MITX-6922 Mini-ITX Motherboard Based on Intel QM67/QM77 Chipset
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Appendix
Appendix 1:Watchdog Programming Guide
Watchdog reference code(ASM)
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Set the port to realize watchdog function. Different functions of Watchdog Timer can be
realized by writing data to corresponding ports and operating ports.
void main()
{
intindexp = 0x2e,datap = 0x2f;
unsigned char temp;
outportb(indexp,0x87);
outportb(indexp,0x01); //unlock
outportb(indexp,0x55);
outportb(indexp,0x55);
outportb(indexp,0x07);
outportb(datap,0x07);
outportb(indexp,0x71);
outportb(datap,0x80); //enable logical device
outportb(indexp,0x72);
outportb(datap,0xc0); //set second
/*outportb(datap,0x40); set minute*/
outportb(indexp,0x73);
outportb(datap,0x03); //set 3 seconds
outportb(indexp,0x74);
outportb(datap,0x00);
outportb(indexp,0x02);
temp = (unsigned char)inportb(datap);