13

* This specification are subject to be changed without notice.

EM73201

4-BIT MICRO-CONTROLLER FOR GENERAL PURPOSE PRODUCT

Preliminary

7.20.1999

Port 28 3

2

1

0

TMSA IPSA

Initial state: 0000

TIMER/COUNTER MODE SELECTION

TMSA

Function description

0 0

Stop

0 1

Event counter mode

1 0

Timer mode

1 1

Pulse width measurement mode

INTERRUPT CONTROL

TRGA request

DATA BUS

P8.3/

TRGA

EVENT COUNTER CONTROL

TIMER CONTROL

internal clock

P28

12 BIT COUNTER

TMSA

IPSA

PULSE-WIDTH MEASUREMENT

CONTROL

TIMER / COUNTER ( TIMERA)

Timer/counters can support user three special functions:

1. Even counter

2. Timer.

3. Pulse-width measurement.

These three functions can be executed by timer/counter.

For timerA, the counter data is saved in timer register TAH, TAM, TAL, which user can set counter

initial value and read the counter value by W/B instruction "LDATAH (B,L), STATAH (B,L)".

The counter can be set initial value and send counter value to timer register. P28 is the command port

for timerA , user can choose different operation mode and different internal clock rate by setting the

port. When timer/counter overflow, it will generate a TRGA interrupt request to interrupt control unit.

TIMER/COUNTER CONTROL

P8.3/TRGA is the external timer inputs for timerA, it used in event counter and pulse-width

measurement mode.

Timer/counter command port: P28 is the command port for timer/counterA.