COP8SG Family
8-Bit CMOS ROM Based and OTP Microcontrollers with
8k to 32k Memory, Two Comparators and USART
General Description
The COP8SG Family ROM and OTP based microcontrollers
are highly integrated COP8
to 32k memory and advanced features including Analog
comparators, and zero external components. These singlechip CMOS devices are suited for more complex applications requiring a full featured controller with larger memory,
low EMI, two comparators, and a full-duplex USART.
COP8SGx7 devices are 100% form-fit-function compatible
OTP (One Time Programmable) versions for use in production or development of the COP8SGx5 ROM.
™
Feature core devices with 8k
Erasable windowed versions (Q3) are available for use with
a range of COP8 software and hardware development tools.
Family features include an 8-bit memory mapped architecture, 15 MHz CKI with 0.67 µs instruction cycle, 14 interrupts, three multi-function 16-bit timer/counters with PWM,
full duplex USART, MICROWIRE/PLUS
parators, two power saving HALT/IDLE modes, MIWU, idle
timer, on-chip R/C oscillator, high current outputs, user selectable options (WATCHDOG
power-on-reset), 2.7V to 5.5V operation, program code security, and 28/40/44 pin packages.
Devices included in this datasheet are:
™
™
, two analog com-
, 4 clock/oscillator modes,
COP8SG Family, 8-Bit CMOS ROM Based and OTP Microcontrollers with 8k to 32k Memory, Two
n Low cost 8-bit microcontroller
n Quiet Design (low radiated emissions)
n Multi-Input Wakeup pins with optional interrupts (8 pins)
n Mask selectable clock options
n Internal Power-On-Reset—user selectable
n WATCHDOG and Clock Monitor Logic —user selectable
n Eight high current outputs
n 256 or 512 bytes on-board RAM
n 8k to 32k ROM or OTP EPROM with security feature
CPU Features
n Versatile easy to use instruction set
n 0.67 µs instruction cycle time
COP8™is a trademark of National Semiconductor Corporation.
RAM
(bytes)
I/O PinsPackagesTemperature
28 DIP/SOIC, 40 DIP,
44 PLCC/QFP/CSP
28 DIP/SOIC, 40 DIP,
44 PLCC/QFP/CSP
28 DIP/SOIC, 40 DIP,
44 PLCC/QFP/CSP
28 DIP/SOIC, 40 DIP,
44 PLCC/QFP/CSP
28 DIP/SOIC, 40 DIP,
44 PLCC/QFP/CSP
28 DIP/SOIC, 40 DIP,
44 PLCC/QFP/CSP
28 DIP/SOIC, 40 DIP,
44 PLCC/QFP/CSP
n Fourteen multi-source vectored interrupts servicing
— External interrupt / Timers T0 — T3
— MICROWIRE/PLUS Serial Interface
— Multi-Input Wake Up
— Software Trap
— USART (2; 1 receive and 1 transmit)
— Default VIS (default interrupt)
n 8-bit Stack Pointer SP (stack in RAM)
n Two 8-bit Register Indirect Data Memory Pointers
n True bit manipulation
n BCD arithmetic instructions
-40 to +85˚C,
-40 to +125˚C
-40 to +85˚C,
-40 to +125˚C
-40 to +85˚C,
-40 to +125˚C
-40 to +85˚C,
-40 to +125˚C
-40 to +85˚C,
-40 to +125˚C
-40 to +85˚C,
-40 to +125˚C
-40 to +85˚C,
-40 to +125˚C
Peripheral Features
n Multi-Input Wakeup Logic
n Three 16-bit timers (T1 — T3), each with two 16-bit
n Idle Timer (T0)
n MICROWIRE/PLUS Serial Interface (SPI Compatible)
n Full Duplex USART
n Two Analog Comparators
COP8SG Family
I/O Features
n Software selectable I/O options (TRI-STATE
Output,Push-Pull Output, Weak Pull-Up Input, and High
Impedance Input)
n Schmitt trigger inputs on ports G and L
n Eight high current outputs
n Packages: 28 SO with 24 I/O pins, 40 DIP with 36 I/O
pins, 44 PLCC, PQFP and CSP with 40 I/O pins
Block Diagram
Fully Static CMOS Design
n Low current drain (typically<4 µA)
n Two power saving modes: HALT and IDLE
Temperature Range
n −40˚C to +85˚C, −40˚C to +125˚C
®
Development Support
n Windowed packages for DIP and PLCC
n Real time emulation and debug tools available
FIGURE 1. COP8SGx Block Diagram
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10131744
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1.0 Device Description
1.1 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 or EPROM, while data memory is usually
RAM. Consequently 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 single-address bus
architecture.
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.
1.2 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 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. 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.
1.2.1 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.
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.
1.2.2 Many Single-Byte, Multifunction 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 post-
incrementing and post-decrementing, to name just a few
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: (LoadAccumulator-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 programmemory for checksum
calculations.
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 (analogous to “FOR NEXT” in
higher level languages).
1.2.3 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
ability to set, reset and test any individual bit in the data
memory addressspace, including memory-mappedI/O ports
and associated registers.
1.2.4 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-maped registers allow designers to optimize the precise implementation of certain
specific instructions.
1.3 EMI REDUCTION
The COP8SGx5 family of devices 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
I
smoothing filters, to help circumvent many of the EMI
CC
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.
1.4 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.
The COP8family offers a wide range of packages and do not
waste pins: up to 90.9% (or 40 pins in the 44-pin package)
are devoted to useful I/O.
COP8SG Family
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Connection Diagrams
COP8SG Family
Top View
10131704
Order Number COP8SGXY28M8
See NS Package Number M28B
Order Number COP8SGXY28N8
See NS Package Number N28B
Order Number COP8SGR728Q3
See NS Package Number D28JQ
Top View
10131753
Order Number COP8SGR7HLQ8
See NS Package Number LQA44A
10131705
Top View
Order Number COP8SGXY40N8
See NS Package Number N40A
Order Number COP8SGR5740Q3
See NS Package Number D40KQ
Top View
10131706
Order Number COP8SGXY44V8
See NS Package Number V44A
Order Number COP8SGR744J3
See NS Package Number EL44C
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Top View
10131743
Order Number COP8SGXYVEJ8
See NS Package Number VEJ44A
Note 1: X = E for 8k, G for 16k,
H for 20k, K for 24k, R for 32k
Y = 5 for ROM, 7 for OTP
Page 5
Pinouts for 28 -, 40- and 44-Pin Packages
PortTypeAlt. Fun
L0I/OMIWU1117171112
L1I/OMIWU or CKX1218181213
L2I/OMIWU or TDX1319191314
L3I/OMIWU or RDX1420201415
L4I/OMIWU or T2A1521251920
L5I/OMIWU or T2B1622262021
L6I/OMIWU or T3A1723272122
L7I/OMIWU or T3B1824282223
G0I/OINT2535393334
G1I/OWDOUT*2636403435
G2I/OT1B2737413536
G3I/OT1A2838423637
G4I/OSO1334142
G5I/OSK2444243
G6ISI3554344
G7ICKO466441
D0O1925292324
D1O2026302425
D2O2127312526
D3O2228322627
D4O29332728
D5O30342829
D6O31352930
D7O32363031
F0I/O79934
F1I/OCOMP1IN−8101045
F2I/OCOMP1IN+9111156
F3I/OCOMP1OUT10121267
F4I/OCOMP2IN−131378
F5I/OCOMP2IN+141489
F6I/OCOMP2OUT1515910
F7I/O16161011
C0I/O39433738
C1I/O40443839
C2I/O113940
C3I/O224041
C4I/O211516
C5I/O221617
C6I/O231718
C7I/O241819
V
CC
GND2333373132
CKII57712
RESET
* G1 operation as WDOUT is controlled by ECON bit 2.
I2434383233
28-Pin
SO
68 823
40-Pin DIP
44-Pin
PLCC
44-Pin PQFP44-Pin CSP
COP8SG Family
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2.1 Ordering Information
COP8SG Family
10131708
FIGURE 2. Part Numbering Scheme
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Page 7
COP8SG Family
3.0 Electrical Characteristics
Total Current out of
GND Pin (Sink)110 mA
Absolute Maximum Ratings
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Supply Voltage (V
Voltage at Any Pin−0.3V to V
Total Current into V
)7V
CC
CC
(Note 2)
+0.3V
CC
Storage Temperature
Range−65˚C to +140˚C
ESD Protection Level2kV (Human Body
Model)
Note 2:
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.
Pin (Source)100 mA
DC Electrical Characteristics
−40˚C ≤ TA≤ +85˚C unless otherwise specified.
ParameterConditionsMinTypMaxUnits
Operating Voltage2.75.5V
Power Supply Rise Time1050 x 10
V
Start Voltage to Guarantee POR00.25V
CC
Power Supply Ripple (Note 4)Peak-to-Peak0.1 V
Supply Current (Note 5)
CKI = 15 MHzV
CKI = 10 MHzV
CKI = 4 MHzV
HALT Current (Note 6)V
= 5.5V, tC= 0.67 µs9.0mA
CC
= 5.5V, tC= 1 µs6.0mA
CC
= 4.5V, tC= 2.5 µs2.1mA
CC
= 5.5V, CKI=0MHz
CC
<
410 µA
IDLE Current (Note 5)
CKI = 15 MHzV
CKI = 10 MHzV
CKI = 4 MHzV
Input Levels (V
IH,VIL
)
= 5.5V, tC= 0.67 µs2.25mA
CC
= 5.5V, tC= 1 µs1.5mA
CC
= 4.5V, tC= 2.5 µs0.8mA
CC
RESET
Logic High0.8 V
cc
Logic Low0.2 V
CKI, All Other Inputs
Logic High0.7 V
cc
Logic Low0.2 V
Internal Bias Resistor for the
0.512MΩ
Crystal/Resonator Oscillator
CKI Resistance to V
or GND when R/C
CC
VCC= 5.5V5811kΩ
Oscillator is selected
Hi-Z Input LeakageV
Input Pullup CurrentV
G and L Port Input HysteresisV
= 5.5V−2+2µA
CC
= 5.5V, VIN= 0V−40−250µA
CC
= 5.5V0.25 V
CC
cc
6
cc
cc
cc
ns
V
V
V
V
V
V
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Page 8
DC Electrical Characteristics (Continued)
−40˚C ≤ TA≤ +85˚C unless otherwise specified.
ParameterConditionsMinTypMaxUnits
Output Current Levels
D Outputs
COP8SG Family
SourceV
SinkV
All Others
Source (Weak Pull-Up Mode)V
Source (Push-Pull Mode)V
Sink (Push-Pull Mode)V
TRI-STATE LeakageV
Allowable Sink Current per Pin (Note 9)
D Outputs and L0 to L315mA
All Others3mA
Maximum Input Current without Latchup
(Note 7)
RAM Retention Voltage, Vr2.0V
V
Rise Time from a VCC≥ 2.0V(Note 10)12µs
CC
EPROM Data Retenton (Note 8), (Note 9)T
Input Capacitance(Note 9)7pF
Load Capacitance on D2(Note 9)1000pF
Note 4: Maximum rate of voltage change must be<0.5 V/ms.
Note 5: Supply and IDLE currents are measured with CKI driven with a square wave Oscillator, External Oscillator, inputs connected to V
but not connected to a load.
Note 6: The HALTmode will stop CKI from oscillating in the R/C and the Crystal configurations. In the R/C configuration, CKI is forced high internally.In the crystal
or external configuration, CKI is TRI-STATE. Measurement of I
programmed as low outputs and not driving a load; alloutputs programmed lowand not driving a load; all inputstied to V
to HALT mode entered via setting bit 7 of the G Port data register.
Note 7: Pins G6 and RESETare designed with a high voltage input network. These pins allowinput voltages
biased at voltages>VCC(the pins do not have source current when biased at a voltage below VCC). The effective resistance to VCCis 750Ω (typical). These two
pins will not latch up. The voltage at the pins must be limited to
ESD transients.
Note 8: National Semiconductor uses the High Temperature Storage Life (HTSL) test to evaluate the data retention capabilities of the EPROM memory cells used
in our OTP microcontrollers. Qualification devices have been stressed at 150˚C for 1000 hours. Under these conditions, our EPROM cells exhibit data retention
capabilities in excess of 29 years. This is based on an activation energy of 0.7eV derated to 55˚C.
