIM
GAIN2
GAIN1
GAIN0
Gain Tolerance
0
0
0
0
Not Applicable
0
0
0
1
0
0
1
0
0
0
1
1
0
1
0
0
0
1
0
1
0
1
1
0
0
1
1
1
±
±
±
±
±
±
±
1
X
X
X
N/A
15.2.1 Programmable Gain Amplifier Settling Time
When changing channels or the gain, it’s necessary to give
the programmable gain amplifier time to settle before performing an A/D conversion. This is because the input from
the previous channel could have the amplifier output near
one power supply rail and the newly selected channel or gain
may need to drive the output to the other power supply rail.
The amount of settling time is based on the gain of the
amplifier. See Table 30. It is recommended that the user wait
7.6 time constants (τ) before performing an A/D conversion.
Amplifier disabled and bypassed.
1
Gain = 1
1
Gain = 2
1
Gain = 5
2
Gain = 10
2
Gain = 20
2
Gain = 49
2
Gain = 98
Gain = open loop for trimming. Amplifier is
enabled.
This should give the amplifier time to settle within 0.5 LSB of
the A/D converter. This settling time needs to be taken into
effect if either the gain is changed or if the channel is
changed. Since these values are in different registers, they
can’t be changed simultaneously and must be changed individually. The settling time starts whenever either one is
changed, but it’s not cumulative. The user should wait the
amount of settling time specified after the latter of the channel or gain change.
TABLE 30. Programmable Gain Amplifier Settling Times
Time Constant (τ)
Settling Time (7.6 * τ)
1
Slew Rate Limited
Slew Rate Limited
2
Under-Damp Response
9µs
5
Under-Damp Response
6µs
10
0.7µs
5 µs
20
2 µs
16 µs
49
3.2 µs
25 µs
98
5.8 µs
45 µs
Open Loop
N/A
1050 µs
GAIN
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52
necessary to adjust both pairs. This is done with the use of
two volatile registers, AMPTRMN and AMPTRMP, and some
on-chip circuits. The two trim registers will allow for trimming
out the offset in 0.5 mV steps in either direction. Once the
amplifier is trimmed, the trim values are stored in AMPTRMN
and AMPTRMP. Retrimming is necessary after any type of
Reset. These two registers are initialized to 040 (hex) on a
Reset.
(Continued)
15.2.2 Programmable Gain Amplifier Offset Calibration
The programmable gain amplifier has an offset that could be
as high as ± 7 mV. When using this amplifier, a user may
want to nullify this offset to obtain more accurate measurements with the A/D converter. Since this amplifier has both
an N channel and P channel pair on its input stage, it’s
TABLE 31. AMPTRMN
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
CALN
ATRMN6
ATRMN5
ATRMN4
ATRMN3
ATRMN2
ATRMN1
ATRMN0
CALN
Enables the internal reference, VREFN, for
trimming the N channel pair. Enabled = 1, Disabled = 0. This bit, when = 1, also disables the
analog multiplexor. To perform the trimming algorithm, the TRIM bit must also = 1.
ATRMN6:0 Trim bits used for actual trimming. It uses a
signed magnitude method. ATRMN6 is the sign
bit. When ATRMN6 = 1, it compensates for
positive offset. When ATRMN6 = 0, it compensates for negative offset. ATRMN5:0 are the
magnitude of the trim with 000000 = no trim
value and 111111 = highest trim value.
TABLE 32. AMPTRMP
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
CALP
ATRMP6
ATRMP5
ATRMP4
ATRMP3
ATRMP2
ATRMP1
ATRMP0
CALP
Enables the internal reference, VREFP, for
trimming the P channel pair. Enabled = 1,
Disabled =0. This bit, when = 1, also disables
the analog multiplexor. To perform the trimming algorithm, the TRIM bit must also = 1.
ATRMNP6:0 Trim bits used for actual trimming. It uses a
signed magnitude method. ATRMP6 is the
sign bit. When ATRMP6 = 1, it compensates
for positive offset. When ATRMP6 = 0, it compensates for negative offset. ATRMP5:0 are
the magnitude of the trim with 000000 = no
trim value and 111111 = highest trim value.
The on-chip temperature sensor could also be used to measure temperature variations and determine whether retrimming of the offset is necessary.
15.2.3 Trimming the Offset on the Programmable Gain
Amplifier
Setting the TRIM bit puts the programmable gain amplifier
into a special configuration used for trimming the offset,
which is shown in Figure 28. This configuration enables the
amplifier and puts it into open loop gain. By selecting the
reference voltages, VREFN and VREFP, one at a time, the
offset can be calibrated using the A/D converter. The calibration routine uses software to perform a successive approximation algorithm and is indicated below. After the trim algorithm is complete, the trim values are stored in the
AMPTRMN and AMPTRMP registers and should remain,
unchanged, until the algorithm is executed again. The trim
values stored in AMPTRMN and AMPTRMP values are lost
if any type of reset is generated. Therefore, it’s necessary to
retrim after any type of Reset. A method to minimize retrimming would be to store the initial trim values into the virtual
EEPROM memory in addition to AMPTRMN and AMPTRMP.
Then, whenever necessary, the trim values could be retrieved from virtual EEPROM, avoiding execution of the trim
algorithm upon a Reset.
The amplifier offset can drift slightly as the temperature
changes. For example, over the entire temperature range of
−40˚C to +125˚C, the drift could be typically 2 mV. If the user
application is in a constantly changing temperature, and this
offset drift is a problem, it is recommended that the amplifier
be retrimmed periodically, or before critical measurements.
The procedure to trim both the N channel pair and P channel
pair are listed below. Steps 1–14 trim the N channel pair and
steps 15–30 trim the P channel pair.
20006358
FIGURE 28. Offset Trim Configuration when TRIM = 1
Note: AN-1199 contains sample assembly code which implements the
trim algorithm outline on step 1-30.
1.
2.
3.
4.
5.
6.
7.
8.
53
Set the TRIM bit = 1 in the ADGAIN register to configure
the amplifier.
Load C0h into the AMPTRMN register to select VREFN
and the no-trim value.
Wait 1.05 ms for the amplifier to settle.
Load 01h into ENAD to perform an A/D Conversion.
Store the result registers.
If the three most significant bits of the result are all ones,
go to step 8.
Else, if the three most significant bits are all zeros, go to
step 7.
Else, goto step 15.
Set ATRMN6 = 0
First time through loop, set ATRMN5 = 1
Second time through loop, set ATRMN4 = 1
Third time through loop, set ATRMN3 = 1
Fourth time through loop, set ATRMN2 = 1
Fifth time through loop, set ATRMN1 = 1
Sixth time through loop, set ATRMN0 = 1
Seventh time through loop, go to step 15.
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15.0 A/D Converter
Fifth time through loop, set ATRMP1 = 0
(Continued)
Sixth time through loop, set ATRMP0 = 0
9.
Wait 1.05 ms for the amplifier to settle.
28. Go to step 22.
29. Reset CALP bit = 0, but leave ATRMP6:0 unchanged.
10. Load 01h into ENAD to perform an A/D Conversion.
11. Store the result registers.
30. Reset the TRIM bit to 0.
12. If the three most significant bits of the result are all ones
and ATRMN6 = 1, go to step 8.
Else, if the three most significant bits are all zeros and
ATRMN6 = 1, go to step 13.
15.3 A/D OPERATION
The A/D conversion is completed within fifteen A/D converter
clocks. The A/D Converter interface works as follows. Setting
the ADBSY bit in the A/D control register ENAD initiates an
A/D conversion. The conversion sequence starts at the beginning of the write to ENAD operation which sets ADBSY,
thus powering up the A/D. At the first edge of the Converter
clock following the write operation, the sample signal turns
on for three clock cycles. At the end of the conversion, the
internal conversion complete signal will clear the ADBSY bit
and power down the A/D. The A/D 10-bit result is immediately loaded into the A/D result registers (ADRSTH and
ADRSTL) upon completion during TCSTART. This prevents
transient data (resulting from the A/D writing a new result
over an old one) being read from ADRSLT.
Inadvertent changes to the ENAD register during conversion
are prevented by the control logic of the A/D. Any attempt to
write any bit of the ENAD Register except ADBSY, while
ADBSY is a one, is ignored. ADBSY must be cleared either
by completion of an A/D conversion or by the user before the
prescaler, conversion mode or channel select values can be
changed. After stopping the current conversion, the user can
load different values for the prescaler, conversion mode or
channel select and start a new conversion in one instruction.
Else, if the three most significant bits are all ones and
ATRMN6 = 0, go to step 13.
Else, if the three most significant bits are all zeros and
ATRMN6 = 0, go to step 8.
Go to step 15.
13. First time through loop, set ATRMP5 = 0
Second time through loop, set ATRMP4 = 0
Third time through loop, set ATRMP3 = 0
Fourth time through loop, set ATRMP2 = 0
Fifth time through loop, set ATRMP1 = 0
Sixth time through loop, set ATRMP0 = 0
14. Go to step 8.
15. Reset CALN bit = 0, but leave ATRMN6 : 0 unchanged.
16. Load C0h into the AMPTRMP register to select VREFP
and the no-trim value.
17.
18.
19.
20.
Wait 1.05 ms for the amplifier to settle.
Load 01h into ENAD to perform an A/D Conversion.
Store the result registers.
If the three most significant bits of the result are all ones,
go to step 22.
Else, if the three most significant bits are all zeros, go to
step 21.
Else, goto step 29.
15.3.1 Prescaler
The A/D Converter (A/D) contains a prescaler option that
allows two different clock selections. The A/D clock frequency is equal to MCLK divided by the prescaler value.
Note that the prescaler value must be chosen such that the
A/D clock falls within the specified range. The maximum A/D
frequency is 1.67 MHz. This equates to a 600 ns A/D clock
cycle.
The A/D Converter takes 15 A/D clock cycles to complete a
conversion. Thus the minimum A/D conversion time is 12 µs
when a prescaler of 16 has been selected with MCLK = 20
MHz. The 15 A/D clock cycles needed for conversion consist
of 3 cycles for sampling, 1 cycle for auto-zeroing the comparator, 10 cycles for converting, 1 cycle for loading the
result into the result registers and for stopping and reinitializing. The ADBSY flag provides an A/D clock inhibit
function, which saves power by powering down the A/D
when it is not in use.
21. Set ATRMN6 = 0
22. First time through loop, set ATRMN5=1
Second time through loop, set ATRMN4=1
Third time through loop, set ATRMN3=1
Fourth time through loop, set ATRMN2=1
Fifth time through loop, set ATRMN1=1
Sixth time through loop, set ATRMN0=1
Seventh time through loop, go to step 29.
23.
24.
25.
26.
Wait 1.05 ms for the amplifier to settle.
Load 01h into ENAD to perform an A/D Conversion.
Store the result registers.
If the three most significant bits of the result are all ones
and ATRMN6 = 1, go to step 22.
Else, if the three most significant bits are all zeros and
ATRMN6 = 1, go to step 27.
Else, if the three most significant bits are all ones and
ATRMN6 = 0, go to step 27.
Else, if the three most significant bits are all zeros and
ATRMN6 = 0, go to step 22.
Go to step 29.
Note: The A/D Converter is also powered down when the device is in either
the HALT or IDLE modes. If the A/D is running when the device enters
the HALT or IDLE modes, the A/D powers down and then restarts the
conversion from the beginning with a corrupted sampled voltage (and
thus an invalid result) when the device comes out of the HALT or IDLE
modes.
Note: If a Breakpoint is issued during an A/D conversion, the conversion will
be completed.
15.4 ANALOG INPUT AND SOURCE RESISTANCE
CONSIDERATIONS
Figure 29 shows the A/D pin model in single ended mode.
The differential mode has a similar A/D pin model. The leads
to the analog inputs should be kept as short as possible.
Both noise and digital clock coupling to an A/D input can
cause conversion errors. The clock lead should be kept
away from the analog input line to reduce coupling.
27. First time through loop, set ATRMP5 = 0
Second time through loop, set ATRMP4 = 0
Third time through loop, set ATRMP3 = 0
Fourth time through loop, set ATRMP4 = 0
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If large source resistance is necessary, the recommended
solution is to slow down the A/D clock speed in proportion to
the source resistance. The A/D Converter may be operated
at the maximum speed for RS less than 3 kΩ. For RS greater
than 3 kΩ, A/D clock speed needs to be reduced. For example, with RS = 6 kΩ, the A/D Converter may be operated
at half the maximum speed. A/D Converter clock speed may
be slowed down by either increasing the A/D prescaler
divide-by or decreasing the CKI clock frequency. The A/D
minimum clock speed is 64 kHz.
