www.pudn.com > czxtsycx1.zip > A20.ASM

OPEN_A20    PROC     
            PUSH AX 
            IN   AL,92H 
            OR   AL,2 
            OUT  92H,AL 
            POP  AX 
            RET 
OPEN_A20    ENDP 
CLOSE_A20   PROC     
            PUSH AX 
            IN   AL,92H 
            AND  AL,0FDH 
            OUT  92H,AL 
            POP  AX 
            RET 
CLOSE_A20   ENDP