Genesis / Megadrive core ported to MiST

https://github.com/mist-devel/mist-board/wiki

Moderators: Mug UK, Zorro 2, spiny, Greenious, Moderator Team

Post Reply
phoboz
Atari User
Atari User
Posts: 36
Joined: Sun Jan 15, 2017 10:52 pm

Re: Genesis / Megadrive core ported to MiST

Post by phoboz »

It's a bit tricky to get stable builds now as the fpga is over 95% full. However there was some work done on the sdcard reader that I haven't tried yet. My sdcard became corrupt after heavy usage, so I need to reformat it. Please let me know if anyone has tried the newSD branch from github. Otherwise I will give you an update once I have tried it!

User avatar
vebxenon
Atari Super Hero
Atari Super Hero
Posts: 986
Joined: Fri Apr 24, 2015 12:10 pm

Re: Genesis / Megadrive core ported to MiST

Post by vebxenon »

phoboz wrote:It's a bit tricky to get stable builds now as the fpga is over 95% full. However there was some work done on the sdcard reader that I haven't tried yet. My sdcard became corrupt after heavy usage, so I need to reformat it. Please let me know if anyone has tried the newSD branch from github. Otherwise I will give you an update once I have tried it!
Do you have any binary of the new branch?
Just a computer and videogame lover :)

- Atari Jr 2600 clone
- Atari 7800 Peritel
- Atari XEGS
- Atari Lynx II
- Atari Jaguar
- MiST Board

User avatar
Sheldon
Atari freak
Atari freak
Posts: 67
Joined: Mon Mar 30, 2015 10:41 pm

Re: Genesis / Megadrive core ported to MiST

Post by Sheldon »

Hello,

any news ?

Best Regards.
Computers : Mega STE+(4Mo +HXC SLim and UltraSatan), Atari 1040 STe+( 4Mo + HXC SLim and UltraSatan), Atari 1040 Stf+(HXC SLim , Mega ST1+(HXC SLim and UltraSatan), FPGA Mist+Mistery Core( and other ...)
http://www.amedia-computer.com

phoboz
Atari User
Atari User
Posts: 36
Joined: Sun Jan 15, 2017 10:52 pm

Re: Genesis / Megadrive core ported to MiST

Post by phoboz »

Hello,
There is no bitstream (.rbf) file available for download, I have built the project but not tried it on the MiST yet. I will put the file on the mist-binaries repository once I have make a quick smoke test.

phoboz
Atari User
Atari User
Posts: 36
Joined: Sun Jan 15, 2017 10:52 pm

Re: Genesis / Megadrive core ported to MiST

Post by phoboz »

FPGAGEN Beta (2017-05-18) released :megaphone:

Please find the file:

Code: Select all

fpgagen-beta_20170518.rbf
under:
https://github.com/mist-devel/mist-bina ... es/fpgagen

I have done a quick smoke test, and the games I that usually play are working with sound. The game loading seems to be a bit more stable since the NewSD fix (see above)

:cheers:

Code: Select all

This is a port of fpgagen - Genesis/Megadrive core to additional platform(s)
MiST, Turbo Chameleon 64, Altera/Terasic DE2 board

The core shall be considered a work in progress as there are multiple issues:
1. Sprite flickering on heavy scenes, or on large sprites
2. No LFO modulation of the FM sound
3. Rom file formats supported are .bin and .gen, no support for .smd files
4. The design does not fit on the Altera/Terasic DE1 board anymore

==== Installing the core ====
If you are not buidling the core, copy the following files to the root of your sdcard:
fpgagen.rbf
Config_VGA/FPGAGEN.CFG, or Config_TV/FPGAGEN.CFG (for 15 kHz video)

Then rename the file fpgagen.rbf to core.rbf

breiztiger
Captain Atari
Captain Atari
Posts: 266
Joined: Sun Sep 20, 2009 6:54 am
Location: FRANCE

Re: Genesis / Megadrive core ported to MiST

Post by breiztiger »

hi

yes loading game is much strong

thanks for your work

DanyPPC
Atari Super Hero
Atari Super Hero
Posts: 856
Joined: Tue Feb 21, 2017 7:02 am

