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CHAPTER 8 16-BIT TIMER/EVENT COUNTERS 00, 01
User
’
s Manual U14260EJ3V1UD
Figure 8-13. Format of Prescaler Mode Register 01 (PRM01)
Address: FF65H After reset: 00H R/W
Symbol
7
6
5
4
3
2
1
0
PRM01
ES111
ES101
ES011
ES001
0
0
PRM011
PRM001
ES111
ES101
TI011 pin valid edge selection
0
0
Falling edge
0
1
Rising edge
1
0
Setting prohibited
1
1
Both falling and rising edges
ES011
ES001
TI001 pin valid edge selection
0
0
Falling edge
0
1
Rising edge
1
0
Setting prohibited
1
1
Both falling and rising edges
PRM011
PRM001
Count clock selection
f
X
= 8.38 MHz
f
X
= 12 MHz
Note 1
0
0
f
X
/2
4.19 MHz
6 MHz
0
1
f
X
/2
3
1.04 MHz
1.5 MHz
1
0
f
X
/2
9
16.36 kHz
23.43 kHz
1
1
TI001 pin valid edge
Notes 2, 3
Notes 1.
Expanded-specification products of
μ
PD780078 Subseries only.
2.
The external clock requires a pulse two cycles longer than internal clock (f
X
/2
3
).
3.
When the valid edge of the TI001 pin is selected, the main system clock is used as the sampling clock
for noise elimination. The valid edge of the TI001 pin can be used only when the main system clock
is operating.
Cautions 1. Always set data to PRM01 after stopping the timer operation.
2. If the valid edge of the TI001 pin is to be set as the count clock, do not set the clear & start
mode and the capture trigger at the valid edge of the TI001 pin.
3. When P75 is used as the valid edge of the TI001 pin, it cannot be used as the timer output
(TO01 pin), and when used as the TO01 pin, it cannot be used as the valid edge of the TI001
pin.
4. If the TI001 or TI011 pin is high level immediately after system reset, the rising edge is
immediately detected after the rising edge or both the rising and falling edge are set as the
valid edge(s) of the TI001 pin or TI011 pin to enable the operation of 16-bit timer counter
01 (TM01). Be careful when pulling up the TI001 pin or the TI011 pin. However, when re-
enabling operation after the operation has been stopped once, the rising edge is not
detected.
Remarks 1.
f
X
: Main system clock oscillation frequency
2.
TI001 or TI011 pin: 16-bit timer/event counter 01 input pin