sci.c

汽车电子解码器电缆测试。可以判断汽车故障在哪里

/******************************************************************************************
 *  目的：串口驱动
 *  功能：提供基本的串口操作接口
 *  模块依赖：MCS51 串口中断 硬件端口 及 操作方式
 ******************************************************************************************/
#include  "io8052A.h"
#include  "SCI.h"

#define lFosc 24000000   //晶振频率24MZ

struct _tagScon   //串口中断内部数据结构
{
     pFnSCON pfncon;     //串口中断指针
}    Sconer;


/*
**-------------------------------------------------------------------------------------
** 初始化串口中断处理模块 C51scon
**-------------------------------------------------------------------------------------
*/
void Init_SCI()
{
     Sconer.pfncon  = (pFnSCON)0;
}
/*
**-------------------------------------------------------------------------------------
** 读取读总线状态
**-------------------------------------------------------------------------------------
*/
char SCIRXD()
{
     if( P3_bit.RxD )
     {
          return 1;
     }
     else
     {
          return 0;
     }
}
/*
**-------------------------------------------------------------------------------------
** 送发送总线状态
** stat: 状态值 (TLOW~THIGH)
**-------------------------------------------------------------------------------------
*/
void SCITXD(unsigned char stat)
{
     if( stat )
     {
          P3_bit.TxD = 1;
     }
     else
     {
          P3_bit.TxD = 0;
     }
}
/*
**-------------------------------------------------------------------------------------
** 返回串口发送中断标志
**-------------------------------------------------------------------------------------
*/
char SCISE()
{
     if( SCON_bit.TI )
     {
          SCON_bit.TI = 0;  // 软件清0
          return 1;
     }
     return 0;
}
/*
**-------------------------------------------------------------------------------------
** 返回串口读中断标志
**-------------------------------------------------------------------------------------
*/
char SCIRE()
{
     if( SCON_bit.RI )
     {
          SCON_bit.RI = 0;  // 软件清0
          return 1;
     }
     return 0;
}
/*
**-------------------------------------------------------------------------------------
** 中断标志允许控制
** signal: 0表示不允许读取中断 1表示允许
**-------------------------------------------------------------------------------------
*/
void SCIENcontrol(unsigned char signal)
{
     if( signal )
     {
          SCON_bit.REN = 1;
     }
     else
     {
          SCON_bit.REN  = 0;
     }
}
/*
**-------------------------------------------------------------------------------------
** 查询方式向发送数据 byter
** 外部条件：当前串口中断不允许
**-------------------------------------------------------------------------------------
*/
void SCIsend(unsigned char byter)
{
     SCON_bit.REN  = 0;
     SBUF = byter;
     while ( !SCON_bit.TI )
     {
          //NULL
     }
     SCON_bit.TI = 0;
     ACC = SBUF;
}
/*
**-------------------------------------------------------------------------------------
** 查询方式读取当前已接收数据
** 外部条件：当前串口中断不允许
**-------------------------------------------------------------------------------------
*/
unsigned char SCIread()
{
     SCON_bit.REN  = 1;
     while ( !SCON_bit.RI )
     {    //WdtOn();
     }
     SCON_bit.RI = 0;
     return( SBUF );	
}
/*
**-------------------------------------------------------------------------------------
** 内部中断中发送函数byter
**-------------------------------------------------------------------------------------
*/
void SCIsendin(unsigned char byter)
{
     SCON_bit.REN  = 0;
     SBUF  = byter;
     //ACC = SBUF;
}
/*
**-------------------------------------------------------------------------------------
** 内部中断读取函数
**-------------------------------------------------------------------------------------
*/
unsigned char SCIreadin()
{
     unsigned char rbyte;
     rbyte = SBUF;
     return rbyte;
}
/*
**-------------------------------------------------------------------------------------
** 初始化串口,波特率flash,工作模式1,定时器2做波特率发生器
**-------------------------------------------------------------------------------------
*/
char SCIini(unsigned int flash)
{
     unsigned int buf;
     if(flash<=0||(lFosc/flash<32)||((lFosc/flash)/32>65536))    //  拨特率超出可设定范围
