Can you have multiple arduinos connected to same computer? - YES, FIXED

I have a project I'm working on where I'd like to have two instances of the IDE running, including having the serial monitor windows open - each one talking to a different Arduino via a different USB cable, plugged into a different port on my laptop.

One Arduino is a swimming pool pump controller project that I'm trying to troubleshoot and make a better program for.

The second Arduino is running a Sparkfun data-logging shield that is monitoring some of the outputs of the controller, particularly the pump control lines.

I'd like to be able to both watch the data-logger display, and the debug output from the pool control.

If it matters, I'm running Kubuntu Linux, and the 1:1.05 IDE...

Is this possible?

Right now what I find is I can have two IDE windows open, but both show as Arduino Uno on /dev/ttyACM0 [u]OR[/u] /dev/ttyUSB0 on the status bar. If I open the tool bar in the menu, the serial port option gives me whichever port is NOT on the status bar, with an unchecked box.

I can only seem to get one serial monitor window to open. Regardless of which IDE window I'm in, opening the window gets me the device that is on the status bar. Also opening and closing the serial monitor appears to reboot that device.

Is there a way to look at and / or send data to both arduino's at the same time?



Technically yes, you can communicate with more than one serial device that are on different ports. But I am not sure if the Arduino IDE can do this, as I don't use it.

Why not try installing another communications program, such as the program 'Serial Port Terminal' and have that talking to one Arduino, while you use the Arduino IDE communicate with the other?

There are many other communication programs you can use as well.


If you want to run two separate IDEs you need to start two, not just open a new window in the first one you opened, and yes that does seem to work, on Linux.

I often have two (or more) Arduinos connected to my Windows PCs (XP and 7). You must open a new [u]instance[/u] of the IDE for each Arduino like ChilliTronix says. Not only the IDE resets the Arduino, but most other serial terminal programs reset the Arduino on port opening. A 10uf cap from reset (pin 1 on Uno) to ground is supposed to prevent the reset. Also, on Uno at least, there is a jumper on the board that you cut that will prevent the auto reset, but you must manually reset the board to upload.

Is this possible?

Using windows and the 1.0.5 IDE it is possible. Someone reported issues with opening two separate instances of the arduino IDE using later versions of the IDE.

I should have stated that I am using 1.04 and 1.05 versions. I didn't know of the issue with newer versions.

Many thanks - as suggested I started a second instance of the IDE, instead of just opening a second sketch window, and that works quite nicely....

I currently have the development window for each Arduino open and the serial monitor that goes with them, and all appears to be running fine.