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I have this system where I have 8 USB RFID readers which I would like to distinguish from one another. Here's a snippet from lsusb

Bus 002 Device 011: ID 05fe:1010 Chic Technology Corp. Optical Wireless
Bus 002 Device 012: ID 05fe:1010 Chic Technology Corp. Optical Wireless

As you can see both the idVendor and the idProduct is the same for the two USB RFID readers.

Q1: Can anyone help me do a --attrubute-walk with the udev info so I can see if there's any parameter that is unique to the individual readers. (I'm using Ubuntu 14.04 LTS)

This is the sys path I think I'm supposed to look in, and what the folder contains:

nicolai@nicolai-K53SV:~$ ls /sys/bus/usb/devices/
1-0:1.0  1-1:1.0  1-1.2:1.0  1-1.4      2-0:1.0  2-1:1.0  4-0:1.0  usb2  usb4
1-1      1-1.2    1-1.2:1.1  1-1.4:1.0  2-1      3-0:1.0  usb1     usb3

So of course I tried the following:

udevadm info --attribute-walk --path=/sys/bus/usb/devices/usb1
udevadm info --attribute-walk --path=/sys/bus/usb/devices/usb2
udevadm info --attribute-walk --path=/sys/bus/usb/devices/usb3
udevadm info --attribute-walk --path=/sys/bus/usb/devices/usb4

But I can't seem to find the two devices listed at the top (with ID 05fe:1010).

Q2: If there is a parameter that is unique to the individual reader, how can I (hopefully in python) distinguish between them?

Here's some python code which I thought I could use (until I realised that the ID's where the same for every RFID reader)

import usb

dev = usb.core.find(idVendor=0x05fe,idProduct=0x1010)
if dev is None:
    raise ValueError('Device not found')
    print('Device found')


A1: Here's the output from the lsusb -v:

As it can be seen the iSerial is just zero and all the other attributes are the same for both devices.

So for Q2: I was wondering if I could use the setserial bash command to write a serial to the USB RFID reader. If so, is this serial stored even after the power is lost, or do you have to create a script that creates the serials every time you boot?

Any suggestion is helpful.

share|improve this question
Does lsusb -v show a serial number? Probably called iSerial. – muru Jul 19 '14 at 4:57
No unfortunately. Here's the output: – Nicolai Anton Lynnerup Jul 19 '14 at 6:25
This is basically a duplicate of How to distinguish between identical USB-to-serial adapters? - the answer is that you will need to use the USB device path to identify devices. – bain Jul 19 '14 at 12:45

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