(Continued)
Source impedances greater than 3 kΩ on the analog input
lines will adversely affect the internal RC charging time
during input sampling. As shown in Figure 29, the analog
switch to the Sample & Hold capacitor is closed only during
the 3 A/D cycle sample time. Large source impedances on
the analog inputs may result in the Sample & Hold capacitor
not being charged to the correct voltage levels, causing
scale errors.
20006362
*The analog switch is closed only during the sample time.
FIGURE 29. A/D Pin Model (Single Ended Mode)
extremely low. When using the HALT mode of the device, the
Temperature Sensor will draw current unless it is disabled by
software. Therefore, for minimal current in HALT mode, the
Temperature Sensor should be disabled prior to entering
HALT. A Reset will disable the Temperature Sensor.
16.0 Temperature Sensor
16.1 GENERAL DESCRIPTION
The Temperature Sensor on this device operates over a
−40˚C to +125˚C temperature range and produces an output
voltage proportional to the device temperature. The transfer
function is approximately linear. Refer to the A/D Converter
section to see how the Temperature Sensor is integrated
with the Programmable Gain Amplifier and A/D Converter.
The equation for VOUT vs. temperature is:
VOUT = [(−8.0 mV/˚C) X T] + 1.65V
16.2.1 Procedure for Reading the Temperature Sensor
Voltage
The following steps should be followed for measuring the
temperature sensor voltage:
1. Enable the Temperature Sensor by setting the ENTS bit
in the ADGAIN register to 1. The Programmable Gain
Amplifier gain should also be selected to be either 1 or 2.
2. Wait 350 µs for the temperature sensor to stabilize. This
is only required after ENTS bit is changed from 0 to 1.
3. Load the ENAD register with the channel number for the
temperature sensor, and the desired prescale value. The
ADMOD, MUX, and ADBSY bits should be 0.
4. Wait for the Programmable Gain Amplifier to stabilize
with the voltage for the newly selected channel.
5. Set the ADBSY bit in the ENAD register. The other bits in
the ENAD register should be the same as in step 3.
6. Wait for the ADBSY bit to go to 0 and then read the
output of the A/D Converter result registers, ADRSTH
and ADRSTL.
7. Subsequent readings of the temperature sensor can be
done by repeating steps 5 and 6, as long as the channel
number in ENAD has not changed from that of the
temperature sensor. If the channel number has been
changed to measure other channels, in between two
successive temperature sensor readings, then steps
1–6 should be followed.
where T is the temperature in ˚C.
The user can achieve greater temperature sensor accuracy
by performing a two temperature calibration to compensate
for device-to-device variations in slope and base value for
VOUT.
16.2 OPERATION
The Temperature Sensor is used in conjunction with the
on-chip Programmable Gain Amplifier and A/D converter to
read the Temperature Sensor output voltage. The Programmable Gain Amplifier must be used and the gain can be set
at either 1 or 2, depending on the operating voltage of the
device. To use a gain of 2, VCC should be greater than 4.5V.
The output voltage given in the above equation is for a gain
of 1. The Temperature Sensor is connected to channel 7 on
the A/D Converter multiplexor. See the A/D Converter section for more details on using the ENAD and ADGAIN registers.
The Temperature Sensor is enabled by setting the ENTS bits
in the ADGAIN register to a 1. The circuit will draw power
when it’s enabled. When disabled, the current drawn is
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COP8AME9
15.0 A/D Converter
COP8AME9
The electrical parameters of AMP1 are shown in the Electrical Characteristics section.
17.0 Stand-Alone Amplifier
A stand-alone Amplifier, AMP1, is provided on Port B. It
supports rail-to-rail inputs and outputs, and operates over
the entire VCC and temperature range. This amplifier is in
addition to the programmable gain amplifier in the A/D Converter. It is an alternate function on Port B.
17.1 BLOCK DIAGRAM
It is enabled/disabled by the ENAMP1 bit in the ADGAIN
register described in the A/D Converter section. The normal
port B3–B5 pins should be configured in their high Z state
when using AMP1. It is disabled after Reset. The circuit will
only draw current when it’s enabled. When disabled, the
current drawn is extremely low.
20006359
FIGURE 30. Amplifier1 Block Diagram
When using the HALT mode of the device, AMP1 will draw
current unless it is disabled by software. Therefore, for minimal current in HALT mode, AMP1 should be disabled prior to
entering HALT.
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56
The Software trap has the highest priority while the default
VIS has the lowest priority.
18.1 INTRODUCTION
Each of the 13 maskable inputs has a fixed arbitration ranking and vector.
Figure 31 shows the Interrupt block diagram.
The device supports fourteen vectored interrupts. Interrupt
sources include Timer 1, Timer 2, Timer 3, Timer T0, Port L
Wake-up, Software Trap, MICROWIRE/PLUS, USART and
External Input.
All interrupts force a branch to location 00FF Hex in program
memory. The VIS instruction may be used to vector to the
appropriate service routine from location 00FF Hex.
20006332
FIGURE 31. Interrupt Block Diagram
18.2 MASKABLE INTERRUPTS
All interrupts other than the Software Trap are maskable.
Each maskable interrupt has an associated enable bit and
pending flag bit. The pending bit is set to 1 when the interrupt
condition occurs. The state of the interrupt enable bit, combined with the GIE bit determines whether an active pending
flag actually triggers an interrupt. All of the maskable interrupt pending and enable bits are contained in mapped control registers, and thus can be controlled by the software.
A maskable interrupt condition triggers an interrupt under the
following conditions:
1. The enable bit associated with that interrupt is set.
2. The GIE bit is set.
3. The device is not processing a non-maskable interrupt.
(If a non-maskable interrupt is being serviced, a
maskable interrupt must wait until that service routine is
completed.)
An interrupt is triggered only when all of these conditions are
met at the beginning of an instruction. If different maskable
interrupts meet these conditions simultaneously, the highestpriority interrupt will be serviced first, and the other pending
interrupts must wait.
Upon Reset, all pending bits, individual enable bits, and the
GIE bit are reset to zero. Thus, a maskable interrupt condition cannot trigger an interrupt until the program enables it by
setting both the GIE bit and the individual enable bit. When
enabling an interrupt, the user should consider whether or
not a previously activated (set) pending bit should be acknowledged. If, at the time an interrupt is enabled, any
previous occurrences of the interrupt should be ignored, the
associated pending bit must be reset to zero prior to enabling the interrupt. Otherwise, the interrupt may be simply
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COP8AME9
18.0 Interrupts
COP8AME9
18.0 Interrupts
18.3 VIS INSTRUCTION
The general interrupt service routine, which starts at address
00FF Hex, must be capable of handling all types of interrupts. The VIS instruction, together with an interrupt vector
table, directs the device to the specific interrupt handling
routine based on the cause of the interrupt.
(Continued)
enabled; if the pending bit is already set, it will immediately
trigger an interrupt. A maskable interrupt is active if its associated enable and pending bits are set.
An interrupt is an asychronous event which may occur before, during, or after an instruction cycle. Any interrupt which
occurs during the execution of an instruction is not acknowledged until the start of the next normally executed instruction. If the next normally executed instruction is to be
skipped, the skip is performed before the pending interrupt is
acknowledged.
VIS is a single-byte instruction, typically used at the very
beginning of the general interrupt service routine at address
00FF Hex, or shortly after that point, just after the code used
for context switching. The VIS instruction determines which
enabled and pending interrupt has the highest priority, and
causes an indirect jump to the address corresponding to that
interrupt source. The jump addresses (vectors) for all possible interrupts sources are stored in a vector table.
At the start of interrupt acknowledgment, the following actions occur:
1.
The GIE bit is automatically reset to zero, preventing any
subsequent maskable interrupt from interrupting the current service routine. This feature prevents one maskable
interrupt from interrupting another one being serviced.
2. The address of the instruction about to be executed is
pushed onto the stack.
3. The program counter (PC) is loaded with 00FF Hex,
causing a jump to that program memory location.
The device requires seven instruction cycles to perform the
actions listed above.
If the user wishes to allow nested interrupts, the interrupts
service routine may set the GIE bit to 1 by writing to the PSW
register, and thus allow other maskable interrupts to interrupt
the current service routine. If nested interrupts are allowed,
caution must be exercised. The user must write the program
in such a way as to prevent stack overflow, loss of saved
context information, and other unwanted conditions.
The interrupt service routine stored at location 00FF Hex
should use the VIS instruction to determine the cause of the
interrupt, and jump to the interrupt handling routine corresponding to the highest priority enabled and active interrupt.
Alternately, the user may choose to poll all interrupt pending
and enable bits to determine the source(s) of the interrupt. If
more than one interrupt is active, the user’s program must
decide which interrupt to service.
The vector table may be as long as 32 bytes (maximum of 16
vectors) and resides at the top of the 256-byte block containing the VIS instruction. However, if the VIS instruction is
at the very top of a 256-byte block (such as at 00FF Hex),
the vector table resides at the top of the next 256-byte block.
Thus, if the VIS instruction is located somewhere between
00FF and 01DF Hex (the usual case), the vector table is
located between addresses 01E0 and 01FF Hex. If the VIS
instruction is located between 01FF and 02DF Hex, then the
vector table is located between addresses 02E0 and 02FF
Hex, and so on.
Each vector is 15 bits long and points to the beginning of a
specific interrupt service routine somewhere in the 32-kbyte
memory space. Each vector occupies two bytes of the vector
table, with the higher-order byte at the lower address. The
vectors are arranged in order of interrupt priority. The vector
of the maskable interrupt with the lowest rank is located to
0yE0 (higher-order byte) and 0yE1 (lower-order byte). The
next priority interrupt is located at 0yE2 and 0yE3, and so
forth in increasing rank. The Software Trap has the highest
rand and its vector is always located at 0yFE and 0yFF. The
number of interrupts which can become active defines the
size of the table.
Table 33 shows the types of interrupts, the interrupt arbitration ranking, and the locations of the corresponding vectors
in the vector table.
The vector table should be filled by the user with the memory
locations of the specific interrupt service routines. For example, if the Software Trap routine is located at 0310 Hex,
then the vector location 0yFE and -0yFF should contain the
data 03 and 10 Hex, respectively. When a Software Trap
interrupt occurs and the VIS instruction is executed, the
program jumps to the address specified in the vector table.
The interrupt sources in the vector table are listed in order of
rank, from highest to lowest priority. If two or more enabled
and pending interrupts are detected at the same time, the
one with the highest priority is serviced first. Upon return
from the interrupt service routine, the next highest-level
pending interrupt is serviced.
If the VIS instruction is executed, but no interrupts are enabled and pending, the lowest-priority interrupt vector is
used, and a jump is made to the corresponding address in
the vector table. This is an unusual occurrence and may be
the result of an error. It can legitimately result from a change
in the enable bits or pending flags prior to the execution of
the VIS instruction, such as executing a single cycle instruction which clears an enable flag at the same time that the
pending flag is set. It can also result, however, from inadvertent execution of the VIS command outside of the context
of an interrupt.
Within a specific interrupt service routine, the associated
pending bit should be cleared. This is typically done as early
as possible in the service routine in order to avoid missing
the next occurrence of the same type of interrupt event.
Thus, if the same event occurs a second time, even while the
first occurrence is still being serviced, the second occurrence will be serviced immediately upon return from the
current interrupt routine.
An interrupt service routine typically ends with an RETI
instruction. This instruction set the GIE bit back to 1, pops
the address stored on the stack, and restores that address to
the program counter. Program execution then proceeds with
the next instruction that would have been executed had
there been no interrupt. If there are any valid interrupts
pending, the highest-priority interrupt is serviced immediately upon return from the previous interrupt.
Note: While executing from the Boot ROM for ISP or virtual
E2 operations, the hardware will disable interrupts from occurring. The hardware will leave the GIE bit in its current
state, and if set, the hardware interrupts will occur when
execution is returned to Flash Memory. Subsequent interrupts, during ISP operation, from the same interrupt source
will be lost.
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To ensure reliable operation, the user should always use the
VIS instruction to determine the source of an interrupt. Although it is possible to poll the pending bits to detect the
source of an interrupt, this practice is not recommended. The
use of polling allows the standard arbitration ranking to be
altered, but the reliability of the interrupt system is compromised. The polling routine must individually test the enable
and pending bits of each maskable interrupt. If a Software
Trap interrupt should occur, it will be serviced last, even
though it should have the highest priority. Under certain
conditions, a Software Trap could be triggered but not serviced, resulting in an inadvertent “locking out” of all
maskable interrupts by the Software Trap pending flag.
Problems such as this can be avoided by using VIS
instruction.
