Hitachi H8S/2646 Hardware Manual page 411

Contention between TGR Write and Compare Match: If a compare match occurs in the T2
state of a TGR write cycle, the TGR write takes precedence and the compare match signal is
inhibited. A compare match does not occur even if the same value as before is written.
Figure 10-51 shows the timing in this case.
ø
Address
Write signal
Compare
match signal
TCNT
TGR
Figure 10-51 Contention between TGR Write and Compare Match
TGR write cycle
T1 T2
TGR address
N N+1
N
TGR write data
Inhibited
M
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