Cautions For 8-Bit Timer/Event Counters 50 And 51 - NEC 78K0 User Manual

7.5 Cautions for 8-Bit Timer/Event Counters 50 and 51

(1) Timer start error
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 8-bit timer counters 50 and 51 (TM50, TM51) are started asynchronously to the count clock.
TM5n count value
Remark n = 0, 1
CHAPTER 7 8-BIT TIMER/EVENT COUNTERS 50 AND 51
Figure 7-16. 8-Bit Timer Counter 5n Start Timing
Count clock
00H
Timer start
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