Re: Genesis / Megadrive core ported to MiST

Post by DanyPPC »

Good Job !
You are on the right way ;)

User avatar
vebxenon
Atari Super Hero
Atari Super Hero
Posts: 986
Joined: Fri Apr 24, 2015 12:10 pm

Re: Genesis / Megadrive core ported to MiST

Post by vebxenon »

:) Great! I will update at the evening
Just a computer and videogame lover :)

- Atari Jr 2600 clone
- Atari 7800 Peritel
- Atari XEGS
- Atari Lynx II
- Atari Jaguar
- MiST Board

User avatar
vebxenon
Atari Super Hero
Atari Super Hero
Posts: 986
Joined: Fri Apr 24, 2015 12:10 pm

Re: Genesis / Megadrive core ported to MiST

Post by vebxenon »

I've tested the core. OSD is too buggy and gets corrupted soon. But great progress on games :D, although most racing games have corrupted graphics, like Super Monaco GP.

Keep the good work!

Regards,

Salva
Just a computer and videogame lover :)

- Atari Jr 2600 clone
- Atari 7800 Peritel
- Atari XEGS
- Atari Lynx II
- Atari Jaguar
- MiST Board

Sorgelig
Ultimate Atarian
Ultimate Atarian
Posts: 6348
Joined: Mon Dec 14, 2015 10:51 am
Location: Russia/Taiwan

Re: Genesis / Megadrive core ported to MiST

Post by Sorgelig »

phoboz,

I want to port your core to my MiSTer(MiST ported to a larger FPGA-HPS) system. What branch is better to use?

phoboz
Atari User
Atari User
Posts: 36
Joined: Sun Jan 15, 2017 10:52 pm

Re: Genesis / Megadrive core ported to MiST

Post by phoboz »

Hello Sorgelig,
You should probably use the master branch, as it will be most stable (no experimets before tested)
I have merged in the NewSD branch, which only affects the MiST target.

Sorgelig
Ultimate Atarian
Ultimate Atarian
Posts: 6348
Joined: Mon Dec 14, 2015 10:51 am
Location: Russia/Taiwan

Re: Genesis / Megadrive core ported to MiST

Post by Sorgelig »

Hmm.. it look like a lot of redundant things in the core.. ZPU with firmware, SPI for SD...
Not optimized for MiST where you can simply choose required ROM from OSD.

phoboz
Atari User
Atari User
Posts: 36
Joined: Sun Jan 15, 2017 10:52 pm

Re: Genesis / Megadrive core ported to MiST

Post by phoboz »

Yes the osd, rom loading etc. is not utilizing the MiST firmware in full. This port was based on the pc engine core for MiST, which uses a completely different method for loading roms (zpu + firmware on the fpga). This approach occupies a lot of the fpga, so the fpga usage can be decreased if using the MiST method for rom loading on the MiST target. However it was not so easy to find a suitable 16-bit romloader matching the handshake interface of the core. If you are able to use the MiST method for loading roms, osd etc. please share your core. Then it would be possible to resume development on the MiST platform, as it is stalled now due to the fpga beeing almost full.

bernouilli
Obsessive compulsive Atari behavior
Obsessive compulsive Atari behavior
Posts: 102
Joined: Fri Jan 06, 2017 5:02 pm
Location: Paris/France

Re: Genesis / Megadrive core ported to MiST

Post by bernouilli »

@sorgelig: What is this Mister? I couldn't find anything on it but your repository.

Sorgelig
Ultimate Atarian
Ultimate Atarian
Posts: 6348
Joined: Mon Dec 14, 2015 10:51 am
Location: Russia/Taiwan

Re: Genesis / Megadrive core ported to MiST

Post by Sorgelig »

Because MiSTer is my project and currently i'm the only who is working in it.
https://github.com/MiSTer-devel/Main_MiSTer/wiki

btw, i've managed to clean FPGAGen from redundant parts and now it works on MiSTer using very similar to MiST API. Just need some time to polish the port.

