单片机控制RS485总线程序

RS485总线C程序，单片机控制，主机带分机。#include #define uchar unsigned char #define byte unsigned char #define BYTE unsigned char #define uint unsigned int #define word unsigned int #define word unsigned int #define WORD unsigned int #define Timeout 300 sbit Ctrl485=P1^0; uchar xdata combuff[]; void init_serialcomm(void) { TMOD=0x22; TL1=0xfd; TH1=0xfd; SCON=0x50; PCON=0x80; TR1=1; IE=0x90; EA=1; Ctrl485=1; } byte readRi(uint x) { while(RI==0) { if(x==0)return(0); x--; } RI=0; return(1); } void rec_serial_data(uchar rec_leng,uchar*sbufRam) { uchar i; sbufRam[0]=SBUF; RI=0; rec_leng=1; do { if(readRi(Timeout)==1) { sbufRam[i]=SBUF; rec_leng++; } else return; }while(RI==0);} void tarn_serial_data(uchar tran_leng,uchar*sbufRam) { uchar i; Ctrl485=0; for(i=0;i