I was just about to reply about it but someone beat me to it: https://github.com/eblot/pyftdi/issues/161#issuecomment-650555077 On 27/06/2020 14:29, Friedrich Romstedt via arch-general wrote:

Hi,

Since end of 2019 I am using the PyFtdi Python package by Emmanuel Blot to talk to an FTDI chip on some controller board. Documentation of PyFtdi is hosted on http://eblot.github.io/pyftdi/. FTDI (Future Technology Devices International) chips (and similar chips by other vendors) implement an Universal Asynchronous Receiver Transmitter (UART) via USB. This can then be used to send messages to the device and receive replies. According to http://eblot.github.io/pyftdi/installation.html, it is at least on Debian and Ubuntu Linux necessary to write an `udev` rules file in order to permit ordinary users access to such an USB device. I attempted to use PyFtdi on my Arch Linux box (patched daily) as an ordinary user, and successfully talked to the device without any additional `udev` rule. We (Emmanual and me) would like to find out why and how Arch is configured to permit this. As I observed this behaviour, I opened Issue #161 on https://github.com/eblot/pyftdi: https://github.com/eblot/pyftdi/issues/161. There were some posts by Emmanuel and by me, but we didn't achieve anything substantial so far. Furthermore, the question arises if there are more places other than PyFtdi where this result might be relevant. Finally it might apply also to other Linux distributions different from Arch Linux aside Debian and Ubuntu; the documentation of pyftdi maybe could be updated to reflect this.

Any pointer is welcome. Best wishes, Friedrich