(Continued)
The default VIS interrupt vector can be useful for applications in which time critical interrupts can occur during the
servicing of another interrupt. Rather than restoring the program context (A, B, X, etc.) and executing the RETI instruction, an interrupt service routine can be terminated by returning to the VIS instruction. In this case, interrupts will be
serviced in turn until no further interrupts are pending and
the default VIS routine is started. After testing the GIE bit to
ensure that execution is not erroneous, the routine should
restore the program context and execute the RETI to return
to the interrupted program.
This technique can save up to fifty instruction cycles (tC), or
more, (25 µs at 10 MHz oscillator) of latency for pending
interrupts with a penalty of fewer than ten instruction cycles
if no further interrupts are pending.
TABLE 33. Interrupt Vector Table
Arbitration Ranking
Vector Address (Note 16)
(Hi-Low Byte)
Source Description
(1) Highest
Software
(2)
Reserved for NMI
INTR Instruction
0yFE–0yFF
(3)
External
G0
0yFA–0yFB
(4)
Timer T0
Underflow
0yF8–0yF9
(5)
Timer T1
T1A/Underflow
0yF6–0yF7
(6)
Timer T1
T1B
0yF4–0yF5
(7)
MICROWIRE/PLUS
BUSY Low
0yF2–0yF3
(8)
Reserved
(9)
USART
(10)
USART
Transmit
0yEC–0yED
(11)
Timer T2
T2A/Underflow
0yEA–0yEB
(12)
Timer T2
T2B
0yE8–0yE9
(13)
Timer T3
T2A/Underflow
0yE6–0yE7
(14)
Timer T3
T3B
0yE4–0yE5
(15)
Port L/Wakeup
Port L Edge
0yE2–0yE3
(16) Lowest
Default VIS
Reserved
0yE0–0yE1
0yFC–0yFD
0yF0–0yF1
Receive
0yEE–0yEF
Note 16: y is a variable which represents the VIS block. VIS and the vector table must be located in the same 256-byte block except if VIS is located at the last
address of a block. In this case, the table must be in the next block.
18.3.1 VIS Execution
When the VIS instruction is executed it activates the arbitration logic. The arbitration logic generates an even number
between E0 and FE (E0, E2, E4, E6 etc....) depending on
which active interrupt has the highest arbitration ranking at
the time of the 1st cycle of VIS is executed. For example, if
the software trap interrupt is active, FE is generated. If the
external interrupt is active and the software trap interrupt is
not, then FA is generated and so forth. If no active interrupt
is pending, than E0 is generated. This number replaces the
lower byte of the PC. The upper byte of the PC remains
unchanged. The new PC is therefore pointing to the vector of
the active interrupt with the highest arbitration ranking. This
vector is read from program memory and placed into the PC
which is now pointed to the 1st instruction of the service
routine of the active interrupt with the highest arbitration
ranking.
Figure 32 illustrates the different steps performed by the VIS
instruction. Figure 33 shows a flowchart for the VIS instruction.
The non-maskable interrupt pending flag is cleared by the
RPND (Reset Non-Maskable Pending Bit) instruction (under
certain conditions) and upon RESET.
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18.0 Interrupts
COP8AME9
18.0 Interrupts
(Continued)
20006333
FIGURE 32. VIS Operation
18.4 NON-MASKABLE INTERRUPT
The Software Trap has the highest priority of all interrupts.
When a Software Trap occurs, the STPND bit is set. The GIE
bit is not affected and the pending bit (not accessible by the
user) is used to inhibit other interrupts and to direct the
program to the ST service routine with the VIS instruction.
Nothing can interrupt a Software Trap service routine except
for another Software Trap. The STPND can be reset only by
the RPND instruction or a chip Reset.
The Software Trap indicates an unusual or unknown error
condition. Generally, returning to normal execution at the
point where the Software Trap occurred cannot be done
reliably. Therefore, the Software Trap service routine should
re-initialize the stack pointer and perform a recovery procedure that re-starts the software at some known point, similar
to a device Reset, but not necessarily performing all the
same functions as a device Reset. The routine must also
execute the RPND instruction to reset the STPND flag.
Otherwise, all other interrupts will be locked out. To the
extent possible, the interrupt routine should record or indicate the context of the device so that the cause of the
Software Trap can be determined.
If the user wishes to return to normal execution from the
point at which the Software Trap was triggered, the user
must first execute RPND, followed by RETSK rather than
RETI or RET. This is because the return address stored on
the stack is the address of the INTR instruction that triggered
the interrupt. The program must skip that instruction in order
to proceed with the next one. Otherwise, an infinite loop of
Software Traps and returns will occur.
Programming a return to normal execution requires careful
consideration. If the Software Trap routine is interrupted by
another Software Trap, the RPND instruction in the service
routine for the second Software Trap will reset the STPND
flag; upon return to the first Software Trap routine, the
18.4.1 Pending Flag
There is a pending flag bit associated with the non-maskable
Software Trap interrupt, called STPND. This pending flag is
not memory-mapped and cannot be accessed directly by the
software.
The pending flag is reset to zero when a device Reset
occurs. When the non-maskable interrupt occurs, the associated pending bit is set to 1. The interrupt service routine
should contain an RPND instruction to reset the pending flag
to zero. The RPND instruction always resets the STPND
flag.
18.4.2 Software Trap
The Software Trap is a special kind of non-maskable interrupt which occurs when the INTR instruction (used to acknowledge interrupts) is fetched from program memory and
placed in the instruction register. This can happen in a
variety of ways, usually because of an error condition. Some
examples of causes are listed below.
If the program counter incorrectly points to a memory location beyond the programmed Flash memory space, the unused memory location returns zeros which is interpreted as
the INTR instruction.
If the stack is popped beyond the allowed limit (address 06F
Hex), a 7FFF will be loaded into the PC. Since the Option
Register resides at this location, and to maintain the integrity
of the stack overpop protection, the Flash memory will return
a zero on an instruction fetch and a software trap will be
triggered.
A Software Trap can be triggered by a temporary hardware
condition such as a brownout or power supply glitch.
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programming error or hardware condition (brownout, power
supply glitch, etc.) sets the STPND flag without providing a
way for it to be cleared, all other interrupts will be locked out.
To alleviate this condition, the user can use extra RPND
instructions in the main program and in the Watchdog service routine (if present). There is no harm in executing extra
RPND instructions in these parts of the program.
(Continued)
STPND flag will have the wrong state. This will allow
maskable interrupts to be acknowledged during the servicing
of the first Software Trap. To avoid problems such as this, the
user program should contain the Software Trap routine to
perform a recovery procedure rather than a return to normal
execution.
Under normal conditions, the STPND flag is reset by a
RPND instruction in the Software Trap service routine. If a
20006334
FIGURE 33. VIS Flow Chart
18.4.2.1 Programming Example: External Interrupt
WAIT:
PSW
CNTRL
RBIT
RBIT
SBIT
SBIT
SBIT
JP
.
.
.
.=0FF
VIS
.
.
.
.=01FA
.ADDRW SERVICE
=00EF
=00EE
0,PORTGC
0,PORTGD
IEDG, CNTRL
GIE, PSW
EXEN, PSW
WAIT
;
;
;
;
;
G0 pin configured Hi-Z
Ext interrupt polarity; falling edge
Set the GIE bit
Enable the external interrupt
Wait for external interrupt
;
;
;
;
The interrupt causes a
branch to address 0FF
The VIS causes a branch to
interrupt vector table
; Vector table (within 256 byte
; of VIS inst.) containing the ext
; interrupt service routine
.
.
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COP8AME9
18.0 Interrupts
COP8AME9
18.0 Interrupts
(Continued)
.
SERVICE:
RBIT,EXPND,PSW
.
.
.
RET I
; Interrupt Service Routine
; Reset ext interrupt pend. bit
; Return, set the GIE bit
18.5 PORT L INTERRUPTS
Port L provides the user with an additional eight fully selectable, edge sensitive interrupts which are all vectored into the
same service subroutine.
The interrupt from Port L shares logic with the wake-up
circuitry. The register WKEN allows interrupts from Port L to
be individually enabled or disabled. The register WKEDG
specifies the trigger condition to be either a positive or a
negative edge. Finally, the register WKPND latches in the
pending trigger conditions.
state, and if set, the hardware interrupts will occur when
execution is returned to Flash Memory. Subsequent interrupts, during ISP operation, from the same interrupt
source will be lost.
19.0 WATCHDOG/Clock Monitor
The devices contain a user selectable WATCHDOG and
clock monitor. The following section is applicable only if the
WATCHDOG feature has been selected in the Option register. The WATCHDOG is designed to detect the user program
getting stuck in infinite loops resulting in loss of program
control or “runaway” programs.
The GIE (Global Interrupt Enable) bit enables the interrupt
function.
A control flag, LPEN, functions as a global interrupt enable
for Port L interrupts. Setting the LPEN flag will enable interrupts and vice versa. A separate global pending flag is not
needed since the register WKPND is adequate.
Since Port L is also used for waking the device out of the
HALT or IDLE modes, the user can elect to exit the HALT or
IDLE modes either with or without the interrupt enabled. If he
elects to disable the interrupt, then the device will restart
execution from the instruction immediately following the instruction that placed the microcontroller in the HALT or IDLE
modes. In the other case, the device will first execute the
interrupt service routine and then revert to normal operation.
(See HALT MODE for clock option wake-up information.)
The WATCHDOG logic contains two separate service windows. While the user programmable upper window selects
the WATCHDOG service time, the lower window provides
protection against an infinite program loop that contains the
WATCHDOG service instruction. The WATCHDOG uses the
Idle Timer (T0) and thus all times are measured in Idle Timer
Clocks.
The Clock Monitor is used to detect the absence of a clock or
a very slow clock below a specified rate on tC.
The WATCHDOG consists of two independent logic blocks:
WD UPPER and WD LOWER. WD UPPER establishes the
upper limit on the service window and WD LOWER defines
the lower limit of the service window.
Servicing the WATCHDOG consists of writing a specific
value to a WATCHDOG Service Register named WDSVR
which is memory mapped in the RAM. This value is composed of three fields, consisting of a 2-bit Window Select, a
5-bit Key Data field, and the 1-bit Clock Monitor Select field.
Table 34 shows the WDSVR register.
18.6 INTERRUPT SUMMARY
The device uses the following types of interrupts, listed
below in order of priority:
1. The Software Trap non-maskable interrupt, triggered by
the INTR (00 opcode) instruction. The Software Trap is
acknowledged immediately. This interrupt service routine can be interrupted only by another Software Trap.
The Software Trap should end with two RPND instructions followed by a re-start procedure.
2. Maskable interrupts, triggered by an on-chip peripheral
block or an external device connected to the device.
Under ordinary conditions, a maskable interrupt will not
interrupt any other interrupt routine in progress. A
maskable interrupt routine in progress can be interrupted by the non-maskable interrupt request. A
maskable interrupt routine should end with an RETI
instruction or, prior to restoring context, should return to
execute the VIS instruction. This is particularly useful
when exiting long interrupt service routines if the time
between interrupts is short. In this case the RETI instruction would only be executed when the default VIS routine is reached.
3. While executing from the Boot ROM for ISP or virtual E2
operations, the hardware will disable interrupts from occurring. The hardware will leave the GIE bit in its current
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TABLE 34. WATCHDOG Service Register (WDSVR)
Window
Select
Clock
Monitor
Key Data
X
X
0
1
1
0
0
Y
7
6
5
4
3
2
1
0
The lower limit of the service window is fixed at 2048 Idle
Timer Clocks. Bits 7 and 6 of the WDSVR register allow the
user to pick an upper limit of the service window.
Table 35 shows the four possible combinations of lower and
upper limits for the WATCHDOG service window. This flexibility in choosing the WATCHDOG service window prevents
any undue burden on the user software.
Bits 5, 4, 3, 2 and 1 of the WDSVR register represent the
5-bit Key Data field. The key data is fixed at 01100. Bit 0 of
the WDSVR Register is the Clock Monitor Select bit.
62
(Continued)
TABLE 35. WATCHDOG Service Window Select
WDSVR
Bit 7
Clock
Monitor
Bit 0
WDSVR
Bit 6
Service Window
for High Speed Mode
(Lower-Upper Limits)
Service Window
for Dual Clock & Low Speed Modes
(Lower-Upper Limits)
0
0
X
2048-8k tC Cycles
2048-8k Cycles of 32 kHz Clk
0
1
X
2048-16k tC Cycles
2048-16k Cycles of 32 kHz Clk
1
0
X
2048-32k tC Cycles
2048-32k Cycles of 32 kHz Clk
1
1
X
2048-64k tC Cycles
2048-64k Cycles of 32 kHz Clk
X
X
0
Clock Monitor Disabled
Clock Monitor Disabled
X
X
1
Clock Monitor Enabled
Clock Monitor Enabled
19.1 CLOCK MONITOR
When jumping to the boot ROM for ISP and virtual E2
operations, the hardware will disable the lower window error
and perform an immediate WATCHDOG service. The ISP
routines will service the WATCHDOG within the selected
upper window. The ISP routines will service the WATCHDOG immediately prior to returning execution back to the
user’s code in flash. Therefore, after returning to flash
memory, the user can service the WATCHDOG anytime
following the return from boot ROM, but must service it within
the selected upper window to avoid a WATCHDOG error.
