mult_r

Multiply two 16-bit fractional values, round into a 16-bit fractional result. Saturates only for the case of 0x8000 x 0x8000. When an accumulator is the destination, zeroes out the LSP portion.

Assumptions

OMR's SA bit was set to 1 at least three cycles before this code, that is, saturation on data ALU results enabled.

OMR's R bit was set to 1 at least three cycles before this code, that is, twos complement rounding, not convergent rounding.

Prototype


  Word16 mult_r(Word16 sinp1, Word16 sinp2)

Example

short s1 = 0x2000;/*   0.25 */

short s2 = 0x2000;/*   0.25 */

short result;



result = mult_r(s1,s2);

// Expected value of result: 0.0625 = 0x0800