I recently upgraded a headless station (a Toshiba Magnia SG20) that I have
from NetBSD 1.6 to 3.0. After the upgrade the headless station wouldn't
boot. I can only see some of the text (on a 16x2 LCD screen) but it looks
like the first chunk of the kernel loads and then the machine hangs.

Now I found a solution was to switched back to the biosboot_com0.sym
bootblock from NetBSD 1.6 (using the 1.6 installboot). I'm thinking the
problem is caused by the new boot block trying to talk to a VGA card. The
1.6 serial boot block doesn't output anything to VGA whereas the new boot
blocks output to VGA if it's available.

Anyway, I'm wondering if it would it make sense to add an option to the i386
boot block that would tell it not to try to talk to a VGA card. This issue
also might apply to other headless machines that do VGA emulation and output
the text to a serial port, like the boards from Soekris Engineering
(http://www.soekris.com). Does anyone know if they get double characters
output to the serial port?