NSC COP8SAC7SLB9, COP8SAC7SLB8, COP8SAC744V9, COP8SAC744V7, COP8SAC744J3 Datasheet

...

COP8SA Family 8-Bit CMOS ROM Based and One-Time Programmable (OTP) Microcontroller with 1k to 4k Memory, Power On Reset, and Very Small Packaging

General Description

Note: COP8SAx devices are instruction set and pin compatible supersets of the COP800 Family devices, and are replacements for these in new designs when possible.

The COPSAx Rom based and OTP microcontrollers are highly integrated COP8

™

feature core devices, with1k to 4k memory and advanced features including low EMI. These single-chip CMOS devices are suited for low cost applications requiring a full featured controller, low EMI, and POR. 100%form-fit-function compatible OTP versions are available with 1k, 2k, and 4k memory, and in a variety of packages including 28-pin CSP.Erasable windowed versions are available for use with a range of COP8 software and hardware development tools.

Family features include an 8-bit memory mapped architecture, 10 MHz CKI with 1 µs instruction cycle, one multifunction 16-bit timer/counter with PWM output, MICROWIRE/PLUS

™

serial I/O, two power saving HALT/ IDLE modes, MIWU, idle timer, on-chip R/C oscillator, 12 high current outputs, user selectable options (WATCHDOG

™

, 4 clock/oscillator modes, power-on-reset), low EMI

2.7V to 5.5V operation, and 16/20/28/40/44 pin packages. Devices included in this datasheet are:

Device

Memory

(bytes)

RAM

(bytes)

I/O Pins

Packages Temperature

COP8SAA5 1k ROM 64 12/16/24 16/20/28 DIP/SOIC 0 to +70˚C, -40 to +85˚C,

-40 to +125˚C

COP8SAB5 2k ROM 128 16/24 20/28 DIP/SOIC 0 to +70˚C, -40 to +85˚C,

-40 to +125˚C

COP8SAC5 4k ROM 128 16/24/36/40 20/28 DIP/SOIC, 28 CSP,

40 DIP, 44 PLCC/QFP

0 to +70˚C, -40 to +85˚C,

-40 to +125˚C

COP8SAA7 1k OTP EPROM 64 12/16/24 16/20/28 DIP/SOIC 0 to +70˚C, -40 to +85˚C,

-40 to +125˚C

COP8SAB7 2k OTP EPROM 128 16/24 20/28 DIP/SOIC 0 to +70˚C, -40 to +85˚C,

-40 to +125˚C

COP8SAC7 4k OTP EPROM 128 16/24 20/28 DIP/SOIC, 28 CSP,

40 DIP, 44 PLCC/QFP

0 to +70˚C, -40 to +85˚C,

-40 to +125˚C COP8SAA7SLB9 1k OTP EPROM 64 24 28 CSP 0 to +70˚C COP8SAB7SLB9 2k OTP EPROM 128 24 28 CSP 0 to +70˚C COP8SAC7SLB9 4k OTP EPROM 128 24 28 CSP 0 to +70˚C COP8SAC7-Q3 4k EPROM 128 16/24/36 20/28/40 DIP Room Temp. Only COP8SAC7-J3 4k EPROM 128 40 44 PLCC Room Temp. Only

Key Features

n Low cost 8-bit OTP microcontroller n OTP program space with read/write protection (fully

secured)

n Quiet Design (low radiated emissions) n Multi-Input Wakeup pins with optional interrupts

(4 to 8 pins)

n 8 bytes of user storage space in EPROM

n User selectable clock options

— Crystal/Resonator options — Crystal/Resonator option with on-chip bias resistor — External oscillator — Internal R/C oscillator

n Internal Power-On Reset—user selectable n WATCHDOG and Clock Monitor Logic—user selectable n Up to 12 high current outputs

TRI-STATE®is a registered trademark of National Semiconductor Corporation. MICROWIRE/PLUS

™

, COP8™, MICROWIRE™and WATCHDOG™are trademarks of National Semiconductor Corporation.

iceMASTER

is a registered trademark of MetaLink Corporation.

PRELIMINARY

July 1999

COP8SA Family, 8-Bit CMOS ROM Based and One-Time Programmable (OTP) Microcontroller

with 1k to 4k Memory, Power On Reset, and Very Small Packaging

CPU Features

n Versatile easy to use instruction set n 1 µs instruction cycle time n Eight multi-source vectored interrupts servicing

— External interrupt — Idle Timer T0 — One Timer (with 2 interrupts) — MICROWIRE/PLUS Serial Interface — Multi-Input Wake Up — Software Trap — 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 Memory mapped I/O n BCD arithmetic instructions

Peripheral Features

n Multi-Input Wakeup Logic n One 16-bit timer with two 16-bit registers supporting:

— Processor Independent PWM mode — External Event counter mode — Input Capture mode

n Idle Timer n MICROWIRE/PLUS Serial Interface (SPI Compatible)

I/O Features

n Software selectable I/O options

— TRI-STATE

Output — Push-Pull Output — Weak Pull Up Input — High Impedance Input

n Schmitt trigger inputs on ports G and L n Up to 12 high current outputs n Pin efficient (i.e., 40 pins in 44-pin package are devoted

to useful I/O)

Fully Static CMOS Design

n Low current drain (typically<4 µA) n Single supply operation: 2.7V to 5.5V n Two power saving modes: HALT and IDLE

Temperature Ranges

0˚C to +70˚C, −40˚C to +85˚C, and −40˚C to +125˚C

Development Support

n Windowed packages for DIP and PLCC n Real time emulation and full program debug offered by

MetaLink Development System

Block Diagram

DS012838-1

FIGURE 1. COP8SAx Block Diagram

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General Description (Continued)

Key features include an 8-bit memory mapped architecture, a 16-bit timer/counter with two associated 16-bit registers supporting three modes (Processor Independent PWM generation, External Event counter, and Input Capture capabilities), two power saving HALT/IDLE modes with a multi-sourced wakeup/interrupt capability, on-chip R/C oscillator, high current outputs, user selectable options such as WATCHDOG, Oscillator configuration, and power-on-reset.

