Hey, sorry for all the confusion. We’re still getting these things sorted out. The Wiki sounds like a great idea, it should be easy to set one up, as we’re already using one for the Arduino homepage.
What makes things complicated is that there are two independent baud rates:
(1) The download rate.
Used when uploading (aka downloading) a sketch to the board. This has to match the baud rate used by the bootloader that is burned onto the prebuilt boards before they are distributed. Older boards came with a bootloader set at 9600 baud, newer boards use 19200 baud; the IDE defaults to using 19200 baud.
In version 0002 of the software, this rate was settable via the “Serial port speed” menu in the Tools menu. In version 0003, you need to manually set the value of the serial.download_rate item in your preferences.txt file (to find the location of this file, open the preferences dialog in the Arduino IDE) while Arduino isn’t running.
In the future, this is something that should never need to be changed. All boards should come with a bootloader running at 19200 baud, and the software will default to 19200 baud.
(2) The debug rate.
This is the rate that your code uses to communicate with the computer. It is determined by the value passed to the beginSerial() command and the value selected from the Serial Monitor Baud Rate menu. It’s also the value you need to use in HyperTerminal, Processing, etc. to read data from your sketch. Version 0003 of the Arduino software with a USB Arduino board supports speeds up to 115200. Older versions of the software or serial boards only work at 19200 baud or slower. The maximum debug rate is independent of the version of the bootloader on the board.
Some suggestions for try to get Arduino working on your 10.4.4 machine:
(1) Make sure that the serial.download_rate in the preferences.txt file matches the one in the preferences.txt file on the 10.3 machine (and, therefore, the baud rate expected by the bootloader on your boards).
(2) The name of the serial port shouldn’t matter, as long as you’ve selected it in the Tools | Serial Port menu.
(3) Using the 10.3 machine, upload to the board a program that sends data over the serial port at 9600 baud (i.e. calls beginSerial(9600) in setup() and printString(“hello”); in loop()). Then plug the board into the 10.4 machine, select 9600 from the Serial Monitor Baud Rate menu, the correct serial device from the Serial Port menu, and turn on the serial monitor by clicking its toolbar button. Do you see the serial data (e.g. “hello”) in the editor console?
If setting the serial.download_rate preference doesn’t help, and you can’t see any serial data with the serial monitor, there may be some problem with the FTDI driver on your machine, and we’ll need to investigate. We have successfully used Arduino on 10.4.3, though.
Can you post the data that follows “Error inside Serial.()…” in the error you get when uploading your sketch on the 10.3.9 machine? That’s a new addition to the program (to flush any leftover data from the serial port before uploading) and the full message would be useful in getting it working properly.