Interested parties may be, er, interested to know that I've just done a basic port of CP/M to the 6502.

https://github.com/davidgiven/cpm65

It currently runs on the BBC Micro (and Master and Tube), and the Commodore 64 (very slowly). It adds relocatable binaries, necessary to make programs portable between systems, but is otherwise essentially CP/M 2.2, just rewritten for the 6502. Naturally, there is no software whatsoever for it...

Also, if you're interested in watching about 45 hours of Youtube, I recorded myself programming it. Videos will be appearing here:

https://www.youtube.com/playlist?list=PLuQ2s_IbSWv48cCusm2SIstRZL8K0zRDA

On Tue, 4 Oct 2022, David Given wrote:

> Interested parties may be, er, interested to know that I've just done a basic port of CP/M to the 6502.
>
> https://github.com/davidgiven/cpm65
>
> It currently runs on the BBC Micro (and Master and Tube), and the
> Commodore 64 (very slowly). It adds relocatable binaries, necessary to
> make programs portable between systems, but is otherwise essentially
> CP/M 2.2, just rewritten for the 6502. Naturally, there is no software
> whatsoever for it...
>
> Also, if you're interested in watching about 45 hours of Youtube, I
> recorded myself programming it. Videos will be appearing here:
>
> https://www.youtube.com/playlist?list=PLuQ2s_IbSWv48cCusm2SIstRZL8K0zRDA

I wonder how hard it would be to get it up on an Apple //e...

-uso.

On Tuesday, 4 October 2022 at 14:57:58 UTC+2, Steve Nickolas wrote:
> On Tue, 4 Oct 2022, David Given wrote:
> > Interested parties may be, er, interested to know that I've just done a basic port of CP/M to the 6502.
[...]
> I wonder how hard it would be to get it up on an Apple //e...

It should be easy --- the BIOS is tiny: https://github.com/davidgiven/cpm65/blob/master/src/bbcmicro.s

The trickiest bit is the read/write sector code. IIRC the Apple II does a lot of the disk controller stuff in software, to save money. So, a bare metal implementation would need to reproduce all this. The alternative is to run CP/M on top of the existing OS (which is what the BBC Micro port does --- the entire CP/M file system is in a big MOS file). But I know nothing about how the Apple II OS works, so someone else would have to do that.

(I did have a quick look at the Oric II documentation. It looks like it'd be a good match, with 64kB of RAM and a standard 1770ish disk controller, except the screen memory is at 0xB000 which breaks the RAM non-contiguous...)

On Tue, 4 Oct 2022, David Given wrote:

> The trickiest bit is the read/write sector code. IIRC the Apple II does
> a lot of the disk controller stuff in software, to save money. So, a
> bare metal implementation would need to reproduce all this. The
> alternative is to run CP/M on top of the existing OS (which is what the
> BBC Micro port does --- the entire CP/M file system is in a big MOS
> file). But I know nothing about how the Apple II OS works, so someone
> else would have to do that.

It's called RWTS, and the code is pretty well documented although I can't
understand it. The Apple /// has RWTS in ROM, which makes this stuff
easier, but nobody used the ///. 🤪

-uso.

On Thursday, 6 October 2022 at 14:30:03 UTC+2, Steve Nickolas wrote:
> It's called RWTS, and the code is pretty well documented although I can't
> understand it. The Apple /// has RWTS in ROM, which makes this stuff
> easier, but nobody used the ///. 🤪

Well volunteered, there!

Seriously, I've only ever even _seen_ an Apple II like, twice. (They're not common where I am.) But I'd love to get pull requests. Resources-wise, all CP/M-65 really needs is about 64-or-so contiguous zero page addresses and 6-7kB of free contiguous RAM, but of course the more the better. On a BBC Micro in high-resolution mode you get 2.5kB of free TPA, which isn't enough to do _anything_ in, but the good news is that as there's no software for CP/M-65 yet you don't lose anything...

(Also, if anyone knows of a reasonably open source 6502 assembler in 6502 machine code I want to port one.)

On 10/4/22 05:08, David Given wrote:
> Interested parties may be, er, interested to know that I've just done a basic port of CP/M to the 6502.
>
> https://github.com/davidgiven/cpm65
>
> It currently runs on the BBC Micro (and Master and Tube), and the Commodore 64 (very slowly). It adds relocatable binaries, necessary to make programs portable between systems, but is otherwise essentially CP/M 2.2, just rewritten for the 6502. Naturally, there is no software whatsoever for it...
>
> Also, if you're interested in watching about 45 hours of Youtube, I recorded myself programming it. Videos will be appearing here:
>
> https://www.youtube.com/playlist?list=PLuQ2s_IbSWv48cCusm2SIstRZL8K0zRDA

Were you aware of this project?

http://retro.hansotten.nl/6502-sbc/dos-65/

On Sunday, 9 October 2022 at 05:03:09 UTC+11, Steven Hirsch wrote:
> > https://www.youtube.com/playlist?list=PLuQ2s_IbSWv48cCusm2SIstRZL8K0zRDA
> Were you aware of this project?
>
> http://retro.hansotten.nl/6502-sbc/dos-65/

DOS/65 has a restrictive shareware licence.

On Sunday, 9 October 2022 at 03:32:49 UTC+2, emils...@gmail.com wrote:
[...]
> DOS/65 has a restrictive shareware licence.

Actually, from talking to floobydust on the 6502.org forums, who is the current maintainer, it may have been relicensed as GPL-v3. The documentation's a bit confused. If so, I've just wasted 45 hours of my life, but I wasn't using them anyway...