CHAPTER 6 16-BIT TIMER/EVENT COUNTER 00
Preliminary User’s Manual U16846EJ1V0UD
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Cautions 1. When the Ring-OSC clock is selected as the clock to be supplied to the CPU, the clock of the
Ring-OSC oscillator is divided and supplied as the count clock. If the count clock is the
Ring-OSC clock, the operation of 16-bit timer/event counter 00 is not guaranteed. When an
external clock is used and when the Ring-OSC clock is selected and supplied to the CPU, the
operation of 16-bit timer/event counter 00 is not guaranteed, either, because the Ring-OSC
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 the TI000 pin is to be set for the count clock, do not set the clear & start
mode using the valid edge of the TI000 pin 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, when re-
enabling operation after the operation has been stopped once, the rising edge is not
detected.
5. When P01 is used as the TI010 valid edge input pin, it cannot be used as the timer output
(TO00), and when used as TO00, it cannot be used as the TI010 pin valid edge input pin.
Remarks 1. f
X
: High-speed system clock oscillation frequency
2. TI000, TI010: 16-bit timer/event counter 00 input pin
3. Figures in parentheses are for operation with f
X
= 10 MHz.
(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, set PM01 and the output latch of P01 to 0.
Clear PM01 to 0 to when using the P01/TO00/TI010 pin as a timer input pin. The output latch of P01 at this time
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)