User avatar
DrOG
Atari Super Hero
Atari Super Hero
Posts: 727
Joined: Sun Jul 31, 2016 8:23 pm
Location: Gyula, Hungary

Re: Genesis / Megadrive core ported to MiST

Post by DrOG »

Nice work, looking forward to it!

NegSol
Captain Atari
Captain Atari
Posts: 331
Joined: Sat Dec 05, 2015 9:22 pm

Re: Genesis / Megadrive core ported to MiST

Post by NegSol »

@Sorgelig - Really great project - I think you nailed the specs. This could really make some mist fans even more happy! We only need to find a solution to get USB devices attached. But I guess this should not be an issue considering the GPIOs on the board. I am already considering getting a board.

NegSol
Captain Atari
Captain Atari
Posts: 331
Joined: Sat Dec 05, 2015 9:22 pm

Re: Genesis / Megadrive core ported to MiST

Post by NegSol »

Okay, I now see the DE10 Nano got an USB OTG port. So all is good :)

bernouilli
Obsessive compulsive Atari behavior
Obsessive compulsive Atari behavior
Posts: 102
Joined: Fri Jan 06, 2017 5:02 pm
Location: Paris/France

Re: Genesis / Megadrive core ported to MiST

Post by bernouilli »

It sounds great.
I have questions though :
- why not use SRAM instead of SDRAM? Is it because it's more expensive and not available in high capacity?
- the is no SD card port, where do you store the files?

Gehstock
Captain Atari
Captain Atari
Posts: 430
Joined: Wed Dec 21, 2016 7:18 pm
Location: EastGermany

Re: Genesis / Megadrive core ported to MiST

Post by Gehstock »


NML32
Atari Super Hero
Atari Super Hero
Posts: 690
Joined: Tue Mar 11, 2014 1:54 am
Location: USA/Florida

Re: Genesis / Megadrive core ported to MiST

Post by NML32 »

I think a new topic should be created for the MiSTer.

phoboz
Atari User
Atari User
Posts: 36
Joined: Sun Jan 15, 2017 10:52 pm

Re: Genesis / Megadrive core ported to MiST

Post by phoboz »

A topic related to both Genesis and MiSTer is that: If there are enough gpio pins? SRAM could be put on one of the daughter boards in addition to SDRAM. If fpgagen were to use SRAM for graphics memory, the bandwidth problem which causes sprite flickering would most likely be gone. Since most 16-bit consoles and arcade boards, such as Capcom CPS use SRAM (or at least pseudo SRAM in the CPS case) such cores would be easier to develop and they would reflect the original hardware more closely.

Sorgelig
Ultimate Atarian
Ultimate Atarian
Posts: 6348
Joined: Mon Dec 14, 2015 10:51 am
Location: Russia/Taiwan

Re: Genesis / Megadrive core ported to MiST

Post by Sorgelig »

here is the port of FPGAGen for MiSTer:
https://github.com/MiSTer-devel/FpgaGen_MiSTer
Grab it in current revision since currently it uses very similar to MiST API and SDRAM. I plan to modify the memory module on this core to try to fix graphics problems. MiSTer has enough Block RAM to put Genesis RAM and VRAM there. ROM memory probably can be placed into DDR3.
About MiSTer itself, i will create a separate topic for Q&A.

Sorgelig
Ultimate Atarian
Ultimate Atarian
Posts: 6348
Joined: Mon Dec 14, 2015 10:51 am
Location: Russia/Taiwan

Re: Genesis / Megadrive core ported to MiST

Post by Sorgelig »

After i've replaced VRAM with BRAM, large sprite problem has gone!

Sorgelig
Ultimate Atarian
Ultimate Atarian
Posts: 6348
Joined: Mon Dec 14, 2015 10:51 am
Location: Russia/Taiwan

Re: Genesis / Megadrive core ported to MiST

Post by Sorgelig »

Another odd problem with this core is 3420/8 = 427,5 pixels in line...
For analog video it's not a problem while scaler IP using digital signal has problem...

Post Reply

Return to “MiST”