M16C/62P Group (M16C/62P, M16C/62PT)
24.8 Timers
24.8.1 Timer A
24.8.1.1 Timer A (Timer Mode)
The timer remains idle after reset. Set the mode, count source, counter value, etc. using the TAiMR (i
= 0 to 4) register and the TAi register before setting the TAiS bit in the TABSR register to "1" (count
starts).
Always make sure the TAiMR register is modified while the TAiS bit remains "0" (count stops) regard-
less whether after reset or not.
While counting is in progress, the counter value can be read out at any time by reading the TAi
register. However, if the counter is read at the same time it is reloaded, the value "FFFFh" is read.
Also, if the counter is read before it starts counting after a value is set in the TAi register while not
counting, the set value is read.
If a low-level signal is applied to the NMI pin when the IVPCR1 bit in the TB2SC register = 1 (three-
phase output forcible cutoff by input on NMI pin enabled), the TA1OUT, TA2OUT and TA4OUT pins
go to a high-impedance state.
R
e
. v
2
3 .
0
S
e
p
0
, 1
2
0
0
4
R
E
J
0
9
B
0
1
8
5
0 -
2
3
0
Z
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f o
3
6
4
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24. Usage Precaution