Re: USB-serial adapter suggestions needed

On Fri, 5 Jan 2024, Mark Millard wrote:

> I also request to again list the exact content of the two
> config.txt files --and again every time they are changed during
> this investigation.

I second this. There is way too much text in this conversation
and not enough data. It also does not help if every system is somewhat
different.

>> To all appearances, the troublemaker is powerd.
>
> I'd word it that powerd activity is involved --but is unlikely to
> be the only activity involved in the bad interaction(s). Lack of
> powerd activity (fixed rate context) likely avoids having the
> interactions at issue.

+1

I have skimmed the peripherial documentation for one of the Broadcom
chips (I think the one from Raspberry Pi 3) and it says that
the speed of the mini uart depends on the CPU clock frequency.

I could imagine a situation when mini uart speed changes during
downlocking the CPU.  There was suggestion to not use mini uart.
Use the port where the frequency is not changing with the weather.

I don't know how smart is the power management with powerd, but
I could also imagine shutting down peripherials or stopping the UART
clock as a potential power saving feature, so here you are.