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CHAPTER 8 16-BIT TIMER/EVENT COUNTER
User’s Manual U12697EJ3V0UM
(7) Trigger for one-shot pulse
The software trigger (bit 6 (OSPT) of 16-bit timer output control register 0 (TOC0) = 1) and the external trigger
(TI00 input) are always valid in one-shot pulse output mode.
If the software trigger is used in one-shot pulse output mode, the TI00 pin cannot be used as a general-purpose
port pin. Therefore, fix the TI00 pin to either high level or low level.
(8) Re-triggering one-shot pulse
(a) One-shot pulse output by software
When a one-shot pulse is output, do not set OSPT to 1. Do not output the one-shot pulse again until INTTM00,
which occurs on match between TM0 and CR00, occurs.
(b) One-shot pulse output with external trigger
If the external trigger is generated while the one-shot pulse is being output, the counter is cleared and
restarted, and the one-shot pulse is output again.
(9) Operation of OVF0 flag
The OVF0 flag is set to 1 in the following case:
Select mode in which 16-bit timer/event counter is cleared and started on match between TM0 and CR00
↓
Set CR00 to FFFFH.
↓
When TM0 counts up from FFFFH to 0000H
Figure 8-32. Operation Timing of OVF0 Flag
FFFFH
FFFEH
FFFFH
0000H
0001H
Count pulse
CR00
TM0
OVF0
INTTM00