1.1 EMI REDUCTION

The COP8SAx 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 helpcircumvent manyof the EMI issues influencing embedded control designs. National has achieved 15 dB–20 dB reduction in EMI transmissionswhen designs have incorporated its patented EMI reducing circuitry.

1.2 ARCHITECTURE

The COP8SAx 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 usually need to be contained in ROM or EPROM, 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 witha Von Neumann single-addressbus architecture.

The COP8SAx 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.

1.3 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 issuescan be addressed through themanner 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 tomarket that today’s microcontroller based products require.

Code efficiency is important because it enables designers to pack more on-chip functionality into less program memory space (ROM/OTP). 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.

1.3.1 Key Instruction Set Features

The COP8SAx 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 thesingle bytevariety, resulting in minimumprogram space. Because compact code does not occupya substantial amount of program memory space, designers can integrate additional features and functionality into the microcontroller program memory space. Also, the majorityinstructions 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 greatercode and I/O efficiency, and faster code execution.

1.3.2 Many Single-Byte, Multifunction Instructions

The COP8SAx instruction set utilizesmany single-byte, multifunction instructions. This enablesa single instruction to accomplish multiple functions, such as DRSZ,DCOR, JID, and LOAD/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: (Load Accumulator-Indirect); Single byte look up table instruction provides efficient data path from the program memory to the CPU. This instruction can be used for table lookup and to read the entire program memory for checksum calculations.

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 (analogousto “FOR NEXT” in higher level languages).

1.3.3 Bit-Level Control

Bit-level control over many of the microcontroller’s I/O ports provides a flexiblemeans to ease layout concernsand save board space. All members of the COP8 family provide the ability to set, reset and test any individual bit in the data memory address space, including memory-mapped I/O ports and associated registers. Three memory-mapped pointers handle register indirect addressing and software stack pointer functions. The memory data pointers allow the option of post-incrementing or post-decrementing with the data movement instructions (LOAD/EXCHANGE). And 15 memory-maped registers allow designers to optimize the precise implementation of certain specific instructions.

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 COP8 family offersa 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.

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Connection Diagrams

DS012838-2

Top View

DS012838-3

Top View

DS012838-4

Top View

DS012838-39

Top View

DS012838-5

Top View

DS012838-6

Top View

FIGURE 2. Connection Diagrams

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Ordering Information

1k EPROM 2k EPROM 4k EPROM 4k EPROM

Windowed

Device

Temperature Order Number Package Order Number Package Order Number Package Order Number Package

0˚C to +70˚C COP8SAA716M9 16M

COP8SAA720M9 20M COP8SAB720M9 20M COP8SAC720M9 20M COP8SAA728M9 28M COP8SAB728M9 28M COP8SAC728M9 28M COP8SAA716N9 16N COP8SAA720N9 20N COP8SAB720N9 20N COP8SAC720N9 20N COP8SAC720Q3 20Q COP8SAA728N9 28N COP8SAB728N9 28N COP8SAC728N9 28N COP8SAC728Q3 28Q

COP8SAC740N9 40N COP8SAC740Q3 40Q COP8SAC744V9 44V COP8SAC744J3 44J

−40˚C to +85˚C COP8SAA716M8 16M COP8SAA720M8 20M COP8SAB720M8 20M COP8SAC720M8 20M COP8SAA728M8 28M COP8SAB728M8 28M COP8SAC728M8 28M COP8SAA716N8 16N COP8SAA720N8 20N COP8SAB720N8 20N COP8SAC720N8 20N COP8SAA728N8 28N COP8SAB728N8 28N COP8SAC728N8 28N

COP8SAC740N8 40N COP8SAC744V8 44V

COP8SAA7SLB8 SLB COP8SAB7SLB8 SLB COP8SAC7SLB8 SLB

−40˚C to +125˚C

COP8SAC720M7 20M COP8SAC728M7 28M COP8SAC720N7 20N COP8SAC728N7 28N COP8SAC740N7 40N COP8SAC744V7 44V

DS012838-8

FIGURE 3. Part Numbering Scheme

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4.0 Electrical Characteristics Absolute Maximum Ratings

(Note 1)

If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications.

Supply Voltage (V

)7V

Voltage at Any Pin −0.6V to V

+0.6V

ESD Protection Level 2 kV

(Human Body Model)

Total Current into V

Pin (Source) 80 mA Total Current out of GND Pin (Sink) 100 mA Storage Temperature Range −65˚C to +140˚C

Note 1:

Absolute maximum ratings indicate limits beyond which damage to the device may occur. DC and AC electrical specifications are not ensured when operating the device at absolute maximum ratings.

DC Electrical Characteristics

0˚C ≤ TA≤ +70˚C unless otherwise specified.

