/*****************************************************************
Name: AddCRCToCommand
Input Values:
char
*pszCommandString - the message to have a CRC added
remeber, we substitute the space with a :
Output Values:
char *
Return Value:
int - 1 if succesful, 0 otherwise
Description:
This function adds a CRC to the end of a command
and replaces the space with a :. The CRC is calc'd
using the CRC functionality found in the API
*****************************************************************/
int CCommandHandling::nAddCRCToCommand( char * pszCommandString )
{
int
m,n;
unsigned int
uCrc;
bool
bFirstSpace = FALSE;
if(strlen(pszCommandString) >= (MAX_COMMAND_MSG-6))
return 0;
n=strlen(pszCommandString);
/*
* determine 16 bit CRC
*/
uCrc = 0;
for(m=0;m<n;m++)
{
/*
* replace space character with : if sending CRC
* since parameter names can have spaces we need to
* replace only the first space with the :
*/
if(pszCommandString[m]==' ' && !bFirstSpace )
{
pszCommandString[m]=':';
bFirstSpace = TRUE;
}
uCrc = CalcCrc16(uCrc,pszCommandString[m]);
} /* for */
sprintf(&pszCommandString[n],"%04X",uCrc);
n+=4;
/*
*Add the carriage return to the end
*/
return 1;
} /* nAddCRCToCommand */
/*
* CalcBannerCRC
*/
unsigned short CalcBannerCRC(Banner &banner)
{
return CalcCrc16((unsigned char *)&banner + 32, 0x840 - 32);
}
