Genesis / Megadrive core ported to MiST

[phoboz]

I would like to announce that the fpgagen Genesis / Megadrive core has been ported to MiST
Please watch the video: https://youtu.be/hT1NetIGBDg

[vebxenon]

Wow! That's real? I want it!

[vebxenon]

Although still no sound, it works like a charm as fas as I see

[phoboz]

Yes it's real, but still not perfect. So you should consider it a work in progress.
It does play Golden Axe with a 4 buttons gamepad. It plays an amazing amount of different games as well. 98% of all that I have tried so far.

The source are available at: https://github.com/phoboz/fpgagen
If you want I can build a beta core and publish it somewhere, maybe in the mist binaries repository.

As for the status:
The bandwidth of the SDRAM controller needs to be increased, because it has to handle RAM, ROM and Video memory at the same time. This is why you can see some sprite flickering on intense scenes.

Neither it has no sound, because the core it was based on didn't have any sound either. But there might be some exciting news coming up here during the following weeks

[vebxenon]

Wow, so outstanding!!

Thanks again. You are doing a great work! And yes, I'll test the beta once it's published

Regards,

Salva

[ericgus]

Wow neat.. you should put the compiled core up anyway (with obvious work-in-progress warnings/known issues) notice.

[alexh]

Someone dissected the Megadrive soundchip but I believe their work is not 100% suitable for synthesis (Although it looks ok, perhaps a little massage of the ROM table inference)

https://github.com/sauraen/YM2612

This was discussed previously :

http://www.atari-forum.com/viewtopic.php?t=30000

If anyone can help it is Jotego

http://www.atari-forum.com/viewtopic.ph ... 54#p304254

[DrOG]

Whoa! Great news!

Nice work already, thanks in advance!

[Sorgelig]

Code of YM2612 looks very tiny comparing to monster code of the same chip i've saw before...

[mahen]

Keeping my fingers crossed !!
Thanks to all involved !

[farvardin]

That's incredible! Well done and thank you! With sound it will probably be one of the most awaited Mist core

[vebxenon]

Go to test it! https://github.com/mist-devel/mist-bina ... es/fpgagen

[Atmosfear]

Very Impressive. I checked around 10 Games and all did work. Some with graphical Glitches but still enjoyable. Great Work.

[Sorgelig]

So, it's with YM sound now?

[Gehstock]

No Sound , but nice Work

[jotego]

Someone dissected the Megadrive soundchip but I believe their work is not 100% suitable for synthesis (Although it looks ok, perhaps a little massage of the ROM table inference)

https://github.com/sauraen/YM2612

This was discussed previously :

http://www.atari-forum.com/viewtopic.php?t=30000

If anyone can help it is Jotego

http://www.atari-forum.com/viewtopic.ph ... 54#p304254

First of all, I want to thank phoboz for this effort. He is really moving this forward.

I had been in touch with phoboz about this. I was going to finish another core before doing this one but after he has shown the impressive progress I am going to give priority to this. I will release the JT12, a clone of the YM2612, in a few weeks so it can be used on the Megadrive core.

I have some YM2612 chips to take measurement but I do not have a board built for it. I will check out the information on that github that alexh has shared because it claims to document some obscure features. Maybe they have chip measurements. In any case, the plan is to make a first JT12 release based on documentation and the measurements of the YM2151. That should give decent sound. Then, sometime in the future, properly take measurements and release an exact clone.

Note that with the YM2612 the output is analog and with DAC artifacts, which means I cannot take exact measurements of what is going inside the chip. That makes it very difficult to achieve the level of accuracy I got in the JT51. Nonetheless, the YM2203, which is also part of the OPN series, has digital output so I will take measurements of it in the future.

In short, I cannot stand seeing Ghouls'n Ghosts on my MiST without listening to that wonderful melody of the second stage. We shall have sound!

[vebxenon]

Being an alpha, this core is totally impressive!




And wow! what will be the progress? Thanks phoboz!!

PS: Talking about Sega, hope somebody will improve the Master System core, after watching this MD core...

[mahen]

HI ! Extremely enthusiastic about this core Great work ! There are so many amazing games on this platform...
That's clearly something we were all secretly dreaming of

Thanks to the both of you !

[vebxenon]

Oh, and thanks also jotego for your work on the sound

[alexh]

Someone dissected the Megadrive soundchip but I believe their work is not 100% suitable for synthesis (Although it looks ok, perhaps a little massage of the ROM table inference)
https://github.com/sauraen/YM2612

Code of YM2612 looks very tiny comparing to monster code of the same chip i've saw before...

From reading the thread that goes with that VHDL description of YM2612 the design is not 100% complete. The dates on the thread show it is actively being worked on but at least one block "the Accumulator" has not yet been implemented.

[alexh]

I have some YM2612 chips to take measurement but I do not have a board built for it.

The author of that VHDL "sauraen" makes YM2612 boards.

https://www.youtube.com/watch?v=1nM5-QfIv_c

[Slade]

Absolutely brilliant ! I look forward to seeing this mature further.
Thanks for putting in the effort to port this.

[phoboz]

Please also give your thanks to robinsonb5, this would not have been possible without his support!

[Estrayk]

Thanks a lot! really. Congratulations!

[mambrino]

Wooooww! Brilliant! with sound this core will be incredible.
Thanks for your work