Parameter Conditions Min Typ Max Units

Operating Voltage (Note 8) 2.7 5.5 V Power Supply Rise Time from 0.0V

(On-Chip Power-On Reset Selected) 10 ns 50 ms

Start Voltage to Guarantee POR 0.25 V

Power Supply Ripple (Note 3) Peak-to-Peak 0.1 V

Supply Current (Note 4)

CKI=10 MHz V

5.5V, t

1µs 6 mA

CKI=4 MHz V

4.5V, t

2.5 µs 2.1 mA

HALT Current (Note 5) —WATCHDOG Disabled V

5.5V, CKI=0 MHz

48 µA

IDLE Current (Note 4)

CKI=10 MHz V

5.5V, t

1 µs 1.5 mA

CKI=4 MHz V

4.5V, t

2.5 µs 0.8 mA

Input Levels (V

IH,VIL

)

RESET

Logic High 0.8 V

Logic Low 0.2 V

CKI, All Other Inputs

Logic High 0.7 V

Logic Low 0.2 V

V Value of the Internal Bias Resistor 0.5 1.0 2.0 MΩ for the Crystal/Resonator Oscillator CKI Resistance to V

or GND when R/C V

5.5V 5 8 11 kΩ Oscillator is Selected Hi-Z Input Leakage (same as TRI-STATE output) V

5.5V −2 +2 µA Input Pullup Current V

5.5V, V

0V −40 −250 µA

G and L Port Input Hysteresis 0.25 V

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DC Electrical Characteristics (Continued)

0˚C ≤ TA≤ +70˚C unless otherwise specified.

Parameter Conditions Min Typ Max Units

Output Current Levels D Outputs

Source V

4.5V, V

3.3V −0.4 mA

2.7V, V

1.8V −0.2 mA

Sink V

4.5V, V

1.0V 10 mA

2.7V, V

0.4V 2 mA

L Port

Source (Weak Pull-Up) V

4.5V, V

2.7V −10 −110 µA

2.7V, V

1.8V −2.5 −33 µA

Source (Push-Pull Mode) V

4.5V, V

3.3V −0.4 mA

2.7V, V

1.8V −0.2 mA

Sink (L0–L3, Push-Pull Mode) V

4.5V, V

1.0V 10 mA

2.7V, V

0.4V 2 mA

Sink (L4–L7, Push-Pull Mode) V

4.5V, V

0.4V 1.6 mA

2.7V, V

0.4V 0.7 mA

All Others

Source (Weak Pull-Up Mode) V

4.5V, V

2.7V −10 −110 µA

2.7V, V

1.8V −2.5 −33 µA

Source (Push-Pull Mode) V

4.5V, V

3.3V −0.4 mA

2.7V, V

1.8V −0.2 mA

Sink (Push-Pull Mode) V

4.5V, V

0.4V 1.6 mA

2.7V, V

0.4V 0.7 mA

Allowable Sink Current per Pin (Note 8)

D Outputs and L0 to L3 15 mA All Others 3mA

Maximum Input Current without Latchup

200 mA (Note 6) RAM Retention Voltage, Vr 2.0 V V

Rise Time from a VCC≥ 2.0V (Note 9) 12 µs Input Capacitance (Note 8) 7 pF Load Capacitance on D2 (Note 8) 1000 pF

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AC Electrical Characteristics

0˚C ≤ TA≤ +70˚C unless otherwise specified.

Parameter Conditions Min Typ Max Units

Instruction Cycle Time (t

)

Crystal/Resonator, External 4.5V ≤ V

≤ 5.5V 1.0 DC µs

2.7V ≤ V

4.5V 2.0 DC µs

Internal R/C Oscillator 4.5V ≤ V

≤ 5.5V 2.0 µs

2.7V ≤ V

4.5V TBD µs

R/C Oscillator Frequency Variation 4.5V ≤ V

≤ 5.5V

(Note 8) 2.7V ≤ V

4.5V TBD

External CKI Clock Duty Cycle (Note 8) fr=Max 45 55

% Rise Time (Note 8) fr=10 MHz Ext Clock 12 ns Fall Time (Note 8) fr=10 MHz Ext Clock 8 ns

Inputs

SETUP

4.5V ≤ VCC≤ 5.5V 200 ns

2.7V ≤ V

4.5V 500 ns

HOLD

4.5V ≤ VCC≤ 5.5V 60 ns

2.7V ≤ V

4.5V 150 ns

Output Propagation Delay (Note 7) R

2.2k, C

100 pF

PD1,tPD0

SO, SK 4.5V ≤ VCC≤ 5.5V 0.7 µs

2.7V ≤ V

4.5V 1.75 µs

All Others 4.5V ≤ V

≤ 5.5V 1.0 µs

2.7V ≤ V

4.5V 2.5 µs

MICROWIRE Setup Time (t

UWS

) (Note 7) 20 ns

MICROWIRE Hold Time (t

UWH

) (Note 7) 56 ns

MICROWIRE Output Propagation Delay (t

UPD

) 220 ns

MICROWIRE Maximum Shift Clock

Master Mode 500 kHz Slave Mode 1 MHz

Input Pulse Width (Note 7)

Interrupt Input High Time 1 t

Interrupt Input Low Time 1 t

Timer 1 Input High Time 1 t

Timer 1 Input Low Time 1 t

Reset Pulse Width 1 µs

Note 2: t

Instruction cycle time (Clock input frequency divided by 10).

Note 3: Maximum rate of voltage change must be

0.5 V/ms.

Note 4: Supply and IDLE currents are measured with CKI driven with a square wave Oscillator, CKO driven 180˚ out of phase with CKI, inputs connected to V

and outputs driven low but not connected to a load. Note 5: TheHALT mode 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

HALT is done with device neither sourcingnor sinking current; with L. F, C, G0, and G2–G5 pro-

grammed as low outputs and not driving a load; all outputs programmed low and not driving a load; all inputs tied to V

; WATCHDOGand clock monitor disabled.

