electronicpresskit

unfortunately I didn't have access to a midi interface to test this until recently, but I've got it uploaded and now experiencing another bug... if I set loop length >16 && <32, only steps 17-32 are played. So as an example, set loop length to 26 and hit play. Note that steps 17-32 are looped. Set the loop length to 32, and steps 1-32 are normally looped. this is with standard 1:0 progression. anyone else have this?

sweet! thanks!

I tested it a bit more and it seems any progression that is above 1:0 has this problem. I understand how this would be tricky to fix, and it is not going to keep me from using the machine, but it seems quite a big limitation to only be able to use the progression feature on 16 steps. All my patterns default to 32 steps so I expect all 32 steps to be played through when I adjust the progression. I love this feature, but I would probably not be able to use it live because I would have to think about which section I am on when I adjust the progression, and it is more difficult to predict the outcome, so more dangerous for performance. Too many variables to track.

I think I found a bug...with pattern length set to 32 if I change progression to fwd: 2 back: 3, only the steps 17-32 on will be played back. strangely enough if I set the progression to fwd: 2 back: 1 only steps 1-16 are played back and then of course if I set it to fwd: 1 back: 0 is plays normally. Does this happen for other people? Thanks! epk

cool schematic! although I haven't yet been able to understand exactly how it's accomplishing the limiting. I ended up using two inverting opamps to do the summing, then adding a 1N4148 reverse polarity after the first opamp to limit it's output to negative voltages, then added a 4.7v zener diode (reverse polarity) on the output of the 2nd stage to limit the range to 4.7v and this seems to be working.

I'm still pretty new to working directly with PIC's and microcontrollers in general, so this is good info to know! Now I get to learn how to limit an opamp's output voltage! Thanks! epk

So I'm planning to add CV control of the Swing amount on my MB-808 by simply adding a summing stage after the Swing pot. I'm wondering about how well the core will handle >+5v at the input though. Will it be ok if it gets hit with +10v or do I need to limit the output of my summing stage to 5v? Thanks! epk

First off, thanks to TK! Sequencing the MB-808 is great! I have two feature requests with the second being most fun: Feature #1: Tempo Fine Control hold down shift while adjusting the tempo encoder to get sub 1 bpm adjustments. I'm not sure what the right resolution would be, maybe .05 bpm per encoder click? Feature #2: Momentary Tempo Adjust hold down alt while adjusting the tempo encoder to make temporary tempo adjustments that snap back to the predefined tempo on release of alt. I think maybe .33 or .5 bpm per encoder click would be a good resolution? This provides a way to beat match similar to how DJ's push and pull the platter on a turntable. I added these features to the software sequencer I make and it's really a lot of fun! It makes it easy to forget about midi beat clock and just go drop in on a friends DJ set or whatever. I'd love to have this on my MB-808! :)