Note 9: Parameter characterized but not tested.
Note 10: Rise times faster than the minimum specification may trigger an internal power-on-reset.
Note 11: MICROWIRE Setup and HoldTimesand Propagation Delays are referenced to theappropriate edge of the MICROWIRE clock. Seeand the MICROWIRE
operation description.
HALT is done with device neither sourcing nor sinking current; with L. F, C, G0, and G2–G5
DD
>
<
14V.WARNING: Voltages in excess of 14V will cause damage to the pins. This warning excludes
; clock monitor disabled. Parameter refers
CC
VCCand the pins will have sink current to VCCwhen
and outputs driven low
CC
Comparators AC and DC Characteristics
VCC= 5V, −40˚C ≤ TA≤ +85˚C.
ParameterConditionsMinTypMaxUnits
Input Offset Voltage (Note 12)0.4V ≤ V
≤ VCC− 1.5V
IN
±
5
Input Common Mode Voltage Range0.4V
Voltage Gain100dB
Low Level Output CurrentV
High Level Output CurrentV
= 0.4V−1.6mA
OL
OH=VCC
− 0.4V1.6mA
DC Supply Current per Comparator
(When Enabled)
Response Time (Note 13)200 mV step input
100 mV Overdrive,
100 pF Load
Comparator Enable Time(Note 14)600ns
Note 12: The comparator inputs are high impedance port inputs and, as such, input current is limited to port input leakage current.
Note 13: Response time is measured from astep input to a valid logic level at the comparator output. software response time is dependent of instruction execution.
Note 14: Comparator enable time is that delay time required between the end of the instruction cycle that enables the comparator and using the output of the
comparator, either by hardware or by software.
±
15mV
− 1.5V
CC
150µA
600ns
COP8SG Family
FIGURE 3. MICROWIRE/PLUS Timing
10131709
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Page 10
Absolute Maximum Ratings (Note 2)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
COP8SG Family
Supply Voltage (V
Voltage at Any Pin−0.3V to V
Total Current into V
)7V
CC
CC
CC
+0.3V
Storage Temperature
Range−65˚C to +140˚C
ESD Protection Level2kV (Human Body
Model)
Note 15:
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.
Pin (Source)100 mA
Total Current out of
GND Pin (Sink)110 mA
DC Electrical Characteristics
−40˚C ≤ TA≤ +125˚C unless otherwise specified.
ParameterConditionsMinTypMaxUnits
Operating Voltage4.55.5V
Power Supply Rise Time1050 x 10
V
Start Voltage to Guarantee POR00.25V
CC
Power Supply Ripple (Note 4)Peak-to-Peak0.1 V
Supply Current (Note 5)
CKI = 10 MHzV
CKI = 4 MHzV
HALT Current (Note 6)V
= 5.5V, tC= 1 µs6.0mA
CC
= 4.5V, tC= 2.5 µs2.1mA
CC
= 5.5V, CKI=0MHz
CC
<
410 µA
IDLE Current (Note 5)
CKI = 10 MHzV
CKI = 4 MHzV
Input Levels (V
IH,VIL
)
= 5.5V, tC= 1 µs1.5mA
CC
= 4.5V, tC= 2.5 µs0.8mA
CC
RESET
Logic High0.8 V
cc
Logic Low0.2 V
CKI, All Other Inputs
Logic High0.7 V
cc
Logic Low0.2 V
Internal Bias Resistor for the
0.512MΩ
Crystal/Resonator Oscillator
CKI Resistance to V
or GND when R/C
CC
VCC= 5.5V5811kΩ
Oscillator is selected
Hi-Z Input LeakageV
Input Pullup CurrentV
G and L Port Input HysteresisV
5
Input Common Mode Voltage Range0.4V
Voltage Gain100dB
Low Level Output CurrentV
High Level Output CurrentV
= 0.4V−1.6mA
OL
OH=VCC
− 0.4V1.6mA
DC Supply Current per Comparator
(When Enabled)
Response Time (Note 13)200 mV step input
100 mV Overdrive,
Comparator Enable Time600ns
±
25mV
− 1.5V
CC
150µA
600ns
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COP8SG Family
Typical Performance Characteristics T
1013174910131750
= 25˚C (unless otherwise specified)
A
1013175110131752
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4.0 Pin Descriptions
The COP8SGx 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
COP8SG Family
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.
V
and GND are the power supply pins. All VCCand GND
CC
pins must be connected.
CKI is the clock input. This can come from the Internal R/C
oscillator, external, or a crystal oscillator (in conjunction with
CKO). See Oscillator Description section.
RESET is the master reset input. See Reset description
section.
Each device contains four bidirectional 8-bit I/O ports (C, G,
L and F), where each individual bit 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 two associated 8-bit memory
mapped registers, the CONFIGURATION register and the
output DATA register. A memory mapped address is also
reserved for the input pins ofeach I/O port. (Seethe memory
map forthe various addressesassociated with theI/O ports.)
Figure 4
CONFIGURATION registers allow for each port bit to be
individually configured under software control as shown below:
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 Wakeup or T3B (Timer T3B Input)
L6 Multi-input Wakeup or T3A (Timer T3A Input)
L5 Multi-input Wakeup or T2B (Timer T2B Input)
L4 Multi-input Wakeup or T2A (Timer T2A Input)
L3 Multi-input Wakeup and/or RDX (USART Receive)
L2 Multi-input Wakeup or TDX (USART Transmit)
L1 Multi-input Wakeup and/or CKX (USART Clock)
L0 Multi-input Wakeup
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
shows the I/O port configurations. The DATA and
CONFIGURATION
Register
00Hi-Z Input
01Input with Weak Pull-Up
10Push-Pull Zero Output
11Push-Pull One Output
DATA
Register
Port Set-Up
(TRI-STATE Output)
dedicated WATCHDOG output with weak pullup if
WATCHDOG feature is selected by the Mask 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. Pin G7 is either input or
output depending on the oscillator option selected. With the
crystal oscillator option selected, G7 serves as the dedicated
output pin for the CKO clock output. With the internal R/C or
the external oscillator option selected, G7 serves as a general purpose Hi-Z input pin and is also used to bring the
device out of HALT mode with a low to high transition on G7.
Since G6 is an input only pin and G7 is the dedicated CKO
clock output pin (crystal clock option) or general purpose
input (R/Cor external clock option), the associated bitsin 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 zeroes.
Each device will be placed in the HALTmode by writing a “1”
to bit 7 of the Port G Data Register. Similarly the device 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. The G7 configuration bit, if set
high, enables the clock start up delay after HALT when the
R/C clock configuration is used.
Config. Reg.Data Reg.
G7CLKDLYHALT
G6Alternate SKIDLE
Port G has the following alternate features:
G7 CKO Oscillator dedicated output or general purpose
input
G6 SI (MICROWIRE Serial Data Input)
G5 SK (MICROWIRE Serial Clock)
G4 SO (MICROWIRE Serial Data Output)
G3 T1A (Timer T1 I/O)
G2 T1B (Timer T1 Capture Input)
G1 WDOUT WATCHDOG and/or CLock Monitor if WATCH-
DOG enabled, otherwise it is a general purpose I/O
G0 INTR (External Interrupt Input)
Port C is an 8-bit I/O port. The 40-pin device does not have
a full complement of Port C pins. The unavailable pins are
not terminated. A read operation on these unterminated pins
will return unpredictable values. The 28 pin device do not
offer Port C. On this device, the associated Port C Data and
Configuration registers should not be used.
Port F is an 8-bit I/O port. The 28--pin device does not have
a full complement of Port F pins. The unavailable pins are
not terminated. A read operation on these unterminated pins
will return unpredictable values.
Port F1–F3 are used forComparator 1. Port F4–F6 are used
for Comparator 2.
The Port F has the following alternate features:
F6 COMP2OUT (Comparator 2 Output)
F5 COMP2+IN (Comparator 2 Positive Input)
F4 COMP2-IN (Comparator 2 Negative Input)
F3 COMP1OUT (Comparator 1 Output)
F2 COMP1+IN (Comparator 1 Positive Input)
F1 COMP1-IN (Comparator 1 Negative Input)
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4.0 Pin Descriptions (Continued)
Note: For compatibility with existing software written for COP888xG devices
and with existing Mask ROM devices, a read of the Port I input pins
(address xxD7) will return the same data as reading the Port F input
pins (address xx96). It is recommended new applications whichwill go
to production with the COP8SGx use the Port F addresses. Note that
compatible ROM devices contains the input only Port I instead of the
bi-directional Port F.
Port D is an 8-bit output port that is preset highwhen RESET
goes low. The user can tie two or more D port outputs
(except D2) together in order to get a higher drive.
Note: Care must be exercised with the D2 pin operation. At RESET, the
external loads on this pin must ensure that the output voltages stay
above 0.7 V
keep the external loading on D2 to less than 1000 pF.
to prevent the chip from entering special modes. Also
CC
COP8SG Family
10131712
FIGURE 5. I/O Port Configurations — Output Mode
FIGURE 4. I/O Port Configurations
10131710
10131711
FIGURE 6. I/O Port Configurations — Input Mode
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5.0 Functional Description
The architecture of the devices are a modified Harvard architecture. With the Harvard architecture, the program
memory ROM is separated from the data store memory
(RAM). Both ROM and RAM have their own separate addressing space with separate address buses. The architec-
COP8SG Family
ture, though based on the Harvard architecture, permits
transfer of data from ROM to RAM.
5.1 CPU REGISTERS
The CPU can do an 8-bit addition, subtraction, logical or shift
operation in one instruction (t
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 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 02F Hex (devices with 64 bytes of RAM), or
initialized to RAM address 06F Hex (devices with 128 bytes
of RAM).
All the CPU registers are memory mapped with the exception of the Accumulator (A) and the Program Counter (PC).
5.2 PROGRAM MEMORY
The program memory consists of varies sizes of ROM.
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 0FF Hex. The contents of the program
memory read 00 Hex in the erased state. Program execution
starts at location 0 after RESET.
5.3 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 (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 256 or 512 bytes of RAM.
Sixteen bytes of RAM are mapped as “registers” at ad-
) cycle time.
C
dresses 0F0 to 0FE 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 and B are memory mapped
into this space at address locations 0FC to 0FE Hex respectively, with the other registers (except 0FF) 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.
5.4 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
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.
Figure 7
sion 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.
illustrates how the S register data memory exten-
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5.0 Functional Description (Continued)
COP8SG Family
FIGURE 7. RAM Organization
The instructions that utilize the stack pointer (SP) always
reference the stack as part of the base segment (Segment
0), regardlessof the contentsof the Sregister.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
112bytes 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. The additional 384 bytes of RAM in
this device are memory mapped at address locations 0100
to 017F, 0200 to 027F and 0300 to 037F hex.
Memory address ranges 0200 to 027F and 0300 to 037F are
unavailable on the COP8SGx5 and, if read, will return underfined data.
5.5 ECON (CONFIGURATION) REGISTER
For compatibility with COP8SGx7 devices, mask options are
defined by an ECON Configuration Register which is programmed at the same time as the program code. Therefore,
the register is programmed at the same time as the program
memory.
10131745
The format of the ECON register is as follows:
Bit 7Bit 6Bit 5Bit 4Bit 3Bit 2Bit 1Bit 0
XPOR SECURITY CKI 2 CKI 1 WATCHF-PortHALT
DOG
Bit 7= xThis is for factory test. The polarity is “Don’t
Care.”
Bit 6= 1Power-on reset enabled.
= 0Power-on reset disabled.
Bit 5= 1Security enabled.
Bits 4,3=0,0 External CKI option selected. G7 is avail-
able as a HALT restart and/or general purpose input. CKI is clock input.
= 0, 1 R/C oscillator option selected. G7 is avail-
able as a HALT restart and/or general purpose input. CKI clock input. Internal R/C
components are supplied for maximum R/C
frequency.
= 1, 0 Crystal oscillator with on-chip crystal bias
resistor disabled. G7 (CKO) is the clock
generator output to crystal/resonator.
= 1, 1 Crystal oscillator with on-chip crystal bias
resistor enabled.G7 (CKO) isthe clock generator output to crystal/resonator.
Bit 2= 1WATCHDOG feature disabled. G1 is a gen-
eral purpose I/O.
= 0WATCHDOG feature enabled. G1 pin is
WATCHDOG output with weak pullup.