Parameter refers to HALT mode entered via setting bit 7 of the G Port data register. Note 6: PinsG6 and RESET are designed with a high voltage input network. These pins allow input voltages

VCCand the pins will have sink current to VCCwhen biased at voltages>VCC(the pins do not have source current when biasedat 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

14V.WARNING: Voltages in excess of 14V will cause damage to the pins. This warning ex-

cludes ESD transients. Note 7: The output propagation delay is referenced to the end of the instruction cycle where the output change occurs. Note 8: Parameter characterized but not tested. Note 9: Rise times faster than this specification may reset the device if POR is enabled and may affectthe value of IdleTimer T0 if POR is not enabled.

www.national.com 8

Absolute Maximum Ratings (Note 10)

If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications.

Supply Voltage (V

)7V

Voltage at Any Pin −0.6V to V

+0.6V

ESD Protection Level 2 kV

(Human Body Model)

Total Current into V

Pin (Source) 80 mA Total Current out of GND Pin (Sink) 100 mA Storage Temperature Range −65˚C to +140˚C

Note 10:

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.

DC Electrical Characteristics

−40˚C ≤ TA≤ +85˚C unless otherwise specified.

Parameter Conditions Min Typ Max Units

Operating Voltage 2.7 5.5 V Power Supply Rise Time from 0.0V (Note 17)

(On-Chip Power-On Reset Selected) 10 ns 50 ms

Start Voltage to Guarantee POR 0.25 V

Power Supply Ripple (Note 12) Peak-to-Peak 0.1 V

Supply Current (Note 13)

CKI=10 MHz V

5.5V, t

1 µs 6.0 mA

HALT Current (Note 14) —WATCHDOG Disabled V

5.5V, CKI=0 MHz

4 10.0 µA

IDLE Current (Note 13)

CKI=10 MHz V

5.5V, t

1 µs 1.5 mA

Input Levels (V

IH,VIL

)

RESET

Logic High 0.8 V

Logic Low 0.2 V

CKI, All Other Inputs

Logic High 0.7 V

Logic Low 0.2 V

V Value of the Internal Bias Resistor 0.5 1.0 2.0 MΩ for the Crystal/Resonator Oscillator CKI Resistance to V

or GND when R/C V

5.5V 5 8 11 kΩ Oscillator is Selected Hi-Z Input Leakage (same as TRI-STATE output) V

5.5V −2 +2 µA Input Pullup Current V

5.5V, V

0V −40 −250 µA

G and L Port Input Hysteresis 0.25 V

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DC Electrical Characteristics (Continued)

−40˚C ≤ TA≤ +85˚C unless otherwise specified.

Parameter Conditions Min Typ Max Units

Output Current Levels D Outputs

Source V

4.5V, V

3.3V −0.4 mA

2.7V, V

1.8V −0.2 mA

Sink V

4.5V, V

1.0V 10 mA

2.7V, V

0.4V 2 mA

L Port

Source (Weak Pull-Up) V

4.5V, V

2.7V −10.0 −110 µA

2.7V, V

1.8V −2.5 −33 µA

Source (Push-Pull Mode) V

4.5V, V

3.3V −0.4 mA

2.7V, V

1.8V −0.2 mA

Sink (L0–L3, Push-Pull Mode) V

4.5V, V

1.0V 10.0 mA

2.7V, V

0.4V 2 mA

Sink (L4–L7, Push-Pull Mode) V

4.5V, V

0.4V 1.6 mA

2.7V, V

0.4V 0.7 mA

All Others

Source (Weak Pull-Up Mode) V

4.5V, V

2.7V −10.0 −110 µA

2.7V, V

1.8V −2.5 −33 µA

Source (Push-Pull Mode) V

4.5V, V

3.3V −0.4 mA

2.7V, V

1.8V −0.2 mA

Sink (Push-Pull Mode) V

4.5V, V

0.4V 1.6 mA

2.7V, V

0.4V 0.7 mA

Allowable Sink Current per Pin (Note 17)

D Outputs and L0 to L3 15 mA All Others 3mA

Maximum Input Current without Latchup (Note 15)

200 mA RAM Retention Voltage, Vr 2.0 V V

Rise Time from a VCC≥ 2.0V (Note 18) 12 µs Input Capacitance (Note 17) 7 pF Load Capacitance on D2 (Note 17) 1000 pF

AC Electrical Characteristics

−40˚C ≤ TA≤ +85˚C unless otherwise specified.

Parameter Conditions Min Typ Max Units

Instruction Cycle Time (t

)

Crystal/Resonator, External 4.5V ≤ V

≤ 5.5V 1.0 DC µs

2.7V ≤ V

4.5V 2.0 DC µs

Internal R/C Oscillator 4.5V ≤ V

≤ 5.5V 2.0 µs

2.7V ≤ V

4.5V TBD µs

R/C Oscillator Frequency Variation 4.5V ≤ V

≤ 5.5V

(Note 17) 2.7V ≤ V

4.5V TBD

External CKI Clock Duty Cycle (Note 17) fr=Max 45 55

% Rise Time (Note 17) fr=10 MHz Ext Clock 12 ns Fall Time (Note 17) fr=10 MHz Ext Clock 8 ns

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AC Electrical Characteristics (Continued)

−40˚C ≤ TA≤ +85˚C unless otherwise specified.

