Serial console access

Has anyone tried the bios serial console? I tried to use some adapters and access it, but I can’t have a console.
-checked if tx,rx are inthe wrong pins
-followed the tutorial using the minicom
-checked if the cables are well conected

Anyone got any ideia to try another way to access the bios serial console?

I would like to try as well, but don’t have the serial adapter board. Where did you buy it?

Btw, could it be that the debug UART port is 1.8V instead of 3.3V? Probably not, the debug UART on the UP2 is 3.3V.

Where did you get the debug port pinout?
There is pdf with schematic. Debug port at page 19.

The numbering on the serial adapter board is asymmetric. Try connecting on the other side of the board. I connected. Saw three error messages. I fixed the errors. But I never got to the bios. You might get lucky.)

P.S. I went into bios and turned on the console. It works

The debug UART is 1.8V.

from the schematics, I even switched the order to see if there it was any signal.

Is there other way to access the bios by serial interface? Don’t know if I’m understanding, but you never got to the bios, but after that it worked simple like that?

Did you had the hdmi connected during your tests?

oh well, so that explains a lot. Please put that info on the serial access console wiki of Rock pi X. I knew the pins were 1.8v, but the bottom interface for serial access I didn’t know.

To be noted…
I also got into BIOS via debug serial.
Same boad and cable, CH340 USB-Serial (5/3.3v capable, not 1.8)
Correct pin numbering is really on opposite side with “1.0mm” silkscreen
And yeah, serial redirection in BIOS turned off by default. May be depends on version.

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dude…thanks for your answer, I didn’t turned on this config in the bios, but I think this is the solution.

1-select the option for serial communication in the bios.
2-usb-uart 5v or 3,3v and watch for the inversion of pins while the flat cable is attached.

But… I can’t change this setting to test it because at the moment I don’t have a HDMI screen.