Embedded Systems Design, 2nd Edition

352 Embedded systems design

The only problem is that the next data pointer must be

checked to know when to reset it to the beginning of the buffer.

This provides some additional overhead. Many DSPs provide a

special modulo addressing mode that will automatically reset the

address for a particular buffer size. This buffer size is normally

restricted to a power of two.

Buffer underrun and overrun

The terms overrun and underrun have been described

throughout this chapter and have been portrayed as things to be

avoided when designing buffers and the system that supports

them. While this is generally true, it is not always the case and

there are times where ...