UPD784938 Datasheet, PDF (365/733 Pages) NEC – 16-Bit Single-Chip Microcontrollers

CHAPTER 11 TIMER/EVENT COUNTER 2
Figure 11-55. Control Register Settings for External Event Counter Operation
(a) Prescaler mode register 1 (PRM1)
7
6
5
4
3
2
1
0
PRM1 1
1
1
1
0
×
×
×
External clock input (C1) specified
(b) External interrupt mode register 0 (INTM0)
7
6
5
4
3
2
1
0
INTM0 0
1
×
×
×
×
×
×
(c) Timer control register 1 (TMC1)
Rising edge specified as CI input
valid edge
7
6
5
4
3
2
1
0
TMC1 1
0
0
0
×
×
0
0
Normal mode
Overflow flag
Count operation enabled
Figure 11-56. External Event Counter Operation Setting Procedure
Event counter
Specify CI pin input valid edge
Set PRM1
PRM1 ← 0F×H
Start count
CE2 ← 1
; Set 1 in bit 7 of TMC1
Preliminary User’s Manual U13987EJ1V0UM00
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