Contention Between Compare Matches A And B; 8Tcnt Operation At Internal Clock Source Switchover - Hitachi H8/3006 Hardware Manual

10.7.8

Contention between Compare Matches A and B

If compare matches A and B occur at the same time, the 8-bit timer operates according to the
relative priority of the output states set for compare match A and compare match B, as shown in
Table 10.5.
Table 10.5 Timer Output Priority Order
Output Setting
Toggle output
1 output
0 output
No change
10.7.9

8TCNT Operation at Internal Clock Source Switchover

Switching internal clock sources may cause 8TCNT to increment, depending on the switchover
timing. Table 10.6 shows the relation between the time of the switchover (by writing to bits CKS1
and CKS0) and the operation of 8TCNT.
The 8TCNT input clock is generated from the internal clock source by detecting the rising edge of
the internal clock. If a switchover is made from a low clock source to a high clock source, as in
case No. 3 in Table 10.6, the switchover will be regarded as a falling edge, a 8TCNT clock pulse
will be generated, and 8TCNT will be incremented.
8TCNT may also be incremented when switching between internal and external clocks.
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Priority
High
Low