JeeNode working!

After quite a while porting my arduino code to use the jeenodes instead of serial/xbee, and figuring out which pins on the "ports" map to digital pin numbers, I got it to work! I can control the pan/tilt mount remotely! (that's all I've tried so far) And it's quite acceptably fast - in fact pings hover aound 54ms!

The main challenge with porting the code was that instead of just throwing data at the serial port and letting the xbees deal with it, I have to think about how to break it into packets, and which packets I really need to send and which I don't. There is also the issue of sometimes having to wait to send data, which might become a problem later. For now I have two methods, one says "send it now if you can, else drop it" and the other says "try to send forever". If the channel was tied up, it would just freeze up there. Obviously there will need to be some middle ground, if I run into problems.

I also had to write code for the JeeLink (the usb dongle, which is basically just a SMD AVR and antenna), to make it appear to be a plain serial connection for the frontend software. It was easiest if the frontend changed as little as possible (not at all, actually). In future it will be extended to provide the sender node ID and so on. This may probably become a central server node that directs all the traffic to the clients.

I had to figure out the mapping of pins to the existing arduino pins I was using so I could plug the servos into the right ports. Also there are only 4 digital and 4 analog-in ports provided on the JeeNode, so I was worried that I was already using all the pins I had available. I looked at the JeeNode diagram and the arduino diagram and painstakingly mapped it out. Basically the RF12 module steals 5 of my digital pins, two of them PWM. But some pins are mapped to the I2C and SPI/ISP connectors also available on the JeeNode, and to the INT pin on each Port. So I should be able to recover 3 digital pins, 2 of which are PWM, and two more analog-in pins. So that provides enough room for some additional things I want to do :)