课程设计多级通信系统

1、 多机通信系统单片机a,b,c. a为主机，bc为从机。a上有一个外部中断0输入，按第一次a的两个led亮500ms，再按一下，b机的两个led灯亮500ms，第三次按下c机的两个led灯亮500ms，然后周而复始。两个数码管分别显示0/1/2, 和abc（bc由从机反馈）/*主从通信基本步骤：1 主机从机初始化为方式2或者3，从机都置sm2=1，允许中断2 主机置tb8=1，发送从机地址3 所有从机均接收主机发送要寻址的从机地址4 被寻址的从机确认地址后，置本机sm2=0，向主机返回地址，供主机核对5 核对无误后，主机向被寻址的从机发送命令，通知从机接受或者发送数据。6 本次通信结束后，主从

2、机重置sm2=1，主机可再对其他从机寻址*/*主机a：*#include #define uchar unsigned char#define uint unsigned intuchar leddata=0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71,0x40,0x00;uchar mode;sbit p10 = p10;sbit p13 = p13;sbit p17 = p17;sbit p20 = p20;sbit p21 = p21;void uart_init() tmod

3、 = 0x20; th1 = 0xfd; tl1 = 0xfd; tr1 = 1; scon = 0xd0; es = 1; ex0 = 1; it0 = 1; /int0下跳触发 ea = 1; ti = 0;void delayms(int ms) uchar i; while(ms-) for(i=0; i120; i+);void putc_to_serialport(uchar c) sbuf = c; while(ti = 0); ti = 0;void mastercontrol(unsigned char addr, unsigned char comd) tb8 = 1; p

4、utc_to_serialport(addr); delayms(50); tb8 = 0; putc_to_serialport(comd); delayms(50);ex0_int(void) interrupt 0 p0 = leddatamode; p20 = 0; if(mode = 0) p2 = leddata10; p10 = 0; p13 = 0; delayms(500); p10 = 1; p13 = 1;/ mastercontrol(b,c);/ mastercontrol(c,c); else if(mode = 1) p10 = 1; p13 = 1; maste

5、rcontrol(b,o); / mastercontrol(c,c); else if(mode = 2) p10 = 1; p13 = 1; / mastercontrol(b,c); mastercontrol(c,o); mode = (mode + 1) % 3; com_int(void) interrupt 4 if(ri) ri = 0; if(sbuf = b) p2 = leddata11; if(sbuf = c) p2 = leddata12; void main(void) p0 = 0x00; p1 = 0xff; p2 = 0x00; uart_init(); m

6、ode = 0; while(1);*从机b：*#include #define uchar unsigned charuchar recdata;sbit p10 = p10;sbit p13 = p13;void uart_init() tmod = 0x21; th1 = 0xfd; tl1 = 0xfd; tr1 = 1; scon = 0xf0; es = 1; ps = 1; ea = 1;void delayms(int ms) uchar i; while(ms-) for(i=0; i120; i+);void putc_to_serialport(uchar c) sbuf

7、 = c; while(ti = 0); ti = 0;com_int(void) interrupt 4 if(ri) recdata = sbuf; ri = 0; if(rb8 = 1) /地址 if(recdata = b) /是自己的地址,置sm2=0,准备接受数据 sm2 = 0; putc_to_serialport(b); else /不是自己的地址 sm2 = 1; if(rb8 = 0) /数据 if(recdata=o) p10 = 0; p13 = 0; delayms(500); p10 = 1; p13 = 1; if(recdata=c) p10 = 1; p13

8、 = 1; sm2 = 1; void main(void) p0 = 0xff; p1 = 0xff; uart_init(); while(1);*从机c：*#include #define uchar unsigned charuchar recdata;sbit p10 = p10;sbit p13 = p13;void uart_init() tmod = 0x21; th1 = 0xfd; tl1 = 0xfd; tr1 = 1; scon = 0xf0; es = 1; ps = 1; ea = 1;void delayms(int ms) uchar i; while(ms-)

9、 for(i=0; i120; i+);void putc_to_serialport(uchar c) sbuf = c; while(ti = 0); ti = 0;com_int(void) interrupt 4 if(ri) recdata = sbuf; ri = 0; if(rb8 = 1) /地址 if(recdata = c) /是自己的地址,置sm2=0,准备接受数据 sm2 = 0; putc_to_serialport(c); else /不是自己的地址 sm2 = 1; if(rb8 = 0) /数据 if(recdata=o) p10 = 0; p13 = 0; delayms(500); p10 = 1; p13 = 1; sm2 = 1; if(recdata=c) p10 = 1; p13 = 1; sm2 = 1; void main(void) p0 = 0xff; p1 = 0xff; uart_init();