3.15 DSP MAC Instructions

The DSP Multiply and Accumulate (MAC) operations are a special suite of instructions that provide the most efficient use of the dsPIC33A architectures. The DSP MAC instructions, shown in Table 3-11, utilize both the X and Y data paths of the CPU core.

MAC instructions are also capable of performing an operation with one accumulator, while storing out the rounded contents of the alternate accumulator. This feature is called Accumulator Write-Back (WB) and it provides flexibility for the software developer. For instance, the Accumulator WB may be used to run two algorithms concurrently or efficiently process complex numbers, among other things.