APPENDIX
MB890 User’s Manual 57
; Name : Unlock_Chip
; IN : None
; OUT : None
;[]===============================================
Unlock_Chip Proc Near
Mov dx, 4Eh
mov al, 87h
out dx, al
out dx, al
ret
Unlock_Chip Endp
;[]================================================
; Name : Lock_Chip
; IN : None
; OUT : None
;[]================================================
Unlock_Chip Proc Near
mov dx, 4Eh
mov al, 0AAh
out dx, al
ret
Unlock_Chip Endp
;[]================================================
; Name : Write_Reg
; IN : CL - register index
; AL - Value to write
; OUT : None
;[]================================================
Write_Reg Proc Near
push ax
mov dx, 4Eh
mov al,cl
out dx,al
pop ax
inc dx
out dx,al
ret
Write_Reg Endp
;[]================================================