w83977ctf Winbond Electronics Corp America, w83977ctf Datasheet - Page 126

• Manufacturer Part Number: w83977ctf
• Description: Winbond I/o
• Manufacturer: Winbond Electronics Corp America

Bit 2: Mouse interrupt reset Enable or Disable
CRF4 (WDT_CTRL1, Default 0x00)
*Note: 1). Internal logic provides an 1us Debounce Filter to reject the width of P20 pulse less than 1us.
Bit 0: Reserved.
Watch Dog Timer Control Register #1
Bit 7: Reserved
Bit 6:
Bit 5-4: Power LED toggle pulse frequency select
Bit 3: Enable the rising edge of Keyboard Reset(P20) to force Time-out event, R/W*
Bit 2: Force Watch Dog Timer Time-out, Write only*
Bit 1: Enable Power LED toggle pulse with 50% duty cycle , R/W
Bit 0: Watch Dog Timer Status, R/W
2). The P20 signal coming from Debounce Filter is ORed with the signal generated by the Force Time-out bit, and then
connects to set the Bit 0(Watch Dog Timer Status). The ORed signal is self-clearing.
= 1 Watch Dog Timer is reset upon a Mouse interrupt
= 0 Watch Dog Timer is not affected by Mouse interrupt
Bit 1: Keyboard interrupt reset Enable or Disable
= 1 Watch Dog Timer is reset upon a Keyboard interrupt
= 0 Watch Dog Timer is not affected by Keyboard interrupt
= 1 Watch Dog counter counts in seconds.
= 0 Watch Dog counter counts in minutes.
= 00 Power LED toggle pulse frequency is 1Hz
= 01 Power LED toggle pulse frequency is 1/2Hz
= 10 Power LED toggle pulse frequency is 1/4Hz
= 11 Power LED toggle pulse frequency is 1/8Hz
= 1 Enable
= 0 Disable
= 1 Force Watch Dog Timer time-out event; this bit is self-clearing.
= 1 Enable
= 0 Disable
= 1 Watch Dog Timer time-out occurred.
= 0 Watch Dog Timer counting
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Publication Release Date: March 1999
W83977EF/ CTF
PRELIMINARY
Revision A1