Subject: Re: serial console
To: Chris Ross <>
From: Jeff Rizzo <>
List: current-users
Date: 01/22/2005 08:24:30
Chris Ross wrote:

> On Jan 21, 2005, at 14:52, David Laight wrote:
>> On Fri, Jan 21, 2005 at 11:51:44AM -0700, Co Thai Ngo wrote:
>>> Hi,
>>>  I would like to install NetBSD 2.0 by using a serial console with 
>>> boot-com. But I don't
>>>  know if there is any way so that I could change the baud rate when 
>>> booting the
>>>  computer with boot-com without rebuilding the sources. I have to 
>>> use the dafault baud
>>>  rate 9600 while my computer can run with the baud rate 115200. Any 
>>> suggestion and
>>>  comment is appreciated.
>> For NetBSD 2.0, you should just use the normal bootxx_ffsv1 (or 
>> equivalent
>> for the root filesystem type).  You can set the baudrate using the
>> -o speed=<baud rate> option to installboot (use -o console=com0 to 
>> select
>> a serial console).
>   David, I think you're misunderstanding his question.  He wants to 
> perform
> the *install* using a serial console.  I do this all the time, but I 
> must admit,
> mostly on sparc's, where it's much easier.
>   Looking at the man page for boot(8), there is of course the consdev 
> command.
> But, as you note, it simply allows you to specify use of a serial 
> console, not
> its baud rate.  I myself don't see a way to specify it.  Someone more 
> familiar
> with the boot code will have to speak up.
>   If it isn't possible, it should be.  I presume it wouldn't be too 
> hard to add this
> to the bootloader...
>                                          - Chris

I think you're misunderstanding David's answer.  You can use installboot 
to set the speed of the serial console for the bootblocks on the bootfloppy.

Something like (not tested):

installboot -o console=com0,speed=115200 /dev/fd0a /usr/mdec/bootxx_ffsv1

(this really doesn't belong on current-users;  either netbsd-help or 
port-i386 would have been more appropriate)