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Caution – FUJITSU MB91460 SERIES FR60 User Manual

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Chapter 37 Output Compare

8.Caution

8. Caution

• Compare stop space during compare operation

As shown below, for one count directly after the compare value is written to the compare register, the
compare operation cannot be used.

• When CMOD=“1” and OCCP0=OCCP1 setting, if a compare match is generated, the port will only reverse

once.

• Compare registers (OCCP0 - OCCP7) are set to the initial values. Always set a value before activating

them.

• When specifying the output level of compare pins (OCU0 - OCU7), first stop the compare operation.

• Output compare is synchronous with the free-run timer, so if you stop the free-run timer the compare

operation also stops.

• Even when reversal mode specification (CMOD) is set to “1” and the compare operation is in cooperative

mode, interrupts are generated independently.

• When using an external clock as the free-run timer, compare-matches and interrupts are generated with the

following clock. To generate compare match output and interrupts, at least “1 clock division” must be input to
the external clock free-run timer after the compare-match.

N-2

N-1

N

N+1

N+2

N+3

X

N

Write to compare register

Compare

timing

Compare stop space
In this case, a match signal
will not be generated!

N-2

N-1

N

N+1

N+2

N+3

X

N

Free-run timer count value

Compare register value