参考程序

      5个74HC595一起，CLK和DATA脚分别连起来，
         LATCH脚独立控制
         

        SCLK     EQU     P0.1
        SDATA    EQU     P0.0

WRITE5950:      LCALL WRITE595
                SETB P2.0
                NOP
                CLR P2.0
                NOP
                SETB P2.0
                NOP
                CLR P2.0
                RET
WRITE5951:      LCALL WRITE595
                SETB P2.1
                NOP
                CLR P2.1
                NOP
                SETB P2.1
                NOP
                CLR P2.1
                RET
WRITE5952:      LCALL WRITE595
                SETB P2.2
                NOP
                CLR P2.2
                NOP
                SETB P2.2
                NOP
                CLR P2.2
                RET
WRITE5953:      LCALL WRITE595
                SETB P2.3
                NOP
                CLR P2.3
                NOP
                SETB P2.3
                NOP
                CLR P2.3
                RET
WRITE5954:      LCALL WRITE595
                SETB P2.4
                NOP
                CLR P2.4
                NOP
                SETB P2.4
                NOP
                CLR P2.4
                RET
WRITE595:       MOV R5,#08H
                MOV A,2AH
LOOP:           RLC A
                MOV P0.0,C
                SETB P0.1
                NOP
                CLR P0.1
                DJNZ R5,LOOP
                RET