An experiment with FPGA for FM audio synthesis.
This arose out of an interest in electronic music synthesis algorithms and in particular the innovative way that Yamaha was able to achieve FM using logarithmic math. I was guided by the approach used in the PPPlay module player https://github.com/stohrendorf/ppplay but this design deviates significantly in that it doesn't attempt to do any of the percussion and it includes a more flexible routing approach that should allow extremely complex FM algorithms.
This was built and tested out on a custom board comprised of an STM32F303 MCU and a Lattice ice5lp4k FPGA driving an I2S DAC. More detail about the board is available here: http://ebrombaugh.studionebula.com/embedded/f303_ice5/index.html
This is working but incomplete - polyphonic audio can be played but setting up the FM algorithms still has to be done by hand and there's no realtime control on the patching.