The WATCHDOG has an output pin associated with it. This
is the WDOUT pin, on pin 1 of the port G. WDOUT is active
low. The WDOUT pin has a weak pull-up in the inactive
state. Upon triggering the WATCHDOG, the logic will pull the
WDOUT (G1) pin low for an additional 16–32 cycles after the
signal level on WDOUT pin goes below the lower Schmitt
trigger threshold. After this delay, the device will stop forcing
the WDOUT output low. The WATCHDOG service window
will restart when the WDOUT pin goes high.
A WATCHDOG service while the WDOUT signal is active will
be ignored. The state of the WDOUT pin is not guaranteed
on reset, but if it powers up low then the WATCHDOG will
time out and WDOUT will go high.
The Clock Monitor forces the G1 pin low upon detecting a
clock frequency error. The Clock Monitor error will continue
until the clock frequency has reached the minimum specified
value, after which the G1 output will go high following 16–32
clock cycles. The Clock Monitor generates a continual Clock
Monitor error if the oscillator fails to start, or fails to reach the
minimum specified frequency. The specification for the Clock
Monitor is as follows:
1/tC > 5 kHz — No clock rejection.
1/tC < 10 Hz — Guaranteed clock rejection.
The Clock Monitor aboard the device can be selected or
deselected under program control. The Clock Monitor is
guaranteed not to reject the clock if the instruction cycle
clock (1/tC) is greater or equal to 5 kHz. This equates to a
clock input rate on the selected oscillator of greater or equal
to 25 kHz.
19.2 WATCHDOG/CLOCK MONITOR OPERATION
The WATCHDOG is enabled by bit 2 of the Option register.
When this Option bit is 0, the WATCHDOG is enabled and
pin G1 becomes the WATCHDOG output with a weak pullup.
The WATCHDOG and Clock Monitor are disabled during
reset. The device comes out of reset with the WATCHDOG
armed, the WATCHDOG Window Select bits (bits 6, 7 of the
WDSVR Register) set, and the Clock Monitor bit (bit 0 of the
WDSVR Register) enabled. Thus, a Clock Monitor error will
occur after coming out of reset, if the instruction cycle clock
frequency has not reached a minimum specified value, including the case where the oscillator fails to start.
The WDSVR register can be written to only once after reset
and the key data (bits 5 through 1 of the WDSVR Register)
must match to be a valid write. This write to the WDSVR
register involves two irrevocable choices: (i) the selection of
the WATCHDOG service window (ii) enabling or disabling of
the Clock Monitor. Hence, the first write to WDSVR Register
involves selecting or deselecting the Clock Monitor, select
the WATCHDOG service window and match the WATCHDOG key data. Subsequent writes to the WDSVR register
will compare the value being written by the user to the
WATCHDOG service window value, the key data and the
Clock Monitor Enable (all bits) in the WDSVR Register. Table
36 shows the sequence of events that can occur.
The user must service the WATCHDOG at least once before
the upper limit of the service window expires. The
WATCHDOG may not be serviced more than once in every
lower limit of the service window.
TABLE 36. WATCHDOG Service Actions
Key Data
Window Data
Clock Monitor
Action
Match
Match
Match
Don’t Care
Mismatch
Don’t Care
Valid Service: Restart Service Window
Error: Generate WATCHDOG Output
Mismatch
Don’t Care
Don’t Care
Error: Generate WATCHDOG Output
Don’t Care
Don’t Care
Mismatch
Error: Generate WATCHDOG Output
• Both the WATCHDOG and CLOCK MONITOR detector
circuits are inhibited during RESET.
19.3 WATCHDOG AND CLOCK MONITOR SUMMARY
The following salient points regarding the WATCHDOG and
CLOCK MONITOR should be noted:
63
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COP8AME9
19.0 WATCHDOG/Clock Monitor
COP8AME9
19.0 WATCHDOG/Clock Monitor
19.4 DETECTION OF ILLEGAL CONDITIONS
The device can detect various illegal conditions resulting
from coding errors, transient noise, power supply voltage
drops, runaway programs, etc.
(Continued)
• Following RESET, the WATCHDOG and CLOCK MONITOR are both enabled, with the WATCHDOG having the
maximum service window selected.
• The WATCHDOG service window and CLOCK MONITOR enable/disable option can only be changed once,
during the initial WATCHDOG service following RESET.
• The initial WATCHDOG service must match the key data
value in the WATCHDOG Service register WDSVR in
order to avoid a WATCHDOG error.
• Subsequent WATCHDOG services must match all three
data fields in WDSVR in order to avoid WATCHDOG
errors.
• The correct key data value cannot be read from the
WATCHDOG Service register WDSVR. Any attempt to
read this key data value of 01100 from WDSVR will read
as key data value of all 0’s.
• The WATCHDOG detector circuit is inhibited during both
the HALT and IDLE modes.
• The CLOCK MONITOR detector circuit is active during
both the HALT and IDLE modes. Consequently, the device inadvertently entering the HALT mode will be detected as a CLOCK MONITOR error (provided that the
CLOCK MONITOR enable option has been selected by
the program). Likewise, a device with WATCHDOG enabled in the Option but with the WATCHDOG output not
connected to RESET, will draw excessive HALT current if
placed in the HALT mode. The clock Monitor will pull the
WATCHDOG output low and sink current through the
on-chip pull-up resistor.
• The WATCHDOG service window will be set to its selected value from WDSVR following HALT. Consequently,
the WATCHDOG should not be serviced for at least 2048
Idle Timer clocks following HALT, but must be serviced
within the selected window to avoid a WATCHDOG error.
• The IDLE timer T0 is not initialized with external RESET.
• The user can sync in to the IDLE counter cycle with an
IDLE counter (T0) interrupt or by monitoring the T0PND
flag. The T0PND flag is set whenever the selected bit of
the IDLE counter toggles (every 4, 8, 16, 32 or 64k Idle
Timer clocks). The user is responsible for resetting the
T0PND flag.
• A hardware WATCHDOG service occurs just as the device exits the IDLE mode. Consequently, the
WATCHDOG should not be serviced for at least 2048 Idle
Timer clocks following IDLE, but must be serviced within
the selected window to avoid a WATCHDOG error.
• Following RESET, the initial WATCHDOG service (where
the service window and the CLOCK MONITOR enable/
disable must be selected) may be programmed anywhere within the maximum service window (65,536 instruction cycles) initialized by RESET. Note that this initial
WATCHDOG service may be programmed within the initial 2048 instruction cycles without causing a
WATCHDOG error.
• When using any of the ISP functions in Boot ROM, the
ISP routines will service the WATCHDOG within the selected upper window. Upon return to flash memory, the
WATCHDOG is serviced, the lower window is enabled,
and the user can service the WATCHDOG anytime following exit from Boot ROM, but must service it within the
selected upper window to avoid a WATCHDOG error.
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Reading of unprogrammed ROM gets zeros. The opcode for
software interrupt is 00. If the program fetches instructions
from unprogrammed ROM, this will force a software interrupt, thus signaling that an illegal condition has occurred.
The subroutine stack grows down for each call (jump to
subroutine), interrupt, or PUSH, and grows up for each
return or POP. The stack pointer is initialized to RAM location
06F Hex during reset. Consequently, if there are more returns than calls, the stack pointer will point to addresses 070
and 071 Hex (which are undefined RAM). Undefined RAM
from addresses 070 to 07F (Segment 0), and all other segments (i.e., Segments 4... etc.) is read as all 1’s, which in
turn will cause the program to return to address 7FFF Hex.
The Option Register is located at this location and, when
accessed by an instruction fetch, will respond with an INTR
instruction (all 0’s) to generate a software interrupt, signalling
an illegal condition on overpop of the stack.
Thus, the chip can detect the following illegal conditions:
1.
2.
Executing from undefined Program Memory
Over “POP”ing the stack by having more returns than
calls.
When the software interrupt occurs, the user can re-initialize
the stack pointer and do a recovery procedure before restarting (this recovery program is probably similar to that following reset, but might not contain the same program initialization procedures). The recovery program should reset the
software interrupt pending bit using the RPND instruction.
20.0 MICROWIRE/PLUS
MICROWIRE/PLUS is a serial SPI compatible synchronous
communications interface. The MICROWIRE/PLUS capability enables the device to interface with MICROWIRE/PLUS
or SPI peripherals (i.e. A/D converters, display drivers,
EEPROMs etc.) and with other microcontrollers which support the MICROWIRE/PLUS or SPI interface. It consists of
an 8-bit serial shift register (SIO) with serial data input (SI),
serial data output (SO) and serial shift clock (SK). Figure 34
shows a block diagram of the MICROWIRE/PLUS logic.
The shift clock can be selected from either an internal source
or an external source. Operating the MICROWIRE/PLUS
arrangement with the internal clock source is called the
Master mode of operation. Similarly, operating the
MICROWIRE/PLUS arrangement with an external shift clock
is called the Slave mode of operation.
The CNTRL register is used to configure and control the
MICROWIRE/PLUS mode. To use the MICROWIRE/PLUS,
the MSEL bit in the CNTRL register is set to one. In the
master mode, the SK clock rate is selected by the two bits,
SL0 and SL1, in the CNTRL register. Table 37 details the
different clock rates that may be selected.
TABLE 37. MICROWIRE/PLUS
Master Mode Clock Select
SL1
SL0
SK Period
0
0
2 x tC
0
1
4 x tC
1
x
8 x tC
Where tC is the instruction cycle clock
64
20.1.2 MICROWIRE/PLUS Slave Mode Operation
(Continued)
In the MICROWIRE/PLUS Slave mode of operation the SK
clock is generated by an external source. Setting the MSEL
bit in the CNTRL register enables the SO and SK functions
onto the G Port. The SK pin must be selected as an input
and the SO pin is selected as an output pin by setting and
resetting the appropriate bits in the Port G configuration
register. Table 38 summarizes the settings required to enter
the Slave mode of operation.
20.1 MICROWIRE/PLUS OPERATION
Setting the BUSY bit in the PSW register causes the
MICROWIRE/PLUS to start shifting the data. It gets reset
when eight data bits have been shifted. The user may reset
the BUSY bit by software to allow less than 8 bits to shift. If
enabled, an interrupt is generated when eight data bits have
been shifted. The device may enter the MICROWIRE/PLUS
mode either as a Master or as a Slave. Figure 34 shows how
two microcontroller devices and several peripherals may be
interconnected using the MICROWIRE/PLUS arrangements.
TABLE 38. MICROWIRE/PLUS Mode Settings
This table assumes that the control flag MSEL is set.
Warning:
The SIO register should only be loaded when the SK clock is
in the idle phase. Loading the SIO register while the SK clock
is in the active phase, will result in undefined data in the SIO
register.
Setting the BUSY flag when the input SK clock is in the
active phase while in the MICROWIRE/PLUS is in the slave
mode may cause the current SK clock for the SIO shift
register to be narrow. For safety, the BUSY flag should only
be set when the input SK clock is in the idle phase.
G4 (SO)
G5 (SK)
G4
G5
Config. Bit
Config. Bit
Fun.
Fun.
1
1
SO
Int.
MICROWIRE/PLUS
SK
Master
0
1
0
20.1.1 MICROWIRE/PLUS Master Mode Operation
In the MICROWIRE/PLUS Master mode of operation the
shift clock (SK) is generated internally. The MICROWIRE/
PLUS Master always initiates all data exchanges. The MSEL
bit in the CNTRL register must be set to enable the SO and
SK functions onto the G Port. The SO and SK pins must also
be selected as outputs by setting appropriate bits in the Port
G configuration register. In the slave mode, the shift clock
stops after 8 clock pulses. Table 38 summarizes the bit
settings required for Master mode of operation.
1
0
0
Operation
TRI-
Int.
MICROWIRE/PLUS
STATE
SK
Master
SO
Ext.
MICROWIRE/PLUS
SK
Slave
TRI-
Ext.
MICROWIRE/PLUS
STATE
SK
Slave
The user must set the BUSY flag immediately upon entering
the Slave mode. This ensures that all data bits sent by the
Master is shifted properly. After eight clock pulses the BUSY
flag is clear, the shift clock is stopped, and the sequence
may be repeated.
