APPLICATION-SPECIFIC FUNCTION: ADD-SUB (ADDITION AND/OR SUBTRACTION )

The ADD-SUB function manipulates integers. It uses INPUT 1, INPUT 2 and INPUT 3 to calculate INPUT 1 + INPUT 2 - INPUT 3 and places the result in the CALCULATION OUTPUT.

The digital ERROR/OVERFLOW output is set to 1 when the series of operations provides a result outside [-32768, +32767] or when the ERROR PROPAGATION input is at 1. In all other cases, the ERROR/OVERFLOW output is at 0.

The digital ERROR PROPAGATION input is used to propagate errors (or saturations) from calculation functions (ADD-SUB or MUL-DIV) carried out upstream. If ERROR PROPAGATION is at 1, no operations are carried out and the ERROR/OVERFLOW output is set to 1.

If the ERROR/OVERFLOW input is not connected, it is fixed at 0.

If INPUT 1 and/or INPUT 2 and/or INPUT 3 is (are) not connected, it (they) is (are) fixed at 0.

To carry out a simple addition, simply do not use the INPUT 3 input.

To carry out a simple subtraction, simply do not use INPUT 1 or INPUT 2.

Parameterisation box/Comments tab