A two step hardware design method using CλaSH

In order to effectively utilize the growing number of resources available on FPGAs, higher level abstraction mechanisms are needed to deal with increasing complexity resulting from large designs. Functional hardware description languages, like the CλaSH HDL, offer adequate abstraction mechanisms such as polymorphism and higher-order functions. This paper describes a two step design method to implement a DSP application on an FPGA, starting from a mathematical specification, followed by an implementation in CλaSH. A non trivial application, a particle filter, is used to evaluate both the method and CλaSH. First, a straightforward translation is performed from the mathematical definition of a particle filtering to Haskell, a functional programming language with syntax and semantics similar to CλaSH. Secondly, minor changes are applied to the Haskell implementation so that it is accepted by the CλaSH compiler. The resulting hardware produced by our method is evaluated and shows that this method eases reasoning about structure and parallelism in both the mathematical definition and the resulting hardware.