NEC 78K0 User Manual page 254

8-bit timer H1
count clock
8-bit timer counter
H1 count value
CMP01
CMP11
TMHE1
INTTMH1
Carrier clock
<1> When TMHE1 = 1 is set, 8-bit timer H1 starts a count operation. At that time, the carrier clock is held at the
inactive level.
<2> When the count value of 8-bit timer counter H1 matches the CMP01 register value, 8-bit timer counter H1 is
cleared and the INTTMH1 signal is output.
<3> The CMP11 register can be rewritten during 8-bit timer H1 operation, however, the changed value (L) is
latched. The CMP11 register is changed when the count value of 8-bit timer counter H1 and the CMP11
register value before the change (M) match (<3>').
<4> When the count value of 8-bit timer counter H1 and the CMP11 register value before the change (M) match,
the INTTMH1 signal is output, the carrier signal is inverted, and 8-bit timer counter H1 is cleared to 00H.
<5> The timing at which the count value of 8-bit timer counter H1 and the CMP11 register value match again is
indicated by the value after the change (L).
254
CHAPTER 9 8-BIT TIMERS H0 AND H1
Figure 9-15. Carrier Generator Mode Operation Timing (3/3)
(c) Operation when CMP11 is changed
00H 01H N 00H 01H
<3>
M
<2>
<1>
User's Manual U15947EJ2V0UD
00H N
M
N
<3>'
L
M (L)
<4>
*
00H 01H L 00H
<5>