NEC UPD789426 Series User Manual page 121

16-bit timer mode control register 90
(TMC90)
TOF90 CPT901 CPT900 TOC90 TCL901TCL900 TOE90
2
f /2
X
6
f /2
f
X
X
7
f /2
X
f
XT
Synchronization
circuit
CPT90/INTP0
/P30
Edge detector
Figure 6-1. Block Diagram of 16-Bit Timer 90
Internal bus
16-bit compare register
90 (CR90)
Match
16-bit timer counter 90
(TM90)
16-bit counter
16-bit capture register
read buffer
90 (TCP90)
Write controller Write controller
f /2
X
Internal bus
TOD90
F/F
OVF
3
BCS902 BCS901 BCS900 BZOE90
Buzzer output control
register (BZC90)
CPU clock
P26
PM26
Output latch
TO90/P26
INTTM90
BZO90/P21
P21
PM21
Output latch