UPD784938 Datasheet, PDF (364/733 Pages) NEC – 16-Bit Single-Chip Microcontrollers

CHAPTER 11 TIMER/EVENT COUNTER 2
11.9.6 Operation as external event counter
An external event counter counts clock pulses (CI pin input pulses) input from off-chip.
As shown in Figure 11-54, the value of timer counter 2 (TM2) is incremented in synchronization with a CI pin input valid
edge (specified as rising edge only).
Figure 11-54. External Event Counter Operation (single edge)
CI pin input
TM2
n
n+1
n+2
Remark The TM2 value is one less than the number of input clock pulses.
The control register settings when TM2 operates as an external event counter are shown in Figure 11-55, and the setting
procedure in Figure 11-56.
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Preliminary User’s Manual U13987EJ1V0UM00