comfun.c

sst89c54 isp program for user

//comfun.c
/*=================================================
send:=>stx,len,cmd,id[1],id[0],0x00,data,edc,etx
ack :=>stx,len,cmd,id[1],id[0],status,edc,etx
==================================================*/

#include "com.h"
#include "comfun.h"
#include "string.h"
#include "sst89cxx.h"
#include "public.h"


unsigned char ReadFile(unsigned char *buf,unsigned char length);
unsigned char CheckCrc();

unsigned char ReceiveData(void);
void  SendResponse(unsigned char status,unsigned char len,unsigned char *buf);
unsigned char IsShakeHands();


/************************************************************/
unsigned char ReadFile(unsigned char *buf,unsigned char length)
{
        unsigned char i,temp;
        for(i=0;i<length;i++)
        {
                if(ReadComm(&temp)!=TRUE)return FALSE;
                *(buf+i)=temp;
        }
        return TRUE;
}
unsigned char ReceiveData(void)
{

   unsigned char  length;

   timerout=10;

   //stx
   Buffer[1]=0x00;
   while(timerout--)
   {
        Status=ReadFile(Buffer+0,1);
        if(Status==0x00)
        {
                if(Buffer[0]==COMM_STX)break;
        }

   }
   if(Status)return COMM_STX_ERROR;

   //len
   Status=ReadFile(Buffer+1,1);
   if(Buffer[1]>(COMMMAXLEN-3)||Status)
   {
          return  COMM_LEN_ERROR;
   }
   length=Buffer[1];

   //data  and xorcode
   Status=ReadFile(Buffer+2,length+1);
   if(Status)return COMM_DATA_ERROR;

   //etx
   Status=ReadFile(Buffer+2+length+1+1,1);
   if(Buffer[2+length+1+1]!=COMM_ETX||Status)
   {
             return COMM_ETX_ERROR;
   }
   else
   {
             Status=CheckCrc();
             if(Status!=COMM_OK) return COMM_CRC_ERROR;
   }
   return TRUE;

}

///////////////////////////////////////////
//检验crc:
unsigned char CheckCrc()
{
	unsigned char i,CrcCode;

	CrcCode=0X00;      //PRESET_VALUE;
	for(i=0;i<Buffer[1]+3;i++)
	{
	       CrcCode^=Buffer[i];
	}
	if(CrcCode==0x00)return TRUE;
	else     return FALSE;

}
//////////////////////////////////////////
//发送数据
void  SendResponse(unsigned char status,unsigned char len,unsigned char *buf)
{
        unsigned char i;
        unsigned char xorcode=0;

        xorcode^=0x60^status^(len+1);

        WriteComm(COMM_STX);        //Delay(1);
        WriteComm(len+1);           // Delay(1);
        WriteComm(status);          //Delay(1);

        for(i=0;i<len;i++)
        {
                WriteComm(buf[i]);  //Delay(1);
                xorcode^=buf[i];
        }
        WriteComm(xorcode);         //Delay(1);
        WriteComm(COMM_ETX);
}

unsigned char IsShakeHands()
{
        unsigned char temp;
        while(1)
        {

                WriteComm(0x55);
                temp=0x00;
                Status=ReadComm(&temp);
                if(temp==0x55)
                {
                    WriteComm(0x0f);
                    return TRUE;
                }
                if(Status!=TRUE)return FALSE;
        }
        return FALSE;
}