Acnodes PCH 3582 - Manual (Page 56)

//Start the super I/O chip programming
ENTERPRG
//Select the logical device 9, GP2
SELETDEV(9)
//Read GPIO Value
outportb(INDEXP, 0xE5);
cGP2 = inportb(DATAP);
cGP2 = cGP2 & 0xF;
//Exit the super I/O chip programming
EXITPRG
return cGP2;
}
//Write GPIO Port6
int WriteGP6(unsigned char cGP6) {
//Start the super I/O chip programming
ENTERPRG
//Select the logical device 8, GP6
SELETDEV(8)
//Write GP1 value
WRITEREG(0xE5, cGP6)
//Exit the super I/O chip programming
EXITPRG
return 0;
}
int main() {
unsigned char cGP;
//Initialize the GPIO port
InitGP2();