Parameter Conditions Min Typ Max Units

Inputs

SETUP

4.5V ≤ VCC≤ 5.5V 200 ns

2.7V ≤ V

4.5V 500 ns

HOLD

4.5V ≤ VCC≤ 5.5V 60 ns

2.7V ≤ V

4.5V 150 ns

Output Propagation Delay (Note 16) R

2.2k, C

100 pF

PD1,tPD0

SO, SK 4.5V ≤ VCC≤ 5.5V 0.7 µs

2.7V ≤ V

4.5V 1.75 µs

All Others 4.5V ≤ V

≤ 5.5V 1.0 µs

2.7V ≤ V

4.5V 2.5 µs

MICROWIRE Setup Time (t

UWS

) (Note 16) 20 ns

MICROWIRE Hold Time (t

UWH

) (Note 16) 56 ns

MICROWIRE Output Propagation Delay (t

UPD

) 220 ns

MICROWIRE Maximum Shift Clock

Master Mode 500 kHz Slave Mode 1 MHz

Input Pulse Width (Note 17)

Interrupt Input High Time 1 t

Interrupt Input Low Time 1 t

Timer 1 Input High Time 1 t

Timer 1 Input Low Time 1 t

Reset Pulse Width 1 µs

Note 11: t

Instruction cycle time (Clock input frequency divided by 10).

Note 12: Maximum rate of voltage change must be

0.5 V/ms.

Note 13: Supply and IDLE currents are measured with CKI driven with a square wave Oscillator, CKO driven 180˚ out of phase with CKI, inputs connected to V

and outputs driven low but not connected to a load. Note 14: TheHALTmode 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

HALT is done with device neither sourcingnor sinking current; with L. F, C, G0, and G2–G5 pro-

grammed as low outputs and not driving a load; all outputs programmed low and not driving a load; all inputs tied to V

; clock monitor disabled. Parameter refers

to HALT mode entered via setting bit 7 of the G Port data register. Note 15: PinsG6 and RESET are designed with a high voltage input network. These pins allow input voltages

14V.WARNING: Voltages in excess of 14V will cause damage to the pins. This warning excludes

ESD transients.

Note 16: The output propagation delay is referenced to the end of the instruction cycle where the output change occurs. Note 17: Parameter characterized but not tested. Note 18: Rise times faster than this specification may reset the device if POR is enabled and may affectthe value of IdleTimer T0 if POR is not enabled.

DS012838-9

FIGURE 4. MICROWIRE/PLUS Timing

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Absolute Maximum Ratings (Note 19)

If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications.

Supply Voltage (V

)7V

Voltage at Any Pin −0.6V to V

+0.6V

ESD Protection Level 2 kV

(Human Body Model)

Total Current into V

Pin (Source) 80 mA Total Current out of GND Pin (Sink) 100 mA Storage Temperature Range −65˚C to +140˚C

Note 19:

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.

DC Electrical Characteristics

−40˚C ≤ TA≤ +125˚C unless otherwise specified.

Parameter Conditions Min Typ Max Units

Operating Voltage 4.5 5.5 V Power Supply Rise Time from 0.0V (Note 17)

(On-Chip Power-On Reset Selected) 10 ns 50 ms

Start Voltage to Guarantee POR 0.25 V

Power Supply Ripple (Note 12) Peak-to-Peak 0.1 V

Supply Current (Note 13)

CKI=10 MHz V

5.5V, t

1 µs 6.0 mA

HALT Current (Note 14) —WATCHDOG Disabled

5.5V, CKI=0 MHz

10 30 µA

IDLE Current (Note 13)

CKI=10 MHz V

5.5V, t

1 µs 1.5 mA

Input Levels (V

IH,VIL

)

RESET

Logic High 0.8 V

Logic Low 0.2 V

CKI, All Other Inputs

Logic High 0.7 V

Logic Low 0.2 V

V Value of the Internal Bias Resistor 0.5 1.0 2.0 MΩ for the Crystal/Resonator Oscillator CKI Resistance to V

or GND when R/C V

5.5V 5 8 11 kΩ Oscillator is Selected Hi-Z Input Leakage V

5.5V −5 +5 µA Input Pullup Current V

5.5V, V

0V −35 −400 µA

G and L Port Input Hysteresis 0.25 V

V Output Current Levels D Outputs

Source V

4.5V, V

3.3V −0.4 mA

Sink V

4.5V, V

1.0V 9 mA

L Port

Source (Weak Pull-Up) V

4.5V, V

2.7V −9 −140 µA

Source (Push-Pull Mode) V

4.5V, V

3.3V −0.4 mA

Sink (L0–L3, Push-Pull Mode) V

4.5V, V

1.0V 9 mA

Sink (L4–L7, Push-Pull Mode) V

4.5V, V

0.4V 1.4 mA

All Others

Source (Weak Pull-Up Mode) V

4.5V, V

2.7V −9 −140 µA

Source (Push-Pull Mode) V

4.5V, V

3.3V −0.4 mA

Sink (Push-Pull Mode) V

4.5V, V

0.4V 1.4 mA

TRI-STATE Leakage V

5.5V −5 +5 µA

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DC Electrical Characteristics (Continued)

−40˚C ≤ TA≤ +125˚C unless otherwise specified.

