3.1.3.3 Modulo and Bit-Reversed Addressing Modes

The PIC32A architecture provides support for two special Register Indirect Addressing modes that are commonly used to implement DSP algorithms. Modulo (or circular) Addressing provides an automated means to support circular data buffers in X and/or Y memory. Modulo buffers remove the need for software to perform address boundary checks, which can improve the performance of certain algorithms. Similarly, Bit-Reversed Addressing allows one to access the elements of a buffer in a nonlinear fashion. This addressing mode simplifies data re-ordering for radix-2 FFT algorithms and provides a significant reduction in FFT processing time.

Both of these addressing modes are powerful features of the PIC32A architectures, which can be exploited by any instruction that uses Indirect Addressing.