Intel M600 - Manual (Page 78)

PCM-9586 User’s Manual 68
MOV DX,2EH
MOV AL,F6H
OUT DX,AL
MOV DX,2FH
MOV AL,05H; Set 5 seconds
OUT DX,AL
;------------------------------------------
; Exit extended function mode |
;------------------------------------------
MOV DX,2EH
MOV AL,AAH
OUT DX,AL