Bit 1= 1Force port I compatibility. Disable port F
outputs and pull-ups. This is intended for
compatibility with existing code and Mask
ROMMed devices only. This bit should be
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Page 18
5.0 Functional Description (Continued)
programmed to 0 for all other applications.
= 0Enable full port F capability.
Bit 0= 1HALT mode disabled.
COP8SG Family
5.6 USER STORAGE SPACE IN EPROM
The ECON register is outside of the normal address range of
the ROM and can not be accessed by the executing software.
The COP8 assembler defines a special ROM section type,
CONF, into which the ECON may be coded. Both ECON and
User Data are programmed automatically by programmers
that are certified by National.
The following examples illustrate the declaration of ECON
and the User information.
Syntax:
[label:] .sectecon, conf
Example: The following sets a value in the ECON register
and User Identification for a COP8SGR728M7. The ECON
bit values shown select options: Power-on enabled, Security
disabled, Crystal oscillator with on-chip bias disabled,
WATCHDOG enabled and HALT mode enabled.
5.7 OTP SECURITY
The device has a security feature that, when enabled, prevents external reading of the OTP program memory. The
security bit in the ECON register determines, whether security is enabled or disabled. If the security feature is disabled,
the contents of the internal EPROM may be read.
If the security feature is enabled, then any attempt to
externally read the contents of the EPROM will result in
the value FF Hex being read from all program locations
Under no circumstances can a secured part be read. In
addition, with the security feature enabled, the write operation to the EPROM program memory and ECON register is
inhibited. The ECON register is readable regardless of the
state of the security bit. The security bit, when set, cannot
be erased, even in windowed packages. If the security bit
is setin a device in a windowed package, that device may be
erased but will not be further programmable.
If security is being used, it is recommended that all other bits
in the ECON register be programmed first.Then the security
bit can be programmed.
5.8 ERASURE CHARACTERISTICS
The erasure characteristics of the device are such that erasure begins to occur when exposed tolight with wavelengths
shorter than approximately 4000Angstroms (Å). It should be
noted that sunlight and certain types of fluorescent lamps
have wavelengths in the 3000Å - 4000Å range.
After programming, opaque labels should be placed over the
window of windowed devices to prevent unintentional erasure. Covering the window will also prevent temporary functional failure due to the generation of photo currents.
= 0HALT mode enabled.
.dbvalue;1 byte,
;configures options
.db<user information>
.endsect; up to 8 bytes
.sectecon, conf
.db0x55;por, xtal, wd, halt
.db'my v1.00' ;user data declaration
.endsect
The recommended erasure procedure for windowed devices
is exposure to short wave ultraviolet light which has a wavelength of 2537 Angstroms (Å). The integrated dose (i.e. UV
intensity X exposure time) for erasure should be a minimum
of 15W-sec/cm
2
.
5.9 RESET
The devices are initialized when the RESET pin is pulled low
or the On-chip Power-On Reset is enabled.
10131713
FIGURE 8. Reset Logic
The following occurs upon initialization:
Port L: TRI-STATE (High Impedance Input)
Port C: TRI-STATE (High Impedance Input)
Port G: TRI-STATE (High Impedance Input)
Port F: TRI-STATE (High Impedance Input)
Port D: HIGH
PC: CLEARED to 0000
PSW, CNTRL and ICNTRL registers: CLEARED
SIOR:
UNAFFECTED after RESETwith power already applied
RANDOM after RESET at power-on
T2CNTRL: CLEARED
T3CNTRL: CLEARED
Accumulator, Timer 1, Timer 2 and Timer 3:
RANDOM after RESET with crystal clock option
(power already applied)
UNAFFECTED after RESET with R/C clock option
(power already applied)
RANDOM after RESET at power-on
WKEN, WKEDG: CLEARED
WKPND: RANDOM
SP (Stack Pointer):
Initialized to RAM address 06F Hex
B and X Pointers:
UNAFFECTED after RESETwith power already applied
RANDOM after RESET at power-on
S Register: CLEARED
RAM:
UNAFFECTED after RESETwith power already applied
RANDOM after RESET at power-on
USART:
PSR, ENU, ENUR, ENUI: Cleared except the TBMT bit
which is set to one.
COMPARATORS:
CMPSL; CLEARED
WATCHDOG (if enabled):
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5.0 Functional Description (Continued)
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 t
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 t
the clock frequency reaching the minimum specified value,
at which time the G1 output will go high.
5.9.1 External 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. During Power-Up initialization, the user must ensure that the RESET pin is held
low until the device is within the specified VCCvoltage. An
R/C circuit on the RESET pin with a delay 5 times (5x)
greater than the power supply risetime or 15 µswhichever is
greater,is recommended. Reset should also bewide enough
to ensure crystal start-up upon Power-Up.
RESET may also be used to cause an exit from the HALT
mode.
A recommended reset circuit for this device is shown in
Figure 9
.
clock cycles. The Clock Monitor bit
C
–32 tCclock cycles following
C
RESET pin should be connected directly, or through a
pull-up resistor, to VCC. The output of the power-on reset
detector will always preset the Idle timer to 0FFF(4096 t
C
At this time, the internal reset will be generated.
If the Power-On Reset feature is enabled, 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 user is responsible for ensuring that V
CC
is at the
minimum level for the operating frequency within the 4096
t
. After the underflow, the logic is designed such that no
C
additional internal resets occur as long as V
CC
remains
above 2.0V.
The contents of data registers and RAM are unknown following the on-chip reset.
COP8SG Family
).
RC>5x power supply rise time or 15 µs, whichever is greater.
10131714
FIGURE 9. Reset Circuit Using External Reset
5.9.2 On-Chip Power-On Reset
The on-chip reset circuit is selected by a bit in the ECON
register. When enabled, the device generates an internal
reset as V
rises to a voltage level above 2.0V. The on-chip
CC
reset circuitry is able to detect both fast and slow rise times
on V
CC(VCC
antee an on-chip power-on-reset, V
rise time between 10 ns and 50 ms).To guar-
must start at a voltage
CC
less than the start voltage specified in the DC characteristics. Also, if V
be lowered to the start voltage before
CC
powering back up to the operating range. If this is not possible, it is recommended that external reset be used.
Under no circumstances should the RESET pin be allowed
to float. If the on-chip Power-On Reset feature is being used,
10131715
FIGURE 10. Reset Timing (Power-On Reset Enabled)
with V
Tied to RESET
CC
10131716
FIGURE 11. Reset Circuit Using Power-On Reset
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5.0 Functional Description (Continued)
5.10 OSCILLATOR CIRCUITS
There are four clock oscillator options available: Crystal
Oscillator with or without on-chip bias resistor, R/C Oscillator
with on-chip resistor and capacitor, and External Oscillator.
COP8SG Family
The oscillator feature is selected by programming the ECON
register, which is summarized in
TABLE 1. Oscillator Option
ECON4 ECON3Oscillator Option
00External Oscillator
10Crystal Oscillator without Bias Resistor
01R/C Oscillator
11Crystal Oscillator with Bias Resistor
5.10.1 Crystal Oscillator
The crystalOscillator mode can be selected by programming
ECON Bit 4 to 1. 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 can be enabled by programming ECON Bit 3 to 1 with the crystal oscillator option
selection. The value of the resistor is in the range of 0.5M to
2M (typically 1.0M).
Table 2
required for various standard crystal values. Resistor R2 is
only used when the on-chip bias resistor is disabled.
12
shows the crystal oscillator connection diagram.
TABLE 2. Crystal Oscillator Configuration,
T
= 25˚C, VCC=5V
A
R1 (kΩ)R2(MΩ)C1 (pF)C2 (pF)
01181815
01202010
0125254
5.61100100–1560.455
Table 1
.
shows the component values
Figure
CKI Freq.
(MHz)
specified duty cycle, rise and fall times, and input levels.
G7/CKO is available as a general purpose input G7 and/or
Halt control.
Figure 13
shows the external oscillator connec-
tion diagram.
5.10.3 R/C Oscillator
The R/C Oscillator mode can be selected by programming
ECON Bit 3 to 1 and ECON Bit 4 to 0. In R/C oscillation
mode, CKI is left floating, while G7/CKO is available as a
general purpose input G7 and/or HALT control. The R/C
controlled oscillator has on-chip resistor and capacitor for
maximum R/C oscillator frequency operation. The maximum
frequency is 5 MHz
±
35% for VCCbetween 4.5V to 5.5V
and temperature range of −40˚C to +85˚C. For max frequency operation, the CKI pin should be left floating. For
lower frequencies, an external capacitor should be connected between CKI and either V
or GND. Immunity of the
CC
R/C oscillator to external noise can be improved by connecting one half the external capacitance to V
and one half to
CC
GND. PC board trace length on the CKI pin should be kept
as short as possible.
as a function of external capacitance on the CKI pin.
14
shows the R/C oscillator configuration.
Table 3
shows the oscillator frequency
Figure
TABLE 3. R/C Oscillator Configuration,
−40˚C to +85˚C, V
OSC Freq. Variation of
External
Capacitor (pF)*
R/C OSC Freq
= 4.5V to 5.5V,
CC
(MHz)
±
35%
Instr. Cycle (µs)
052.0
942.5
5225.0
125110
610032 kHz312.5
* Assumes 3-5 pF board capacitance.
5.10.2 External Oscillator
The External Oscillator mode can be selected by programming ECON Bit 3 to 0 and ECON Bit 4 to 0. CKI can be
driven by an external clock signal provided it meets the
With On-Chip Bias ResistorWithout On-Chip Bias Resistor
1013171710131718
FIGURE 12. Crystal Oscillator
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5.0 Functional Description (Continued)
10131719
FIGURE 13. External Oscillator
10131720
For operation at lower than maximum R/C oscillator frequency.
COP8SG Family
PSW Register (Address X'00EF)
HCC T1PNDA T1ENAEXPNDBUSY EXEN GIE
Bit 7Bit 0
The PSW register contains the following select bits:
HCHalf Carry Flag
CCarry Flag
T1PNDA Timer T1 Interrupt Pending Flag (Autoreload RA
in mode1, T1 Underflow in Mode 2, T1Acapture
edge in mode 3)
T1ENATimer T1 Interrupt Enable for Timer Underflow
The Half-Carryflag is also affectedby all theinstructions that
affect the Carry flag. The SC (Set Carry) and R/C (Reset
Carry) instructionswill respectively setor clear boththe carry
flags. In addition to the SC and R/C instructions, ADC,
SUBC, RRC and RLC instructions affect the Carry and Half
Carry flags.
ICNTRL Register (Address X'00E8)
Reserved LPEN T0PND T0EN µWPND µWEN T1PNDB T1ENB
Bit 7Bit 0
For operation at maximum R/C oscillator frequency.
10131721
FIGURE 14. R/C Oscillator
5.11 CONTROL REGISTERS
CNTRL Register (Address X'00EE)
T1C3T1C2 T1C1T1C0 MSEL IEDGSL1SL0
Bit 7Bit 0
The Timer1 (T1) and MICROWIRE/PLUS control register
contains the following bits:
T1C3Timer T1 mode control bit
T1C2Timer T1 mode control bit
T1C1Timer T1 mode control bit
T1C0Timer T1 Start/Stop control in timer
modes 1 and 2, T1 Underflow Interrupt
Pending Flag in timer mode 3
MSELSelects G5 and G4 as MICROWIRE/PLUS
signals SK and SO respectively
IEDGExternal 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)
The ICNTRL register contains the following bits:
Reserved This bit is reserved and must be zero
LPENLPortInterruptEnable(Multi-Input
The T2CNTRL control register contains the following bits:
T2C3Timer T2 mode control bit
T2C2Timer T2 mode control bit
T2C1Timer T2 mode control bit
T2C0TimerT2Start/Stopcontrolintimer
modes 1 and 2, T2 Underflow Interrupt Pend-
ing 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)
T2ENATimer T2 Interrupt Enable for Timer Underflow
or T2A Input capture edge
T2PNDB Timer T2 Interrupt Pending Flag for T2B cap-
ture edge
T2ENBTimer T2 Interrupt Enable for Timer Underflow
or T2B Input capture edge
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5.0 Functional Description (Continued)
T3CNTRL Register (Address X'00B6)
T3C3T3C2T3C1T3C0T3PNDA T3ENA T3PNDB T3ENB
Bit 7Bit 0
COP8SG Family
The T3CNTRL control register contains the following bits:
T3C3Timer T3 mode control bit
T3C2Timer T3 mode control bit
T3C1Timer T3 mode control bit
T3C0TimerT3Start/Stopcontrolintimer
modes 1 and 2, T3 Underflow Interrupt Pending Flag in timer mode 3
T3PNDA Timer T3 Interrupt Pending Flag (Autoreload
RA in mode 1, T3 Underflow in mode 2, T3A
capture edge in mode 3)
T3ENATimer T3 Interrupt Enable for Timer Underflow
or T3A Input capture edge
T3PNDB Timer T3 Interrupt Pending Flag for T3B cap-
ture edge
T3ENBTimer T3 Interrupt Enable for Timer Underflow
or T3B Input capture edge
6.0 Timers
Each device contains a very versatile set of timers (T0, T1,
T2 and T3).Timer T1, T2 and T3 and associated autoreload/
capture registers power up containing random data.
