51单片机按键控制数码管数据的加减答:DATEQU 30HSCANLEDEQU 32HFSDATEQU 33HORG 0000HLJMP MAINORG 000BHLJMP T0ISRORG 0030HMAIN:MOV SP,#5FHMOV TMOD,#01HMOV TH0,#0F4HMOV TL0,#048HMOV P2,#00HMOV SCANLED,#0MOV 30H,#2MOV 31H,#0MOV FSDAT,#20SETB EASETB ET0SETB TR0LOOP:JB P3.0,$JNB P3.0,$DEC FS...