vendredi 31 décembre 2010

EDIT 30/08/2011: This is not working .. cannot put negative voltage on the output 

Thinnking of  get ride of theses Transitors.
Will replace them with 2 TTL 74126 QUAD 3 STATE BUFFER
See the connections diagram below :

I didn't test it yet .. (don't have theses quad buffer at home)

It will be easier and much more "clean" because when Arduino pin is set on High there will be a High on the S&S bus, and when the Arduino pin will be Low, the outut on S&S bus will be High-Z. Has the S&S speech synth is PMOS, the PMOS pulldown resistors bring the line to logic 0.
With this method we don't need the -12V of the S&S.

1 commentaire:

  1. Hi Nick,
    Your project is very interesting !
    I own a french speak and spell "la dictée magique" and an arduino Mega since Christmas. Perhaps. I'm a beginner on arduino with midi, but I wish to learn... I follow you !