     {
          return 0;
     }
     IE_bit.ES = 0;      // 串口中断关闭
     IE_bit. EA  = 0;    // 所有中断关
     IP = 0x10;
     PCON  = 0x80;       // 串口波特率翻倍SMOD=1
     SCON  = 0x50;       // 串口工作模式1: 10位通用异步接收/发送器 REN=1
     T2CON = 0x30;       // 定时器2做波特率发生器
     buf = 65536-(lFosc/flash)/32;    // 计算波特率
     RACAP2L = buf;
     buf>>=8;
     RACAP2H = buf;      // 装入波特率
     T2CON_bit.TR2 = 1;  // T2置工作位,串口开始按指定波特率工作
     SCON_bit.RI = 0;    // 读中断标志0
     SCON_bit.TI = 0;    // 发送中断标志0
     IE_bit.EA = 1;      // 所有中断开
     SCON_bit.REN  = 0;
     return 1;
}
/*
**-------------------------------------------------------------------------------------
** 动态波特率设定函数
**-------------------------------------------------------------------------------------
*/
char SCIDynamicBuad()
{
     unsigned int baudrate;
     unsigned int time;
     time = 0;
     TMOD = ( TMOD & 0XF1 ) | 0x01;   //16位记数器
     TH0 = 0;                        //ms
     TL0 = 0;
     TCON_bit.TR0 = 1;   // T0置工作位
     TCON_bit.TF0 = 0;
     while( 1 )  //等待一个回应
     {
          if( !P3_bit.RxD )
          {
               break;	//遇到一个高电平
          }
          else if( TCON_bit.TF0 )
          {
               TH0 = 0;                        //ms
               TL0 = 0;
               TCON_bit.TF0 = 0;
               time++;
               if( time > 100 )  return 0;
          }
     }
     //0x55以当前汽车内定波特发给仪器
     TMOD = ( TMOD & 0XF1 ) | 0x01;   //16位记数器
     TH0 = 0;                        //ms
     TL0 = 0;
     TCON_bit.TF0  = 0;;  //初始化T0做记数器
     TCON_bit.TR0  = 0;   // T0置工作位
     while( !P3_bit.RxD );
     //TimeStart(TIMER0); //在开始收到0x55第一个位时开始记数
     TCON_bit.TR0 = 1;   // T0置工作位
     while( P3_bit.RxD ){ if( TCON_bit.TF0 )  return 0; }
     while( !P3_bit.RxD ){ if( TCON_bit.TF0 )  return 0; }
     while( P3_bit.RxD ){ if( TCON_bit.TF0 )  return 0; }
     while( !P3_bit.RxD ){ if( TCON_bit.TF0 )  return 0; }
     while( P3_bit.RxD ){ if( TCON_bit.TF0 )  return 0; }
     while( !P3_bit.RxD ){ if( TCON_bit.TF0 )  return 0; }
     while( P3_bit.RxD ){ if( TCON_bit.TF0 )  return 0; }
     while( !P3_bit.RxD ){ if( TCON_bit.TF0 )  return 0; }
     TCON_bit.TR0 = 0;
     //0x55收完,结束记数,计算和设定波特率
     time  = TH0;
     time <<= 8;
     time |= TL0;  //读取记数值
     baudrate = (unsigned int)(750000*64/(3*time)); //波特率=750000*64/(3*记数值)
     SCIini( baudrate );  //由定时器0记数 设定波特率
     return 1;
}
/*
**-------------------------------------------------------------------------------------
** 装入串口协议
**-------------------------------------------------------------------------------------
*/
char SCIload(pFnSCON pfnc)
{
     Sconer.pfncon = pfnc;
     SCON_bit.TI = 0;    // 清标志
     SCON_bit.RI = 0;
     IE_bit.ES = 1;      // 串口中断开
     return 1;
}
/*
**-------------------------------------------------------------------------------------
** 销毁串口协议
**-------------------------------------------------------------------------------------
*/
char SCIdestroy()
{
     if( Sconer.pfncon )
     {
          Sconer.pfncon  = (pFnSCON)0;
          IE_bit.ES  = 0;     // 串口中断关
          return 1;
     }
     return 0;
}
/*
**-------------------------------------------------------------------------------------
** 释放串口
**-------------------------------------------------------------------------------------
*/
void SCIRelease()
{
     IE_bit.ES = 0;      // 串口中断关闭
     PCON  = 0x80;       // 串口波特率翻倍SMOD=1
     SCON  = 0x50;       // 串口工作模式1: 10位通用异步接收/发送器 REN=1
     SCON_bit.RI = 0;    // 读中断标志0
     SCON_bit.TI = 0;    // 发送中断标志0
     SCON_bit.REN  = 0;  // 不允许发送
     Sconer.pfncon  = (pFnSCON)0;     // 回调指针 0
}
/*
**-------------------------------------------------------------------------------------
** 串口中断
**-------------------------------------------------------------------------------------
*/
#pragma vector=TI_int
__interrupt void SCON_INT(void)
{
     IE_bit.EA = 0; // 关闭所有中断
     if( Sconer.pfncon )
     {
          Sconer.pfncon();
     }
     IE_bit.EA = 1; // 开启所有中断
}
//----------------------------------------------------------------- End Of File --------