NEC uPD78P078 - Manual (Page 268)

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CHAPTER 10 8-BIT TIMER/EVENT COUNTERS 5 AND 6
Count Pulse
CR50, CR60 N
X X – 1 FFH 00H 01H
M
02H TM5, TM6 Count Value
(3) Operation after compare register change during timer count operation
If the values after the 8-bit compare registers (CR50 and CR60) are changed are smaller than those of 8-
bit timer registers (TM5 and TM6), TM5 and TM6 continue counting, overflow and then restarts counting from
0. Thus, if the value (M) after CR50 and CR60 change is smaller than that (N) before change it is necessary
to restart the timer after changing CR50 and CR60.
Figure 10-21. Timings after Compare Register Change during Timer Count Operation
Remark N > X > M