W78E365 Datasheet, PDF (17/40 Pages) Winbond – 8-BIT MICROCONTROLLER

W78E365
PWM4 Register
Bit:
7
6
5
4
3
2
1
0
Mnemonic: PWM4
PWM Control 2 Register
Bit:
7
-
6
5
4
-
-
-
Mnemonic: PWMCON2
PWM4OE: Output enable for PWM4
ENPWM: Enable for PWM4
Address: CFH
3
2
1
-
PWM4OE
-
Address: CEH
0
ENWPM4
6.8 Watchdog Timer
The Watchdog timer is a free-running timer which can be programmed by the user to serve as a
system monitor, a time-base generator or an event timer. It is basically a set of dividers that divide the
system clock. The divider output is selectable and determines the time-out interval. When the time-out
occurs, a system reset can also be caused if it is enabled. The main use of the Watchdog timer is as a
system monitor. This is important in real-time control applications. In case of power glitches or electro-
magnetic interference, the processor may begin to execute errant code. If this is left unchecked the
entire system may crash. The watchdog time-out selection will result in different time-out values
depending on the clock speed. The Watchdog timer will de disabled on reset. In general, software
should restart the Watchdog timer to put it into a known state. The control bits that support the
Watchdog timer are discussed below.
Watchdog Timer Control Register
Bit:
7
6
5
4
ENW CLRW WIDL
-
3
2
1
0
-
PS2 PS1 PS0
Mnemonic: WDTC
Address: 8FH
ENW : Enable watch-dog if set.
CLRW : Clear watch-dog timer and prescaler if set. This flag will be cleared automatically
WIDL : If this bit is set, watch-dog is enabled under IDLE mode. If cleared, watch-dog is disabled
under IDLE mode. Default is cleared.
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Publication Release Date: April 20, 2005
Revision A5