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Re: 3x problem with 0.9.7

Hello, (Petr Olivka) wrote in"> 
> mknbi-dos: why is required in root od ms-dos file system?
> where is command com I can say in config.sys.

That's just because I didn't think about putting anywhere
else but into the root directory. I will see if I can implement some-
thing into the next netboot release.

> mknbi-mgl: color R-G-B is in BIOS 4-2-1, not 1-2-4. The bug is still
> in source and documentation.
> And when I use const blue, black and red, and use them in print
> command, color of foreground not change. But when I use directly the
> ESC sequence, color change everytime.

I know about these bugs, but haven't had the time yet to find a fix.
Anyway, I'm planning on doing a whole bunch of changes to mknbi-mgl
but there again comes the time problem...

> And I have some problem with older ROM with new mknbi-linux. Image
> created with newer mknbi do not start correctly, because do not found
> correct ramdisk. New mknbi with new ROM work fine.
> Because I have ROM on HDD, is not problem quickly upgrade it. But
> maybe somebody in future will have the same problem.

This is due to a bug in older bootroms. There is nothing I can do
with it. The reason is the brain-dead construction of the typical
PC BIOS. In former times, when 64 MB of physical RAM was more than
anyone could finance, the BIOS didn't know about any memory which
was laying beyond the 64 MB boundary. Therefore, a BIOS system call
exists which reports the maximum amount of memory, but that call can
also only report up to 64 MB. The netboot bootrom used to use this
call in order to find the highest addressable memory location where
it could put the ramdisk. However, in the meantime 64 MB of RAM is
nothing special. You can buy computer with 256 MB or more at every
super market. Therefore, the BIOS creators invented various different
ways to let the BIOS report about the really installed physical memory.
Since mknbi-dos is now able to support larger ramdisks, the bootrom
had to know about the real amount of physical RAM, so I changed it
accordingly with version 0.9.7. Also, mknbi-linux and mknbi-dos had
to be changed to detect the real RAM size. But when those boot images
run on older bootroms, both the boot image and the boot rom think
about different RAM sizes, and therefore the boot image is unable
to find the ramdisk stored by the old bootrom.

There is only one thing I can do: the boot image should detect if
the bootrom is older than 0.9.7, and adjust it's RAM size accor-
dingly. Let me see if I can implement something for one of the
next versions...


Gero Kuhlmann, gkminix, Germany
Tollenbrink 18, 30659 Hannover   
Groote Gracht 33, 26723 Emden    
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