ex8-1.sdi

《单片机原理实用教程——基于Proteus虚拟仿真》一书的配套光盘

,,,        ORG 0000H
0000,02 00 30,START,START:  LJMP MAIN
,,,        ORG 0030H
0030,90 7F FF,MAIN,MAIN:   MOV DPTR,#7FFFH
0033,74 20,,        MOV A,#20H
0035,F0,LOOP,LOOP:   MOVX @DPTR,A
0036,30 90 05,,        JNB P1.0,INCD
0039,30 92 0B,,        JNB P1.2,DECD
003C,80 F7,,        SJMP LOOP
003E,24 20,INCD,INCD:   ADD A,#20H
0040,B4 E0 F2,,        CJNE A,#0E0H,LOOP
0043,74 20,,        MOV  A,#20H
0045,80 EE,,        SJMP LOOP
0047,C3,DECD,DECD:   CLR  C
0048,94 20,,        SUBB A,#20H
004A,B4 00 E8,,        CJNE A,#00H,LOOP
004D,74 20,,        MOV A,#20H
004F,80 E4,,        SJMP LOOP
000E,,,        END