Parameter Conditions Min Typ Max Units

Allowable Sink Current per Pin (Note 17)

D Outputs and L0 to L3 15 mA All Others 3mA

Maximum Input Current without Latchup Room Temp

200 mA (Note 15) RAM Retention Voltage, Vr 2.0 V V

Rise Time from a VCC≥ 2.0V (Note 18) 12 µs Input Capacitance (Note 17) 7 pF Load Capacitance on D2 (Note 17) 1000 pF

AC Electrical Characteristics

−40˚C ≤ TA≤ +125˚C unless otherwise specified.

Parameter Conditions Min Typ Max Units

Instruction Cycle Time (t

)

Crystal/Resonator, External 4.5V ≤ V

≤ 5.5V 1.0 DC µs

Internal R/C Oscillator 4.5V ≤ V

≤ 5.5V 2.0 DC µs

R/C Oscillator Frequency Variation 4.5V ≤ V

≤ 5.5V TBD

(Note 6)

External CKI Clock Duty Cycle (Note 6) fr=Max 45 55

% Rise Time (Note 6) fr=10 MHz Ext Clock 12 ns Fall Time (Note 6) fr=10 MHz Ext Clock 8 ns

Inputs

SETUP

4.5V ≤ VCC≤ 5.5V 200 ns

HOLD

4.5V ≤ VCC≤ 5.5V 60 ns

Output Propagation Delay (Note 5) R

2.2k, C

100 pF

PD1,tPD0

SO, SK 4.5V ≤ VCC≤ 5.5V 0.7 µs All Others 4.5V ≤ V

≤ 5.5V 1.0 µs

MICROWIRE Setup Time (t

UWS

) (Note 5) 20 ns

MICROWIRE Hold Time (t

UWH

) (Note 5) 56 ns

MICROWIRE Output Propagation Delay (t

UPD

) 220 ns

MICROWIRE Maximum Shift Clock

Master Mode 500 kHz Slave Mode 1 MHz

Input Pulse Width (Note 6)

Interrupt Input High Time 1 t

Interrupt Input Low Time 1 t

Timer 1, 2, 3 Input High Time 1 t

Timer 1, 2, 3 Input Low Time 1 t

Reset Pulse Width 1 µs

www.national.com13

5.0 Pin Descriptions

COP8SAx I/O structure minimizes external component requirements. Software-switchable I/O enables designers to reconfigure the microcontroller’s I/O functions with a single instruction. Each individual I/O pin can be independently configured as an output pin low, an output high, an input with high impedance or an inputwith a weak pull-up device.A typical example is the use ofI/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 up. 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 pullupwill pull the input line back to logic high. This flexibility eliminates the need for external pull-up resistors. The Highcurrent 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 thegeneral description of all available pins.

and GND are the power supply pins. All VCCand

GND 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.

The 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/Oport has two associated 8-bit memory mapped registers, the CONFIGURATION register and the output DATAregister. A memory mapped address is also reserved for the input pins of each I/O port. (See thememory map for the various addresses associated with the I/O ports.)

Figure 5

shows the I/O port configurations. The DATA and CONFIGURATION registers allow for each port bit to be individually configured under software control as shown below:

CONFIGURATION DATA Port Set-Up

0 0 Hi-Z Input

(TRI-STATE Output) 0 1 Input with Weak Pull-Up 1 0 Push-Pull Zero Output 1 1 Push-Pull One Output

Port L is an 8-bit I/O port. All L-pins haveSchmitt triggers on the inputs.

Port L supports the Multi-Input Wake Up feature on all eight pins. The 16-pin device does not have a full complement of Port L pins. The unavailable pins are not terminated. Aread operation these unterminated pins are not terminated.A read operation these unterminated pins will return unpredictable values. To minimize current drain, the unavailable pins must be programmed as outputs.

Port G is an 8-bit port. Pin G0, G2–G5 are bi-directional I/O ports. Pin G6 is always a general purposeHi-Z input. All pins have Schmitt Triggers on theirinputs. Pin G1 serves as the

dedicated WDOUT WATCHDOG output with weakpullup if WATCHDOG feature is selected by the ECON register. The pin is a general purpose I/O if WATCHDOGfeature is

not selected. If WATCHDOG feature is selected, bit 1of the

Port G configuration anddata 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. There are two registers associated with Port G, a data register and a configuration register. Using these registers, each of the 5 I/O pins (G0, G2–G5) can be individually configured under software control.

Since G6 is an input only pin and G7 is the dedicated CKO clock output pin (crystal clock option) or general purpose input (R/C or external clock option), the associated bits in the data and configuration registers for G6 and G7 are used for special purpose functions as outlined below. Reading the G6 and G7 data bits will return zeroes.

The device will be placed in the HALT mode 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 ConfigurationRegister 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.

G7 CLKDLY HALT

G6 Alternate SK IDLE Port G has the following alternate features: 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) G0 INTR (External Interrupt Input) Port G has the following dedicated functions: G7 CKO Oscillator dedicated output or general purpose in-

put G1 WDOUTWATCHDOGand/or CLock Monitor if WATCH-

DOG enabled, otherwise it is a general purpose I/O 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. Only the COP8SAC7 device contains Port C. The 20/28 pin devices do not offer Port C. On these devices, 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.

www.national.com 14

5.0 Pin Descriptions (Continued)

Port D is an 8-bit output port that is preset high when 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 ex-

ternal loads on this pin must ensure that the output voltages stay above 0.7 V

to prevent the chip from entering special modes.Also

keep the external loading on D2 to less than 1000 pF.

6.0 Functional Description

The architecture of the device is a modified Harvard architecture. With the Harvard architecture, the program memory EPROM is separated from the data store memory (RAM). Both EPROM and RAM have their own separate addressing space with separate address buses. The architecture, though based on the Harvard architecture, permits transfer of data from EPROM to RAM.

