FUJITSU F2MCTM-16LX - Manual (Page 218)

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CHAPTER 12 WATCHDOG TIMER
12.3.1 Watchdog timer control register (WDTC)
The watchdog timer control register starts and clears the watchdog timer, sets the
interval time, and holds reset factors.
■ Watchdog Timer Control Register (WDTC)
Figure 12.3-2 Watchdog Timer Control Register (WDTC)
4 5 3 2 1 6
R R R R W W W
0 7
XXXXX111 B
PONR WRST ERST SRST WTE WT1 WT0
HCLK: Oscillation clock
The parenthesized values are interval time when the oscillation clock
operates at HCLK 4 MHz.
bit1 bit0
WT1 WT0 Interval time select bit (timebase timer output select)
Interval time Clock cycle
Min Max
0 0 approx. 3.58 ms approx. 4.61 ms 2 14 ± 2 11 /HCLK
0 1 approx. 14.33 ms approx. 18.3 ms 2 16 ± 2 13 /HCLK
1 0 approx. 57.23 ms approx. 73.73 ms 2 18 ± 2 15 /HCLK
1 1 approx. 458.75 ms approx. 589.82 ms 2 21 ± 2 18 /HCLK
Reset value
bit2
WTE Watchdog timer control bit
0 First programming after reset:
Start up the watchdog timer
Twice or more programming after reset :
Clear the watchdog timer
1 No effect
SCLK: Sub clock*
2
The parenthesized values are interval time when the oscillation clock
bit1 bit0
WT1 WT0 Interval time select bit (watch timer output select)
Interval time Clock cycle
Min Max
0 0 approx. 0.457 s approx. 0.576 s
2
12 ± 2
9
/SCLK
0 1 approx. 3.584 s approx. 4.608 s
2
15 ± 2
12
/SCLK
1 0 approx. 7.168 s approx. 9.216 s
2 16 ± 2 13 /SCLK
1 1 approx. 14.336 s approx. 18.432 s
2 17 ± 2 14 /SCLK
bit7 bit5 bit4 bit3
Reset factor bit Reset factor
PONR WRST ERST SRST
1 X X X Power-on reset
* 1 1 * 1 * 1 Watchdog reset
* 1 * 1 1 * 1 External reset (Low level input to RST pin)
* 1 * 1 * 1 1 Software reset (write "1" to RST bit)
R : Read only
W : Write only
X : Undefined
*1 : The previous state is held.
*2 : However, SCLK is 2 division or 4 division of the clock inputted to the low-speed oscillation pin (X0A and
X1A) or internal CR oscillation clock. The division ratio is set by the SCDS bit of the PLL/subclock control
register (PSCCR). (See "CHAPTER 5 CLOCKS".)
See Table 12.1-1 for the interval time.
Address
0000A8
H