6.1 TIMER T0 (IDLE TIMER)
Each 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. The Timer
T0 runs continuously at the fixed rate of the instruction cycle
clock, t
which is a count down timer.
The Timer T0 supports the following functions:
•
•
•
•
The IDLE Timer T0 can generate an interrupt when the
twelfth bit toggles. This toggle is latched into the T0PND
pending flag, and will occur every 2.731 ms at the maximum
clock frequency(t
interrupt from the twelfth bit of Timer T0 to be enabled or
disabled. Setting T0EN will enable the interrupt, while resetting it will disable the interrupt.
6.2 TIMER T1, TIMER T2 and TIMER T3
Each device have a set of three powerful timer/counter
blocks, T1, T2 and T3. Since T1, T2, and T3 are identical, all
comments are equally applicable to any of the three timer
blocks which will be referred to as Tx.
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 user cannot reador write tothe IDLE TimerT0,
C
Exit out of the Idle Mode (See Idle Mode description)
WATCHDOG logic (See WATCHDOG description)
Start up delay out of the HALT mode
Timing the width of the internal power-on-reset
= 0.67µs). Acontrol flagT0EN allows the
C
The control bits TxC3, TxC2, andTxC1 allow selection of the
different modes of operation.
6.2.1 Mode 1. Processor Independent PWM Mode
One of the timer’s operating modes is the Processor Independent PWM mode. In this mode, the timer generates a
“Processor Independent” PWM signal because once the
timer is setup, no more action is required from the CPU
which translates to less 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” timer 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).
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 PMW outputs are useful in controlling motors, triacs, the
intensity of displays, and in providing inputs for data acquisition and sine wave generators.
In this mode, the timer Tx counts down at a fixed rate of t
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 totoggle the TxAoutput
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.
6.2.2 Mode 2. External Event Counter Mode
This mode is quite similar to the processor independent
PWM mode described above. The main differenceis that the
timer,Tx, is clocked by the input signal from the TxA pin. The
Tx timercontrol bits, TxC3,TxC2 andTxC1 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.
.
C
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Page 23
6.0 Timers (Continued)
10131746
FIGURE 15. Timer in PWM Mode
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
Event Counter mode.
Note: The PWM outputis not available inthis mode since theTxApinis being
shows a block diagram of the timer in External
used as the counter input clock.
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
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 Txis constantly running at the fixed t
rate. The two registers, RxA and RxB, act as capture registers. Eachregister acts inconjunction with apin. The register
RxAacts in conjunction with theTxA pinand the registerRxB
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. 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. Timer T2 and T3 are identical to T1.
COP8SG Family
C
10131747
FIGURE 16. Timer in External Event Counter Mode
6.2.3 Mode 3. Input Capture Mode
Each 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
10131748
FIGURE 17. Timer in Input Capture Mode
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Page 24
6.0 Timers (Continued)
6.3 TIMER CONTROL FLAGS
The control bits and their functions are summarized below.
TxC3Timer mode control
COP8SG Family
TxC2Timer mode control
TxC1Timer mode control
TxC0Timer Start/Stop control in Modes 1 and 2 (Pro-
cessor 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
TxENATimer Interrupt Enable Flag
1 = Timer Interrupt Enabled
0 = Timer Interrupt Disabled
TxPNDB Timer Interrupt Pending Flag
TxENBTimer Interrupt Enable Flag
1 = Timer Interrupt Enabled
0 = Timer Interrupt Disabled
The timer mode control bits (TxC3, TxC2 and TxC1) are
detailed below:
ModeTxC3TxC2TxC1Description
101PWM: TxA ToggleAutoreload RAAutoreload RBt
1
100PWM: No TxA
Toggle
000External Event
2
001External Event
Counter
Counter
010Captures:Pos. TxA EdgePos. TxB Edget
TxA Pos. Edgeor Timer
TxB Pos. EdgeUnderflow
110Captures:Pos. TxANeg. TxBt
TxA Pos. EdgeEdge or TimerEdge
3
011Captures:Neg. TxANeg. TxBt
TxB Neg. EdgeUnderflow
TxA Neg. EdgeEdge or TimerEdge
TxB Neg. EdgeUnderflow
111Captures:Neg. TxANeg. TxBt
TxA Neg. EdgeEdge or TimerEdge
TxB Neg. EdgeUnderflow
Interrupt A
Source
Autoreload RAAutoreload RB
Interrupt B
Source
Timer
Counts On
C
t
C
Timer UnderflowPos. TxB EdgePos. TxA
Edge
Timer UnderflowPos. TxB EdgePos. TxA
Edge
C
C
C
C
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Page 25
7.0 Power Saving Features
Today, the proliferation of battery-operated based 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
battery-operated, consumer/industrial, and automotive applications.
Each 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 wakeup (MIWU).
Each device offers the user two power save modes of operation: HALT and IDLE. In the HALT mode, all microcontroller activities are stopped. In the IDLE mode, the on-board
oscillator circuitry and timer T0 are active but all other microcontroller activities are stopped. In either mode, all on-board
RAM, registers, I/O states, and timers (with the exception of
T0) are unaltered.
Clock Monitor, if enabled, can be active in both modes.
7.1 HALT MODE
Each devicecan be placed in the HALTmode bywriting a “1”
to the HALT flag (G7 data bit). All microcontroller activities,
including the clock and timers, are stopped. The WATCHDOG logic on the devices are disabled during the HALT
mode. However, the clock monitor circuitry, if enabled, remains active and will cause the WATCHDOG output pin
(WDOUT) to go low. If the HALT mode is used and the user
does not want to activate the WDOUT pin, the Clock Monitor
should be disabled after the devices come out of reset
(resetting the Clock Monitor control bit with the first write to
the WDSVR register). In the HALTmode, the power requirements of the devices are minimal and the applied voltage
(V
) maybe decreased toVr(Vr= 2.0V)without altering the
CC
state of the machine.
Each device supports three different ways of exiting the
HALT mode. The first method of exiting the HALT mode is
with the Multi-Input Wakeup feature on Port L. The second
method is with a low to high transition on the CKO (G7) pin.
This method precludes the use of the crystal clock configuration (since CKO becomes a dedicated output), and so may
only be used with an R/C clock configuration. The third
method of exiting the HALT mode is by pulling the RESET
pin low.
On wakeup from G7 or Port L, the devices resume execution
from the HALTpoint. On wakeup from RESET execution will
resume from location PC=0 and all RESET conditions apply.
If a crystal or ceramic resonator may be selected as the
oscillator, the Wakeup signal is not allowed to start the chip
running immediately since crystal oscillators and ceramic
resonators have a delayed start up time to reach full amplitude and frequency stability. The IDLE timer is used to
generate a fixed delay to ensure that the oscillator has
indeed stabilized before allowing instruction execution. In
this case, upon detecting a valid Wakeup signal, only the
oscillator circuitry is enabled. The IDLE timer is loaded with
a value of 256 and is clocked with the t
clock. The t
clock is derived by dividing the oscillator clock
C
instruction cycle
C
down by a factor of 9. The Schmitt trigger following the CKI
inverter on the chip ensures that the IDLE timer is clocked
only when the oscillator has a sufficiently large amplitude to
meet the Schmitt trigger specifications. This Schmitt trigger
is not part of the oscillator closed loop. The start-up time-out
from the IDLE timer enables the clock signals to be routed to
the rest of the chip.
If an R/C clock option is being used, the fixed delay is
introduced optionally. A control bit, CLKDLY, mapped as
configuration bit G7, controls whether the delay is to be
introduced or not. The delay is included if CLKDLY is set,
and excluded if CLKDLY is reset. The CLKDLY bit is cleared
on reset.
Each device has two options associated with the HALT
mode. The first option enables the HALT mode feature, while
the second option disables the HALT mode selected through
bit 0 of the ECON register. With the HALT mode enable
option, the device will enter and exit the HALT mode as
described above. With the HALT disable option, the device
cannot be placed in the HALT mode (writing a “1” to the
HALT flag will have no effect, the HALT flag will remain “0”).
The WATCHDOG detector circuit is inhibited during the
HALT mode. However, the clock monitor circuit if enabled
remains active during HALT mode in order to ensure a clock
monitor error if the device inadvertently enters the HALT
mode as a result of a runaway program or power glitch.
If the device is placed in the HALT mode, with the R/C
oscillator selected, the clock input pin (CKI) is forced to a
logic high internally. With the crystal or external oscillator the
CKI pin is TRI-STATE.
It isrecommended that the user not halt the device by merely
stopping the clock in external oscillator mode. If this method
is used, there is a possibility of greater than specified HALT
current.
If the user wishes to stop an external clock, it is recommended that the CPU be halted by setting the Halt flag first
and the clock be stopped only after the CPU has halted.
COP8SG Family
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7.0 Power Saving Features (Continued)
COP8SG Family
7.2 IDLE MODE
The device is placed in the IDLE mode by writing a “1” to the
IDLE flag (G6 data bit). In this mode, all activities, except the
associated on-board oscillator circuitry and the IDLE Timer
T0, are stopped.
As with the HALT mode, the device can be returned to
normal operation with a reset, or with a Multi-Input Wakeup
from the L Port. Alternately, the microcontroller resumes
normal operation from the IDLE mode when the twelfth bit
(representing 4.096 ms at internal clock frequency of
10 MHz, t
This toggle condition of the twelfth bit of the IDLE Timer T0 is
latched into the T0PND pending flag.
The user has the option of being interrupted with a transition
on the twelfth bit of the IDLE Timer T0. The interrupt can be
enabled or disabled via the T0EN control bit. Setting the
T0EN flag enables the interrupt and vice versa.
= 1 µs) of the IDLE Timer toggles.
C
10131725
FIGURE 18. Wakeup from HALT
The user can enter the IDLE mode with the Timer T0 interrupt enabled. In this case, when the T0PND bit gets set, the
device will first execute the TimerT0 interrupt service routine
and then return to the instruction following the “Enter Idle
Mode” instruction.
Alternatively, the user can enter the IDLE mode with the
IDLE TimerT0 interrupt disabled. In this case, the device will
resume normal operation with the instruction immediately
following the “Enter IDLE Mode” instruction.
Note: It is necessary to program two NOP instructions following both the set
HALT mode and set IDLE mode instructions. These NOP instructions
are necessary to allow clock resynchronization following the HALT or
IDLE modes.
FIGURE 19. Wakeup from IDLE
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10131726
Page 27
7.0 Power Saving Features (Continued)
7.3 MULTI-INPUT WAKEUP
The Multi-Input Wakeup feature is used to return (wakeup)
the device from either the HALT or IDLE modes. Alternately
Multi-Input Wakeup/Interrupt feature may also be used to
generate up to 8 edge selectable external interrupts.
Figure 20
The Multi-Input Wakeup 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 Wakeup 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
Wakeup 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 thisprocedure. Suppose we
wish tochange the edgeselect from positive(low going high)
shows the Multi-Input Wakeup logic.
COP8SG Family
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:
If the L port bits have been used as outputs and then
changed toinputs with Multi-InputWakeup/Interrupt, a safety
procedure should also be followed to avoid wakeup 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
be set or reset for the desired edge selects, followed by the
associated WKPND bits being cleared.
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 Wakeup 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 wakeup conditions, the device
will not enter the HALT mode if any Wakeup bit is both
enabled and pending. Consequently, the user must clear the
pending flags before attempting to enter the HALT mode.
