DoC again

[Roger]

On Wed, 2003-07-23 at 11:32, Martin Schmachtel wrote:
> These may sound like stupid questions to you, but please bear with me, I'm
> new to this stuff and have not found anything definitive on google about 
> it.

>From what I've seen, only the elite have dabbled into DOC's ;-)
You can find other info about MTD Developement and the DOC modules
within the MTD Mailling list.  Matter of fact, the developer for MTD has
the DOC's on his desktop.  DOC's should work and the only problems I
have seen tend to be chipset related.

> 
> M-Systems apparently no longer produces the Disk-on-chip millenium with the 
> part number MD-2800-D08. The successor MD-2802-D08 is supposed to be 
> compatible , but I'd like to be a little more certain about it. Has anybody 
> used the new chips with linuxbios successfully? 
> 
> Can any bios chip (in DIP-32 package) be replaced by a DoC? Or are there
> any requirements not all boards fullfil, like not all needed address lines
> are connected? More specifically, I'd like to try to get linuxbios working
> on my Asus P2B, which I hope will not be too difficult since some support
> for 440BX seems already present.

On my Tyan Tiger 1832DL (440BX) & Procomp B860/863 (440BX) motherboards,
I need to "unshadow" the bios chip to be able to have mtd (doc2001.o)
modules to see this chip.  

Basically, I aquired the openbios/devbios code and commented some lines
of code to prevent unshadowing after unloading the bios.o module -- if
you want this info, i can resend it.  It has already been posted once on
linuxbios & mtd maillinglists

I'm not sure if other 440bx boards have this problem (such as your
motherboard).  I've heard some 440bx motherboards not having this
"shadow" problem.

I have two of the MD2802-D08 chips and they work great on both
motherboards.  If you're iffy about the DOC's, you could always order a
couple of plan flash 32 pin dips.  I believe most of the later 440bx SMP
motherboards utilize a 256K flash.

If you want to use the extra Amtel flash dips for flashing them with
your manufacturer's compiled bios, you will need to use a chip size
equivalent to manufacturer's flash.bin file size (either 128K or 256K). 
(To check your flash size by doing a "ls -al" on your manufacturers
flash.bin file.  It will either be 128K or 256K.)

DOC Millennium 8MB Module
EMJ America Inc
http://www.emj.com/
Part No. 1MML8MB
(Tested on both of my 440BX motherboards.  Have not been able to boot
linuxbios -- due to doc ipl for 440bx in linuxbios?)

32 Pin w/ handle ARIES Zif socket (~$14 ea)
www.mouser.com
Stock No. 535-32-6554-11
Bin No. 94-68G1

DIP-32 256KX8 120NS Atmel Flash Memory (~$4 ea)
Stock No. 556-AT29C02012PC
Bin No. F0-59J8
(I have verified this chip on the Procomp B860/B863 motherboard but not
my Tyan.. it should work though)

Mouser, EMJ, Digikey all have online catalogs (in pdf format) and can be
easily searched via www.google.com.
-- 

Roger
http://www.eskimo.com/~roger/index.html