When developing code to enable two or more Arduinos to communicate and/or handshake with each other (e.g., over xBee or I2C), I am accustomed to running two or more instances of the IDE for each USB-connected Arduino 328 on my Windows XP system.
In this way, I can use the COM windows to watch the program execution and the dialog between the Arduinos. This greatly facilitates debugging.
It appears that v18 does not support multiple instances, however. Let's say that I have two Arduinos: #1 and #2. I plug Arduino #1 into an available USB port and invoke an instance of the IDE, selecting the COM port that Windows assigns to Arduino#1. Then, I plug Arduino #2 into another USB slot, and invoke a second copy of the IDE. I then select the COM port that Windows has assigned to Arduino #2. Doing so, however, switches the COM port assignment for the original instance of the IDE, making all copies of the IDE now connected to Arduino #2.
I hope this makes sense because I really need this multiple-instance control over multiple Arduinos. Thanks for anyone's idea what I might be doing wrong. Is there a better way to monitor multiple Arduinos while in debug/code editing mode?