WKEN and WKEDG are all read/write registers, and are
cleared at reset. WKPND register contains random value
after reset.
FIGURE 20. Multi-Input Wake Up Logic
10131727
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Page 28
8.0 USART
Each device contains a full-duplex software programmable
USART. The USART (
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
COP8SG Family
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 and parity errors while the USART is receiving.
Figure 21
) consists of a transmit shift
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 ofan internal orexternal 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.
FIGURE 21. USART Block Diagram
8.1 USART CONTROL AND STATUS REGISTERS
The operation of the USART is programmed through three
registers: ENU, ENUR and ENUI.
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10131739
8.2 DESCRIPTION OF USART REGISTER BITS
ENU-USART Control and Status Register (Address at 0BA)
PEN PSEL1 XBIT9/ CHL1 CHL0ERRRBFL TBMT
PSEL0
Bit 7Bit 0
Page 29
8.0 USART (Continued)
PEN: This bit enables/disables Parity (7- and 8-bit modes
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.
mitter output internally looped back
to receiver input. Nine bit framing
format is used.
ERR: This bit is a global USART error flag which gets set if
any or a combination of the errors (DOE, FE, PE) occur.
Read only; it cannot be written by software, cleared on reset.
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.
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)
DOEFEPEReserved RBIT9 ATTN XMTG RCVG
(Note 16)
Bit 7Bit 0
Note 16: Bit is reserved for future use. User must set to zero.
DOE: Flags a Data Overrun Error. Read only, cleared on
read, cleared on reset.
DOE = 0Indicates no Data Overrun Error has been de-
tected since the last time the ENUR register
was read.
DOE = 1Indicates the occurrence of a Data Overrun
Error.
FE: Flags a Framing Error. Read only, cleared on read,
cleared on reset.
FE = 0Indicates no Framing Error has been detected
since the last time the ENUR register was read.
FE = 1Indicates the occurrence of a Framing Error.
PE: Flags a Parity Error. Read only, cleared on read, cleared
on reset.
PE = 0Indicates no Parity Error has been detected since
COP8SG Family
the last time the ENUR register was read.
PE = 1Indicates the occurrence of a Parity Error.
SPARE: Reserved for future use. Read/Write, cleared on
reset.
RBIT9: Contains the ninth data bit received when the US-
ART is operating with nine data bits per frame. Read only,
cleared on reset.
ATTN: ATTENTION Mode is enabled while this bit is set.
This bitis cleared automatically onreceiving a character with
data bit nine set. Read/Write, cleared on reset.
XMTG: This bit is set to indicate that the USART is transmitting. Itgets reset at the end of the last frame (endof last Stop
bit). Read only, cleared on reset.
RCVG: This bit is set high whenever a framing error occurs
and goes low when RDX goes high. Read only, cleared on
reset.
ENUI-USART Interrupt and Clock Source Register
(Address at 0BC)
STP2 STP78 ETDX SSEL XRCLK XTCLKERIETI
Bit 7Bit 0
STP2: This bit programs the number of Stop bits to be
transmitted. Read/Write, cleared on reset.
STP2 = 0One Stop bit transmitted.
STP2 = 1Two Stop bits transmitted.
STP78: This bit is set to program the last Stop bit to be 7/8th
of a bit in length. Read/Write, cleared on reset.
ETDX: TDX (USART Transmit Pin) is the alternate function
assigned to Port L pin L2; it is selected by setting ETDX bit.
To simulate line break generation, software should reset
ETDX bit and output logic zero to TDX pin through Port L
data and configuration registers. Read/Write, cleared on
reset.
SSEL: USART mode select. Read/Write, cleared on reset.
SSEL = 0Asynchronous Mode.
SSEL = 1Synchronous Mode.
XRCLK: This bit selects the clock source for the receiver
section. Read/Write, cleared on reset.
XRCLK = 0The clock source is selected through the
PSR and BAUD registers.
XRCLK = 1Signal 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 = 0The clock source is selected through the PSR
and BAUD registers.
XTCLK = 1Signal 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 = 0Interrupt from the receiver is disabled.
ERI = 1Interrupt from the receiver is enabled.
ETI: This bit enables/disables interrupt from the transmitter
section. Read/Write, cleared on reset.
ETI = 0Interrupt from the transmitter is disabled.
ETI = 1Interrupt from the transmitter is enabled.
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8.0 USART (Continued)
8.3 Associated I/O Pins
Data is transmitted on theTDX 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.
COP8SG Family
RDX is an inherent function of Port L pin L3, requiring no
setup.
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.
8.4 USART Operation
The USART has two modes of operation: asynchronous
mode and synchronous mode.
8.4.1 ASYNCHRONOUS MODE
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 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 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 validStart bit, and the remaining bits in the character frame are each sampled a single
time, at the mid-bit position. 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 occurs and goes low once RDX goes
high. TBMT, XMTG, RBFL and RCVG are read only bits.
8.4.2 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 anexternal clock input is selected at the CKX pin, data
transmit and receive are performed synchronously with this
clock through TDX/RDX pins.
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.
8.5 FRAMING FORMATS
The USART supports several serial framing formats (
22
). The format is selected using control bits in the ENU,
ENUR and ENUI registers.
The first format (1, 1a, 1b, 1c) for data transmission (CHL0 =
1, CHL1 = 0) consists of Start bit, seven Data bits (excluding
parity) and 7/8, one or two Stop bits. In applications using
parity, the parity bit is generated and verified by hardware.
The second format (CHL0 = 0, CHL1 = 0) consists of one
Start bit, eight Data bits (excluding parity) and 7/8, 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 7/8, 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.
For any of the above framing formats, the last Stop bit can
be programmed to be 7/8th of a bit in length. If two Stop bits
are selected and the 7/8th bit is set (selected), the second
Stop bit will be 7/8th of a bit in length.
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 andthe bit is PSEL0 used in conjunctionwith 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 oneStop bit ina frame, regardlessof 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.
Figure
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8.0 USART (Continued)
COP8SG Family
FIGURE 22. Framing Formats
8.6 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).
8.7 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
10131740
source selected in the PSR and BAUD registers. Internally,
the basic baud clock is created from the oscillator frequency
through a two-stage divider chain consisting of a 1–16 (increments of 0.5) prescaler and an 11-bit binary counter.
(
Figure 23
read/write registers shown in
Baud Rate Divisor spills over into the Prescaler Select Register (PSR). PSR is cleared upon reset.
As shown in
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
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 outputis then used todrive the software programmable
baud ratecounter 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 (
). The divide factors are specified through two
Figure 24
Table 5
, a Prescaler Factor of 0 corresponds to
. Note that the 11-bit
Table 5
. There are many
Table 4
). Other baud
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8.0 USART (Continued)
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.
asynchronous mode the baud rate could be as high as 987.5k.
Table4
assume a prescaler output of 1.8432 MHz. In the
TABLE 5. Prescaler Factors
PrescalerPrescaler
SelectFactor
00000NO CLOCK
000011
000101.5
000112
PrescalerPrescaler
SelectFactor
001002.5
001013
001103.5
001114
010004.5
010015
010105.5
010116
011006.5
011017
011107.5
011118
100008.5
100019
100109.5
1001110
1010010.5
1010111
1011011.5
1011112
1100012.5
1100113
1101013.5
1101114
1110014.5
1110115
1111015.5
1111116
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8.0 USART (Continued)
As an example, considering Asynchronous Mode and a CKI
clock of 4.608 MHz, the prescaler factor selected is:
4.608/1.8432 = 2.5
The 2.5 entry is available in
prescaler output is then used with proper Baud Rate Divisor
(
Table 4
) to obtain different baud rates. For a baud rate of
19200 e.g., the entry in
N−1=5(N−1isthevalue from
N=6(NistheBaud 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/(16xNxP)
Where:
BR is the Baud Rate
Fc is the CKI frequency
N is the Baud Rate Divisor (
P is the Prescaler Divide Factor selected by the value in the
Prescaler Select Register (
Note: In the Synchronous Mode, the divisor 16 is replaced by two.
Example:
Asynchronous Mode:
Crystal Frequency=5MHz
Desired baud rate = 9600
Using the above equationNxPcanbecalculated first.
NxP=(5x10
Now 32.552 is divided by each Prescaler Factor (
obtain a value closest to an integer. This factor happens to
be 6.5 (P = 6.5).
N = 32.552/6.5 = 5.008 (N = 5)
The programmed value (from
Using the above values calculated for N and P:
BR=(5x10
% error = (9615.385 − 9600)/9600 x 100 = 0.16%
8.8 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 Wakeup scheme
provided on the device.
Before entering the HALT or IDLE modes the user program
must select the Wakeup source to be on the RDX pin. This
selection is done by setting bit 3 of WKEN (Wakeup Enable)
register.The Wakeup 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
Wakeup signal will not start the chip running immediately
6
)/(16x5x6.5) = 9615.384
Table 5
Table 4
. The 1.8432 MHz
is 5.
Table 4
Table 4
).
Table 5
)
6
)/(16 x 9600) = 32.552
Table 4
) should be 4 (N − 1).
)
Table 5
)to
because of the finite start up time requirement of the crystal
oscillator.The idle timer (T0) generates a fixed (256 t
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.
8.9 Diagnostic
Bits CHARL0 and CHARL1 in the ENU register provide a
loopback feature for diagnostic testing of the USART. When
these bits are set to one, the following occur: 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 7/8, one or two Stop
bits. Parity is not generated or verified in this mode.
8.10 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 7/8, 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 interruptsare enabled. The ATTN bit isalso 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.
) delay
c
9.0 Comparators
The device contains two differential comparators, each with
a pair of inputs (positive and negative) and an output. Ports
F1–F3 and F4–F6 are used for the comparators. The following is the Port F assignment:
A Comparator Select Register (CMPSL) is used to enable
the comparators, read the outputs of the comparators internally, and enable the outputs of the comparators to the pins.
COP8SG Family
Two control bits (enable and output enable) and one result
bit are associated with each comparator. The comparator
result bits (CMP1RD and CMP2RD) are read only bits which
will read as zero if the associated comparator is not enabled.
The Comparator Select Register is cleared with reset, resulting in the comparators being disabled. The comparators
should also be disabled before entering either the HALT or
IDLE modes in order to save power. The configuration of the
CMPSL register is as follows:
CMPSL REGISTER (ADDRESS X’00B7)
The CMPSL register contains the following bits:
Reserved These bits are reserved and must be zero
CMP20E Selects pin I6 as comparator 2 output provided
that CMP2EN is set to enable the comparator
CMP2RD Comparator 2 result (this is a read only bit, which
will read as 0 if the comparator is not enabled)
CMP2EN Enable comparator 2
CMP10E Selects pin I3 as comparator 1 output provided
that CMPIEN is set to enable the comparator
CMP1RD Comparator 1 result (this is a read only bit, which
will read as 0 if the comparator is not enabled)
CMP1EN Enable comparator 1
Note that the two unused bits of CMPSL may be used as
software flags.
Note: If the user attempts to use the comparator output
immediately after enabling the comparator, an incorrect
value maybe read.At least one instruction cycle should pass
between these operations. The use of a direct addressing
mode instruction for either of these two operations will guarantee this delay in the software.
Note: For compatibility with existing code and with existing Mask ROMMed
devices the bits of the CMPSL register will take precedence over the
associated Port F configuration and data output bits.
10.0 Interrupts
10.1 INTRODUCTION
Each device supports thirteen vectored interrupts. Interrupt
sources include Timer 0, Timer 1, Timer 2, Timer 3, Port L
Wakeup, Software Trap, MICROWIRE/PLUS, 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.
The Software trap has the highest priority while the default
VIS has the lowest priority.
Each of the 13 maskable inputs has a fixed arbitration ranking and vector.
Figure 25
shows the Interrupt Block Diagram.
FIGURE 25. Interrupt Block Diagram
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10131728
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10.0 Interrupts (Continued)
10.2 MASKABLE INTERRUPTS
All interrupts other than the Software Trap are maskable.
Each maskable interrupt has an associated enable bit and
pending flagbit. The pendingbit is setto 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.
Amaskable 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 highest
priority 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 cannottrigger an interruptuntil the programenables 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
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 untilthe start ofthe next normallyexecuted instruction
is to be skipped, the skip is performed before the pending
interrupt is acknowledged.
