#include<stdio.h>
#include<string.h>
#include   "..\lib\7188.h"


char cHI,cLO;
void compute_chksum(char cBuf[]);
int chk_chksum(char cBuf[]);
char HexToAscii(int iHex);

/* ----------------------------------------------------------------------- */
/* return : 0 --> OK
	    1 --> port value error
	    2 --> timeout
*/

int SendCmdToHitech(int iPort, char cCmd[], int iChksum)
{
int i,ret;
long t;

switch(iPort)
	{
	case 1 :
	case 3 :
	case 4 : break;
	default: return -1;  /* port must 1/3/4 */
	}

if (iChksum!=0) compute_chksum(cCmd); /* compute chksum */

i=0;
while (cCmd[i]!=NULL)
   {
   ToCom(iPort,cCmd[i]);
   i++;
   }

if (iChksum!=0)
   {
   ToCom(iPort,cHI);
   ToCom(iPort,cLO);
   }

ToCom(iPort,0x0d);	     /* send out 0x0D */
return(0);
}

/* ----------------------------------------------------------------------- */
/* return : 0 --> OK
	    1 --> port value error
	    2 --> timeout
	    3 --> chksum error
*/

int ReceiveResponseFromHitech(int iPort, char cCmd[], long lTimeout, int iChksum)
{
int i;
char c;
long t;

switch(iPort)
	{
	case 1 :
	case 3 :
	case 4 : break;
	default: return -1;		/* port must 1/3/4 */
	}

i=0; t=0;
for(;;)
{
while(IsCom(iPort)==0)			/* wait response */
	{
	t++; if (t>lTimeout) return -2; /* time_out */
	}

c=ReadCom(iPort);		/* receive next char */
if (c==0x0d) break;		/* receive 0x0d --> end of command */
else cCmd[i]=c; 		/* store the command */
i++;				/* next char */
if (i>79)
   {
   cCmd[i]=0;			/* string must terminate with 0 */
   break;
   }

t=0;				/* reset timer */
}
cCmd[i]=0;			/* string must terminate with 0 */

if (iChksum!=0) return chk_chksum(cCmd); else return 0;
}

/* ----------------------------------------------------------------------- */

void compute_chksum(char cBuf[])
{
unsigned int i,j,len,sum;

len=strlen(cBuf);
j=len;

sum=0;
for (i=0; i<len; i++) sum ^= (cBuf[i]&0xff);	  /* 0x0D not included */
sum=sum&0xff;
cHI=HexToAscii(sum/16); /* CHKSUM high byte */
cLO=HexToAscii(sum%16); /* CHKSUM low  byte */
}

/* ----------------------------------------------------------------------- */

char HexToAscii(int iHex)
{
if (iHex<10) return(iHex+'0');
else return('A'+iHex-10);
}

/* ----------------------------------------------------------------------- */
/* return : 3 --> chksum error
	    0 --> OK
*/

int chk_chksum(char cBuf[])
{
unsigned int i,len,sum;
char h,l;

len=strlen(cBuf); sum=0;
for (i=0; i<len-2; i++) sum ^= (cBuf[i])&0xff;
sum=sum&0xff;
h=HexToAscii(sum/16);
l=HexToAscii(sum%16);

if (cBuf[len-2]!=h) return 3;	/* compare CHECKSUM high byte */
if (cBuf[len-1]!=l) return 3;	/* compare CHECKSUM low  byte */
return 0;
}