Timing Of Interval Timer Operation With 16-Bit Resolution - NEC PD789488 User Manual

t
Count clock
TM60 count value 00H N
CR60 N N
TCE60
Count start
TM50 count pulse
TM50 00H
X
CR50
INTTM60
Interrupt not generated because
TM50 does not match
TO60
Interval time = (256X + N + 1) × t: X = 00H to FFH, N = 00H to FFH
Remark
Figure 7-19. Timing of Interval Timer Operation with 16-Bit Resolution
7FH 80H FFH 00H
Not cleared because TM50 does not match
N N
01H
7FH 80H FFH 00H N
N
N
X − 1
X
X
X
00H 7FH 80H FFH 00H
Cleared because TM50 and TM60 match simultaneously
N
N N
X − 1
00H
Interrupt acknowledgement Interrupt acknowledgement
Interval time
N
00H
N
X 00H