Fujitsu F2MC-16LX Series, Hardware Manual

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CHAPTER 9 Watch timer
9.2 Block Diagram of Watch Timer
The watch timer consists of the following blocks:
• Watch timer counter
• Counter clear circuit
• Interval timer selector
• Watch timer control register (WTC)
■
Block Diagram of Watch Timer
Figure 9.2-1 Block Diagram of Watch Timer
The actual interrupt request number of the watch timer is as follows:
Interrupt request number: #28 (1C
H
)
●
Watch timer counter
The watch timer counter is a 15-bit up counter that uses the sub clock (SCLK) as a count clock.
●
Counter clear circuit
The counter-clear circuit clears the watch timer counter.
Watch timer counter
To watchdog timer
Interval timer
selector
Counter
clear
circuit
Power-on reset
Stop mode transmission
Watch timer interrupt
WTOF WTR WTC1 WTC0 WTC2
WDCS SCE WTIE
2
5
2
4
2
3
2
1
2
9
2
10
2
11
2
12
2
13
2
14
2
15
2
8
2
7
2
6
2
2
SCLK
Hardware standby transmission
W a t c h t i m e r c o n t r o l r e g i s t e r ( WTC)
OF
OF
OF OF
OF
OF
OF
OF
To subclock
oscillation stabilization
waiting time
: Over flow OF
: Subclock SCLK