Monday, September 27, 2010

PS/2 Keyboard and Sanguino

So, I got a couple new toys and have resumed work on the "pile of junk," as I like to call it.  I ordered a Sanguino, two JeeNodes, a RBBB and a USB BUB kit.  I was disappointed to find that communication with the USB BUB didn't work, so I'll have to check that out more tonight.  The Sanguino is up and is in good shape though.  I struggled with getting a PS/2 Keyboard to work with the Sanguino, but the PS2KeyboardExt2 library worked perfectly with a Bare Bones Board, so I'll just have to learn more about the difference between the pins and hopefully make it work for me. 

I got the JeeNodes to try to do some wireless communication between an actor and a light board.  I'll solder the kits together soon, and learn to use them.  The bigger issue for me is learning about lighting board protocols, which may be regular MIDI, but I don't know yet.  That'll be next weekend's project for sure.  If anybody has some ideas/experience with that, let me know! Thanks!

That's about it.  Being in school while trying to do projects like this is tricky, but I think it should work ok.  Today is a writing/research day.  See you!

Thursday, September 23, 2010

Clave Metronome

I did this a little while ago, so sorry for not posting earlier. My chronology is all messed up. ; )

So, I play piano in a salsa band at MSU, and it is my favorite thing to do. In learning about how to play the music and what this whole other world of rhythm was all about, I learned about Clave: the rhythm, the instrument and the word. I got one, I learned that it is tricky for me, and that I needed more of it in my life, in addition to needing a steady clave rhythm to practice with.
So I made myself a new metronome.



This was a fun project for me. It has one of Paul Badgers' Bare Bones Boards inside, as well as a Minty Amp kit, some buttons for changing the tempo, adding mambo bell and cascara and changing back and forth between son and rhumba clave. I have had some practice with using switches, potentiometers and lights with and Arduino, but making them make sound and steady rhythms, and then amplifying it so that it's loud enough to practice with a piano required some learnin'.

To get the Arduino to make sound, I used one of the pins that was capable of Pulse Width Modulation (PWM) and used it as an Analog Output pin. The three sounds (one sound for clave, one for cascara and one for mambo bell) are each really fast pulse (or square) waves that are only played for a couple cycles (high frequency for a very short amount of time). The three different sounds are different frequencies and different lengths. The sound of connecting the Arduino directly to the speaker worked ok, but wasn't very loud, so I tried to amplify!

I still need to read more about Audio Amplifier chips, but this Minty Amps kit worked real well for amplifying my signal a little. Although, with regular audio, I'm pretty sure there's an impedance problem somewhere or something, because it was very distorted. I wanted to put in some potentiometers for different volume stages (one control for dropping the signal between the Arduino and the Amp, and one between the Amp and the speaker). However, I either wired the pots incorrectly or they're broken, so they just fizzle out in the middle. I put in two bybass switches, one for removing each of the pots from the signal chain.

Anyhow, I made it and I use it for practicing now, which is great, because this is one of my only projects that I actually use regularly. Total cost ~ $35
:-)

Sunday, September 19, 2010

evo-electro Conglomeration

This is a new project for me, and I'm very excited about it. It'll be a pile of broken electronics that were compacted together and left to rot for decades, except instead of rotting, it all grew together and came back to life in a conglomeration of intermittent functionality and mis-mapping.


This is the thing so far. It is four Apple towers (G3 and G4) cut up and hinged together in a shifting but stable frame. With the changing position, the mapping of different input (answering machine buttons, computer and MIDI keyboards) will change to connect to different output (sounds in computer speakers, lights on different devices, flashing of computer monitors).

I have many goals with this project. One of the main ones is to spend as close as possible to no money and use entirely recycled material (except for the driving Arduino and rechargeable batteries).

What's next:
  • put the top tier on - likely to be the side panel to a G5 tower
  • hack all the electronics in the basement and take note of what input and output I have
  • start breaking and attaching things
  • probably have to collect more wire

Things to learn:
  • output from PS/2 keyboards
  • sending information over VGA to a monitor (that may be broken)
  • programming a Sanguino
  • how to make this look corroded without damaging my house or my relationship with my roommates

(click here to see a gallery of the project so far)