3.3 Reality Signal Processor (RSP)

The RSP is the processor used by the graphics and audio microcode. The RSP consists of a Scalar Unit (SU), a Vector Unit (VU), instruction memory (IMEM), and data memory (DMEM). The microcode is fetched from IMEM and has direct access to DMEM. The RSP can also access main memory using DMA. All memory references in the RSP are physical. However, the microcode uses a segment address table to translate segmented addresses provided in the task lists into physical addresses. The IMEM and DMEM are both 4 KB. The SU implements a subset of the R4000 instruction set. The VU has eight 16-bit elements.

For information on how the RSP is used to implement part of the graphics pipeline, please see Chapter 11, "RSP Graphics Programming". To learn how the RSP is used in audio processing, please see Chapter 17, "Audio Library".