Beaglebone black is not enumerating as ttyUSB0

[pointers...@gmail.com]

My setup :

Ubuntu 14.04 LTS dual boot with windows 7.

I connected usb power cable which is a 5 volt supply. I also connected a usb to uart serial cable, and was able to see this to be as ttyUSB0 in ubuntu few days back.

After I did not see this ttyUSB0 only ttyACM0 (which I think is from usb power cable).

I have one doubt what is overcurrent?

I checked what power usb to uart cable is getting and it was 5 volts. I checked the voltage on serial header of beaglebone and it was 3.3 volts. How ever I am not connecting red cable on beaglebone black.

I am unable to understand what exactly is the problem?

Please respond anything related to it.

[epcm...@gmail.com]

The circuitry for the USB to UART cable is in the USB plug of the cable, so it should enumerate as /dev/ttyUSBx without plugging it into the board. If it doesn't appear then there is most likely an issue with the cable or the PC. If you run 

dmesg | tail 

on a terminal in Ubuntu a few seconds after plugging in the cable, you should be able to see if any errors are detected. You could also see if it is detected in Windows.

Hope this helps.

[Mrigendra Chaubey]

yes the issue was with uart cable. I don't have any debugger to see what is the problem but replacing it worked.