[Gghc-discuss] I know you guys are getting sick of this, but...

[Jonathan Manton]

Ok, new ideas.

Instead of using 2 arduinos for prototyping, we get an ATMega644P in a 40-pin DIP package.  It has 32 I/O lines - we need 30, and 2 for I2C, so that is perfect!

Also, someone else has already ported the Arduino software to that chip (see http://sanguino.cc/).  Heck, we can even use their circuit layout as a starting point.  I have one of the FTDI cables that are needed to program it using the Arduino IDE.

The big benefit of this is we can prototype everything on breadboards.  And it will fit into the case, under the LCD, unlike 2 arduinos + tons of wires coming out of them.  And then the "final" version can just be a circuit board implementing the prototype, rather than having to go from 2 arduino Unos to a totally new circuit.

We use the 4066B, which also comes in a DIP package, for the analog switches.

For the audio sections (pre-amplifier for microphone, amplifier for speaker out) we use the LM386 audio amp, which I think I have a bunch of.

I would like to get the following button assortment from SparkFun (if you can find an alternate supplier with pretty buttons, we can order from them instead of SparkFun):  http://www.sparkfun.com/products/10302

I have plenty of LEDs for the prototyping, and the FabLab has small/cheap microphone and speakers.