20006335
FIGURE 34. MICROWIRE/PLUS Application
20.1.2.1 Alternate SK Phase Operation and SK Idle
Polarity
clock. The SIO register is shifted on each falling edge of the
SK clock. In the alternate SK phase operation, data is shifted
in on the falling edge of the SK clock and shifted out on the
rising edge of the SK clock. Bit 6 of Port G configuration
register selects the SK edge.
A control flag, SKSEL, allows either the normal SK clock or
the alternate SK clock to be selected. Refer to Table 39 for
the appropriate setting of the SKSEL bit. The SKSEL is
The device allows either the normal SK clock or an alternate
phase SK clock to shift data in and out of the SIO register. In
both the modes the SK idle polarity can be either high or low.
The polarity is selected by bit 5 of Port G data register. In the
normal mode data is shifted in on the rising edge of the SK
clock and the data is shifted out on the falling edge of the SK
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COP8AME9
20.0 MICROWIRE/PLUS
COP8AME9
20.0 MICROWIRE/PLUS
power up in the reset condition, selecting the normal SK
signal provided the SK Idle Polarity remains LOW.
(Continued)
mapped into the G6 configuration bit. The SKSEL flag will
TABLE 39. MICROWIRE/PLUS Shift Clock Polarity and Sample/Shift Phase
Port G
SK Phase
G6 (SKSEL)
Config. Bit
G5 Data
Bit
SO Clocked Out On:
SI Sampled On:
SK Idle Phase
Normal
0
0
SK Falling Edge
SK Rising Edge
Low
Alternate
1
0
SK Rising Edge
SK Falling Edge
Low
Alternate
0
1
SK Rising Edge
SK Falling Edge
High
Normal
1
1
SK Falling Edge
SK Rising Edge
High
20006336
FIGURE 35. MICROWIRE/PLUS SPI Mode Interface Timing, Normal SK Mode, SK Idle Phase being Low
20006337
FIGURE 36. MICROWIRE/PLUS SPI Mode Interface Timing, Alternate SK Mode, SK Idle Phase being Low
20006338
FIGURE 37. MICROWIRE/PLUS SPI Mode Interface Timing, Normal SK Mode, SK Idle Phase being High
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66
COP8AME9
20.0 MICROWIRE/PLUS
(Continued)
20006339
FIGURE 38. MICROWIRE/PLUS SPI Mode Interface Timing, Alternate SK Mode, SK Idle Phase being High
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COP8AME9
21.0 Memory Map
Address
Address
Contents
S/ADD REG
All RAM, ports and registers (except A and PC) are mapped
into data memory address space.
Contents
xxBD
USART Baud Register (BAUD)
xxBE
USART Prescale Select Register (PSR)
xxBF
Reserved
0000 to 006F
On-Chip RAM bytes (112 bytes)
xxC0
Timer T2 Lower Byte
0070 to 007F
Unused RAM Address Space (Reads As
All Ones)
xxC1
Timer T2 Upper Byte
xxC2
xx80 to xx90
Unused RAM Address Space (Reads As
Undefined Data)
Timer T2 Autoload Register T2RA Lower
Byte
xxC3
xx90 to xx9B
Reserved
Timer T2 Autoload Register T2RA Upper
Byte
xx9C
Programmable Gain Amplifier Offset
Trim Register for N Channel Pair
(AMPTRMN)
xxC4
Timer T2 Autoload Register T2RB Lower
Byte
xxC5
Timer T2 Autoload Register T2RB Upper
Byte
xxC6
Timer T2 Control Register
xxC7
WATCHDOG Service Register
(Reg:WDSVR)
xxC8
MIWU Edge Select Register
(Reg:WKEDG)
S/ADD REG
xx9D
Programmable Gain Amplifier Offset
Trim Register for P Channel Pair
(AMPTRMP)
xx9E
Reserved
xx9F
Reserved
xxA0 to xxA3
Reserved
xxA4
Port B Data Register
xxC9
MIWU Enable Register (Reg:WKEN)
xxA5
Port B Configuration Register
xxCA
MIWU Pending Register (Reg:WKPND)
xxA6
Port B Input Pins (Read Only)
xxCB
A/D Converter Control Register (ENAD)
xxA7
Reserved for Port B
xxCC
xxA8
ISP Address Register Low Byte
(ISPADLO)
A/D Converter Result Register High Byte
(ADRSTH)
xxCD
xxA9
ISP Address Register High Byte
(ISPADHI)
A/D Converter Result Register Low Byte
(ADRSTL)
xxCE
A/D Amplifier Gain Register (ADGAIN)
xxAA
ISP Read Data Register (ISPRD)
xxCF
Idle Timer Control Register (ITMR)
xxAB
ISP Write Data Register (ISPWR)
xxD0
Port L Data Register
xxAC to xxAE
Reserved
xxD1
Port L Configuration Register
xxAF
High Speed Timers Control Register
(HSTCR)
xxD2
Port L Input Pins (Read Only)
xxD3
Reserved
xxB0
Timer T3 Lower Byte
xxD4
Port G Data Register
xxB1
Timer T3 Upper Byte
xxD5
Port G Configuration Register
xxB2
Timer T3 Autoload Register T3RA Lower
Byte
xxD6
Port G Input Pins (Read Only)
xxD7 to xxDF
Reserved
xxB3
Timer T3 Autoload Register T3RA Upper
Byte
xxE0
Reserved
xxE1
xxB4
Timer T3 Autoload Register T3RB Lower
Byte
E2 and Flash Memory Write Timing
Register (PGMTIM)
xxE2
ISP Key Register (ISPKEY)
xxB5
Timer T3 Autoload Register T3RB Upper
Byte
xxE3 to xxE5
Reserved
xxE6
Timer T1 Autoload Register T1RB Lower
Byte
xxE7
Timer T1 Autoload Register T1RB Upper
Byte
ICNTRL Register
xxB6
Timer T3 Control Register
xxB7
Reserved
xxB8
USART Transmit Buffer (TBUF)
xxB9
USART Receive Buffer (RBUF)
xxE8
xxBA
USART Control and Status Register
(ENU)
xxE9
MICROWIRE/PLUS Shift Register
xxEA
Timer T1 Lower Byte
USART Receive Control and Status
Register (ENUR)
xxEB
Timer T1 Upper Byte
xxEC
Timer T1 Autoload Register T1RA Lower
Byte
xxBB
xxBC
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USART Interrupt and Clock Source
Register (ENUI)
68
ing) data. Transfer-of-control addressing modes are used in
conjunction with jump instructions to control the execution
sequence of the software program.
(Continued)
Address
Contents
S/ADD REG
xxED
Timer T1 Autoload Register T1RA Upper
Byte
xxEE
CNTRL Control Register
xxEF
PSW Register
xxF0 to FB
On-Chip RAM Mapped as Registers
xxFC
X Register
xxFD
SP Register
xxFE
B Register
xxFF
S Register
0100 to 017F
On-Chip 128 RAM Bytes
0200 to 027F
On-Chip 128 RAM Bytes
0300 to 037F
On-Chip 128 RAM Bytes
22.3.1 Operand Addressing Modes
The operand of an instruction specifies what memory location is to be affected by that instruction. Several different
operand addressing modes are available, allowing memory
locations to be specified in a variety of ways. An instruction
can specify an address directly by supplying the specific
address, or indirectly by specifying a register pointer. The
contents of the register (or in some cases, two registers)
point to the desired memory location. In the immediate
mode, the data byte to be used is contained in the instruction
itself.
Each addressing mode has its own advantages and disadvantages with respect to flexibility, execution speed, and
program compactness. Not all modes are available with all
instructions. The Load (LD) instruction offers the largest
number of addressing modes.
The available addressing modes are:
• Direct
Note: Reading memory locations 0070H–007FH (Segment 0) will return all
ones. Reading unused memory locations 0080H–0093H (Segment 0)
will return undefined data. Reading memory locations from other Segments (i.e., Segment 4, Segment 5, … etc.) will return undefined data.
• Register B or X Indirect
• Register B or X Indirect with Post-Incrementing/
Decrementing
• Immediate
• Immediate Short
• Indirect from Program Memory
The addressing modes are described below. Each description includes an example of an assembly language instruction using the described addressing mode.
Direct. The memory address is specified directly as a byte in
the instruction. In assembly language, the direct address is
written as a numerical value (or a label that has been defined
elsewhere in the program as a numerical value).
Example: Load Accumulator Memory Direct
LD A,05
22.0 Instruction Set
22.1 INTRODUCTION
This section defines the instruction set of the COP8 Family
members. It contains information about the instruction set
features, addressing modes and types.
22.2 INSTRUCTION FEATURES
The strength of the instruction set is based on the following
features:
• Mostly single-byte opcode instructions minimize program
size.
• One instruction cycle for the majority of single-byte instructions to minimize program execution time.
• Many single-byte, multiple function instructions such as
DRSZ.
• Three memory mapped pointers: two for register indirect
addressing, and one for the software stack.
• Sixteen memory mapped registers that allow an optimized implementation of certain instructions.
• Ability to set, reset, and test any individual bit in data
memory address space, including the memory-mapped
I/O ports and registers.
• Register-Indirect LOAD and EXCHANGE instructions
with optional automatic post-incrementing or decrementing of the register pointer. This allows for greater efficiency (both in cycle time and program code) in loading,
walking across and processing fields in data memory.
• Unique instructions to optimize program size and
throughput efficiency. Some of these instructions are:
DRSZ, IFBNE, DCOR, RETSK, VIS and RRC.
Reg/Data
Contents
Memory
Before
After
Accumulator
XX Hex
A6 Hex
A6 Hex
A6 Hex
Memory Location
0005 Hex
Contents
Register B or X Indirect. The memory address is specified
by the contents of the B Register or X register (pointer
register). In assembly language, the notation [B] or [X] specifies which register serves as the pointer.
Example: Exchange Memory with Accumulator, B Indirect
X A,[B]
Reg/Data
Contents
Memory
Before
After
Accumulator
01 Hex
87 Hex
87 Hex
01 Hex
05 Hex
05 Hex
Memory Location
0005 Hex
22.3 ADDRESSING MODES
The instruction set offers a variety of methods for specifying
memory addresses. Each method is called an addressing
mode. These modes are classified into two categories: operand addressing modes and transfer-of-control addressing
modes. Operand addressing modes are the various methods of specifying an address for accessing (reading or writ-
Contents
B Pointer
Register B or X Indirect with Post-Incrementing/
Decrementing. The relevant memory address is specified
by the contents of the B Register or X register (pointer
register). The pointer register is automatically incremented
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COP8AME9
21.0 Memory Map
COP8AME9
22.0 Instruction Set
22.3.2 Tranfer-of-Control Addressing Modes
Program instructions are usually executed in sequential order. However, Jump instructions can be used to change the
normal execution sequence. Several transfer-of-control addressing modes are available to specify jump addresses.
A change in program flow requires a non-incremental
change in the Program Counter contents. The Program
Counter consists of two bytes, designated the upper byte
(PCU) and lower byte (PCL). The most significant bit of PCU
is not used, leaving 15 bits to address the program memory.
(Continued)
or decremented after execution, allowing easy manipulation
of memory blocks with software loops. In assembly language, the notation [B+], [B−], [X+], or [X−] specifies which
register serves as the pointer, and whether the pointer is to
be incremented or decremented.
Example: Exchange Memory with Accumulator, B Indirect
with Post-Increment
X A,[B+]
Reg/Data
Contents
Memory
Before
After
Accumulator
03 Hex
62 Hex
62 Hex
03 Hex
05 Hex
06 Hex
Memory Location
0005 Hex
B Pointer
Different addressing modes are used to specify the new
address for the Program Counter. The choice of addressing
mode depends primarily on the distance of the jump. Farther
jumps sometimes require more instruction bytes in order to
completely specify the new Program Counter contents.
The available transfer-of-control addressing modes are:
Contents
• Jump Relative
• Jump Absolute
• Jump Absolute Long
• Jump Indirect
The transfer-of-control addressing modes are described below. Each description includes an example of a Jump instruction using a particular addressing mode, and the effect
on the Program Counter bytes of executing that instruction.
Jump Relative. In this 1-byte instruction, six bits of the
instruction opcode specify the distance of the jump from the
current program memory location. The distance of the jump
can range from −31 to +32. A JP+1 instruction is not allowed.
The programmer should use a NOP instead.
Example: Jump Relative
JP 0A
Intermediate. The data for the operation follows the instruction opcode in program memory. In assembly language, the
number sign character (#) indicates an immediate operand.
Example: Load Accumulator Immediate
LD A,#05
Reg/Data
Contents
Contents
Memory
Before
After
Accumulator
XX Hex
05 Hex
Immediate Short. This is a special case of an immediate
instruction. In the “Load B immediate” instruction, the 4-bit
immediate value in the instruction is loaded into the lower
nibble of the B register. The upper nibble of the B register is
reset to 0000 binary.
