CHAPTER 7 TIMER/COUNTER FUNCTION
User’s Manual U13850EJ6V0UD
227
Figure 7-24. Timing of One-Shot Pulse Output Operation with Software Trigger
Count clock
TMn count
value
0000H
0001H
0000H
N + 1
N
M + 2
N
−
1
M
−
1
M + 1
N
M
CRn1 set
value
N
CRn0 set
value
M
OSPTn
INTTMn1
INTTMn0
TOn pin
output
Sets 0CH to TMCn
(TMn count starts)
N
M
N
M
N
M
Caution
16-bit timer register n starts operating as soon as TMCn2 and TMCn3 have been set to
values other than 0, 0 (operation stop mode).
Remark
n = 0, 1
N < M
(2) One-shot pulse output with 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
7-25, 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 the 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 at the count value (N) set in advance to 16-bit capture/compare register n1 (CRn1).
After that, the output is deasserted at the count value (M) set in advance to 16-bit capture/compare register n0
(CRn0)
Note
.
Note
This is an example when N < M. When N > M, the output is asserted by CRn0 and deasserted by
CRn1.
Caution
If an external trigger occurs while a one-shot pulse is being output, the 16-bit timer/event
counter is cleared and started and a one-shot pulse is output again.