单片机系统指令的功能指令答:一、字节交换指令XCH A, Rn若(A)=80H,(R7)=08H,执行后(A)=08H,(R7)=80HXCH A, direct若(A)=80H,(40H)=F0H,执行后(A)=F0H ,(40H)= 80HXCH A, @Ri若(A)=80H , (R0)=6AH, (6AH)=0FH ,执行后(A)=0FH,(6AH)=80H二、半字节交换指令XCHD A, @Ri 累加器的低4位与内部...
51单片机C语言程序注释标注(写全)答:include <reg51.h> //调用头文件reg51.hvoid main() //主函数{unsigned char // 无符号字符型tab[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90,0x88,0x83,0xc6,0xa1,0x86,0x8e};//定义一个数组 LED数码管译码用的码表while(1) //主循环{P2=P2|0x07; // P2口...