At the start of interrupt acknowledgment, the following actions occur:
1. The GIEbit 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 routinemay set the GIE bit to 1by 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.
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, ifthe 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 sets the GIE bit back to 1, pops
the addressstored on the stack, and restores thataddress 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.
10.3 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.
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.
The vectortable may beas long as32 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
rank 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 6
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 filledby the user withthe memory
locations of the specific interrupt service routines. For ex-
COP8SG Family
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10.0 Interrupts (Continued)
ample, 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.
COP8SG Family
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.
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 pro-
gram context (A, B, X, etc.) and executing the RETI instruction, an interrupt service routine can beterminated 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 (t
more, (50µs at 10 MHz oscillator) of latency for pending
interrupts with a penalty of fewer than ten instruction cycles
if no further interrupts are pending.
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 ofan 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.
TABLE 6. Interrupt Vector Table
Vector Address (Note 17)
(Hi-Low Byte)
c
), or
Note 17: 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.
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10.0 Interrupts (Continued)
10.3.1 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 the only active
interrupt is software trap, 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 nowpointed to the 1st instruction
of the service routine of the active interrupt with the highest
arbitration ranking.
Figure 26
instruction.
tion.
The non-maskable interrupt pending flag is cleared by the
RPND (Reset Non-Maskable Pending Bit) instruction (under
certain conditions) and upon RESET.
illustrates the different steps performed by the VIS
Figure 27
shows a flowchart for the VIS instruc-
COP8SG Family
FIGURE 26. VIS Operation
10131729
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10.0 Interrupts (Continued)
COP8SG Family
FIGURE 27. VIS Flowchart
10131730
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10.0 Interrupts (Continued)
Programming Example: External Interrupt
PSW=00EF
CNTRL=00EE
RBIT0,PORTGC
RBIT0,PORTGD; G0 pin configured Hi-Z
SBITIEDG, CNTRL; Ext interrupt polarity; falling edge
SBITEXEN, PSW; Enable the external interrupt
SBITGIE, PSW; Set the GIE bit
WAIT:JPWAIT; Wait for external interrupt
.
.
.
.=0FF; The interrupt causes a
VIS; branch to address 0FF
; The VIS causes a branch to
;interrupt vector table
.
.
.
.=01FA; Vector table (within 256 byte
.ADDRW SERVICE; of VIS inst.) containing the ext
; interrupt service routine
.
.
INT_EXIT:
RETI
.
.
SERVICE:RBITEXPND, PSW; Interrupt Service Routine
; Reset ext interrupt pend. bit
.
.
.
JPINT_EXIT; Return, set the GIE bit
COP8SG Family
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10.0 Interrupts (Continued)
10.4 NON-MASKABLE INTERRUPT
10.4.1 Pending Flag
There is a pending flag bit associatedwith the non-maskable
COP8SG Family
interrupt, called STPND. This pending flag is not memorymapped 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.
10.4.2 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 available program memory space, the nonexistent or unused memory location returns zeroes 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, if this lastlocation in
program memory is unprogrammed or unavailable, 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.
The Software Trap has the highest priority of all interrupts.
When aSoftware Trapoccurs, 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 Trapservice 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
reinitialize the stack pointer and perform a recovery procedure that restarts 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
STPND flag will have the wrong state. This will allow
maskable interruptsto be acknowledged during the servicing
of thefirst Software Trap. To avoidproblems such asthis, 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
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.
10.5 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.
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
HALTor IDLE modes, the user can elect to exit the HALTor
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 HALTor 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 wakeup information.)
10.6 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 restart 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 routiness if the time
between interruptsis short. Inthis case theRETI instruction would only be executed when the default VIS routine is reached.
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11.0 WATCHDOG/Clock Monitor
Each device contains a user selectable WATCHDOG and
clock monitor. The following section is applicable only if
WATCHDOG feature has been selected in the ECON 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 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 ClockMonitor is usedto detect theabsence of a clock or
a very slow clock below a specified rate on the CKI pin.
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 7
The lower limit of the service window is fixed at 2048 instruction cycles. Bits 7 and 6 of the WDSVR register allow the
user to pick an upper limit of the service window.
Table 8
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.
shows the WDSVR register.
TABLE 7. WATCHDOG Service Register (WDSVR)
Window
Select
Key Data
Clock
Monitor
XX01100Y
76543210
shows the four possible combinations of lower and
TABLE 8. WATCHDOG Service Window Select
WDSVR WDSVRClockService Window
Bit 7Bit 6Monitor(Lower-Upper Limits)
00x2048–8k t
01x2048–16k t
10x2048–32k t
11x2048–64k t
The WATCHDOG is enabled by bit 2 of the ECON register.
When this ECON 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 and the key data (bits 7
through 1) in the WDSVR Register.
Table 9
shows the se-
quence 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.
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 andmust be externally connected to the RESETpin or to
some otherexternal logic which handles WATCHDOG event.
The WDOUTpin has a weak pullup in the inactive state. This
pull-up is sufficient to serve as the connection to V
for
CC
systems which use the internal Power On Reset. Upon
triggering the WATCHDOG, the logic will pull the WDOUT
(G1) pin low for an additional 16 t
–32tCcycles after the
C
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.
AWATCHDOGservice while theWDOUT 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
t
–32 tCclock cycles. The Clock Monitor generates a con-
C
tinual 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/t
10 kHz—No clock rejection.
C
<
1/t
10 Hz—Guaranteed clock rejection.
C
COP8SG Family
11.1 CLOCK MONITOR
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/t
) is greater or equal to 10 kHz. This equates to a
C
clock input rate on CKI of greater or equal to 100 kHz.
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Page 42
11.0 WATCHDOG/Clock Monitor (Continued)
TABLE 9. WATCHDOG Service Actions
KeyWindowClockAction
DataDataMonitor
COP8SG Family
MatchMatchMatchValid Service: Restart Service Window
The following salient points regarding the WATCHDOG and
CLOCK MONITOR should be noted:
Both the WATCHDOG and CLOCK MONITOR detector
•
circuits are inhibited during RESET.
Following RESET, the WATCHDOG and CLOCK MONI-
•
TOR are both enabled, with the WATCHDOG having the
maximum service window selected.
The WATCHDOG service window and CLOCK MONI-
•
TOR 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).
With the single-pin R/C oscillator option selected and the
•
CLKDLY bit reset, the WATCHDOG service window will
resume following HALT mode from where it left off before
entering the HALT mode.
With the crystal oscillator option selected, or with the
•
single-pin R/C oscillator option selected and the CLKDLY
bit set, 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 instruction cycles 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 isset whenever the twelfthbit of the
IDLE countertoggles (every 4096 instruction cycles). The
user is responsible for resetting the T0PND flag.
A hardware WATCHDOG service occurs just as the de-
•
vice exits the IDLE mode. Consequently, the WATCHDOG should not be serviced for at least 2048 instruction
cycles 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 thatthis initial
WATCHDOG service may be programmed within the initial 2048 instruction cycles without causing a WATCHDOG error.
11.4 DETECTION OF ILLEGAL CONDITIONS
The device can detect various illegal conditions resulting
from coding errors, transient noise, power supply voltage
drops, runaway programs, etc.
Reading of undefined ROM gets zeroes. The opcode for
software interrupt is 00. If the program fetches instructions
from undefined ROM, this will force asoftware 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 orPOP. 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. It
is recommended that the user either leave this location
unprogrammed or place an INTR instruction (all 0’s) in this
location to generate a software interrupt signaling an illegal
condition.
Thus, the chip can detect the following illegal conditions:
1. Executing from undefined ROM.
2. Over “POP”ing the stack by having more returns than
calls.
When the software interrupt occurs, the user can re-initialize
the stackpointer and doa recovery procedurebefore 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.
12.0 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).
shows a block diagram of the MICROWIRE/PLUS logic.
The shiftclock can be selected from either aninternal source
or an external source. Operating the MICROWIRE/PLUS
Figure 28
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Page 43
12.0 MICROWIRE/PLUS (Continued)
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.
different clock rates that may be selected.
TABLE 10. MICROWIRE/PLUS
Master Mode Clock Select
SL1SL0SK Period
002xt
014xt
1x8xt
Where tCis the instruction cycle clock
12.1 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
Table 10
details the
C
C
C
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 28
shows how
two microcontroller devices and several peripherals may be
interconnected usingthe MICROWIRE/PLUS arrangements.
WARNING
The SIO register should only be loaded when the SK clock is
in theidle 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.
12.1.1 MICROWIRE/PLUS Master Mode Operation
In the MICROWIRE/PLUS Master mode of operation the
shift clock (SK) is generated internally. The MICROWIRE
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 11
summarizes the bit
settings required for Master mode of operation.
COP8SG Family
FIGURE 28. MICROWIRE/PLUS Application
10131732
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12.0 MICROWIRE/PLUS (Continued)
12.1.2 MICROWIRE/PLUS Slave Mode Operation
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
COP8SG Family
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.
the Slave mode of operation.
Table 11
summarizes the settings required to enter
TABLE 11. MICROWIRE/PLUS Mode Settings
This table assumes that the control flag MSEL is set.
G4 (SO)G5 (SK)G4G5Operation
Config. BitConfig. BitFun.Fun.
11SOInt.MICROWIRE/PLUS
SK Master
01TRI-Int.MICROWIRE/PLUS
STATESK Master
10SOExt. MICROWIRE/PLUS
SK Slave
00TRI-Ext. MICROWIRE/PLUS
STATESK Slave
TABLE 12. MICROWIRE/PLUS Shift Clock Polarity and Sample/Shift Phase
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.
12.1.3 Alternate SK Phase Operation and SK Idle P
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
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. Resetting SKSEL
causes the MICROWIRE/PLUS logic to be clocked from the
normal SK signal. Setting the SKSEL flag selects the alternate SK clock. The SKSEL is mapped into the G6 configuration bit. The SKSEL flag will power up in the reset condition, selecting the normal SK signal.
SO Clocked Out On:SI Sampled On:SK Idle
Phase
FIGURE 29. MICROWIRE/PLUS SPI Mode Interface Timing, Normal SK Mode, SK Idle Phase being Low
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10131733
Page 45
12.0 MICROWIRE/PLUS (Continued)
FIGURE 30. MICROWIRE/PLUS SPI Mode Interface Timing, Alternate SK Mode, SK Idle Phase being Low
COP8SG Family
10131734
10131735
FIGURE 31. MICROWIRE/PLUS SPI Mode Interface Timing, Normal SK Mode, SK Idle Phase being High
10131731
FIGURE 32. MICROWIRE/PLUS SPI Mode Interface Timing, Alternate SK Mode, SK Idle Phase being High
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Page 46
13.0 Memory Map
All RAM, ports and registers (except A and PC) are mapped
into data memory address space.
AddressContents
S/ADD REG
COP8SG Family
0000 to 006FOn-Chip RAM bytes (112 bytes)
0070 to 007FUnused RAM Address Space (Reads As
All Ones)
xx80 to xx93Unused RAM Address Space (Reads
Undefined Data)
xx94Port F data register, PORTFD
xx95Port F configuration register, PORTFC
xx96Port F input pins (read only), PORTFP
xx97 to xxAFUnused address space (Reads Undefined
Data)
xxB0Timer T3 Lower Byte
xxB1Timer T3 Upper Byte
xxB2Timer T3 Autoload Register T3RA Lower
Byte
xxB3Timer T3 Autoload Register T3RA Upper
Byte
xxB4Timer T3 Autoload Register T3RB Lower
Byte
xxB5Timer T3 Autoload Register T3RB Upper
Byte
xxB6Timer T3 Control Register
xxB7Comparator Select Register (Reg:CMPSL)
xxB8UART Transmit Buffer (Reg:TBUF)
xxB9UART Receive Buffer (Reg:RBUF)
xxBAUART Control and Status Register
(Reg:ENU)
xxBBUART Receive Control and Status
Register (Reg:ENUR)
xxBCUART Interrupt and Clock Source Register
Byte
xxC6Timer T2 Control Register
xxC7WATCHDOG Service Register
(Reg:WDSVR)
xxC8MIWU Edge Select Register
(Reg:WKEDG)
AddressContents
S/ADD REG
xxC9MIWU Enable Register (Reg:WKEN)
xxCAMIWU Pending Register (Reg:WKPND)
xxCB to xxCF Reserved
xxD0Port L Data Register
xxD1Port L Configuration Register
xxD2Port L Input Pins (Read Only)
xxD3Reserved for Port L
xxD4Port G Data Register
xxD5Port G Configuration Register
xxD6Port G Input Pins (Read Only)
xxD7Port I Input Pins (Read Only) (Actually
reads Port F input pins)
xxD8Port C Data Register
xxD9Port C Configuration Register
xxDAPort C Input Pins (Read Only)
xxDBReserved for Port C
xxDCPort D
xxDD to xxDF Reserved for Port D
xxE0 to xxE5Reserved for EE Control Registers
xxE6Timer T1 Autoload Register T1RB Lower
Byte
xxEECNTRL Control Register
xxEFPSW Register
xxF0 to FBOn-Chip RAM Mapped as Registers
xxFCX Register
xxFDSP Register
xxFEB Register
xxFFS Register
0100–017FOn-Chip 128 RAM Bytes
0200–027FOn-Chip 128 RAM Bytes (Reads as
undefined data on COP8SGE)
0300–037FOn-Chip 128 RAM Bytes (Reads as
undefined data on COP8SGE)
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.
