Problem with usb serial port ordering.

[Ben Scott]

On Feb 3, 2008 4:48 PM, Steven W. Orr <steveo at syslang.net> wrote:
> Does anyone know if there's a way to cause a specific device to always
> come up on a specified ttyUSB?

  Assuming the devices are actually different USB devices (and not two
units of identical models), you should be able to use the device
naming facilities on your system to set-up useful aliases, like
/dev/fp and /dev/spm.  Basically, you create pattern matches on
manufacturer/model, and assign names to the match.  Depending on
kernel version, distribution, etc., you will want to look in
/etc/udev/, /etc/usb/, /etc/hotplug, and/or /etc/hotplug.d/.  The
files are usually well commented.

  If the devices are identical in model, you're likely SOL: The USB
standard doesn't require a unique ID (e.g., hardware address, serial
number), so there's no sure way to tell identical models apart.  You
might be able to finagle something with port numbers or the like.

-- Ben