En la ayuda de CCS viene lo siguiente, espero sea lo que buscas.
make16( )
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Syntax:
i16 = MAKE16(varhigh, varlow)
Parameters:
varhigh and varlow are 8 bit integers.
Returns:
A 16 bit integer
Function:
Makes a 16 bit number out of two 8 bit numbers. If either parameter is 16 or 32 bits only the lsb is used. Same as: i16 = (int16)(varhigh&0xff)*0x100+(varlow&0xff) except it is done with two byte moves.
Availability:
All devices
Requires:
Nothing
Examples:
long x;
int hi,lo;
x = make16(hi,lo);
Saludos