Slide 21 of 67
Notes:
Let’s focus on the adder section for a moment.
Since this is a non-pipelined multiply and adder, the adder can stand alone. On the left side, the input to the adder is from the multiplier. We have not shown the labels above the MUX here, but the other two inputs are the A accumulator or either of the buses, the C or D buses.
We also have, at no additional overhead, the ability to do rounding and saturation as an output of the adder, as well as setting overflow flags and zero bits.
The multiplier adder is fairly sophisticated, and it creates a lot of flexibility for the programmer.