A2090A ROM Patching

[TommyE]

Hello

Just got hold of an A2000 with A2620 and an A2090A, Kick2.05.

I want to patch and burn a new eprom in the A2090 to fix the 256MB limit, but I wonder if anyone has any experience with the A2090A patched.

Can I then create partitions larger than 256MB or will I just be able to use more than 256MB of the disk in many 256MB partitions?

Ideally I would like to have large partitions eg 4GB.

Also, If anyone has a A2090A patched ROM and wants to share, I will be most happy.


Regards
Tommy

[Jope]

RobTurbo may be able to help you.

http://eab.abime.net/showthread.php?t=82162

[TommyE]

Originally Posted by Jope

RobTurbo may be able to help you.

http://eab.abime.net/showthread.php?t=82162

Great post


Thank you for the pointer.

Regards
Tommy

[dalek]

I've been intending to do the same thing, just haven't got around to it.

In my searches I found:
http://www.traumstation.ch/hardware/...e/Amiga/A2090/

I _believe_ the kalal rom files are patched, but I haven't tested. You could test them if you are bored Or maybe I'm wrong :/

[TommyE]

Originally Posted by dalek

I've been intending to do the same thing, just haven't got around to it.

In my searches I found:
http://www.traumstation.ch/hardware/...e/Amiga/A2090/

I _believe_ the kalal rom files are patched, but I haven't tested. You could test them if you are bored Or maybe I'm wrong :/

Thanks for the link.

Compared the roms on my controller and the ones in the link. The ones in the link seems to be newer when looking with a hexeditor.

Burned them and tried but they didn´t work.

Machine booted, but no disks where identified at all.

Will see if I can patch the roms myself and try again.

Regards
Tommy

[e5frog]

Seems to me the patch is done on the U50 and U51 combined rom file (Unify Bytewise 8-bit in WinHex) at $01E0 where the unpatched version is:

82 FC 00 08 C2 FC 00 08

Which is changed to:

02 81 FF FF FF F8 4E 71

Then "Dissect Bytewise 8-bit" in WinHex to split the files again for burning in the eproms.
I have 27256 eproms as U50 and U51 in my machine, there's a lot of empty room. ;-)

I intend to do this myself later today.

EDIT:
The a2090-kalalrom*.bin files are indeed patched, they are ready to be burnt onto 2764 chips.
It's also a newer version than mine (5 May 1988), kalal is dated 8 Dec 1996...

[mark_k]

Originally Posted by e5frog

The a2090-kalalrom*.bin files are indeed patched, they are ready to be burnt onto 2764 chips.
It's also a newer version than mine (5 May 1988), kalal is dated 8 Dec 1996...

Someone just changed the date info, the actual driver version is most probably identical to yours.

[mark_k]

Originally Posted by TommyE

I want to patch and burn a new eprom in the A2090 to fix the 256MB limit, but I wonder if anyone has any experience with the A2090A patched.

Can I then create partitions larger than 256MB or will I just be able to use more than 256MB of the disk in many 256MB partitions?

Ideally I would like to have large partitions eg 4GB.

1GB is the largest disk size you can (easily/practically) use. Partition size shouldn't matter as long as they're all under the 1GB point. You probably need MaxTransfer = 0x1FE00 and Mask = 0xFFFFFE in your mount file. Edit: MaxTransfer is probably unnecessary.

Leave the first (auto-mounting/booting) partition as OFS since there's no way to specify MaxTransfer (or Mask) for an FFS boot partition.

hdddisk.device v34.4 does support what looks like HD_SCSICMD (SCSI direct). So it's possible that some SCSI-direct-using filesystem like PFS3 could potentially access past 1GB. But it's very unlikely, since hddisk's implementation of HD_SCSICMD is probably early/incomplete/inadequate.