>>> Hi,
>>>
>>> I have two questions about BeagleBone Black.
>>>
>>> 1. Is there anyway to make it boot when plug into power adapter? By this
>>> I mean, without the matter of push the power button.
>>>
>>> 2. I see by console=ttyO0 cannot get the log printed onto serial now.
>>> Although I know console=tty0 can still make the logs printed to a
>>> screen, but showing on the serial is always easier for debug. So is
>>> there anywhere I can check the new console name?
>
> The console was moved to ttyS0, but should still show output on ttyO0. I
> still use ttyO0 and get a warning during the boot:
>
> [ 0.004075] WARNING: Your 'console=ttyO0' has been replaced by
'ttyS0'
>
> I do use an RS232 cape for my serial console[1], so perhaps it differs. Can
> anyone else confirm?
>
Hi Paul,
Thanks for your info.
Well, I tried "console=ttyO0" and it do not work yesterday. While just
now I switched to "console=ttyO0,115200n8" and it works all of a sudden,
not sure why. So at last my working kernel commandline looks like
ro root=UUID=0dc43cd3-b7f5-47dc-8b74-5261d2dd7ded console=ttyO0,115200n8
console=tty0
You need to specify speed for the serial port, you can now with F-28+
also use ttyS0, the ttyO0 is an alias for compatibility.
By the way, I am using a cheap PL2303 serial, lsusb shows the
following.
Bus 002 Device 007: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial
Port
By the way, I don't know what hack takes effect, but today my BBB can
boot without push the button XD
I suspect it was powering on but the serial console negotiation was
causing random data on the console during u-boot which interrupted the
boot process. I've never had to press the power button on any of my
beaglebones to make it start.