IIdentifying USB device

Hi All,
  Can anyone help?

  I am running Ubuntu 10.10 on a Beagleboard XM. I have 2 USB device
connect both using the FTDI chip set. One shows up as ttyUSB0 & the
other ttyUSB1. But it depends which order they are plugged in. The
first always being ttyUSB0. I have 2 ‘C’ programs that access these
devices successfully based on the device names.

  If I have them both plugged in when I boot the system can I guarantee
which name will be associated with each device? How can I
programmatically decipher which device is which?


Each FTDI chip should have a unique "iSerial" value, so using udev you
should be able to define a specific name to each unit..

  idVendor 0x0403 Future Technology Devices International, Ltd
  idProduct 0x6001 FT232 USB-Serial (UART) IC
  bcdDevice 6.00
  iManufacturer 1 FTDI
  iProduct 2 US232R
  iSerial 3 FTE4RRAJ

Good overview here: