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Re: Forcing a serial console for the kernel

On Sat, Mar 27, 2010 at 09:25:25PM -0700, STEPHEN JONES, W0TTY wrote:
> Is it possible to force a serial console for the install kernel  
> available in
> INSTALL.gz ?
> At the boot prompt defining consdev does not seem to have any affect.
> The particular machine is several thousand miles away, so I do not have 
> access to
> a floppy or cd drive.
> For a kernel that I've built, if I've set the option:
> options        CONSDEVNAME="\"com\"",CONADDR=0x2f8,CONSPEED=9600

Are you sure you want 2f8?  On typical PCs the serial ports start at 3f8
and 2f8 is the second one, isn't it?

If your system has serial BIOS, it is probably hiding the first serial
port from the bootblocks so they don't automatically detect it.  This
is a change you need to make to the bootblocks -- not the kernel.  Try
installboot (possibly with -e depending on your application) -o console=com0
-o ioaddr=0x3f8 -o speed=9600.  The "ioaddr=" option forces the bootblocks
to detect the serial port even though the BIOS claims it's not there.


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