6.1 CPU REGISTERS

The CPU can do an 8-bit addition, subtraction, logical or shift operation in one instruction (t

) cycle time. There are six CPU registers: A is the 8-bit Accumulator Register PC is the 15-bit Program Counter Register

PU is the upper 7 bits of the program counter (PC) PL is the lower 8 bits of the program counter (PC)

B is an 8-bit RAM address pointer, which can be optionally post auto incremented or decremented.

X is an 8-bit alternate RAM address pointer, which can be optionally post auto incremented or decremented.

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).

6.2 PROGRAM MEMORY

The program memory consists of 1024, 2048, or 4096 bytes of EPROM or ROM.

Table 1

shows the program memory sizes for the different devices. These bytes may hold program instructions or constant data (data tables for the LAID instruction, jump vectors for theJID instruction, andinterrupt vectors for the VIS instruction). The program memory is addressed by the 15-bit program counter (PC). All interrupts in the device vector to programmemory location0FF Hex. The contents of the program memory read 00 Hex in the erased state.

6.3 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 consistsof 64or 128bytes of RAM.

Table

shows the data memory sizesfor thedifferent devices. Fifteen bytes of RAM are mapped as “registers” at addresses 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 mappedinto this space at address locations 0FC to 0FE Hex respectively, with the other registers (except 0FF) being available for general usage.Address location 0FF is reserved for future RAM expansion. If compatibility with future devices (with more RAM) is not desired, this location can be used as a general purpose RAM location.

DS012838-10

FIGURE 5. I/O Port Configurations

DS012838-12

FIGURE 6. I/O Port Configurations— Output Mode

DS012838-11

FIGURE 7. I/O Port Configurations— Input Mode

www.national.com15

6.0 Functional Description (Continued)

The instruction set permits any bitin memory to beset, reset or tested. All I/O and registers (except A and PC) are memory mapped; therefore,I/O bits and register bitscan be directly and individually set, reset and tested. The accumulator (A) bits can also be directly and individually tested.

RAM contents are undefined upon power-up.

TABLE 1. Program/Data Memory Sizes

Program Data User

Device Memory Memory Storage

(Bytes) (Bytes) (Bytes)

COP8SAA7 1024 64 8 COP8SAB7 2048 128 8 COP8SAC7 4096 128 8

6.4 ECON (CONFIGURATION) REGISTER

The ECON register is used to configure the user selectable clock, security, power-on reset, WATCHDOG, and HALT options. The register can be programmed and read only in EPROM programming mode. Therefore, the register should be programmed at the same time as the program memory. The contents of the ECON register shipped from the factory read 00 Hex (windowed device), 80 Hex (OTP device) or as specified by the customer (ROM device).

The format of the ECON register is as follows:

Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

X POR SECURITY CKI 2 CKI 1 WATCH Reserved HALT

DOG

Bit 7=x This is for factory test. The polarity is al-

ways 0.

Bit 6=1 Power-on reset enabled.

0 Power-on reset disabled.

Bit 5=1 Security enabled. EPROM read and write

are not allowed.

0 Security disabled. EPROM read and write

are allowed.

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) is the clock generator output to crystal/resonator.

Bit 2=1 WATCHDOG feature disabled. G1 is a

general purpose I/O.

0 WATCHDOG feature enabled. G1 pin is

WATCHDOG output with waek pullup.

Bit 1

Reserved.

Bit 0=1 HALT mode disabled.

0 HALT mode enabled.

6.5 USER STORAGE SPACE IN EPROM

In addition to the ECON register, there are 8 bytes of EPROM available for “user information”. ECON and these 8 bytes are outside of the code area and are not protected by the security bit of the ECON register. Even when security is set, information in the 8-byte USER area is both read and write enabled allowing the user to read from and write into the area at all times while still protecting the code fromunauthorized access.

Both ECON and USER area,9 bytes total,are outside of the normal address range of the EPROM and can not be accessed by the executing software. This allows for the storage of non-secured information. Typical uses arefor storage of serial numbers, data codes, version numbers, copyright information, lot numbers, etc.

The COP8 assembler defines a special ROM section type, CONF, into which theECON and USER data 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:] .sect econ, conf

.db value ;1 byte,

;configures options .db .endsect<user information>

;up to 8 bytes

Example: The following sets a value in the ECON register and User Identification for a COP8SAC728M7. The ECON bit values shown selectoptions: Power-on enabled,Security disabled, Crystal oscillator with on-chip bias disabled, WATCHDOG enabled and HALT mode enabled.

.chip 8SAC .sect econ, conf .db 0x55 ;por, extal, wd, halt .db 'my v1.00' ;user data declaration .endsect ... .end start

Note: All programmers certified for programming this family of parts will sup-

port programming of the CONFiguration section. Please contact National or your device programmer supplier for more information.

6.6 OTP SECURITY

The device has a security feature that, when enabled, prevents external reading of theOTP 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, thenany attempt to externally read the contents of the EPROM will result in the value FF Hex beingread fromall program locations. Under no circumstances can a secured part be read. In ad-

dition, with the security feature enabled, the write operation to the EPROM program memory and ECONregister 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 set in a device in a windowed package, that device may be erased but will not be further programmable.

If security is being used, itis recommended that allother bits in the ECON register beprogrammed first.Then the security bit can be programmed.

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6.0 Functional Description (Continued)

6.7 RESET

The device is initialized whenthe RESET pinis pulled lowor the On-chip Power-On Reset is enabled.

