CHAPTER 7 8-BIT TIMER/EVENT COUNTER
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User’s Manual U11302EJ4V0UM
(2) External event counter operation
The external event counter counts the number of external clock pulses input to the TI1/P33 and TI2/P34
pins using 8-bit timer registers 1 and 2 (TM1 and TM2).
TM1 and TM2 are incremented each time the valid edge specified by timer clock select register 1 (TCL1)
is input. Either the rising or falling edge can be selected.
When the TM1 and TM2 count values match the values of the 8-bit compare registers (CR10 and CR20),
TM1 and TM2 are cleared to 0 and interrupt request signals (INTTM1 and INTTM2) are generated.
Figure 7-9. External Event Counter Operation Timing (with Rising Edge Specified)
Remark
N = 00H to FFH
TI1 pin input
TM1 count value
CR10
INTTM1
00
01
02
03
04
05
N – 1
N
N
00
01
02
03