Demo ready software with 4 digital drums and 2 analog drum triggers. UI protoboard is read and written to.
IIR filter algorithm added, IIR filter added to interrupt routine, filter sweep demo mode added, changed default pattern for drums
Added bit crusher
Added downsampler
Filter demo used during presentation, user button switches between LPF, HPF, Bitcrusher, Downsampler and no FX
refactoring
* Implemented filters with menu

* BUG: Noise when LPF and HPF are selected together