In “Model-Based Design of Fixed-Point Filters for Embedded Systems,” Mark Corless and Arvind Ananthan of The MathWorks, Inc., describe the design of an acoustic tone controls application using Simulink and Matlab to develop an algorithm with selectable banks of fixed-point digital filters.

In this workflow, the algorithm specification begins in floating point. Simulation test benches are then created to explore and verify the behavior. The algorithm is then converted to fixed-point in stages. The test benches are reused to verify correct behavior is maintained throughout the elaboration of the algorithm specification to fixed point.

Automatic code generation is then applied to implement the algorithm in C code which takes advantage of processor specific intrinsic functions for fixed-point mathematics on an Analog Devices’ Blackfin processor.