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2 block diagram of watch timer, Block diagram of watch timer – FUJITSU F2MCTM-16LX User Manual

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CHAPTER 15 WATCH TIMER

15.2

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 15.2-1 Block Diagram of Watch Timer

The actual interrupt request number of the watch timer is as follows:

Interrupt request number: #27(1B

H

)

Watch timer counter

The watch timer counter is a 15-bit up counter that uses the subclock (SCLK) as a count clock.

Counter clear circuit

The counter-clear circuit clears the watch timer counter.

WTOF WTR

WTC1 WTC0

WTC2

WDCS SCE WTIE

Ч

2

5

Ч

2

4

Ч

2

3

Ч

2

1

Ч

2

9

Ч

2

10

Ч

2

11

Ч

2

12

Ч

2

13

Ч

2

14

Ч

2

15

Ч

2

8

Ч

2

7

Ч

2

6

Ч

2

2

SCLK

OF

OF

OF

OF

OF

OF

OF

OF

To watchdog
timer

Watch timer counter

Power-on reset

Transits to hardware standby

Transits to stop mode

Counter

clear circuit

Interval timer

selector

To subclock oscillation
stabilization wait time

Watch timer interrupt

OF

: Overflow

SCLK : Subclock

Watch timer control register (WTC)