Example: Load B Register Immediate Short
LD B,#7
Reg/Data
Contents
Reg
Contents
Memory
Before
After
B Pointer
12 Hex
07 Hex
Contents
Before
After
PCU
04 Hex
04 Hex
PCL
35 Hex
36 Hex
Accumulator
1F Hex
25 Hex
Memory Location
041F Hex
www.national.com
25 Hex
After
PCU
02 Hex
02 Hex
PCL
05 Hex
0F Hex
Contents
Contents
Before
After
PCU
0C Hex
01 Hex
PCL
77 Hex
25 Hex
Reg
Jump Absolute Long. In this 3-byte instruction, 15 bits of
the instruction opcode specify the new contents of the Program Counter.
Example: Jump Absolute Long
JMP 03625
Contents
Memory
Contents
Before
Jump Absolute. In this 2-byte instruction, 12 bits of the
instruction opcode specify the new contents of the Program
Counter. The upper three bits of the Program Counter remain unchanged, restricting the new Program Counter address to the same 4k-byte address space as the current
instruction. (This restriction is relevant only in devices using
more than one 4k-byte program memory space.)
Example: Jump Absolute
JMP 0125
Indirect from Program Memory. This is a special case of
an indirect instruction that allows access to data tables
stored in program memory. In the “Load Accumulator Indirect” (LAID) instruction, the upper and lower bytes of the
Program Counter (PCU and PCL) are used temporarily as a
pointer to program memory. For purposes of accessing program memory, the contents of the Accumulator and PCL are
exchanged. The data pointed to by the Program Counter is
loaded into the Accumulator, and simultaneously, the original
contents of PCL are restored so that the program can resume normal execution.
Example: Load Accumulator Indirect
LAID
Reg/Data
Contents
25 Hex
70
Reg/
Contents
Memory
Before
Contents
After
PCU
42 Hex
36 Hex
PCL
36 Hex
25 Hex
Jump to Subroutine Long (JSRL)
(Continued)
Jump to Boot ROM Subroutine (JSRB)
Return from Subroutine (RET)
Jump Indirect. In this 1-byte instruction, the lower byte of
the jump address is obtained from a table stored in program
memory, with the Accumulator serving as the low order byte
of a pointer into program memory. For purposes of accessing program memory, the contents of the Accumulator are
written to PCL (temporarily). The data pointed to by the
Program Counter (PCH/PCL) is loaded into PCL, while PCH
remains unchanged.
Example: Jump Indirect
Return from Subroutine and Skip (RETSK)
Return from Interrupt (RETI)
Software Trap Interrupt (INTR)
Vector Interrupt Select (VIS)
22.4.3 Load and Exchange Instructions
The load and exchange instructions write byte values in
registers or memory. The addressing mode determines the
source of the data.
Load (LD)
JID
Reg/
Contents
Memory
Before
After
PCU
01 Hex
01 Hex
PCL
C4 Hex
32 Hex
Accumulator
26 Hex
26 Hex
Contents
32 Hex
32 Hex
Load Accumulator Indirect (LAID)
Exchange (X)
22.4.4 Logical Instructions
The logical instructions perform the operations AND, OR,
and XOR (Exclusive OR). Other logical operations can be
performed by combining these basic operations. For example, complementing is accomplished by exclusive-ORing
the Accumulator with FF Hex.
Logical AND (AND)
Logical OR (OR)
Exclusive OR (XOR)
Memory
Location
COP8AME9
22.0 Instruction Set
0126 Hex
The VIS instruction is a special case of the Indirect Transfer
of Control addressing mode, where the double-byte vector
associated with the interrupt is transferred from adjacent
addresses in program memory into the Program Counter in
order to jump to the associated interrupt service routine.
22.4.5 Accumulator Bit Manipulation Instructions
The Accumulator bit manipulation instructions allow the user
to shift the Accumulator bits and to swap its two nibbles.
Rotate Right Through Carry (RRC)
Rotate Left Through Carry (RLC)
Swap Nibbles of Accumulator (SWAP)
22.4 INSTRUCTION TYPES
The instruction set contains a wide variety of instructions.
The available instructions are listed below, organized into
related groups.
Some instructions test a condition and skip the next instruction if the condition is not true. Skipped instructions are
executed as no-operation (NOP) instructions.
22.4.6 Stack Control Instructions
Push Data onto Stack (PUSH)
Pop Data off of Stack (POP)
22.4.1 Arithmetic Instructions
The arithmetic instructions perform binary arithmetic such as
addition and subtraction, with or without the Carry bit.
Add (ADD)
Add with Carry (ADC)
Subtract with Carry (SUBC)
Increment (INC)
Decrement (DEC)
Decimal Correct (DCOR)
Clear Accumulator (CLR)
Set Carry (SC)
Reset Carry (RC)
22.4.7 Memory Bit Manipulation Instructions
The memory bit manipulation instructions allow the user to
set and reset individual bits in memory.
Set Bit (SBIT)
Reset Bit (RBIT)
Reset Pending Bit (RPND)
22.4.8 Conditional Instructions
The conditional instruction test a condition. If the condition is
true, the next instruction is executed in the normal manner; if
the condition is false, the next instruction is skipped.
If Equal (IFEQ)
If Not Equal (IFNE)
If Greater Than (IFGT)
If Carry (IFC)
If Not Carry (IFNC)
If Bit (IFBIT)
If B Pointer Not Equal (IFBNE)
And Skip if Zero (ANDSZ)
Decrement Register and Skip if Zero (DRSZ)
22.4.2 Transfer-of-Control Instructions
The transfer-of-control instructions change the usual sequential program flow by altering the contents of the Program Counter. The Jump to Subroutine instructions save the
Program Counter contents on the stack before jumping; the
Return instructions pop the top of the stack back into the
Program Counter.
Jump Relative (JP)
Jump Absolute (JMP)
Jump Absolute Long (JMPL)
Jump Indirect (JID)
Jump to Subroutine (JSR)
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COP8AME9
22.0 Instruction Set
(Continued)
Registers
22.4.9 No-Operation Instruction
PL
Lower 8 Bits of PC
The no-operation instruction does nothing, except to occupy
space in the program memory and time in execution.
No-Operation (NOP)
C
1 Bit of PSW Register for Carry
HC
1 Bit of PSW Register for Half Carry
GIE
1 Bit of PSW Register for Global Interrupt
Enable
VU
Interrupt Vector Upper Byte
VL
Interrupt Vector Lower Byte
Note: The VIS is a special case of the Indirect Transfer of
Control addressing mode, where the double byte vector
associated with the interrupt is transferred from adjacent
addresses in the program memory into the program counter
(PC) in order to jump to the associated interrupt service
routine.
Symbols
22.5 REGISTER AND SYMBOL DEFINITION
The following abbreviations represent the nomenclature
used in the instruction description and the COP8 crossassembler.
[B]
Memory Indirectly Addressed by B Register
[X]
Memory Indirectly Addressed by X Register
MD
Direct Addressed Memory
Mem
Direct Addressed Memory or [B]
Meml
Direct Addressed Memory or [B] or
Immediate Data
Registers
A
8-Bit Accumulator Register
Imm
8-Bit Immediate Data
B
8-Bit Address Register
Reg
X
8-Bit Address Register
Register Memory: Addresses F0 to FF
(Includes B, X and SP)
S
8-Bit Segment Register
SP
8-Bit Stack Pointer Register
Bit
←
Loaded with
PC
15-Bit Program Counter Register
↔
Exchanged with
PU
Upper 7 Bits of PC
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72
Bit Number (0 to 7)
COP8AME9
22.0 Instruction Set
(Continued)
22.6 INSTRUCTION SET SUMMARY
A←A + Meml
A←A + Meml + C, C←Carry,
HC←Half Carry
ADD
A,Meml
ADD
ADC
A,Meml
ADD with Carry
SUBC
A,Meml
Subtract with Carry
A←A − MemI + C, C←Carry,
HC←Half Carry
AND
A,Meml
Logical AND
A←A and Meml
ANDSZ
A,Imm
Logical AND Immed., Skip if Zero
Skip next if (A and Imm) = 0
OR
A,Meml
Logical OR
XOR
A,Meml
Logical EXclusive OR
A←A or Meml
A←A xor Meml
IFEQ
MD,Imm
IF EQual
Compare MD and Imm, Do next if MD = Imm
IFEQ
A,Meml
IF EQual
Compare A and Meml, Do next if A = Meml
Compare A and Meml, Do next if A ≠ Meml
IFNE
A,Meml
IF Not Equal
IFGT
A,Meml
IF Greater Than
IFBNE
#
If B Not Equal
Compare A and Meml, Do next if A > Meml
Do next if lower 4 bits of B ≠ Imm
DRSZ
Reg
Decrement Reg., Skip if Zero
Reg←Reg − 1, Skip if Reg = 0
SBIT
#,Mem
Set BIT
1 to bit, Mem (bit = 0 to 7 immediate)
RBIT
#,Mem
Reset BIT
0 to bit, Mem
IFBIT
#,Mem
IF BIT
If bit #,A or Mem is true do next instruction
RPND
Reset PeNDing Flag
Reset Software Interrupt Pending Flag
EXchange A with Memory
A↔Mem
X
A,Mem
X
A,[X]
EXchange A with Memory [X]
A↔[X]
LD
A,Meml
LoaD A with Memory
LD
A,[X]
LoaD A with Memory [X]
A←Meml
A←[X]
LD
B,Imm
LoaD B with Immed.
B←Imm
LD
Mem,Imm
LoaD Memory Immed.
LD
Reg,Imm
LoaD Register Memory Immed.
Mem ←Imm
Reg←Imm
X
A, [B ± ]
EXchange A with Memory [B]
X
A, [X ± ]
EXchange A with Memory [X]
LD
A, [B ± ]
LoaD A with Memory [B]
LD
A, [X ± ]
LoaD A with Memory [X]
LD
[B ± ],Imm
LoaD Memory [B] Immed.
CLR
A
CLeaR A
INC
A
INCrement A
DEC
A
DECrement A
LAID
A↔[B], (B←B ± 1)
A↔[X], (X←X ± 1)
A←[B], (B←B ± 1)
A←[X], (X←X ± 1)
[B]←Imm, (B←B ± 1)
A←0
A←A + 1
A←A − 1
A←ROM (PU,A)
A←BCD correction of A (follows ADC, SUBC)
C→A7→…→A0→C
Load A InDirect from ROM
DCOR
A
Decimal CORrect A
RRC
A
Rotate A Right thru C
RLC
A
Rotate A Left thru C
C←A7←…←A0←C, HC←A0
SWAP
A
SWAP nibbles of A
SC
Set C
A7…A4↔A3…A0
C←1, HC←1
RC
Reset C
C←0, HC←0
IFC
IF C
IF C is true, do next instruction
IF Not C
If C is not true, do next instruction
SP←SP + 1, A←[SP]
[SP]←A, SP←SP − 1
IFNC
POP
A
POP the stack into A
PUSH
A
PUSH A onto the stack
JMPL
Addr.
Jump absolute Long
JMP
Addr.
Jump absolute
PU←[VU], PL←[VL]
PC←ii (ii = 15 bits, 0 to 32k)
PC9…0←i (i = 12 bits)
JP
Disp.
Jump relative short
PC←PC + r (r is −31 to +32, except 1)
VIS
Vector to Interrupt Service Routine
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COP8AME9
22.0 Instruction Set
(Continued)
JSRL
Addr.
Jump SubRoutine Long
JSR
Addr.
Jump SubRoutine
JSRB
Addr
Jump SubRoutine Boot ROM
[SP]←PL, [SP−1]←PU,SP−2, PC←ii
[SP]←PL, [SP−1]←PU,SP−2, PC9…0←i
[SP]←PL, [SP−1]←PU,SP−2,
PL←Addr,PU←00, switch to flash
RET
RETurn from subroutine
RETSK
RETurn and SKip
PL←ROM (PU,A)
SP + 2, PL←[SP], PU←[SP−1]
SP + 2, PL←[SP],PU←[SP−1],
skip next instruction
SP + 2, PL←[SP],PU←[SP−1],GIE←1
JID
Jump InDirect
RETI
RETurn from Interrupt
INTR
Generate an Interrupt
[SP]←PL, [SP−1]←PU, SP−2, PC←0FF
NOP
No OPeration
PC←PC + 1
22.7 INSTRUCTION EXECUTION TIME
Most instructions are single byte (with immediate addressing
mode instructions taking two bytes).
Instructions Using A & C
Most single byte instructions take one cycle time to execute.
