A.2 Watchdog programming
Watchdog: (Index Port:300H , Data Port:301) 1, Enable Watchdog
Outportb (0x4e,0x77);
Outportb (0x4e,0x77); //Entry Configuration Mode Outportb (0x4e,0x07); //Select Register Index 0x07 Outportb (0x4f,0x08); //Select LDN 8
Outportb (0x4e,0x30); //Select LDN 8 Register Index 0x30 Outportb (0x4f,0x01); //Enable Watchdog Timer Device Outportb (0x4e,0xaa); //Exit Configuration Mode
2, Set Watchdog Timer to 20 Second Used Base Address 0x300~0x301
Outportb (0x300,0x03); Select Unit to One Second and clear Time out Status
;If 0x03 Change to 0x00 that Unit is 10 mini Second
;Or if change to 0x05 that unit is one minute Outportb(0x301,0x14);
Outportb(0x301,0x14); //Set Timer to 20 Second and Enable Timer 3, Disable Watchdog
Outportb (0x4e,0x77);
Outportb (0x4e,0x77); //Entry Configuration Mode Outportb (0x4e,0x07); //Select Register Index 0x07 Outportb (0x4f,0x08); //Select LDN 8
Outportb (0x4e,0x30); //Select LDN 8 Register Index 0x30 Outportb (0x4f,0x00); //Disable Watchdog Timer Device Outportb (0x4e,0xaa); //Exit Configuration Mode
57 | AppendixA |
