Acnodes PCH 3582 - Manual (Page 52)

outportb(0x4F, 0x08); //Select LDN=8, GPIO Port6
or
outportb(0x4E, 0x07); //LDN selection register
outportb(0x4F, 0x09); //Select LDN=9, GPIO Port2
Activate the logic device
Example x86 assembly code:
mov dx, 4Eh
mov al, 030h ;Logic device activation control reg.
out dx, al
mov dx, 4Fh
in al, dx
or al, 004h ;Set bit2 to enable GPIO Port6 if LDN=8
or al, 002h ;Set bit1 to enable GPIO Port2 if LDN=9
out dx, al
Example C code:
outportb(0x4E, 0x30); //Logic device activation control
outportb(0x4F, (inportb(0x4F)|0x2));
//Set bit[1] to enable GPIO Port2 if LDN=9
Or
outportb(0x4E, 0x30); //Logic device activation control
outportb(0x4F, (inportb(0x4F)|0x4));
//Set bit[2] to enable GPIO Port6 if LDN=8
Configure GPIO register
Example x86 assembly code:
mov dx, 4Eh
mov al, 0E6h ;GPIO inversion reg.
out dx, al
mov dx, 4Fh
mov al, 000h ;0
– normal, 1 - inverted
out dx, al
mov dx, 4Eh
mov al, 0E4h ;GPIO I/O selection reg.
out dx, al
mov dx, 4Fh
mov al, 0FFh ;0
– Output, 1 – Input
;or mov al, 0F0h to set output