18

* This specification are subject to be changed without notice.

8.11.2000

EM73C63

4-BIT MICRO-CONTROLLER FOR LCD PRODUCT

Preliminary

Internal pulse

TimerB (TimerA )value

n

n+1

n+2

n+3

n+4

n+5

n+6

n+7

P8.1/TRGB (P8.3/TRGA)

TimerB (TimerA) value n

n+1

n+2

n+3

n+4

n+5

n+6

TIMER/COUNTER FUNCTION

Timer/counterA,B are programmable for timer, event counter and pulse width measurement mode. Each

timer/counter can execute any of these functions independently.

EVENT COUNTER MODE

under event counter mode, the timer/counter is increased by one at any rising edge of P8.1/TRGB for timerB

(P8.3/TRGA for timer A). When timerB (timerA) counts overflow, it will provide an interrupt request

TRGB (TRGA) to interrupt control unit.

PROGRAM EXAMPLE: Enable timerA with P28

LDIA #0100b;

OUTA P28; Enable timerA with event counter mode

TIMER MODE

Under timer mode ,the timer/counter is increased by one at any rising edge of internal pulse . User can choose

up to 4 types of internal pulse rate by setting IPSB for timerB (IPSA for timerA).

When timer/counter counts overflow, An interrupt request will be sent to interrupt control unit.

PROGRAM EXAMPLE: To generate TRGA interrupt request after 60 ms with system clock LXlN=32KHz

LDIA #0100B;

EXAE;

enable mask 2

EICIL 110111b; interrupt latch

←0, enable EI

LDIA #0Ah;

STATAL;

LDIA #00h;

STATAM;

LDIA #0Fh;

STATAH;

LDIA #1000B;

NOTE:

The preset value of timer/counter register is calculated as following procedure.

The number of internal pulse to get timer overflow = 60 ms/ 0.244ms = 245.901= 0F6h

The preset value of timer/counter register = 1000h - 0F6h = F0Ah

PULSE WIDTH MEASUREMENT MODE