I have had two major problems so far with the exercises in the book. First, some of the samples (that continuously send output to the serial port) were causing my Arduino Uno to “hang”. I could not upload sketches, or reset. I had to try dozens of times to get it to reset the running sketch. The fix was to flash the 8u2 (USB chip) firmware with a new one that is included in Arduino 0022. Second, Processing was not recognizing the Uno’s port (it always showed /dev/ttyS0 instead of /dev/ttyACM0). The fix for that was to overwrite the RXTXcomm.jar and librxtxSerial.so files in Processing’s library with the ones from Arduino 0022. Finally, I still have to run Processing as root; even after adding my user to the uucp, dialout, and lock groups only root can create the dev locks. Update: Setting group write permissions on /var/lock and chgrp lock /var/lock fixed the dev locks problem.
Thank you very much for posting this information to the forum!
I suppose you’re running Linux?
Yes, in fact I run several varieties of Linux. In particular in this case it was Fedora 14 (but I also use Ubuntu 10.10). Flashing the 8u2 makes the IDE much more responsive!
On Fedora you’d do much better to install the distribution’s particular packages:
su -c “yum install arduino arduino-core arduino-doc”
the arduino package is modified to use /dev/ttyACM# on Fedora as the serial port