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SuperBoard II ROM/RAM Upgrade
Posted: Thu Nov 25, 2010 6:38 pm
by Frank
After 30 years i pulled out the 600 board and it works.
Only just 8KB RAM is not enough for loading OS-65D.
To free some sockets for RAM i combine the four Basic-ROMs to one 27C64-150.
Three free sockets are now available.
In one i took a 62256-80 RAM and bend the not fitting pins up.
Only a 74LS32 is needed to combine /Phi2 and A15. That is for /CS.
If there is an interest, i can documented more of the things to do.
There are no cuts neccessary for this conversion.
Greetings from germany,
Frank
Re: SuperBoard II ROM/RAM Upgrade
Posted: Fri Nov 26, 2010 7:06 am
by dave
Hi Frank,
Yes, it would be great for you to document your mods here.
Best regards,
Dave
Re: SuperBoard II ROM/RAM Upgrade
Posted: Fri Nov 26, 2010 7:57 pm
by Steve Gray
Nice work!
Yes, it would be nice to document your modifications.
Do you have a floppy drive on your system? What monitor rom are you using?
Steve
Re: SuperBoard II ROM/RAM Upgrade
Posted: Fri Nov 26, 2010 9:28 pm
by Frank
Hi Steve,
i will document it in the next week.
Yes, i have connected a floppy drive.
in 1982-1985 the "Elektor" Magazin published a OSI-compatible floppyinterface.
http://retro.hansotten.nl/uploads/eljun ... nior82.pdf
With an adaptercable you can connect it as it is to the expansionconnector of the 600-board (i do it w/o the 8t28 driver, only bridged).
You can use standard flopydrives with this floppyinterface, because the dataseparator is onboard.
My Monitor-Rom is a special version from a berlin specialist, who add some features. i missed my original 600 monitor-ROM.
With this configuration i was able to copy all my OSI-Disks (I found only 6 working copys out of this time).
All disks are now copied to a new blank disk without any errors (After so many years
).
Best regards
Frank
Re: SuperBoard II ROM/RAM Upgrade
Posted: Fri Nov 26, 2010 11:20 pm
by Steve Gray
Some nice info in that PDF! I wish I could read german
It would be nice to see some pics of your system. Would it be possible to dump your monitor rom for all to try? I can host it on my own C4P web page if you don't have a spot for it.
Yes, I'd like to back up my disks. Last time I tried most of mine were working, but that was a few years ago.
Steve
Re: SuperBoard II ROM/RAM Upgrade
Posted: Sat Nov 27, 2010 11:42 am
by Frank
Hi Steve,
it is written in dutch.
Dutch is partial similar to german, but in many cases strong to read for me.
The link below is written in english and descibes the VDU-card for the system with patches for OSI-DOS.
http://retro.hansotten.nl/uploads/eljun ... ducard.pdf
Yes, i readout the special monitor ROM.
Frank
Re: SuperBoard II ROM/RAM Upgrade
Posted: Sun Nov 28, 2010 4:47 pm
by Frank
I make a schematic for the RAM upgrade.
Also there is a combined BASIC-ROM file that fits in the 27C64.
If there are any questions, ask me.
Frank
Re: SuperBoard II ROM/RAM Upgrade
Posted: Fri Oct 28, 2011 11:21 am
by dave
Hi Frank,
Thank you for documenting that. I have added your mod to the tips/tricks section of the website, along with a transcript of this thread as a kind of read-me file. Does the consolidated BASIC image include the garbage collection fix? If not, I can provide a fixed ROM image.
Best regards,
Dave