Pure Data Software
This was a drum-machine / step-sequencer I made in Pure Data. It is basically a functioning instrument but I never finalized it with some of the features I intended to have like preset storage and step randomization. Feel free to mess around with it and repurpose any of the code. I don't think I'll be able to provide much support because I haven't looked at in a while.
Your best resource for an operational tutorial may be to view this video demo from when I was working on it.