Solved: brltty – USB COM Port Gets Immediately Disconnected - Lynxbee – Linux, Embedded, Android, WordPress, SEO, Digital Marketing

When we connected our USB to Serial converter to Ubuntu 22.04, it got detected as ttyUSB0 but got disconnected immediately. Despite we tried many times, even after replacing cable, rebooted few times, the problem persisted and we were not able to access the USB to Serial Converter to access device terminal.

The dmesg logs observed are as,

[ 2009.094892] usb 1-3: new full-speed USB device number 8 using xhci_hcd

[ 2009.258550] usb 1-3: FTDI USB Serial Device converter now attached to ttyUSB0

[ 2013.175191] usb 1-3: usbfs: interface 0 claimed by ftdi_sio while 'brltty' sets config #1
[ 2013.176678] ftdi_sio ttyUSB0: FTDI USB Serial Device converter now disconnected from ttyUSB0
[ 2013.176745] ftdi_sio 1-3:1.0: device disconnected

When looked further, the actual error caused seems to be because of below line,

[ 2013.175191] usb 1-3: usbfs: interface 0 claimed by ftdi_sio while 'brltty' sets config #1

So, we tried to find what this “brltty” is,

$ sudo apt-cache search brltty

brltty - Access software for a blind person using a braille display

So, it is a package related to braille display. We tried to remove this package,

$ sudo apt-get remove brltty

And now, we disconnected and reconnected USB to Serial Converter, and it found to be working properly and stable.

[ 2166.464720] ftdi_sio 1-3:1.0: FTDI USB Serial Device converter detected
[ 2166.464883] usb 1-3: Detected FT232RL
[ 2166.465794] usb 1-3: FTDI USB Serial Device converter now attached to ttyUSB0