osiweb.org

It would be nice if we had complete source for the OSI monitor rom (or maybe CEGMON or WEMON) so that it could be re-assembled with a modern assembler. We could then patch in support for additional features, such as a new disk system using FDC chip (1770, 1793 etc). It would be amazing if we had an...

Hi Steve, Welcome to the forum!! Thanks for creating your HexDOS way back in the day! HexDOS has been a highly sought piece of software by C1/SBII owners trying to reconstruct their disk systems. We would most certainly be interested in HexDOS code, comments, etc. It would be really interested to he...

Actually, garden variety drives will work with the existing interface, as long as a data separator is provided to demodulate the read data. There is no intelligence built into the drives. A 720k 3.5" drive, 1.4MB 3.5" drive, or 1.2 MB 5.25" drive should look just like an 8" floppy, if properly confi...

@Grant: Definitely would like to hear about the NOS keys. @Jeff: This document describes a keyswitch repair procedure in great detail: http://osiweb.org/repairs_and_mods/OSI%20Superboard%20II%20-%20Fixing%20Keyboard%20Switch.pdf It looks like it may be time consuming to go through the whole keyboard...

Thanks, Grant. I was looking for that article but could not find it.

That's actually a much easier mod than the first one, and the write-up is excellent. You don't get the guard bands, but 24 x 48 is actually pretty usable, and will also be similar to the later rev C1/SBII displays.

Dave

Nice work, Grant!

Dave

take look at peek(65) vol5 issues 2 and 3

http://www.osiweb.org/Peek65/Peek65_V5N2-02_1984.pdf
http://www.osiweb.org/Peek65/Peek65_V5N3-03_1984.pdf

I think a Speedup will depend on how the timing chains look after the mood, but should be easy. I will have a look when I'm back on town.

Dave

Hi Steve,

I can make images of them, and would be glad to do so. I'm out of the country at the moment. let's touch base when I'm back in a week.

Dave

Does the program appear to load and run properly? One thing you can do is start to boot, then reset and use the monitor to inspect the values at $00FD/$00FE (The load address), and $FF (The page count.) The ROM jumps to $2200 to run the loaded code, so you can also inspect the contents about that ad...

NULL only affects how many nulls are added for a new line on serial / cassette output. It seems that v3.3 added a command-line editor that provided that functionality a different way. I don't think it will make any difference if the NULL statements are removed.

Dave