ESP32 Forum

I'm trying to increase the UART speed for the monitor logging and for the most part I've been successful at it. However, there is a small first stage of the initial bootloader that still spits out only garbled symbols. It switches to proper text output from the second stage forward, but I could not get that initial part to work correctly.

What steps are necessary, meaning, which settings, in what places do I have to adjust to correctly set my speed from 115200 to 230400 baud or faster?

There is only one thing you can do:
- ignore it
Its from 1st stage bootloader and cant be controlled any way. The speed is hardcoded.

Hard-coded in the ROM, or hard-coded in the library code? I have no problem with modifying a component to make this work if that's what it takes.

Depending on the chip you are using, there may be an eFuse to disable ROM bootloader output entirely.

As for the baud rate itself, it is indeed fixed in the ROM bootloader. Since that's mask ROM that is part of the chip, the baud rate can't be changed.

Thanks for the heads-up. Sounds a bit like a design flaw. Perhaps something to address in future chip revisions?

Could you please explain, what specifically is the problem you are facing with the garbage output from ROM (other than cosmetic issue) and why disabling ROM bootloader output is not an option for your use case?

You must have misunderstood. My apologies for not being clear. I did not say that disabling ROM bootloader output is not an option for me and neither is the garbage output a problem—other than that it looks like a mess.
What I was trying to say, though, is that I wonder if there isn't a more elegant and future-proof way for something like this by not hardcoding a transfer rate, but to pull it from a preference variable instead that could be flashed. Just as a well-meaning suggestion…