EM73201
4-BIT MICRO-CONTROLLER FOR GENERAL PURPOSE PRODUCT
INTERNAL PULSE-RATE SELECTION
IPSA
0 0
Function description
10
XIN/2 Hz
14
0 1
1 0
1 1
XIN/2 Hz
18
XIN/2 Hz
22
XIN/2 Hz
TIMER/COUNTER FUNCTION
EVENT COUNTER MODE
For event counter mode, timer/counter increases one at any rising edge of P8.3/TRGA for timerA. When
timerA counts overflow, it will give interrupt control an interrupt request TOFIA.
P8.3/TRGA
TimerA value
n
n+1
n+2
n+3
n+4
n+5
n+6
PROGRAM EXAMPLE: Enable timerA with P28.
LDIA #0100B;
OUTA P28; Enable timerA with event counter mode
TIMER MODE
For timer mode ,timer/counter increase one at any rising edge of internal pulse . User can choose 4 kinds
of internal pulse rate by setting IPSA for timerA.
When timer/counter counts overflow, TRGA will be generated to interrupt control unit.
Internal pulse
n
n+1
n+2
n+3
n+4
n+5
n+6
n+7
TimerA value
PROGRAM EXAMPLE: To generate TRGA interrupt request after 60 ms with system clock XlN=4MHz
LDIA #0100B;
EXAE; enable mask 2
EICIL 110111B; interrupt latch ←0, enable EI
LDIA #06H;
STATAL;
* This specification are subject to be changed without notice.
7.20.1999 14
ELAN [ ELAN MICROELECTRONICS CORP ]
