QUOTE
2.2.1.4 Intelligent Identifier Operation
The intelligent identifier operation outputs the
manufacturer code (89H) and device code (B4H for
28F010, BDH for 28F020). Programming equipment
automatically matches the device with its proper
erase and programming algorithms.
hence get 89 & BD for the flash line - note should go in lower case for eurasia/raincoat/linux i think
so that is how I got to the 89bd bit & 40000 coz it's 256kb
(80000 is for 512kb and 100000 - it's in hex and equals to a decimal value of 160000 but you enter it in hex)
it would probably screw the whole thing up but that is what I'd try if it was mine but like I say I could throw a mod on there if it went tits up
btw it's a 1.2 or a 1.3 xbox due to the conexant video chip so you could use an older bios but the usual Evox M7 or x2 4981 would have been my choice - though the D6 bios should be compatible on pre 1.4/Focus chip mobo's - but is just easier to use M7 or 4981 for any mobo except 1.6's of course
FINALLY AND MOST IMPORTANTLY
I AM NOT SAYING THIS WILL WORK OR OFFER ANY GUARANTEE's AT ALL - I COULD/WOULD TAKE A CHANCE COZ I KNOW I HAVE A MOD TO HAND TO GET ME OUT OF CRAP
Most likely it won't work coz I got something wrong yet again but I'd like to have given it a go coz it is something different
I am sure it does exist - heck I've done a "few" tsop's but never seen a SHARP tsop for myself - seen and done a few very early 1.0 US xbox's that had 3944 bios on them instead of the usual 4034 kernal but still never seen a SHARP TSOP for myself - just usual ST, Hyundai/Hynix & Winbond's
Recovered a few with own 32 wire homebrew but still never seen a Sharp for myself - yet I know they exist and sure your Intel TSOP is for real - had a genuine Intel celeron mobo with the bios on same type of Intel TSOP chip
perhaps take it back to shop or fit a mod on there but I think you are telling the truth and wish you the best
Heck if you was in UK I'd say bring it round let me have a go and I'd modchip it for free if I fucked it up - alas postage n all that ain't worth it
Best of luck though