EM73P982 datasheet(16/41 Pages) EMC

16 / 41 page

* This specification are subject to be changed without notice.

EM73P982

4-BIT MICROCONTROLLER

12.25.2001

TIME BASE INTERRUPT (TBI )

The time base can be used to generate a fixed frequency interrupt. There are 8 kinds of frequencies can be

selected by setting "P25"

Single clock mode

P25

( initial value 0000 )

0 0 x x: Interrupt disable

0 1 0 0: Interrupt frequency XIN / 210 Hz

0 1 0 1: Interrupt frequency XIN / 211 Hz

0 1 1 0: Interrupt frequency XIN / 212 Hz

0 1 1 1: Interrupt frequency XIN / 213 Hz

1 1 0 0: Interrupt frequency XIN / 29 Hz

1 1 0 1: Interrupt frequency XIN / 28 Hz

1 1 1 0: Interrupt frequency XIN / 215 Hz

1 1 1 1: Interrupt frequency XIN / 217 Hz

1 0 x x: Reserved

TIMER / COUNTER ( TIMERA, TIMERB)

Timer/counters can support user three special functions:

1. Even counter

2. Timer.

3. Pulse-width measurement.

These three functions can be executed by 2 timer/counter independently.

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 instruction "LDATAH(M,L), STATAH(M,L)" and timer register is

TBH, TBM, TBL and W/R instruction "LDATBH (M,L), STATBH (M,L)".

The basic structure of timer/counter is composed by two same structure counter, these two counters can be

set initial value and send counter value to timer register, P28 and P29 are the command ports for timerA

and timer B, user can choose different operation mode and different internal clock rate by setting these two

ports. When timer/counter overflow, it will generate a TRGA(B) interrupt request to interrupt control unit.

To access TA, TB, user must switch RAM at bank0.

EM73P982 Datasheet(PDF) 16 Page - ELAN Microelectronics Corp