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14.0 Instruction Set
14.1 INTRODUCTION
This section defines the instruction set of the COP8 Family
members. It contains information about the instruction set
features, addressing modes and types.
14.2 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 in-
•
structions 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 opti-
•
mized 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.
14.3 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 writing) data. Transfer-of-control addressing modes are used in
conjunction with jump instructions to control the execution
sequence of the software program.
14.3.1 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 beused is contained inthe 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
•
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 asa 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
Reg/DataContentsContents
MemoryBeforeAfter
AccumulatorXX HexA6 Hex
Memory LocationA6 HexA6 Hex
0005 Hex
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/DataContentsContents
MemoryBeforeAfter
Accumulator01 Hex87 Hex
Memory Location87 Hex01 Hex
0005 Hex
B Pointer05 Hex05 Hex
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
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/DataContentsContents
MemoryBeforeAfter
Accumulator03 Hex62 Hex
Memory Location62 Hex03 Hex
0005 Hex
B Pointer05 Hex06 Hex
COP8SG Family
Intermediate. The data for the operation follows the instruc-
tion opcode in program memory. In assembly language, the
number sign character (
#
) indicates an immediate operand.
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Page 48
14.0 Instruction Set (Continued)
Example: Load Accumulator Immediate
#
05
LD A,
Reg/DataContentsContents
COP8SG Family
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
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
14.3.2 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.
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:
Jump Relative
•
Jump Absolute
•
Jump Absolute Long
•
MemoryBeforeAfter
AccumulatorXX Hex05 Hex
#
LD B,
7
Reg/DataContentsContents
MemoryBeforeAfter
B Pointer12 Hex07 Hex
LAID
Reg/DataContentsContents
MemoryBeforeAfter
PCU04 Hex04 Hex
PCL35 Hex36 Hex
Accumulator1F Hex25 Hex
Memory Location25 Hex25 Hex
041F Hex
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.AJP+1 instruction is notallowed.
The programmer should use a NOP instead.
Example: Jump Relative
JP 0A
RegContentsContents
BeforeAfter
PCU02 Hex02 Hex
PCL05 Hex0F Hex
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 4 kbyte address space as the current
instruction.
(This restriction is relevant only in devices using more than
one 4 kbyte program memory space.)
Example: Jump Absolute
JMP 0125
RegContentsContents
BeforeAfter
PCU0C Hex01 Hex
PCL77 Hex25 Hex
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
Reg/ContentsContents
MemoryBeforeAfter
PCU42 Hex36 Hex
PCL36 Hex25 Hex
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
JID
Reg/ContentsContents
MemoryBeforeAfter
PCU01 Hex01 Hex
PCLC4 Hex32 Hex
Accumulator26 Hex26 Hex
Memory
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14.0 Instruction Set (Continued)
Reg/ContentsContents
MemoryBeforeAfter
Location32 Hex32 Hex
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.
14.4 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.
14.4.1 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 (SUB)
Subtract with Carry (SUBC)
Increment (INC)
Decrement (DEC)
Decimal Correct (DCOR)
Clear Accumulator (CLR)
Set Carry (SC)
Reset Carry (RC)
14.4.2 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)
Jump to Subroutine Long (JSRL)
Return from Subroutine (RET)
Return from Subroutine and Skip (RETSK)
Return from Interrupt (RETI)
Software Trap Interrupt (INTR)
Vector Interrupt Select (VIS)
COP8SG Family
14.4.3 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.
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 exclusiveORing
the Accumulator with FF Hex.
Logical AND (AND)
Logical OR (OR)
Exclusive OR (XOR)
14.4.5 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)
14.4.6 Stack Control Instructions
Push Data onto Stack (PUSH)
Pop Data off of Stack (POP)
14.4.7 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)
14.4.8 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)
14.4.9 No-Operation Instruction
The no-operation instruction does nothing, except to occupy
space in the program memory and time in execution.
No-Operation (NOP)
Note: The VIS is a special case ofthe Indirect Transferof 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.
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Page 50
14.0 Instruction Set (Continued)
14.5 REGISTER AND SYMBOL DEFINITION
The following abbreviations represent the nomenclature
used in the instruction description and the COP8
cross-assembler.
COP8SG Family
Registers
A8-Bit Accumulator Register
B8-Bit Address Register
X8-Bit Address Register
SP8-Bit Stack Pointer Register
PC15-Bit Program Counter Register
PUUpper 7 Bits of PC
PLLower 8 Bits of PC
C1 Bit of PSW Register for Carry
HC1 Bit of PSW Register for Half Carry
GIE1 Bit of PSW Register for Global Interrupt
Enable
14.6 INSTRUCTION SET SUMMARY
ADDA,MemlADDA←A + Meml
ADCA,MemlADD with CarryA←A+Meml+C,C←Carry,
SUBCA,MemlSubtract with CarryA←A−MemI+C,C←Carry,
ANDA,MemlLogical ANDA←A and Meml
ANDSZA,ImmLogical AND Immed., Skip if ZeroSkip next if (A and Imm) = 0
ORA,MemlLogical ORA←A or Meml
XORA,MemlLogical EXclusive ORA←A xor Meml
IFEQMD,ImmIF EQualCompare MD and Imm, Do next if MD = Imm
IFEQA,MemlIF EQualCompare A and Meml, Do next if A = Meml
IFNEA,MemlIF Not EqualCompare A and Meml, Do next if A
IFGTA,MemlIF Greater ThanCompare A and Meml, Do next if A
IFBNE
DRSZRegDecrement Reg., Skip if ZeroReg←Reg − 1, Skip if Reg = 0
SBIT
RBIT
IFBIT
RPNDReset PeNDing FlagReset Software Interrupt Pending Flag
XA,MemEXchange A with MemoryA
XA,[X]EXchange A with Memory [X]A
LDA,MemlLoaD A with MemoryA←Meml
LDA,[X]LoaD A with Memory [X]A←[X]
LDB,ImmLoaD B with Immed.B←Imm
LDMem,ImmLoaD Memory Immed.Mem←Imm
LDReg,ImmLoaD Register Memory Immed.Reg←Imm
XA,[B
XA,[X
LDA, [B
LDA, [X
LD[B
CLRACLeaR AA←0
#
#
,MemSet BIT1 to bit, Mem (bit = 0 to 7 immediate)
#
,MemReset BIT0 to bit, Mem
#
,MemIF BITIf bit#, A or Mem is true do next instruction
±
±
±
±
±
],ImmLoaD Memory [B] Immed.[B]←Imm, (B←B±1)
If B Not EqualDo next if lower 4 bits of B≠Imm
]EXchange A with Memory [B]A↔[B], (B←B±1)
]EXchange A with Memory [X]A↔[X], (X←X±1)
]LoaDA with Memory [B]A←[B], (B←B±1)
]LoaDA with Memory [X]A←[X], (X←X±1)
[B]Memory Indirectly Addressed by B Register
[X]Memory Indirectly Addressed by X Register
MDDirect Addressed Memory
MemDirectAddressed Memory or [B]
MemlDirect Addressed Memory or [B] or
Immediate Data
Imm8-Bit Immediate Data
RegRegister Memory: Addresses F0 to FF
(Includes B, X and SP)
BitBit Number (0 to 7)
←
↔
HC←Half Carry
HC←Half Carry
↔
↔
Mem
[X]
Loaded with
Exchanged with
Registers
Symbols
≠
>
Meml
Meml
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14.0 Instruction Set (Continued)
INCAINCrement AA←A+1
DECADECrement AA←A−1
LAIDLoad A InDirect from ROMA←ROM (PU,A)
DCORADecimal CORrect AA←BCD correction of A (follows ADC, SUBC)
RRCARotate A Right thru CC→A7→…→A0→C
RLCARotate A Left thru CC←A7←…←A0←C, HC←A0
SWAPASWAP nibbles of AA7…A4
SCSet CC←1, HC←1
RCReset CC←0, HC←0
IFCIF CIF C is true, do next instruction
IFNCIF Not CIf C is not true, do next instruction
POPAPOP the stack into ASP←SP + 1, A←[SP]
PUSHAPUSH A onto the stack[SP]←A, SP←SP − 1
VISVector to Interrupt Service RoutinePU←[VU], PL←[VL]
JMPLAddr.Jump absolute LongPC←ii (ii = 15 bits, 0 to 32k)
JMPAddr.Jump absolutePC9…0←i (i = 12 bits)
JPDisp.Jump relative shortPC←PC+r(ris−31to+32, except 1)
JSRLAddr.Jump SubRoutine Long[SP]←PL, [SP−1]←PU,SP−2, PC←ii
JSRAddr.Jump SubRoutine[SP]←PL, [SP−1]←PU,SP−2, PC9…0←i
JIDJump InDirectPL←ROM (PU,A)
RETRETurn from subroutineSP + 2, PL←[SP], PU←[SP−1]
RETSKRETurn and SKipSP + 2, PL←[SP],PU←[SP−1],
RETIRETurn from InterruptSP + 2, PL←[SP],PU←[SP−1],GIE←1
INTRGenerate an Interrupt[SP]←PL, [SP−1]←PU, SP−2, PC←0FF
NOPNo OPerationPC←PC+1
↔
A3…A0
skip next instruction
COP8SG Family
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Page 52
14.0 Instruction Set (Continued)
14.7 INSTRUCTION EXECUTION TIME
Most instructions are single byte (with immediate addressing
mode instructions taking two bytes).
Most single byte instructions take one cycle time to execute.
COP8SG Family
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 followingtable shows thenumber of bytesand cycles for
each instruction in the format of byte/cycle.
X A, (Note 18)1/11/32/31/21/3
LD A, (Note 18)1/11/32/32/21/21/3
LD B, Imm1/1(If B
LD B, Imm2/2(If B
LD Mem, Imm2/23/32/2
LD Reg, Imm2/3
IFEQ MD, Imm3/3
Note 18: =>Memory location addressed by B or X or directly.
