So, it’s pretty obvious that OpenChord.org is at the end of it’s life.  It’s been that way for probably close to a year now, but I haven’t really had anything to update here.  However, in the meantime, I’ve been working on a different project – the making of a non-music-related game.  Instead, it’s a game designed to assist with memorizing flash-cards.  I still don’t have  a name for it, but you can try the beginnings of it here:

www.OpenChord.org/Zombies

That’s just kinda a basic example of fundamental gameplay.  It doesn’t include what I’ve been working on this last week, which is all back-end stuff to increase the functionality of the project.  Namely:

• Transitioning cards to an SQLite database, compatible with flashcards created in the popular Anki program
• Implementing a spaced repetition algorithm, so items you learn get reviewed at longer and longer intervals, and the items you failed at show up more frequently.

So, I’ve been busy with non-OpenChord stuff for the last month or two, but I finally cleaned a few things up and took a video of the MIDI update in action. Like the video mentions, if you’ve already got a V1, all you have to do is download the new firmware and flash it onto your kit – instructions on how to do that are in the last post. Basically, in addition to being a kick-ass Guitar Hero controller, the OpenChord V1 is now ALSO the world’s most inexpensive MIDI guitar. Of course, like I mentioned in the last post, there are a number of limitations – only certain chords are supported (although additional chords are easy to add in the firmware, depending on what you need), and the note velocity is constant. Also, you’re not really going to be able to play with a capo. Still, there are a lot of interesting things you can do with it, and really, it’s kinda fun to play a guitar that sounds like bells!

It’s just a start for now, but if you go check out the code page, you can find working code and the binary for adding MIDI over USB functionality to the V1 guitar.  All you need to do is download the binary file and then update the firmware with the .hex file, and it will then show up to your computer as V-USB-MIDI.

It’s somewhat limited in its current state, and based on how the V1 interprets data, it’s never going to be a particularly great MIDI guitar.  In its current state, it only can produce accurate data for individually fretted notes, so using capos and chords isn’t effective for generating music.  However, since the V1 circuitry doesn’t interfere with the circuitry of the underlying instrument, it’s  a great way to provide a secondary data stream from any stringed instrument.

Possible applications include:

• Controlling stage lighting
• Controlling effect pedals
• Experimental music production

Also, remember that this is first-generation code – if there are any bugs or if you notice something acting unexpectedly, please let me know at develop@openchord.org

Of course, with the MIDI firmware, the V1 won’t be able to play with any games – you’ll have to reflash the firmware to the standard V1 code if you want that.

We’re back, or at least back-ish – We’ll be at the Penny Arcade Expo in Seattle, going from September 3rd through the 5th.  Due to a number of factors, there’s a good chance that it’s going to be the last convention that we do, so we’re just going there and trying to have a good time.

Going along with the end of conventions, from here on out, we’re going to be donating 100% of our profits to charity – Child’s Play, to be exact.

One other quick thing to mention – we’ve added some new code to the binaries section on the Google Code page, new code that fixes a bug where the controller wasn’t being recognized by Windows Vista or Windows 7.

Just to let you know, we’re going to be at Maker Faire this coming weekend there in San Francisco!  Please come by and check us out if you’re in the area! We’ll be demoing the V1 as well as our work so far on the V1 Violin, and we’d love to see you!

We’re sorry, but in building a few more kits, we’ve noticed that there are occasional problems with a kit not working. At first, we figured that it was just some random errors in a handful of boards. However, with the help of the new oscilloscope, we’ve found the real culprit – on the D- line of the USB connection, there is a 10K pull-up resistor. It turns out that 10K is probably on the very limit of the effective range. Instead, it should be more along the lines of 1.5K Ohms, although anywhere between 1K and 5K should probably work.

The issue is that the 10K resistor is just doesn’t let quite enough current through to be able to pull the data line up to the “High” state and hold it there on it’s own. Depending on the hardware it’s connected to, the scope is showing that during long periods of being held “High”, with the 10K, the line drifts back to a semi-high state, where the host is presumably holding the line just too low below the 2.8V cutoff for the USB spec.’s High mark, or maybe just letting it float. At any rate, voltages that individual hosts see as “High” can vary surprisingly widely. For instance, some computers will see a 5v signal as “High” and some won’t – the spec. sets “High” at 2.8v-3.6v, but USB puts power out at 5 volts. Figure that one out. Unluckily, it turns out that the 10K resistors we’ve been using have been bringing the lines down to around 2.7-2.8v in a few cases, while being fine in others.

So we’re really sorry about all of this. If you’d like us to, we’re more than happy to send you some replacement resistors, or if you’d like, we’d be happy to pay the shipping and replace the resistors ourselves, test out your system, and update all the firmware for you. Just send us an e-mail, and we’ll work everything out.

If you’ve got some resistors lying around, here is the resistor in question that needs replacement:

Thanks again to everyone who came out to see us at PAX East!  It’s a little strange to not have to spend all day at PAX, but it’s also nice to get a chance to sleep!  We have gotten a lot of questions there about the setup we were using there at PAX, and we wanted to link you to them so you could go ahead and get set up playing Frets on Fire X, a fork from Frets on Fire that adds all sorts of sweet functionality, including themes.

So for the record, we were running our entire rig this weekend with the following badass combo:

Frets on Fire X

death_au’s 8-bit NES theme

It looks like this:

First off, thanks to everyone who’s been stopping by the booth, and especially those of you who bought a button to support Child’s Play!  It’s been exhausting, but it’s been great to meet all of you, and  your energy has really helped us keep motivated throughout the day.  I hope you’ve had fun, and it’s been great to hear some of your comments.  We’ve been talking about a bunch of different things to different people throughout the day, and we want to thank you all for the feedback you’ve been giving us – it’s been great to get your suggestions figure out ways we can try and make our guitars better.  You guys have really been giving our guitars a great test; there’s nothing quite like having a thousand or so people experiment with your prototypes to test durability (there’s even some scrapes in the original frets of the guitar from where the strings are scraping against it!). We’ve figured out that if you have 60,000 strangers living in your house, you should probably install the kit with the internal option, since it’s a bit more durable, but other than a small glitch or two every so often, we’ve even been really impressed with how our guitars are holding up. So thanks so much, and we hope you’re enjoying playing our guitars as much as we enjoy your energy!