AAEON PCM-QM77 - Manual (Page 168)

C o m p a c t B o a r d P C M - Q M 7 7
Appendix E Digital I/O F-5
begin:
mov cl,01h
mov al,80h
call CT_I2CWriteByte
call Delay5ms
mov al,00h
mov cl,20h
call CT_I2CWriteByte
mov cl,22h
call CT_I2CReadByte
;Input : CL - register index
; CH - device ID
;Output : AL - Value read
Ct_I2CReadByte Proc Near
mov ch,06eh
mov dx, 0f040h + 00h ; Host Control Register
mov al, 0ffh ; Clear previous
commands
out dx, al