MiSTer FPGA Forum

Hi all,

this is my 2nd FPGA core for MISTer - another 8-bit Czechoslovakian computer Ondra SPO 186. It's almost fully implemented - only one missing thing is modern HW called Ondra SD for loading SW from SD cards.
Core as it is now is able to load SW from ADC line in and via serial port (user port) with appropriate 3.3V UART converted. If you use higher voltage you fry your mister!

Motivation for using the serial port was:
- it's exactly as it was used on real HW
- Ondra SD is not implemented yet
- I've ported this core to ZX Uno too and therefore I was unable to use all MISTer features like loading files with Linux core
- I was keen to try communication with other world from MISTer

Ondra doesn't bring any extraordinary graphics or unknown games but is interesting inside. Graphics screen generator is very smart. It's done with two 8253 timer generators. These are responsible for HSync and VSync signal as well as counting video ram addresses! Furthermore you can programmatically change screen resolutions. Smart, isn't it? And cheap - and this was at these days important too.


Here is link to github page with few more words about it https://github.com/MiSTer-devel/OndraSPO186_MiSTer
and here is small video showing Ondra core and PC application when loading games into it



And here is link to ZX Uno github https://github.com/PetrM1/OndraSPO186_ZXUno

Ondra SD implementation for easier SW load is in progress...

Enjoy it
Petr

That's brilliant. For me, at least, one of the most interesting aspects of the MiSTer is that way that keeps these rather obscure old computers alive.

It looks like someone really put a lot of work into porting all those Spectrum games, or was it made to be Spectrum compatible?

D.

Nice to read that

I'm not very familiar with Spectrum inside, but I'd say only compatible was Z80 CPU (here U880D - clone from East Germany). It had no ULA. Graphics was generated with 2x i8253 (USSR clone) programmable timers only (except some NANDs and one pulse generator) - so I'd say no, it was not compatible.

Unfortunately I can't say how easy or difficult it was to port spectrum games to it - it is out of my knowledge, I've never tried it

Is there a list of games for it?
Even a handful of selected titles unique to the platform is interesting to see.

I'm not sure how many games were made for this computer, probably not so many. There were only about 2000 computers made and most of them were not available for home users but schools. Only games available today are on following page https://sites.google.com/site/ondraspo1 ... ad/9-1-hry Please note zip files might contain more than one game. But in total it could be about 20 ....

But even so I'm glad this machine can line in FPGA now, I had a lot of fun creating it and learned a lot about internals. Much more then what I purchased it as a retro computer in real. I have some memories of this computer from my childhood when I was attending computer club...

Good effort, really great to have machines like this preserved and be able to check them out.

Will it be released to main soon?

it is already the case but not sure it was added on the wiki page.
Thanks @shark800 for this new core !

Many thanks, it is great to see small systems come the the MiSTer FPGA, this is a great help when it comes to preserving these systems for future generations.

Oh I forgot to put it on main wiki page, sorry, fixed now as well and notice in change log forum.

And think you for nice words

Petr

For some reason, the update script did not pick it up on my MiSTer, even though I can see the release file in the repository, and it is listed in the Wiki. Did it work for anyone?

I'm not sure about how update script works, but if it depends on wiki page I've put it there recently...

I had a look at //sites.google.com/site/ondraspo186 and noticed that the Ondra could run CP/M. Is this a planned upgrade for the FPGA core?

@shark800, many thanks for this new core!

Hi all,

here is new version of my Ondra SPO 186 core with big update - Ondra SD implemented in core. Ondra SD in new HW created by Martin - here is link to his web page about it https://sites.google.com/site/ondraspo186/4-rom-card-sd

This great HW enables fast SW load from SD card into real Ondra computer and I've adopted same approach (and used original SW on Ondra) to speed up and make easier SW load on the core.

Updated core as well as source codes are available on github https://github.com/MiSTer-devel/OndraSPO186_MiSTer together with small how to prepare SD card for it. Or you can get it with MiSTer update script

And here is my updated video captured on that new core


https://youtu.be/YnFbf-u1D80

Ondra SD doesn’t support calls for running CP/M yet – this will be available in next release

Enjoy
Petr

New version of Ondra SPO 186 core with Ondra Melodik is available now.

Ondra Melodik is new HW for old Ondra computer. It is a "sound card" with SN76489 chip. Here is link to HW author pages https://github.com/72ka/OndraMELODIK where you can find gerber files, visualization, demo application and many more.

And here is link to his demo application video with real Ondra


https://youtu.be/u5RyUs0VGdg

Updated core as well as source codes are available on GitHub https://github.com/MiSTer-devel/OndraSPO186_MiSTer
Or you can get it with MiSTer update script

Enjoy
Petr

Thank you for your continued work on this Core

shark800 wrote: ↑Thu Oct 27, 2022 7:14 am

New version of Ondra SPO 186 core with Ondra Melodik is available now.

Ondra Melodik is new HW for old Ondra computer. It is a "sound card" with SN76489 chip. Here is link to HW author pages https://github.com/72ka/OndraMELODIK where you can find gerber files, visualization, demo application and many more.

And here is link to his demo application video with real Ondra

https://youtu.be/u5RyUs0VGdg

Updated core as well as source codes are available on GitHub https://github.com/MiSTer-devel/OndraSPO186_MiSTer
Or you can get it with MiSTer update script

Enjoy
Petr

Thank you!

Have to test the games later, but there may be five more playable games/homebrew available here:
http://www.ondraspo186.8u.cz/?cat=5