Hello michu and antonio. Thanks for the feedback.
Unfortunately I have not managed to upload any sketches to the rainbowduino through the black widow device. I have powered it up using the JST but also through the 5v pin. What I found strange was that some onboard leds on the rainbowduino were still on when only tx,rx and gnd where connected between the two devices (no power was provided through jst).
@antonio - Thanks for the info, this makes sense. I found some posts in the past, where people said that using two atmega328 devices in such a configuration was not possible but this is the best explanation. As far as removing the atmega it is too risky so I prefer not to try it. I believe in some post that I came across in the past someone mentioned something about putting a resistor between some of the pins on the arduino but I cant remember what the purpose was exactly and where i found that post.
@michu - Since your configuration works, I can only think of two things that could be happening. 1) My black widow which is based on the duemilanove does something differently to your device. 2) Something I am doing is not right or I damaged the equipment.
I would like to believe that I am just doing something wrong. If we don’t manage to resolve this issue during the weekend I will have to place an order for a UARTSB device like antonio suggested. Please let me know if you have any other suggestions that can help me avoid that.
The link you have provided me in a previous post is great for checking the wiring. In other pictures i found, it was not clear where exactly the pins/wires were connecting and as you know both devices have more than one connections named the same and that brought some confusion as whether my wires were connected correctly.
My wiring is exactly the same as the diagrams with the exeption that I have provided a 9v input through the JST or a 5v input through the arduino.
Thanks,
M