just a note a new revision to the mockup/spec has been added to my main post, and I am making good progress on the breadboard!
- gate/button ins are done. I was having a lot of problems that all stemed from me inadvertently using PNP transistors in place of what was supposed to be NPN
. Once I swapped those out everything worked perfect.
- Buttons have a very simple capacitor-based switch bounce filter. Thank you to @pichenettes for telling me about this phenomena on the MI forum. Most designs I found to combat this have a schmitt trigger IC going after this (some also had a diode in parallel to the grounding resistor…which I didn’t have space to do cleanly on the breadboard so I left it out). Not really sure if it’s really doing all that much in the current circuit, but it was very few components so I put it in there. I guess I’ll find out once I get the actual gerassic organ in there
- binary decoder chip is on there. all leds use the @corpusjonsey -style transistor led buffer so the logic signal coming out are nice, sharp square waves.
here is a few LFOs from stages playing the organ (by playing, I mean lighting up the green leds, audio at the end is just some drone playing in the background off my monitors)
