CHAPTER 8 TIMER/COUNTER FUNCTION
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User’s Manual U15109EJ3V0UD
Figure 8-24. Timing of One-Shot Pulse Output Operation via Software Trigger
&
'
'
'
,
,%
−
−
,
CRn1 set
value
&
!0
INTTMn0
!
'
Caution
16-bit timer register n starts operating as soon as TMCn2 and TMCn3 are set to values other
than 0, 0 (operation stop mode).
Remark
n = 0, 1, 7 to 12
N < M
(2) One-shot pulse output via external trigger
A one-shot pulse can be output from the TOn pin by setting 16-bit timer mode control register n (TMCn),
capture/compare control register n (CRCn), and 16-bit timer output control register n (TOCn) as shown in Figure
8-25, and by using the valid edge of the TIn0 pin as an external trigger.
The valid edge of the TIn0 pin is specified by bits 4 and 5 (ESn00 and ESn01) of prescaler mode register n0
(PRMn0). The rising, falling, or both rising and falling edges can be specified.
When the valid edge of the TIn0 pin is detected, the 16-bit timer/event counter is cleared and started, and the
output is asserted active at the count value (N) preset to 16-bit capture/compare register n1 (CRn1).
After that, the output is deasserted inactive at the count value (M) preset to 16-bit capture/compare register n0
(CRn0)
490
.
Note
This is an example when N < M. When N > M, the output becomes active at the CRn0 value and inactive
at the CRn1 value.
Caution
If the external trigger occurs while a one-shot pulse is being output, the 16-bit timer/counter
clears & starts and the one-shot pulse is output again.
Remark
n = 0, 1, 7 to 12