51单片机简单电子时钟程序,通过按键设置时间,有图,有解析!答:busy=P0^7;sbit key_ch=P3^5;sbit key_add=P3^6;sbit key_minus=P3^7;uchar i,sec,min,h,date,month,flag;uint year;uchar *chgstr[7]={" ","sec","min","hour","date","min","year"};uchar j,k,m,n,o,p;uchar code table[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,...