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Cycle of clock supply – FUJITSU F2MCTM-16LX User Manual

Page 285

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CHAPTER 15 WATCH TIMER

Cycle of Clock Supply

The watch timer supplies an operation clock to the oscillation stabilization wait time timer of the subclock

and the watchdog timer. Table 15.1-2 shows the cycles of clocks supplied from the watch timer.

Note:

The frequency of the subclock (SCLK) is a value for 2 division/4 division of the clock inputted to the
low-speed oscillation pin (X0A and X1A) or the internal CR oscillation clock.
The division ratio is set by the SCDS bit of the PLL/subclock control register (PSCCR).
When using the internal CR oscillation clock, see "CHAPTER 6 CLOCK SUPERVISOR". Please con-
sider the frequency difference of built-in CR oscillation when you use built-in CR oscillation clock as a
sub-clock.

Table 15.1-2 Cycle of Clock Supplied from Watch Timer

Where to Supply Clock

Clock Cycle

Timer for oscillation stabilization wait time of subclock

2

14

/SCLK(4.000 s)

Watchdog timer

2

10

/SCLK(125 ms)

2

13

/SCLK(1.000 s)

2

14

/SCLK(2.000 s)

2

15

/SCLK(4.000 s)

SCLK: Subclock frequency
The parenthesized values are provided when the subclock operates at 8.192 kHz.