Appendix A Watchdog Timer 77
;; Select The I/O Chip Program Configuration Register Logical Device
;; Input : bl = logical device number
SelectDevice proc
push ax
push dx
mov al,07h ;; Select Control Register 7 (CR07)
mov dx,cs:CONFIG_PORT ;;
out dx,al ;; Write to Config Port
jmp $+2
mov al,bl ;; Write Logical Device Number
mov dx,cs:DATA_PORT ;; to Data Port
out dx,al
pop dx
pop ax
ret
SelectDevice endp
