Access to ttyUSB* in Lazarus/Linux program

[bvn123]

/Why/ didn't it work? What does ls -l for the ttyUSBx device show? Did you remember to logout and then back in?
MarkMLl

Thank You MarkMLl,
it works too, and Your variant is simpler.
So, I added to dialout group user me:

Code: Pascal  [Select][+][-]

1. sudo usermod -a -G dialout me
2. <entered password>
3. <restarted Linux>

[MarkMLl]

Big grin here. I'm not sure whether having a user in BOTH dialout and plugdev is relevant, since the ttyXXX device will be in one group or the other as shown by  ls -a

You need to be aware of the udev stuff, but strictly it's something that you do when you buy a new board and is distinct from setting up user permissions.

Assuming that you're using some variant of Arduino, look carefully at the setup instructions that come with whatever type of board you go on to buy: this /particularly/ applies to Teensies where you have to get something JUST RIGHT (i.e. no trailing blank lines etc.) manually.

MarkMLl

[bvn123]

Assuming that you're using some variant of Arduino, ...
MarkMLl

Mainly I use CP2102 USB-UART bridges,
sometimes FTDI chips when USB to fast parallel port adapter is preferable.

[MarkMLl]

A useful thing about (genuine) FTFI chips is that you can "brand" them with a serial number, which makes detecting what's actually plugged in a bit easier. However enumerating device properties is an utter- and I hope that the community will turn an eye to my bad language /bitch/: while you can hook udev hotplug messages using (checks) NetLink, all too often you end up walking a file/directory tree in /sys

MarkMLl