#include <stdio.h>
#include <stdlib.h>
#include"..\lib\8000.h"

#define CrcError	   1
#define FunctionNotSupport 2

/* CRC16 Table High byte */
static unsigned char CRC16Hi[] = {
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x00, 0xC1, 0x81, 0x40, 0x01, 0xC0, 0x80, 0x41,
0x01, 0xC0, 0x80, 0x41, 0x00, 0xC1, 0x81, 0x40
} ;

/* CRC16 Table Low byte */
static char CRC16Lo[] = {
0x00, 0xC0, 0xC1, 0x01, 0xC3, 0x03, 0x02, 0xC2,
0xC6, 0x06, 0x07, 0xC7, 0x05, 0xC5, 0xC4, 0x04,
0xCC, 0x0C, 0x0D, 0xCD, 0x0F, 0xCF, 0xCE, 0x0E,
0x0A, 0xCA, 0xCB, 0x0B, 0xC9, 0x09, 0x08, 0xC8,
0xD8, 0x18, 0x19, 0xD9, 0x1B, 0xDB, 0xDA, 0x1A,
0x1E, 0xDE, 0xDF, 0x1F, 0xDD, 0x1D, 0x1C, 0xDC,
0x14, 0xD4, 0xD5, 0x15, 0xD7, 0x17, 0x16, 0xD6,
0xD2, 0x12, 0x13, 0xD3, 0x11, 0xD1, 0xD0, 0x10,
0xF0, 0x30, 0x31, 0xF1, 0x33, 0xF3, 0xF2, 0x32,
0x36, 0xF6, 0xF7, 0x37, 0xF5, 0x35, 0x34, 0xF4,
0x3C, 0xFC, 0xFD, 0x3D, 0xFF, 0x3F, 0x3E, 0xFE,
0xFA, 0x3A, 0x3B, 0xFB, 0x39, 0xF9, 0xF8, 0x38,
0x28, 0xE8, 0xE9, 0x29, 0xEB, 0x2B, 0x2A, 0xEA,
0xEE, 0x2E, 0x2F, 0xEF, 0x2D, 0xED, 0xEC, 0x2C,
0xE4, 0x24, 0x25, 0xE5, 0x27, 0xE7, 0xE6, 0x26,
0x22, 0xE2, 0xE3, 0x23, 0xE1, 0x21, 0x20, 0xE0,
0xA0, 0x60, 0x61, 0xA1, 0x63, 0xA3, 0xA2, 0x62,
0x66, 0xA6, 0xA7, 0x67, 0xA5, 0x65, 0x64, 0xA4,
0x6C, 0xAC, 0xAD, 0x6D, 0xAF, 0x6F, 0x6E, 0xAE,
0xAA, 0x6A, 0x6B, 0xAB, 0x69, 0xA9, 0xA8, 0x68,
0x78, 0xB8, 0xB9, 0x79, 0xBB, 0x7B, 0x7A, 0xBA,
0xBE, 0x7E, 0x7F, 0xBF, 0x7D, 0xBD, 0xBC, 0x7C,
0xB4, 0x74, 0x75, 0xB5, 0x77, 0xB7, 0xB6, 0x76,
0x72, 0xB2, 0xB3, 0x73, 0xB1, 0x71, 0x70, 0xB0,
0x50, 0x90, 0x91, 0x51, 0x93, 0x53, 0x52, 0x92,
0x96, 0x56, 0x57, 0x97, 0x55, 0x95, 0x94, 0x54,
0x9C, 0x5C, 0x5D, 0x9D, 0x5F, 0x9F, 0x9E, 0x5E,
0x5A, 0x9A, 0x9B, 0x5B, 0x99, 0x59, 0x58, 0x98,
0x88, 0x48, 0x49, 0x89, 0x4B, 0x8B, 0x8A, 0x4A,
0x4E, 0x8E, 0x8F, 0x4F, 0x8D, 0x4D, 0x4C, 0x8C,
0x44, 0x84, 0x85, 0x45, 0x87, 0x47, 0x46, 0x86,
0x82, 0x42, 0x43, 0x83, 0x41, 0x81, 0x80, 0x40
} ;

unsigned char CRCHi ; /* high byte of CRC initialized */
unsigned char CRCLo ; /* low byte of CRC initialized */

unsigned GetCRC16(unsigned char *puchMsg, int DataLen)
{
  unsigned Index ; /* will index into CRC16 lookup table */

  CRCHi = 0xFF ; /* high byte of CRC16 initialized */
  CRCLo = 0xFF ; /* low byte of CRC16 initialized */
  while (DataLen--){
    Index = CRCHi ^ *puchMsg++ ; /* calculate the CRC16 */
    CRCHi = CRCLo ^ CRC16Hi[Index] ;
    CRCLo = CRC16Lo[Index] ;
  }
  return ((unsigned)CRCHi << 8 | CRCLo) ;
}

unsigned long NowT,OldT;

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


int ReadModbusSlave(char cCmd[], int *Len, int *slv, int *fun, int *addr_h, int *addr_l)
{
int data,i,j,start,PP,ret,h,l;
char CC[80],flag;

OldT=(*TimeTicks);    // start timer

start=0; PP=0; flag=0; ret=0;
for(;;)
  {
  NowT=(*TimeTicks);
  if (start)
     {
     if (((NowT-OldT)>7) || (flag==PP))
	{
	h=GetCRC16(cCmd,PP-2);
	l=h&0xff; h=h>>8;
	h=h&0xff;
	if (h!=(cCmd[PP-2]&0xff)) return(CrcError);
	if (l!=(cCmd[PP-1]&0xff)) return(CrcError);

	(*Len)=PP;
	return ret;
	}
     }

  if (IsCom3())
     {
     data=ReadCom3();
     cCmd[PP++]=data;
     if (PP==1) (*slv)=data;
     else if (PP==2)
	     {
	     (*fun)=data;

	     if (data==1) flag=8;
	     else if (data==2) flag=8;
	     else if (data==3) flag=8;
	     else if (data==4) flag=8;
	     else if (data==5) flag=8;
	     else if (data==6) flag=8;
	     else if (data==15) flag=0;
	     else if (data==16) flag=0;
	     else		ret=FunctionNotSupport;

	     }
     else if (PP==3) (*addr_h)=data;
     else if (PP==4) (*addr_l)=data;

     if (start)
	{
	i=NowT-OldT;
	OldT=NowT;
	}
     else
	{
	start=1;
	i=0;
	OldT=NowT;
	}

     }
  }
}

show_hex_to_com1(int data)
{
int h,l,hh,ll;

l=data&0x0f; data=data>>4;
h=data&0x0f; data=data>>4;
ll=data&0x0f; data=data>>4;
hh=data&0x0f; data=data>>4;

if (l>9) l=l-10+'A'; else l=l+'0';
if (h>9) h=h-10+'A'; else h=h+'0';
if (ll>9) ll=ll-10+'A'; else ll=ll+'0';
if (hh>9) hh=hh-10+'A'; else hh=hh+'0';
ToCom1(hh);
ToCom1(ll);
ToCom1(h);
ToCom1(l);
}

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

int AnswerModbusSlave(char cCmd[], int Len)
{
int i,h,l;

h=GetCRC16(cCmd,Len);
l=h&0xff; h=h>>8;
h=h&0xff;
cCmd[Len]=h;
cCmd[Len+1]=l;
for (i=0; i<=Len+1; i++) ToCom3(cCmd[i]);
return 1;
}