2 Arduino USB NG Boards?


i would like to know if someone uses two (or more) Arduino NG USB boards with the same computer.
i need more than 6 analog inputs for PureData or MaxMSP patches and i wondered if analog (or digital) inputs/outputs from different boards work.

thank you and greetings,


If you don’t need more than 6 at one time you could consider a chip like the 74HC4051 analog multiplexer. It would allow you to connect up to 8 analog sources to a single analog input of the arduino.

A copy of the datasheet for the chip is available at http://www.fairchildsemi.com/ds/MM/MM74HC4051.pdf

Since I don’t believe the AVR can sample multiple analog channels simultaneously this chip just adds a bit of overhead and could give you up to 48 (6 arduino * 8 ch/74HC4051) analog channels on a single arduino!

thank you wandrson!

I’m afraid but i need more than 6 analog inputs at a time.
However your idea should be really a good one if I could recognize through the digital pins (input) the input of the multiplexer where i receive the signal.

I would like to use the two boards to build an Audio trigger to Midi/Pd/Max Converter for an Electronic Drums. Each part of the drum kit need a different signal path. Because It’s probably really hard to hit more than 6 parts of the drumkit at a time your help should be useful.

thank you.


The ATmega168 has 6 or 8 analog channels but only one ADC. Each of the channels on chip is multiplexed already. The 168 (arduino) does not currently provide simultaneous analog to digital conversion. The external multiplexers add some overhead to the process.

According to the data sheet the 168 ADC has a maximum conversion clock speed of 200kHz and takes 13 cycles to make conversion. This means that a conversion takes about 65 uS (max of about 15,000 conversions per second). To sample all six channels will take approximately 6 * 65uS = 390 uS. Compared to the 65uS conversion time the overhead of the 74HC4051 multiplexers are negligable.

In terms of your original question, I have connected two arduinos to my computer for communications. It didn’t seem to have a problem. Each arduinos maps to a different logical serial port.

Just found this in the playground. Thought it might help you. It describeds hooking up 64 analog sensors to a single arduino board.


Did you have any luck with reading two arduinos plugged into the one computer? Or did you have to use a hub? I’m thinking of doing the same thing.