Skipped instructions require x number of cycles to be
skipped, where x equals the number of bytes in the skipped
instruction opcode.
See the BYTES and CYCLES per INSTRUCTION table for
details.
Bytes and Cycles per Instruction
The following table shows the number of bytes and cycles for
each instruction in the format of byte/cycle.
Arithmetic and Logic Instructions
[B]
Direct
Immed.
ADD
1/1
3/4
2/2
ADC
1/1
3/4
2/2
SUBC
1/1
3/4
2/2
AND
1/1
3/4
2/2
OR
1/1
3/4
2/2
CLRA
1/1
INCA
1/1
DECA
1/1
LAID
1/3
DCORA
1/1
RRCA
1/1
RLCA
1/1
SWAPA
1/1
SC
1/1
RC
1/1
IFC
1/1
IFNC
1/1
PUSHA
1/3
POPA
1/3
ANDSZ
2/2
Transfer of Control Instructions
XOR
1/1
3/4
2/2
JMPL
3/4
IFEQ
1/1
3/4
2/2
JMP
2/3
IFGT
1/1
3/4
2/2
JP
1/3
IFBNE
1/1
JSRL
3/5
1/3
JSR
2/5
DRSZ
SBIT
1/1
3/4
JSRB
2/5
RBIT
1/1
3/4
JID
1/3
IFBIT
1/1
3/4
VIS
1/5
RET
1/5
RETSK
1/5
RETI
1/5
RPND
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1/1
74
INTR
1/7
NOP
1/1
COP8AME9
22.0 Instruction Set
(Continued)
Memory Transfer Instructions
Register
Indirect
Register Indirect
Direct
[B]
[X]
X A, (Note 17)
1/1
1/3
2/3
LD A, (Note
17)(Note 11)
1/1
1/3
2/3
Immed.
2/2
Auto Incr. & Decr.
[B+, B−]
[X+, X−]
1/2
1/3
1/2
1/3
LD B,Imm
1/1
(If B < 16)
LD B,Imm
2/2
(If B > 15)
LD Mem,Imm
2/2
3/3
LD Reg,Imm
2/3
IFEQ MD,Imm
3/3
2/2
Note 17: = > Memory location addressed by B or X or directly.
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76
JP−19 LD 0FC,#i
JP−18 LD 0FD,#i
JP−17 LD 0FE,#i
JP−16
JP−3
JP−2
JP−1
JP−0
* is an unused opcode
JP−20 LD 0FB,#i
LD 0FF,#i
LD 0F9,#i
LD 0F8,#i
JP−4
LD 0F7,#i
LD 0F6,#i
JP−21 LD 0FA,#i
JP−25
JP−9
LD 0F5,#i
JP−5
JP−26
JP−10
LD 0F4,#i
JP−22
JP−27
JP−11
LD 0F3,#i
JP−6
JP−28
JP−12
LD 0F2,#i
JP−23
JP−29
JP−13
LD 0F1,#i
JP−7
JP−30
JP−14
LD 0F0,#i
JP−24
JP−31
JP−15
D
JP−8
E
F
C
*
LD A,[X]
DIR
LD Md,#i
LD
A,[X−]
LD
A,[X+]
IFNE
A,[B]
NOP
*
X A,[X]
RPND
VIS
X A,[X−]
X A,[X+]
*
i is the immediate data
DRSZ
0FF
DRSZ
0FE
DRSZ
0FD
DRSZ
0FC
DRSZ
0FB
DRSZ
0FA
DRSZ
0F9
DRSZ
0F8
DRSZ
0F7
DRSZ
0F6
DRSZ
0F5
DRSZ
0F4
DRSZ
0F3
DRSZ
0F2
DRSZ
0F1
RRCA
B
(Continued)
DRSZ
0F0
22.0 Instruction Set
*
LD
A,[B]
JSRL
JMPL
LD
A,[B−]
LD
A,[B+]
IFEQ
Md,#i
RLCA
*
X A,[B]
JID
LAID
X
A,[B−]
X
A,[B+]
SC
RC
A
POPA
DECA
INCA
IFNC
IFC
OR
A,[B]
XOR
A,[B]
AND
A,[B]
ADD
A,[B]
IFGT
A,[B]
IFEQ
A,[B]
SUBC
A,[B]
ADC
A,[B]
8
RETI
RET
SBIT
7,[B]
SBIT
6,[B]
SBIT
5,[B]
SBIT
4,[B]
SBIT
3,[B]
SBIT
2,[B]
SBIT
1,[B]
SBIT
0,[B]
IFBIT
7,[B]
IFBIT
6,[B]
IFBIT
5,[B]
IFBIT
4,[B]
IFBIT
3,[B]
IFBIT
2,[B]
IFBIT
1,[B]
IFBIT
0,[B]
7
RBIT
7,[B]
RBIT
6,[B]
RBIT
5,[B]
RBIT
4,[B]
RBIT
3,[B]
RBIT
2,[B]
RBIT
1,[B]
RBIT
0,[B]
PUSHA
DCORA
SWAPA
CLRA
Reserved
Reserved
JSRB
ANDSZ
A,#i
6
Upper Nibble
Md is a directly addressed memory location
LD B,#i
LD [B],#i
LD A,Md RETSK
X A,Md
LD
[B−],#i
LD
[B+],#i
IFNE
A,#i
LD A,#i
OR A,#i
XOR
A,#i
AND
A,#i
ADD
A,#i
IFGT
A,#i
IFEQ
A,#i
SUBC
A,#i
ADC
A,#i
9
OPCODE TABLE
LD
B,#00
LD
B,#01
LD
B,#02
LD
B,#03
LD
B,#04
LD
B,#05
LD
B,#06
LD
B,#07
LD
B,#08
LD
B,#09
LD
B,#0A
LD
B,#0B
LD
B,#0C
LD
B,#0D
LD
B,#0E
LD
B,#0F
5
JSR
xF00–xFFF
JSR
xE00–xEFF
JSR
xD00–xDFF
JSR
xC00–xCFF
JSR
xB00–xBFF
JSR
xA00–xAFF
JSR
x900–x9FF
JSR
x800–x8FF
JSR
x700–x7FF
JSR
x600–x6FF
JSR
x500–x5FF
JSR
x400–x4FF
JSR
x300–x3FF
JSR
x200–x2FF
JSR
x100–x1FF
JSR
x000–x0FF
3
JMP
xF00–xFFF
JMP
xE00–xEFF
JMP
xD00–xDFF
JMP
xC00–xCFF
JMP
xB00–xBFF
JMP
xA00–xAFF
JMP
x900–x9FF
JMP
x800–x8FF
JMP
x700–x7FF
JMP
x600–x6FF
JMP
x500–x5FF
JMP
x400–x4FF
JMP
x300–x3FF
JMP
x200–x2FF
JMP
x100–x1FF
JMP
x000–x0FF
2
1
JP+32
JP+31
JP+30
JP+29
JP+28
JP+27
JP+26
JP+25
JP+24
JP+23
JP+22
JP+21
JP+20
JP+19
JP+18
JP+17
The opcode 60 Hex is also the opcode for IFBIT #i,A
IFBNE 0F
IFBNE 0E
IFBNE 0D
IFBNE 0C
IFBNE 0B
IFBNE 0A
IFBNE 9
IFBNE 8
IFBNE 7
IFBNE 6
IFBNE 5
IFBNE 4
IFBNE 3
IFBNE 2
IFBNE 1
IFBNE 0
4
JP+16
JP+15
JP+14
JP+13
JP+12
JP+11
JP+10
JP+9
JP+8
JP+7
JP+6
JP+5
JP+4
JP+3
JP+2
INTR
0
F
E
D
C
B
A
9
8
7
6
5
4
3
2
1
0
COP8AME9
Lower Nibble
23.1 TOOLS ORDERING NUMBERS FOR THE COP8S/C/A FLASH FAMILY DEVICES
This section provides specific tools ordering information for the devices in this datasheet, followed by a summary of the tools and
development kits available at print time. Up-to-date information, device selection guides, demos, updates, and purchase
information can be obtained at our web site at: www.national.com/cop8.
Unless otherwise noted, tools can be purchased for worldwide delivery from National’s e-store: http://www.national.com/
store/
Tool
Order Number
Cost*
Notes/Includes
Free
Assembler/ Linker/ Simulators/ Library Manager/
Compiler Demos/ Flash ISP and NiceMon Debugger
Utilities/ Example Code/ etc.
(Flash Emulator support requires licensed COP8-NSDEV
CD-ROM).
Hardware
COP8-REF-FL1
Reference Designs
VL
For COP8Flash Sx/Cx - Demo Board and Software;
44PLCC Socket; Stand-alone, or use as development target
board with Flash ISP and/or COP8Flash Emulator. Does not
include COP8 development software.
COP8-REF-AM
VL
For COP8Flash AME - Demo Board and Software; 28DIP
Socket. Stand alone, or use as development target board
with Flash ISP and/or COP8Flash Emulator. Does not
include COP8 development software.
COP8-SKFLASH-01
VL
Supports COP8Sx/Cx/AME - Target board with 68PLCC
COP8CDR9, 44PLCC and 28DIP sockets, LEDs, Test
Points, and Breadboard Area. Development CD, ISP Cable,
Debug Software and Source Code. No p/s. Also supports
COP8Flash Emulators and Kanda ISP Tool.
COP8-REF-FL1 or -AM
VL
COP8Flash Hardware Reference Design boards can also be
used as Development Target boards, with ISP and Emulator
onboard connectors.
Evaluation Software and Reference Designs
Software and
Utilities
Web Downloads:
www.national.com/cop8
Starter Kits and Hardware Target Boards
Starter
Development Kits
Software Development Languages, and Integrated Development Environments
National’s WCOP8 COP8-NSDEV
IDE and Assembler
on CD
$3
Fully Licensed IDE with Assembler and
Emulator/Debugger Support. Assembler/ Linker/ Simulator/
Utilities/ Documentation. Updates from web. Included with
SKFlash, COP8 Emulators, COP8-PM.
COP8 Library
www.kkd.dk/libman.htm
Manager from KKD
Eval
The ultimate information source for COP8 developers Integrates with WCOP8 IDE. Organize and manage code,
notes, datasheets, etc.
WEBENCH Online www.national.com
Graphical
/webench
Application Builder
With Unis
Processor Expert
COP8-SW-PE2
Free
Online Graphical IDE, featuring UNIS Processor Expert(
Code Development Tool with Simulator - Develop
applications, simulate and debug, download working code.
Online project manager.
L
Graphical IDE and Code Development Tool with
Simulator - Stand-alone, enhanced PC version of our
WEBENCH tools on CD.
Byte Craft C
Compiler
COP8-SW-COP8C
COP8-SW-COP8CW
M
H
DOS/16bit Version - No IDE.
Win 32 Version with IDE.
IAR Embedded
Workbench Tool
Set.
COP8-SW-EWCOP8
EWCOP8-BL
Assembler-Only Version
H
M
Free
Complete tool set, with COP8 Emulator/Debugger support.
Baseline version - Purchase from IAR only.
Assembler only; No COP8 Emulator/Debugger support.
Hardware Emulation and Debug Tools
77
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COP8AME9
23.0 Development Support
COP8AME9
23.0 Development Support
(Continued)
Hardware
Emulators
COP8-EMFlash-00
COP8-DMFlash-00
COP8-IMFlash-00
L
M
H
Includes 110v/220v p/s, target cable with 2x7 connector, 68
pin COP8CDR9 Null Target, manuals and software on CD.
- COP8AME uses optional 28 pin Null Target
(COP8-EMFA-28N).
- Add PLCC Target Package Adapter if needed.
Emulator Null
Target
COP8-EMFA-68N
COP8-EMFA-28N
VL
VL
68 pin PLCC COP8CDR9; Included in COP8-EM/DM/IM
Flash.
28pin DIP COP8AME9; Must order seperately.
Emulator Target
Package Adapters
COP8-EMFA-44P
VL
44 pin PLCC target package adapter. (Use instead of 2x7
emulator header)
COP8-EMFA-68P
VL
68 pin PLCC target package adapter. (Use instead of 2x7
emulator header)
COP8-SW-NMON
Free
Download code and Monitor S/W for single-step debugging
via Microwire. Includes PC control/debugger software and
monitor program.
NiceMon Debug
Monitor Utility
Development and Production Programming Tools
National’s
Approved
Programmers
Third party programmers
Programming
Adapters
(For any
programmer
supporting flash
adapter base
pinout)
COP8-PGMA-28DF1
L
For programming 28DIP COP8AME only.
COP8-PGMA-28SF1
L
For programming 28SOIC COP8AME only.
COP8-PGMA-44PF1
L
For programming all 44PLCC COP8FLASH.
