A 
Digital Signal Processor (
DSP) is a 
specialized microprocessor designed specifically for 
digital signal processing.  DSPs can also be used to perform general-purpose computation, but they are not optimised for this function.
Instead, they are usually optimised for:
-  multiply-add operations
-  deep pipelining
-  DMA processing
Most DSPs are fixed-point DSPs. However, floating point DSPs are common for more demanding applications.
Related terms:
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