C i b o M a h t o . c o m

Collin sent me a pre-release sample of his MidiVox kit to try out, so I dutifully soldered it up, and then proceeded to have some fun with . It’s a cool little add-on shield for the Arduino, consisting of a MIDI input jack, DAC and audio output jack, allowing the Arduino to act as a MIDI synthesizer. The board and components are beautiful, with cool curvy traces (which I suggest you consider from an aesthetic standpoint, not an engineering one) and solid connectors, and I had little trouble assembling it. The kit included 5-banded resistors, which I didn’t remember how to decode, (it turns out they are higher precision then their 4-banded cousins), but a multimeter did the job just fine.

Once it was all put together, I grabbed the pre-release version of the software, and after working through some issues to get it to compile on my Linux system (filename case sensitivity, we make everything difficult!), and uncovering (and fixing) a bug in the Arduino environment that prevented a supporting library from compiling, the sketch uploaded fine. I plugged in a MIDI patch cable and was busting out melodies from my MIDI keyboard in no time.

Then, OCD mode kicked in, and strange things were made to happen… Becasue my keyboard only has one adjustment knob, I wasn’t able to use it to tweak all of the synth parameters, so I wrote a PD sketch to expose all of the knobs:

(get the sketch)

Then, I decided that I really wanted to use a sequencer to feed the MidiVox, so I fired up Seq24 and made some patterns, throwing in a drum track generated by QSynth. This was all working great using the MIDI out through my keyboard, but I realized it would be much more convenient if I could control it directly through the USB connection. Well, Steven Hobley recently made a program to achieve this in Windows, but I couldn’t find anything like it for Linux. Instead, I hacked up a copy of ttymidi to work backwards. It’s a pretty incomplete implementation of a serial->MIDI bridge (ideally, it would support bidirectional messages of all kinds, not just note on/note off/control), but it seems to do the job. If you are interested, the hacked-up mess is here, and be sure to set your Arduino to 38400 baud.

At the end of it all, I was able to relax on my couch and control the MidiVox directly from my laptop, without a MIDI cable in sight… quite a bit of fun! If I get inspired sometime soon, I’ll try to clean up the hack job I did to ttymidi, and release it properly.

Extended the controller to handle all three drive axis, so now we can draw some things. Here is what came out:

Props to Matt S. for gently reminding me that this doesn’t require a super complex system, and that some tape and open loop controls are probably good enough .

Project code is now on github!

Matt, Andy and I built our Atari Punk Console kits tonight, so that we are ready for Synth Night 2 at Hack Pittsburgh. Hope to see you there! Video encoding deets after the break.
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Here’s a project I made back in 2006: a portable Intellivision. I took a cheapo LCD TV and combined it with a 25-in-1 Intellivision game toy, and managed to cram the whole thing into the shell of a broken gameboy. The whole thing worked out pretty well, except for the portability part. There wasn’t room in the case for a battery pack, so it had to be plugged in to work.

It ended up as a present for my friend Kevin, in remembrance of some fun we had in college when we wrote Fish Fish, a clone of the Intellivision game Shark! Shark!

Lathe experiment #2, machined out of a piece of solid aluminum rod. Basically, the ring is stuck because it was carved out of the rod. A collaboration with Matt Stultz.

I’ve decided to take a new direction with my art, so I created this wood gavel. Hope you enjoy it!

Actually, we just set up the donated lathe at Hack Pittsburgh, so this was a quickie project to try it out. It’s actually a metal lathe, so I’m anxious to get some metal stock and try it out!

Thanks to Matt Stultz for providing the sounding block and inspiration to take a nice photo of it!

Some time ago, I picked up an LCD photo frame that was on clearance, however it’s screen quality turned out to be quite unsuitable for actually showing photos. I wasn’t sure what to do with it, but I thought it would be a shame to waste the thing, so I decided to turn it into a ridiculous clock.

The idea is pretty straightforward, I just built a circuit to hit the ‘next’ button every minute, then generated 720 photos to store on it, one for each minute in a 12-hour cycle. I chose to write out the time in words, however really anything could be used and displayed. Build instructions after the break. Read more…