COP8-PGMA-44CSF
L
For programming all 44LLP COP8FLASH.
COP8-PGMA-48TF1
L
For programming all 48TSSOP COP8 FLASH.
COP8-PGMA-68PF1
L
For programming all 68PLCC COP8FLASH
COP8-PGMA-56TF1
L
For programming all 56TSSOP COP8FLASH.
KANDA’s Flash
ISP Programmer
COP8 USB ISP
www.kanda.com
L
USB connected Dongle, with target cable and Control
Software; Updateable from the web; Purchase from
www.kanda.com
SofTec Micro ISP
Programmer
inDart-COP8
Development
Devices
COP8CBR9/CCR9/CDR9
COPCBE9/CCE9
COP8SBR/SCR9/SDR9
COP8SBE/SCE
COP8AME9
Download a current list of approved third party
programmers.
Purchase from www.softecmicro.com
Free
All packages. Obtain samples from: www.national.com
*Cost: Free; VL= < $100; L=$100-$300; M=$300-$1k; H=$1k-$3k; VH=$3k-$5k
www.national.com
78
(Continued)
23.2 COP8 TOOLS OVERVIEW
COP8 Evaluation Software and Reference Designs Software and Hardware for: Evaluation of COP8 Development Environments; Learning about COP8 Architecture and
Features; Demonstrating Application Specific Capabilities.
Product
Description
Source
WCOP8 IDE and
Software
Downloads
Software Evaluation downloads for Windows. Includes WCOP8 IDE evaluation
version, Full COP8 Assembler/Linker, COP8-SIM Instruction Level Simulator or Unis
Simulator, Byte Craft COP8C Compiler Demo, IAR Embedded Workbench
(Assembler version), Manuals, Applications Software, and other COP8 technical
information.
www.cop8.com
FREE Download
COP8 Hardware
Reference
Designs
Reference Designs for COP8 Families. Realtime hardware environments with a
variety of functions for demonstrating the various capabilities and features of specific
COP8 device families. Run Windows demo reference software, and exercise
specific device capabilities. Also can be used as a realtime target board for code
development, with our flash development tools.
(Add our COP8Flash Emulator, or our COP8-NSDEV CD with your ISP cable for a
complete low-cost development system.)
NSC Distributor,
or Order from:
www.cop8.com
COP8 Starter Kits and Hardware Target Solutions Hardware Kits for: In-depth Evaluation and Testing of COP8 capabilities; Developing and Testing Code; Implementing
Target Design.
Product
Description
Source
COP8 Flash
Starter Kits
Flash Starter Kit - A complete Code Development Tool for COP8Flash Families. A
Windows IDE with Assembler, Simulator, and Debug Monitor (does not support
COP8TAx devices), combined with a simple realtime target environment. Quickly
design and simulate your code, then download to the target COP8flash device for
execution and simple debugging. Includes a library of software routines, and source
code. No power supply.
(Add a COP8-EMFlash Emulator for advanced emulation and debugging)
NSC Distributor,
or Order from:
www.cop8.com
COP8 Hardware
Reference
Designs
Preconfigured realtime hardware environments with a variety of onboard I/O and
display functions. Modify the reference software, or develop your own code. Boards
support our COP8 ISP Utility, NiceMon Flash Debug Monitor, and our COP8Flash
Emulators.
NSC Distributor,
or Order from:
www.cop8.com
COP8 Software Development Languages and Integrated Environments Integrated Software for: Project Management; Code Development; Simulation and Debug.
Product
Description
WCOP8 IDE
from National on
CD-ROM
National’s COP8 Software Development package for Windows on CD. Fully licensed
versions of our WCOP8 IDE and Emulator Debugger, with Assembler/ Linker/
Simulators/ Library Manager/ Compiler Demos/ Flash ISP and NiceMon Debugger
Utilities/ Example Code/ etc. Includes all COP8 datasheets and documentation.
Included with most tools from National.
NSC Distributor,
or Order from:
www.cop8.com
Unis Processor
Expert
Processor Expert( from Unis Corporation - COP8 Code Generation and Simulation
tool with Graphical and Traditional user interfaces. Automatically generates
customized source code "Beans" (modules) containing working code for all on-chip
features and peripherals, then integrates them into a fully functional application code
design, with all documentation.
Unis, or Order
from:
www.cop8.com
Byte Craft
COP8C Compiler
ByteCraft COP8C- C Cross-Compiler and Code Development System. Includes
BCLIDE (Integrated Development Environment) for Win32, editor, optimizing C
Cross-Compiler, macro cross assembler, BC-Linker, and MetaLinktools support.
(DOS/SUN versions available; Compiler is linkable under WCOP8 IDE)
ByteCraft
Distributor,
or Order from:
www.cop8.com
IAR Embedded
Workbench
IAR EWCOP8 - ANSI C-Compiler and Embedded Workbench. A fully integrated
Win32 IDE, ANSI C-Compiler, macro assembler, editor, linker, librarian, and C-Spy
high-level simulator/debugger. (EWCOP8-M version includes COP8Flash Emulator
support) (EWCOP8-BL version is limited to 4k code limit; no FP).
IAR Distributor,
or Order from:
www.cop8.com
79
Source
www.national.com
COP8AME9
23.0 Development Support
COP8AME9
23.0 Development Support
(Continued)
COP8 Hardware Emulation/Debug Tools Hardware Tools for: Real-time Emulation; Target Hardware Debug; Target Design Test.
Product
Description
Source
COP8Flash
Emulators COP8-EMFlash
COP8-DMFlash
COP8-IMFlash
COP8 In-Circuit Emulator for Flash Families. Windows based development and
real-time in-circuit emulation tool, with trace (EM=None; DM/IM=32k), s/w
breakpoints (DM=16, EM/IM=32K), source/symbolic debugger, and device
programming. Includes COP8-NSDEV CD, 68pin Null Target, emulation cable with
2x7 connector, and power supply.
NSC Distributor,
or Order from:
www.cop8.com
NiceMon Debug
Monitor Utility
A simple, single-step debug monitor with one breadpoint. MICROWIRE interface.
Download from:
www.cop8.com
Development and Production Programming Tools Programmers for: Design Development; Hardware Test; Pre-Production; Full Production.
Product
Description
Source
COP8 Flash
Emulators
COP8 Flash Emulators include in-circuit device programming capability during
development.
NSC Distributor, or
Order from:
www.cop8.com
NiceMon
Debugger,
KANDAFlash
National’s software Utilities "KANDAFlash" and "NiceMon" provide development
In-System-Programming for our Flash Starter Kit, our Prototype Development
Board, or any other target board with appropriate connectors.
Download from:
www.cop8.com
KANDA COP8
USB ISP
The COP8 USB ISP programmer from KANDA is available for engineering, and
small volume production use. USB interface.
www.kanda.com
SofTec Micro
inDart COP8
The inDart COP8 programmer from SofTec Micro is available for engineering
and small volume production use. PC serial interface only.
www.softecmicro.com
Third-Party
Programmers
Third-party programmers and automatic handling equipment are approved for
non-ISP engineering and production use.
Various Vendors
Factory
Programming
Factory programming available for high-volume requirements.
National
Representative
23.3 WHERE TO GET TOOLS
Tools can be ordered directly from National, National’s e-store (Worldwide delivery: http://www.national.com/store/) , a National
Distributor, or from the tool vendor. Go to the vendor’s web site for current listings of distributors.
Vendor
Byte Craft Limited
Home Office
Electronic Sites
421 King Street North
www.bytecraft.com
Waterloo, Ontario
[email protected]
Other Main Offices
Distributors Worldwide
Canada N2J 4E4
Tel: 1-(519) 888-6911
Fax: (519) 746-6751
IAR Systems AB
PO Box 23051
www.iar.se
USA:: San Francisco
S-750 23 Uppsala
[email protected]
Tel: +1-415-765-5500
Sweden
[email protected]
Fax: +1-415-765-5503
Tel: +46 18 16 78 00
[email protected]
UK: London
Fax +46 18 16 78 38
[email protected]
Tel: +44 171 924 33 34
Fax: +44 171 924 53 41
Germany: Munich
Tel: +49 89 470 6022
Fax: +49 89 470 956
Embedded Results
LTD.
www.national.com
P.O. Box 200
Aberystwyth,
SY23 2WD, UK
Tel/Fax: +44 (0)8707 446 807
www.kanda.com
[email protected]
[email protected]
80
USA:
Tel/Fax: 800-510-3609
[email protected]
www.ucpros.com
Vendor
(Continued)
Home Office
K and K
Development ApS
Kaergaardsvej 42 DK-8355
Solbjerg Denmark
Fax: +45-8692-8500
Electronic Sites
Other Main Offices
www.kkd.dk [email protected]
National
2900 Semiconductor Dr.
www.national.com/cop8
Europe:
Semiconductor
Santa Clara, CA 95051
support @nsc.com
Tel: 49(0) 180 530 8585
USA
[email protected]
Tel: 1-800-272-9959
Fax: 49(0) 180 530 8586
Hong Kong:
Fax: 1-800-737-7018
Distributors Worldwide
SofTec Microsystems Via Roma, 1
33082 Azzano Decimo (PN)
Italy
Tel: +39 0434 640113
Fax: +39 0434 631598
[email protected]
www.softecmicro.com
[email protected]
Germany:
Tel.:+49 (0) 8761 63705
France:
Tel: +33 (0) 562 072 954
UK:
Tel: +44 (0) 1970 621033
The following companies have approved COP8 programmers in a variety of configurations. Contact your vendor’s local office
or distributor and request a COP8FLASH update. You can link to their web sites and get the latest listing of approved
programmers at: www.national.com/cop8.
Advantech; BP Microsystems; Data I/O; Dataman; Hi-Lo Systems; KANDA, Lloyd Research; MQP; Needhams; Phyton; SofTec
Microsystems; System General; and Tribal Microsystems.
24.0 Revision History
Date
Section
Summary of Changes
January 2002
Forced Execution from
Boot ROM.
April 2002
Timers
Clarification on high speed PWM Timer use.
Development Support
Updated with the latest support information.
Pin Descriptions
Clarification of the functions of L4 and L6 for T2 and T3 PWM Output.
February 2004
Added Figure.
Reset
Addition of caution regarding rising edge on RESET with low VCC.
Power Saving Features
Description of modified function of ITMR Register.
General
Deleted references to COP8ANE9, COP8SDE9 and COP8CFE9 devices
which have been placed on Lifetime Buy. Removed temp range 7, −40˚C to
+125˚C
Electrical Specifications
Updated A/D specifications to match production values
Eliminated references to non-brownout devices.
General update of electrical specifications.
RESET
Eliminated references to non-brownout devices.
Timers
Incorporated High Speed Timer/Port L interaction description from User
Information Sheet
Development Support
Additional update to current support.
81
www.national.com
COP8AME9
23.0 Development Support
COP8AME9
25.0 Physical Dimensions
inches (milli-
meters) unless otherwise noted
Molded SO Wide Body Package (MW)
Order Number COP8AME9EMW8
NS Package Number M28B
Molded Dual-In-Line Package (N)
Order Number COP8AME9ENA8
NS Package Number N28B
www.national.com
82
LIFE SUPPORT POLICY
NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL
COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:
1. Life support devices or systems are devices or
systems which, (a) are intended for surgical implant
into the body, or (b) support or sustain life, and
whose failure to perform when properly used in
accordance with instructions for use provided in the
labeling, can be reasonably expected to result in a
significant injury to the user.
2. A critical component is any component of a life
support device or system whose failure to perform
can be reasonably expected to cause the failure of
the life support device or system, or to affect its
safety or effectiveness.
BANNED SUBSTANCE COMPLIANCE
National Semiconductor certifies that the products and packing materials meet the provisions of the Customer Products
Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification
(CSP-9-111S2) and contain no ‘‘Banned Substances’’ as defined in CSP-9-111S2.
National Semiconductor
Americas Customer
Support Center
Email: [email protected]
Tel: 1-800-272-9959
www.national.com
National Semiconductor
Europe Customer Support Center
Fax: +49 (0) 180-530 85 86
Email: [email protected]
Deutsch Tel: +49 (0) 69 9508 6208
English Tel: +44 (0) 870 24 0 2171
Français Tel: +33 (0) 1 41 91 8790
National Semiconductor
Asia Pacific Customer
Support Center
Email: [email protected]
National Semiconductor
Japan Customer Support Center
Fax: 81-3-5639-7507
Email: [email protected]
Tel: 81-3-5639-7560
National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.
COP8AME9 8-Bit CMOS Flash Based Microcontroller with 8k Memory, Dual Op Amps, Virtual
EEPROM, Temperature Sensor, 10-Bit A/D and Brownout Reset
Notes