topic Re: u_boot prompt? in i.MX Processors

u_boot prompt?

BarryWarsaw — Fri, 30 Sep 2011 18:10:25 GMT

I've been reading about changing u_boot parameters, but I actually have no idea how to get a u_boot prompt to do this. i.MX53 QSB. I created a new boot microSD using the instructions on freescale, and the machine boots just fine, but I never see any kind of prompt before getting the Ubuntu desktop. I see a penguin in the upper left corner, then nothing until boot is complete.

Did I mess up the microSD flashing? Is there some key sequence I need to hit during the boot process? How can I get a u_boot prompt in order to change some of the boot parameters?

Re: u_boot prompt?

rogerio_silva — Fri, 30 Sep 2011 18:53:42 GMT

Take a look on your serial config on your pc. It must be set at: 115200 8N1 and port on my ps is /dev/ttyS0

Re: u_boot prompt?

fabio_estevam — Sat, 01 Oct 2011 19:58:26 GMT

When you power up the board, U-boot should come out on the serial console. You will have a few seconds to interrupt the boot process and get access to the U-boot prompt.

In order to interrupt the boot process just hit any key in the terminal (minicom/hyperterminal) during the very first seconds.

Regards,

Fabio Estevam

Re: u_boot prompt?

KrishnaPavan — Thu, 03 Nov 2011 05:54:40 GMT

You mean to say that it can be done so with the help of a RS232 Serial port also?

Because, I have tried and nothing could be done when the board is connected to RS232, But If I use USB2Serial, then its working fine.

Fabio Estevam said:

When you power up the board, U-boot should come out on the serial console. You will have a few seconds to interrupt the boot process and get access to the U-boot prompt.

In order to interrupt the boot process just hit any key in the terminal (minicom/hyperterminal) during the very first seconds.

Regards,

Fabio Estevam