Re: [uCsimm] Changing special environment variables?

From: M. B. Anand (
Date: Mon Feb 12 2001 - 18:07:00 EST

I have had the same problem. According to the ucsimm manual, "if the
bootloader requires operator input, the console is initialized regardless of
the value of the CONSOLE." Even if AUTOBOOT is set to a number of seconds,
the bootloader still requires input because it is waiting if there is a
character. Now, if AUTOBOOT is set to yes and AUTOKEY is also set to
iknowmyimageworks then it would boot without delay and, presumably think
that no operator input is required. Note that this a dangerous thing to do,
if your boot image fails there is no way reset anything, although I do
remember seeing a message on this list a while ago to handle this situation.
Note also that the OS has to be informed separately also not to use the
serial port for printk. I hacked a couple of places to do this, I dont
remember imm'ly but I can dig it up if you want. It was some file under
arch/... where serial console is registered with printk.


----- Original Message -----
From: Joel Smith <>
To: <>
Sent: Monday, February 12, 2001 2:18 PM
Subject: [uCsimm] Changing special environment variables?

> Hello,
> I'm new to the list. I'm doing a university senior project using the
uCsimm and
> need to use the serial port for another device which doesn't want to see
> from the console. We have the uCsimm autobooting, so we can get to it via
> network, and won't need the serial port as a console. But we can't
change the
> CONSOLE environment variable. We've tried from the bootloader prompt and
> bootloader API, and both give the same results. First we tried unsetting
> variable:
> setenv CONSOLE (or bsetenv("CONSOLE) from the API)
> which does nothing. A printenv still shows CONSOLE=/dev/ttyS0
> so we tried
> setenv CONSOLE=no
> which did not change the value of CONSOLE, but overwrote our AUTOBOOT
value with
> a "$"
> Any ideas? We have ordered Maxim's SPI->UART (MAX3111E) chip so we won't
> the builtin serial port, but now we can't reset the AUTOBOOT variable,
> makes the device a real pain in the neck to use.
> One more thing, does anyone know how to make the bootloader initialize the
> builtin serial port to speeds other than 9600 baud?
> Thanks in advance,
> Joel Smith
> This message resent by the list server

This message resent by the list server

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