APPENDIX D LIST OF CAUTIONS
User’s Manual U18172EJ2V0UD
312
(5/15)
Chapter
Cl
assi
fi
cati
on
Function Details
of
Function
Cautions Page
Hard
PRM00:
Prescaler mode
register 00
When using P21 as the input pin (TI010) of the valid edge, it cannot be used as a
timer output (TO00). When using P21 as the timer output pin (TO00), it cannot be
used as the input pin (TI010) of the valid edge.
pp. 91,
120
Interval timer
Changing the CR000 setting during TM00 operation may cause a malfunction. To
change the setting, refer to 6.5 Cautions Related to 16-Bit Timer/Event Counter
00 (17) Changing compare register during timer operation.
p. 92
External event
counter
When reading the external event counter count value, TM00 should be read.
pp. 96,
120
To use two capture registers, set the TI000 and TI010 pins.
pp. 97,
118
pp. 97,
Pulse width
measurement
The measurable pulse width in this operation example is up to 1 cycle of the timer
counter.
99, 101,
103
Square-wave
output
Changing the CR000 setting during TM00 operation may cause a malfunction. To
change the setting, refer to 6.5 Cautions Related to 16-Bit Timer/Event Counter
00 (17) Changing compare register during timer operation.
p. 105
Changing the CRC0n0 setting during TM00 operation may cause a malfunction.
To change the setting, refer to 6.5 Cautions Related to 16-Bit Timer/Event
Counter 00 (17) Changing compare register during timer operation.
p. 107
Values in the following range should be set in CR000 and CR010.
0000H < CR010 < CR000
≤
FFFFH
pp. 108,
120
PPG output
The cycle of the pulse generated through PPG output (CR000 setting value + 1)
has a duty of (CR010 setting value + 1)/(CR000 setting value + 1).
pp. 108,
120
Soft
Do not set the OSPT00 bit to 1 again
while the one-shot pulse is being output. To
output the one-shot pulse again, wait until the current one-shot pulse output is
completed.
pp. 110,
116
Hard
When using the one-shot pulse output of 16-bit timer/event counter 00 with a
software trigger, do not change the level of the TI000 pin or its alternate-function
port pin. Because the external trigger is valid even in this case, the timer is
cleared and started even at the level of the TI000 pin or its alternate-function port
pin, resulting in the output of a pulse at an undesired timing.
pp. 110,
116
Do not set 0000H to the CR000 and CR010 registers.
pp. 111,
117
Soft
One-shot pulse
output: software
trigger
16-bit timer counter 00 starts operating as soon as a value other than 00
(operation stop mode) is set to the TMC003 and TMC002 bits.
pp. 112,
115
Hard
Do not input the external trigger again while the one-shot pulse is output. To
output the one-shot pulse again, wait until the current one-shot pulse output is
completed.
pp. 112,
117
Do not set the CR000 and CR010 registers to 0000H.
pp. 113,
117
Soft
One-shot pulse
output: external
trigger
16-bit timer counter 00 starts operating as soon as a value other than 00
(operation stop mode) is set to the TMC002 and TMC003 bits.
pp. 114,
115
Hard
Timer start
errors
An error of up to one clock may occur in the time required for a match signal to be
generated after timer start. This is because 16-bit timer counter 00 (TM00) is
started asynchronously to the count clock.
p. 115
Chapter 6
Soft
16-bit
timer/
event
counters
00
One-shot pulse
output
One-shot pulse output normally operates only in the free-running mode or in the
clear & start mode at the valid edge of the TI000 pin. Because an overflow does
not occur in the clear & start mode on a match between TM00 and CR000, one-
shot pulse output is not possible.
p. 116
