Consol do not work on Benna pi M2 Ultra

Hello Guys,

When I connect board by consol to computer it shows loading OS but I can not type any word or password by Keyboard. I have some benna pi M21 ultra but 3 from them have this problem. Could you guide me How solve my problem ? This is important for me

Try to catch all the messages with “minicom” or another terminal program and publish it on some or similar portal. We will take a look at it.

Ok, Thank you .we had about 15 benna pi that just 3 them have this problem.I got Debian on SD Card and it shows this Message.


If you are using minicom - try to check what are the options in menu:

press: “ctrl-a o” and go to “serial port setup”

there should be:

F- hardware Flow Control: No

G - software flow control: No

What do you mean by “cannot type any word or password by keyboard”? Do you mean that there is no echo of typed characters?

Second thing - there may some problem with the filesystem on your SD card, because kernel mounted it as a read-only.

Yes I can not type any thing and my keyboard do not work in this state . please explain more this message. “Second thing - there may some problem with the filesystem on your SD card, because kernel mounted it as a read-only.”

My OS works on other Benna pi

Do you use minicom? If yes - have you checked those options I mentioned?

The filesystem (ext4?) on SD card may be corrupted - and because of that the kernel remounted it as a read-only to don’t allow any modifications on this filesystem and corrupt it more.

I use putty, Is Minicom like Putty? I press: “ctrl-a o” but it do not work .

No minicom is quite different program. I don’t use putty but you can try to look for similar options like in minicom. I mean - turn off all the flow control in putty options.

Thank you. i searched it . it works like Putty . Minicom is a text-based serial port communications program. but I can not enter User name and password . could you suggest a solution that check UBOOT ?

I don’t think that the problem is in UBOOT.

So how can type , Could you suggest a other solution

Maybe the problem is in flow control as I said. Check the settings of the serial port in your windows (?) system.

Thanks I checked it . It is correct . Do you have other suggestion. This is important

Check the cables, switch the cables with the properly working boards, maybe the problem is in cable.

They are correct. I think it has a problem with hardware but i can not find it

Maybe RS232 (MAX3232) adapter is corrupted?

No, it works on other banana pi . on this board do not work. Is there a way that i test my hardware ?

I test it my hard ware part of uart is correct with out SD . The problem is with SD CARD . Do you know about this message " ext4_mb_generate_buddy:755: group 1, 1 clusters in bitmap, 0 in gd [ 68.820096] EXT4-fs (mmcblk0p2): Remounting filesystem read-only"

Thank you

I would try to use oscilloscope on RX pin on banana pi.

RX send data when I do not use sd card. Do you think my problem is with my OS ?