FATAL: cannot open /dev/ttyACM0 : No such file or directory

Hardware Librem 5
1

I haven’t used my LibreM5 for a while.
When I charged the battery today and restarted the Librem5, an OS update came in. That went well.
Then I wanted to connect the LibreM5 to my Linux desktop via USB, but suddenly it didn’t work anymore.
I got this error message on the following command:
sudo picocom -b 115200 /dev/ttyACM0 ===>
FATAL: cannot open /dev/ttyACM0 : No such file or directory

What is the problem here and how do I solve it?

Please give advise, thank you.

BTW

The file is here:

ls -al /dev/ttyACM0

crw-rw---- 1 root dialout 166, 0 sep 16 18:05 /dev/ttyACM0

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2

Which raises the obvious question … is that command executed on the desktop or on the Librem 5?

I guess your starting point is: on the desktop, issue lsusb and see whether it shows a USB device corresponding to the Librem 5.

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3

Thanks for your reply.

The command is issued from the desktop/laptop. The result is:

xxxx@xxxx-Aspire-A515-57:~$ sudo picocom -b 115200 /dev/ttyACM0

[sudo] wachtwoord voor xxxx:

picocom v3.1

port is : /dev/ttyACM0

flowcontrol : none

baudrate is : 115200

parity is : none

databits are : 8

stopbits are : 1

escape is : C-a

local echo is : no

noinit is : no

noreset is : no

hangup is : no

nolock is : no

send_cmd is : sz -vv

receive_cmd is : rz -vv -E

imap is :

omap is :

emap is : crcrlf,delbs,

logfile is : none

initstring : none

exit_after is : not set

exit is : no

FATAL: cannot open /dev/ttyACM0 : No such file or directory

Meantime I have connected the LibreM5 to another laptop and there everything is fine and the connection is esablished normal.

I will later dive deeper in the problem.

1 Like
4

OK.

Some things to investigate when you come back to it:

  • the lsusb output, as suggested
  • confirm that /dev/ttyACM0 is being created as a result of connecting the Librem 5 (for example, I have /dev/ttyACM0 on my computer permanently and it is a completely different device and has nothing to do with the Librem 5) - or, related to that, see what else might be in /dev in order to confirm that you are using the correct device
  • try a different comms program e.g. minicom instead of picocom
  • check out whether you might have butchered a udev rule on your laptop
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