I once made an ISA card holding a DAC, with parallel data transport to bus. Programmed using BorlandC. It uses was measuring the load/unload curves of all sorts of batteries and calculating some parameters.
For fun i made a radio, for frequency , all copper , except "inverse lanes", two layers, design with kicad software.
For fun i made a radio, for frequency , all copper , except "inverse lanes", two layers, design with kicad software.