ComputerVoltageSources

I've got my basic code verified that implements an I2C to serial 
bridge.  I'm going to use this to replace my SpeakJet interface in my 
PSIM and move to an I2C implementation that uses the TTS256.

I've got the speech portion working to the TTS256. I've got to wait 
for Ken to document the TTS256 so I know how to implement pass through 
mode. This may be more of a challenge with all of the buffers and 
queuing.

Here's what I have implemented so far:
ATMEGA8 28 pin DIP, internal RC oscillator
mode selectable for two baud rates
  31250 with no flow control (e.g. a second MIDI output)
  9600 baud with SpeakJet flow control
832 byte buffer
default I2C address of 48 hex (address byte=$90)
mode selectable for alternate I2C address
  7 bit input to specify address

This is a one IC solution for interfacing to a SpeakJet through a 
TTS256. I'll probably implement another mode for direct interface to a 
SpeakJet without the TTS256 (it requires slightly different flow 
control)

With the addition of 2 resistors this can be used as a second MIDI 
output. I am using my PSIM to convert MIDI from my keyboard controller 
to I2C messages which I send to the ATMEGA8 for conversion to MIDI to 
drive my Ensoniq synthesizer.

I'm open to other feature suggestions for future expandability.

Dave