ICOP Technology ICOP-602X User Manual page 30

nop
mov al, 0c5h
out 23h, al
nop
nop
Read the value of a configuration register
For example, read INDEX 3Ch :
Unlock configuration register
mov al, 03ch
out 22h, al
nop
nop
in al, 23h
nop
nop
push ax
Lock configuration register
pop ax ;AL - result
Write data to configuration register
For example, write 0FFh to INDEX 3Bh :
Unlock configuration register
mov al, 03bh
out 22h, al
nop
nop
mov al, 0ffh
out 23h, al
nop
26 ICOP Embedded 386SX CPU ISA Half Size SBC User's Manual
nop
mov al, 000h
out 23h, al
nop
nop