Category : C Source Code
Archive   : QWKREP.ZIP
Filename : CVT.C

 
Output of file : CVT.C contained in archive : QWKREP.ZIP

/*** MSBIN conversion routines ***/

union Converter
{
unsigned char uc[10];
unsigned int ui[5];
unsigned long ul[2];
float f[2];
double d[1];
}

/* MSBINToIEEE - Converts an MSBIN floating point number */
/* to IEEE floating point format */
/* */
/* Input: f - floating point number in MSBIN format */
/* Output: Same number in IEEE format */

float MSBINToIEEE(float f)
{
union Converter t;
int sign, exp; /* sign and exponent */

t.f[0] = f;

/* extract the sign & move exponent bias from 0x81 to 0x7f */

sign = t.uc[2] / 0x80;
exp = (t.uc[3] - 0x81 + 0x7f) & 0xff;

/* reassemble them in IEEE 4 byte real number format */

t.ui[1] = (t.ui[1] & 0x7f) | (exp << 7) | (sign << 15);
return t.f[0];
} /* End of MSBINToIEEE */

/* IEEEToMSBIN - Converts an IEEE floating point number */
/* to MSBIN floating point format */
/* */
/* Input: f - floating point number in IEEE format */
/* Output: Same number in MSBIN format */

float IEEEToMSBIN(float f)
{
union Converter t;
int sign, exp; /* sign and exponent */

t.f[0] = f;

/* extract sign & change exponent bias from 0x7f to 0x81 */

sign = t.uc[3] / 0x80;
exp = ((t.ui[1] >> 7) - 0x7f + 0x81) & 0xff;

/* reassemble them in MSBIN format */

t.ui[1] = (t.ui[1] & 0x7f) | (sign << 7) | (exp << 8);
return t.f[0];
} /* End of IEEEToMSBIN */