The following occurs upon initialization:

Port L: TRISTATE Port C: TRISTATE Port G: TRISTATE Port F: TRISTATE Port D: HIGH PC: CLEARED to 0000 PSW, CNTRL and ICNTRL registers: CLEARED SIOR: UNAFFECTED after RESET with power already

applied

RANDOM after RESET at power-on T1CNTRL: CLEARED Accumulator, Timer 1:

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 02F Hex (devices with

64 bytes of RAM), or initialized to

RAM address 06F Hex (devices with

128 bytes of RAM). B and X Pointers:

UNAFFECTED after RESET with power

already applied

RANDOM after RESET at power-on RAM:

UNAFFECTED after RESET with power already

applied

RANDOM after RESET at power-on WATCHDOG (if enabled):

The device comes out of reset with both the WATCHDOG logic and the Clock Monitor detector armed, with the WATCHDOG service window bits set and the Clock Monitor bit set. The WATCHDOG and Clock Monitor circuits are inhibited during reset. The WATCHDOG service window bits being initialized high default to the maximum WATCHDOG service window of 64k t

clock cycles. The Clock Monitor bit being initialized high will cause a Clock Monitor error following reset if the clock has not reached the minimum specified

frequency at the termination of reset. A Clock Monitor error will cause an active low error output on pin G1. This error output will continue until 16 t

–32 tCclock cycles following the clock frequency reaching the minimum specified value, at which time the G1 output will go high.

6.7.1 External Reset

The RESET input whenpulled lowinitializes thedevice. 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 mustensure thatthe RESET pin is heldlow 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 rise time or 15 µs whichever is greater,is recommended. Reset should also be wide enough to ensure crystal start-up upon Power-Up.

RESET may also be used to cause an exit from the HALT mode.

Arecommended reset circuit for this devicedis shown in

Fig-

ure 9

6.7.2 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-chipreset

circuitry is able to detect both fast and slow rise times on V

(VCCrise time between 10 ns and 50 ms). Under no circumstances should the RESET pin be allowed

to float. If the on-chip Power-On Reset feature isbeing used, RESET pin should be connected directly to V

. The output of the power-on reset detector will always preset the Idle timer to 0FFF(4096 t

). At this time, the internal reset will be

generated. If the Power-On Reset feature is enabled, the internal reset

will not be turned offuntil the Idle timer underflows. The internal reset will perform the same functions as external reset. The user is responsible for ensuring that V

is at the mini-

mum level for the operating frequencywithin the 4096t

. After the underflow, the logic is designed such that no additional internal resets occur as long as V

remains above

2.0V.

Note: While the POR feature of the COP8SAx was never intended to function

as a brownout detector, there are certainconstraints of this block that the system designer must address to properly recover from a brownout condition. This is true regardless of whether the internal POR or the external reset feature is used.

A brownout condition is reached when V

of the device goes below the minimum operating conditions of the device. The minimum guaranteed operating conditions are defined as V

= 4.5V@10 MHz CKI,

= 2.7V@4 MHz, or VCC= 2.0V during HALT mode (or when CKI

is stopped) operation. When using either the external reset or the POR feature to recover

from a brownout condition, V

must be lowered to 0.25V or an external reset must be applied whenever it goes below the minimumoperating conditions as stated above.

DS012838-13

FIGURE 8. Reset Logic

DS012838-14

RC>5x power supply rise time or 15 µs, whichever is greater.

FIGURE 9. Reset Circuit Using External Reset

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6.0 Functional Description (Continued)

The contents of data registers and RAM are unknown following the on-chip reset.

6.8 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. The oscillator feature is selectedby programming theECON register, which is summarized in

Table 2

TABLE 2. Oscillator Option

ECON4 ECON3 Oscillator Option

0 0 External Oscillator 1 0 Crystal Oscillator without Bias Resistor 0 1 R/C Oscillator 1 1 Crystal Oscillator with Bias Resistor

6.8.1 Crystal Oscillator

The crystal Oscillator 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).

Table3

shows the component values required for various standard crystal values. Resistor R2 is only used when the on-chip bias resistor is disabled.

Figure

shows the crystal oscillator connection diagram.

TABLE 3. Crystal Oscillator Configuration,

25˚C, V

R1 (kΩ)R2(MΩ) C1 (pF) C2 (pF) CKI Freq. (MHz)

0 1 30 30 15 0 1 32 32 10 0 1 45 30–36 4

5.6 1 100 100–156 0.455

6.8.2 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 specified duty cycle, rise andfall times,and input levels.G7/ CKO is available as a general purpose input G7 and/or Halt control.

Figure 13

shows the external oscillator connection

diagram.

6.8.3 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 HALTcontrol. 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 R/C oscillator to external noise can be improved by connecting one half the external capacitance to V

and one half to GND. PC board trace length on the CKI pin should be kept as short as possible.

Table 4

shows the oscillator frequency as a

function of external capacitance on the CKI pin.

Figure 14

shows the R/C oscillator configuration.

TABLE 4. R/C Oscillator Configuration,

−40˚C to +85˚C, V

4.5V to 5.5V,

OSC Freq. Variation of

External Capacitor R/C OSC Freq Instr. Cycle

(pF) (MHz) (µs)

0 5 2.0 9 4 2.5

52 2 5.0 150 1 10 TBD 32 kHz 312.5

DS012838-15

FIGURE 10. Reset Timing (Power-On Reset Enabled)

with V

Tied to RESET

DS012838-16

FIGURE 11. Reset Circuit Using Power-On Reset

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