51单片机键盘汇编程序答:KEYSCAN EQU 31H KEYTM EQU 32H KEYSEL:MOVKEYVAL,#0 MOVKEYSCAN,#0EFH LCALLGETKEY MOVA,KEYTM JZKEYS1 MOVKEYVAL,A SJMPKEYRTN KEYS1:MOVKEYSCAN,#0DFH LCALLGETKEY MOVA,KEYTM JZKEYS2 CLRC ADDA,#4 MOVKEYVAL,A SJMPKEYRTN KEYS2:MOVKEYSCAN,#0BFH LCALLGETKEY MOVA,KEYTM JZKEYS...
本人初学单片机,现请求各位大侠,有没有MCS51机的外部中断法4X4键盘扫描...答:ORG 30H MAIN: LCALL LOOP1 LCALL DELAY LCALL LOOP1 LCALL LOOP2 LCALL LOOP3 LJMP MAIN LOOP1: MOV P2,#0F0H;判断有键按下?MOV A,P2 MOV B,A MOV P2,#0FH MOV A,P2 ORL A,B MOV 30H,A CJNE A,#0FFH,LOOP11 LJMP MAIN LOOP11: RET LOOP2:MOV R3,#...