
CHAPTER 6 16-BIT TIMER/EVENT COUNTER 00
User’s Manual U16315EJ3V1UD
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Cautions 1. When the internal oscillation clock is selected as the clock to be supplied to the CPU, the
clock of the internal oscillator is divided and supplied as the count clock. If the count clock
is the internal oscillation clock, the operation of 16-bit timer/event counter 00 is not
guaranteed.
When an external clock is used and when the internal oscillation clock is
selected and supplied to the CPU, the operation of 16-bit timer/event counter 00 is not
guaranteed, either, because the internal oscillation clock is supplied as the sampling clock to
eliminate noise.
2. Always set data to PRM00 after stopping the timer operation.
3. If the valid edge of TI000 is to be set for the count clock, do not set the clear & start mode
using the valid edge of TI000 and the capture trigger.
4. If the TI000 or TI010 pin is high level immediately after system reset, the rising edge is
immediately detected after the rising edge or both the rising and falling edges are set as the
valid edge(s) of the TI000 pin or TI010 pin to enable the operation of 16-bit timer counter 00
(TM00). Care is therefore required when pulling up the TI000 or TI010 pin. However, if the
TI000 pin or TI010 pin is high level when re-enabling operation after the operation has been
stopped, the rising edge is not detected.
5. When P01 is used as the valid edge input pin of TI010, it cannot be used as the timer output
(TO00), and when used as TO00, it cannot be used as the valid edge input pin of TI010.
(5) Port mode register 0 (PM0)
This register sets port 0 input/output in 1-bit units.
When using the P01/TO00/TI010 pin for timer output, clear PM01 and the output latch of P01 to 0.
When using the P01/TO00/TI010 pin for timer input, set PM01 to 1. At this time, the output latch of P01 may be 0
or 1.
PM0 can be set by a 1-bit or 8-bit memory manipulation instruction.
RESET input sets PM0 to FFH.
Figure 6-9. Format of Port Mode Register 0 (PM0)
7
1
6
1
5
1
4
1
3
PM03
2
PM02
1
PM01
0
PM00
Symbol
PM0
Address: FF20H
After reset: FFH
R/W
PM0n
0
1
P0n pin I/O mode selection (n = 0 to 3)
Output mode (output buffer on)
Input mode (output buffer off)