Memory Transfer Instructions
<
16)
>
15)
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Page 53
COP8SG Family
Lower Nibble
14.8 OPCODE TABLE
Upper Nibble
JP+17 INTR0
JMP
x000–x0FF
x000–x0FF
IFBNE 0JSR
LD
B,#0F
A, #i
ANDSZ
0,[B]
IFBIT
ADC
A,[B]
JP+18 JP+21
JP+19 JP+32
JMP
JMP
x100–x1FF
x100–x1FF
IFBNE 1JSR
IFBNE 2JSR
B,#0E
*LD
*LD
1,[B]
IFBIT
IFBIT
A,[B]
IFEQ
SUBC
JP+20 JP+43
JMP
x200–x2FF
x200–x2FF
IFBNE 3JSR
B,#0D
*LD
2,[B]
IFBIT
A,[B]
IFGT
JP+21 JP+54
JMP
x300–x3FF
x300–x3FF
IFBNE 4JSR
B,#0C
CLRALD
3,[B]
IFBIT
ADD
A,[B]
JP+22 JP+65
JMP
x400–x4FF
x400–x4FF
IFBNE 5JSR
B,#0B
SWAPALD
4,[B]
IFBIT
AND
A,[B]
JP+23 JP+76
JMP
x500–x5FF
x500–x5FF
IFBNE 6JSR
B,#0A
DCORALD
5,[B]
IFBIT
A,[B]
XOR
JP+24 JP+87
JMP
x600–x6FF
x600–x6FF
IFBNE 7JSR
B,#09
PUSHALD
6,[B]
A,[B]
JP+25 JP+98
JMP
x700–x7FF
x700–x7FF
IFBNE 8JSR
LD
B,#08
RBIT
7,[B]
JP+26 JP+10 9
JMP
x800–x8FF
x800–x8FF
IFBNE 9JSR
LD
B,#07
0,[B]
RBIT
0,[B]
IFNCSBIT
JP+27 JP+11 A
JMP
x900–x9FF
x900–x9FF
IFBNE 0AJSR
LD
B,#06
1,[B]
RBIT
1,[B]
INCASBIT
JP+28 JP+12 B
JMP
xA00–xAFF
xA00–xAFF
IFBNE 0BJSR
LD
B,#05
2,[B]
RBIT
2,[B]
DECASBIT
JP+29 JP+13 C
JMP
xB00–xBFF
xB00–xBFF
IFBNE 0CJSR
LD
B,#04
3,[B]
RBIT
3,[B]
JP+30 JP+14 D
JMP
xC00–xCFF
xC00–xCFF
IFBNE 0DJSR
LD
B,#03
4,[B]
RBIT
4,[B]
JP+31 JP+15 E
JMP
xD00–xDFF
xD00–xDFF
IFBNE 0EJSR
LD
B,#02
5,[B]
RBIT
5,[B]
JP+32 JP+16 F
JMP
xE00–xEFF
xE00–xEFF
IFBNE 0FJSR
LD
B,#01
6,[B]
RBIT
6,[B]
xF00–xFFF
xF00–xFFF
B,#00
7,[B]
7,[B]
14.0 Instruction Set (Continued)
A,#i
FE DC BA98765 432 10
JP−15JP−31LD 0F0, #iDRSZ 0F0RRCARCADC
A, #i
JP−14JP−30LD 0F1, #iDRSZ 0F1*SCSUBC
IFEQ
JP−13JP−29LD 0F2, #iDRSZ 0F2 X A,[X+]X
A,#i
IFGT
A,[B+]
JP−12JP−28LD 0F3, #iDRSZ 0F3 X A,[X−]X
A,#i
A,[B−]
JP−11JP−27LD 0F4, #iDRSZ 0F4VISLAIDADD
A,#i
JP−10JP−26LD 0F5, #iDRSZ 0F5RPNDJIDAND
A,#i
XOR
JP−9JP−25LD 0F6, #i DRSZ 0F6 X A,[X]X
A,#i
A,[B]
JP−8JP−24LD 0F7, #i DRSZ 0F7**OR A,#i OR A,[B] IFBIT
Where,i is the immediate dataMd is a directly addressed memory location* is an unused opcode The opcode 60 Hex is also the opcode for IFBIT #i,A
Page 54
COP8SG Family
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Page 55
15.0 Mask Options
See Section 5.5 ECON (CONFIGURATION) REGISTER.
16.0 COP8 Tools Overview
National is engaged with an international community of independent 3rd party vendors who provide hardware and
software development tool support. Through National’sinteraction and guidance, these tools cooperate to form a choice
of tools that fits each developer’s needs.
This section provides a summary of the tool and development kits currently available. Up-to-date information, selection guides, free tools, demos, updates, and purchase informationcanbeobtainedatourwebsiteat:
www.national.com/cop8.
16.1 SUMMARY OF TOOLS
COP8 Evaluation Software and Reference Designs
COP8–NSEVAL: Software Evaluation package for Win-
•
dows. A fully integrated evaluation environment for
COP8. Includes WCOP8 IDE evaluation version (Integrated Development Environment), COP8-NSASM (Full
COP8 Assembler), COP8-MLSIM (COP8 Instruction
Level Simulator), COP8C Compiler Demo, DriveWay
COP8 Device-Driver-Builder Demo, Manuals, Applications Software, and other COP8 technical information.
COP8–REF-xx: Reference Designs for COP8 Families.
•
Realtime hardware environment with a variety of functions for demonstrating the various capabilities and features of specific COP8 device families. Run Win 95 demo
reference software and exercise specific device capabilities.
COP8 Starter Kits and Hardware Target Solutions
COP8-EVAL-xxx: A variety of Multifunction Evaluation,
•
Design Test, and Target Boards for COP8 Families. Realtime target design environments with a selection of
peripherals and features including multi I/O, LCD display,
keyboard, A/D, D/A, EEPROM, USART, LEDs, and
bread-board area. Quickly design, test, and implement a
custom target system (some target boards are standalone, andready for mounting into a standard enclosure),
or just evaluate and test your code.
COP8 Software Development Languages and Integrated
Environments
COP8-NSDEV: National’s COP8 Software Development
•
package for Windows on CD. A fully Integrated Development Environment for COP8. Includes a fully licensed
WCOP8 IDE, COP8-NSASM. Plus Manuals, Applications
Software, and other COP8 technical information.
COP8C: ByteCraft - C Cross-Compiler and Code Devel-
•
opment System. Includes BCLIDE (Integrated Development Environment) for Win32, editor, optimizing C CrossCompiler, macro cross assembler, BC-Linker, and
MetaLinktools support. (DOS/SUN versions available.
COP8SG Family
EWCOP8, EWCOP8-M, EWCOP8-BL: IAR - ANSI
•
C-Compiler and Embedded Workbench. (M version includes MetaLink debugger support) (BL version: 4k code
limit; no FP). A fully integrated Win32 IDE, ANSI
C-Compiler, macro assembler, editor, linker, librarian,
and C-Spy high-level simulator/debugger.
Code Generation tool. Automatically generates tested
and documented C or Assembly source code modules
containing I/O drivers and interrupt handlers for each
on-chip peripheral. Application specific code can be inserted for customization using the integrated editor.
COP8-UTILS: COP8 assembly code examples, device
•
drivers, and utilities to speed up code development. (Included with COP8-NSDEV and COP8-NSEVAL.)
COP8 Hardware Debug Tools
COP8-EM-xx: Metalink COP8 Emulation Module for
•
OTP/ROM COP8 Families. Windows based development
and real-time in-circuit emulation tool, with 100 frame
trace, 32k s/w breaks, Enhanced User Interface, MetaLink Debugger. Includes COP8-NSDEV, power supply,
™
DIP emulation cables.
COP8-DM-xx: Metalink COP8 Debug Module for
•
OTP/ROM COP8 Families. Windows based development
and real-time in-circuit emulation tool, with 100 frame
trace, 32k s/w breaks, Basic User Interface, MetaLink
Debugger, and COP8 OTP Programmer with sockets.
Includes COP8-NSDEV, power supply, DIP and/or SMD
emulation cables and adapters.
COP8-IM: MetaLink iceMASTER®for OTP/ROM COP8
•
devices. Windows based, full featured real-time in-circuit
emulator, with 4k trace, 32k s/w breaks, and MetaLink
Windows Debugger. Includes COP8-NSDEV and power
supply. Package-specific probes and surface mount
adaptors are ordered separately. (Add COP8-PM and
adapters for OTP programming.)
COP8 Development and OTP Programming Tools
COP8-PM: COP8 Development Programming Module.
•
Windows programming tool for COP8 OTP/Flash Families. Includes 40 DIP programming socket, control software, RS232 cable, and power supply. (Programming
adapters are extra.)
Development: Metalink’s Debug Module includes devel-
•
opment device programming capability for COP8 devices. Many other third-party programmers are approved
for development and engineering use.
Production: Third-party programmers and automatic
•
handling equipment cover needs from engineering prototype and pilot production, to full production environments.
Factory Programming: Factory programming available
•
for high-volume requirements.
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Page 56
16.0 COP8 Tools Overview (Continued)
16.2 TOOLS ORDERING NUMBERS FOR THE COP8SGx FAMILY DEVICES
The COP8-IM/400 ICE can be used for emulation with the limitation of 10 MHz emulation speed maximum. For full speed
COP8SGx emulation, use the 15 MHz COP8-DM-SG or COP8-EM-SG.
Note: The following order numbers apply to the COP8 devices in this datasheet only.
COP8SG Family
VendorToolsOrder NumberCostNotes
COP8-NSEVALCOP8-NSEVALVLOrder from web site.
COP8-REFCOP8-REF-SGVLOrder from web site
COP8-EVALCOP8-EVAL-COB1VLOrder from web site
COP8-NSDEVCOP8-NSDEVVLIncluded in EM. Order CD from web site
COP8-EMCOP8-EM-SGMIncluded p/s, 28/40 pin DIP target cable, manuals,
MetaLink COP8-DMDM5-KCOP8-SGMIncluded p/s (PS-10), target cables (DIP and PLCC),
DM Target
Adapters
OTP Programming
Adapters
COP8-IMIM-COP8-AD-464 (-220)
IM Probe CardPC-COP8SG44PW-AD-10M10 MHz 44 PLCC probe card; 2.5V to 6.0V
IM Probe Target
Adapters
KKDWCOP8-IDEWCOP8-IDEVLIncluded in DM and EM
IAREWCOP8-xxSee summary aboveL - H Included all software and manuals
Byte
Craft
AisysDriveWay COP8DriveWay COP8LIncluded all software and manuals
Cost: Free; VL =
COP8CCOP8C COP8CWINMIncluded all software and manuals
OTP Programmers
<
$100; L = $100 - $300; M = $300 - $1k; H = $1k - $3k; VH = $3k - $5k
COP8-EMC-44PVL44 PLCC Target Cable
COP8-EMC-28CSPL28 CSP Target Cable
COP8-EMA-xxSOLDIP to SOIC Cable Converter
COP8-EMA-44QFPL44 pin PLCC to 44 QFP Cable Converter
COP8SGR7, COP8SGE7VL32k or 8k Eraseable/OTP devices
and 44 PLCC programming socket; add OTP adapter
or target adapter (if needed)
COP8-PGMA-44QFPLFor programming 44 QFP on any programmer
COP8-PGMA-28CSPLFor programming 28 CSP on any programmer
COP8-PGMA-44CSPLFor programming 44 CSP on any programmer
COP8-PGMA-28SOVLFor programming 16/20/28 SOIC on any programmer
16/20/28/40 DIP/SO and 44 PLCC programming
sockets. Add OTP adapter (if needed) and target
adapter (if needed)
MHW-CNVxx (xx = 33, 34
etc.)
MHW-COP8-PGMA-DSLFor programming 16/20/28 SOIC and 44 PLCC on the
MHW-COP8-PGMA-44QFP LFor programming 44 QFP on any programmer
MHW-COP8-PGMA-28CSP LFor programming 28 CSP on any programmer
28)
MHW-CONV33L44 pin QFP adapter for 44 PLCC probe card
Go to:
www.national.com/cop8
LDM target converters for
16DIP/20SO/28SO/44QFP/28CSP; (i.e. MHW-CNV38
for 20 pin DIP to SO package converter)
EPU
HBase unit 10 MHz; -220 = 220V; add probe card
(required) and target adapter (if needed); included
software and manuals
L16 or 20 or 28 pin SOIC adapter for probe card
L - H A wide variety world-wide
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Page 57
16.0 COP8 Tools Overview (Continued)
16.3 WHERE TO GET TOOLS
Tools can be ordered directly from National, National’s e-store, a National Distributor, or from the tool vendor. Go to the vendor’s
web site for current listings of distributors.
VendorHome OfficeElectronic SitesOther Main Offices
Byte Craft Limited421 King Street Northwww.bytecraft.comDistributors Worldwide
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;American Reliance; BP Microsystems; Data I/O; Dataman; EE Tools,Hi-Lo Systems; ICE Technology; KANDA, Lloyd
Research; Logical Devices; Minato; MQP; Needhams; Phyton; SMS(Data I/O); Stag Programmers; System General; and Tribal
Microsystems.
17.0 REVISION HISTORY
DateSectionSummary of Changes
October 2001Electrical CharacteristicsAdded spec. for comparator enable time.
COP8SG Family, 8-Bit CMOS ROM Based and OTP Microcontrollers with 8k to 32k Memory, Two
Plastic Quad Flat Package (VEJ)
Order Number COP8SGx544VEJx
NS Package Number VEJ44A
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
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.
labeling, can be reasonably expected to result in a
significant injury to the user.
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.
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