Hi, 

I'm talking about debugging an existing board (too big to be recreated on a bread board in less that 1 week...) with an arduino on it.

I just thought to two possibilities but they should be verified

case A)
if the "big board onboard" arduino is socketed, remove the existing 328p and provide the connection from the UNO connected to the ide. To be more practical has anyone made a cable for that ? I mean a cable that is not a mess of jumpers but a couple of flat cables with headers from the UNO to the 28 PIN socket. In this case not all PIN are necessary, for instance we can assume that the UNO is already powered and the +5V form the 28PIN to the UNO is not necessary

case B)
is it possibile to use the "big board onboard" ISP6PIN with an external UNO to program and debug ?
I really think it's possible to use it to program but can find a tutorial on how to use it to debug, just in case is it possible.

Any other ideas ?

Best Regards

Hi,

I'll try to explaim myself better:

These are the so called "BIG BOARD"

http://www.e-licktronic.com/en/yocto-kit/43-yocto-v10-half-kit.html
with an Atmega1284P on board and ISP6PIN.

http://www.e-licktronic.com/en/nava-parts-kit/50-nava-tr909-clone.html
with an Atmega1284P 

The question is,
how can I program and debug the existing Atmega1284P ?

I'm pretty sure that using an UNO with the ArduinoISP sketch I can program the Atmega1284P but what about debugging ?

Is there a faster way to program the Atmega1284P using the ISP6PIN and Visual Micro ?

Last bit, of course the software running on those 1284p is using the Hardware serial for a midi port.

Since you answer it seems to be possibile, but I didn't find a tutorial for this. I mean i did't find a tutorial where the Debugged/programmed arduino is not the one connected via USB.

Thanks.