Genesis / Megadrive core ported to MiST
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Re: Genesis / Megadrive core ported to MiST
OMG!
I have to test this core the weekend!!!
Thanks!!!
I have to test this core the weekend!!!
Thanks!!!
- jotego
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Re: Genesis / Megadrive core ported to MiST
I have made contact with him. He read the original look-up tables for the sine wave and the exponential functions from the chip. That's critical for accuracy. That part of the information is public now.alexh wrote:The author of that VHDL "sauraen" makes YM2612 boards.jotego wrote:I have some YM2612 chips to take measurement but I do not have a board built for it.
https://www.youtube.com/watch?v=1nM5-QfIv_c
Re: Genesis / Megadrive core ported to MiST
Great news! 
Thanks for all involved and keep up the good work!

Thanks for all involved and keep up the good work!

- jotego
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Re: Genesis / Megadrive core ported to MiST
I have got the first sine wave out of the OPN (FM synthesizer operator of YM2612). This is based on the work Sauraen made reverse engineering the OPN. This is the first milestone. You can check an image of it on my twitter account here
I found some minor errors on Sauraen interpretation of the die picture and send them back to him. So I'm glad I could help debugging the OPN.
For the rest of the YM2612 there are no reverse engineered data so I will just replicate the chip functionality using my own code. Nonetheless, the OPN is critical for sound fidelity so I'm glad we have this part of the circuit exact.
I found some minor errors on Sauraen interpretation of the die picture and send them back to him. So I'm glad I could help debugging the OPN.
For the rest of the YM2612 there are no reverse engineered data so I will just replicate the chip functionality using my own code. Nonetheless, the OPN is critical for sound fidelity so I'm glad we have this part of the circuit exact.
Re: Genesis / Megadrive core ported to MiST
Great news, thank you!
Re: Genesis / Megadrive core ported to MiST
Just tried DuneII, altought it has some graphic glitches, it is well playable. With sound it would be even more fascinating!
Thanks for your fantastic work!!!
Thanks for your fantastic work!!!
Re: Genesis / Megadrive core ported to MiST
Hehe, by any chance, if someone could add 15 KHz support... I know it's not the priority, I'll be patient 

Amiga user non-stop since 1993 
Win 1997-2001 / MorphOS 2002-2005 / Linux since 2005

Win 1997-2001 / MorphOS 2002-2005 / Linux since 2005
- jotego
- Captain Atari
- Posts: 253
- Joined: Wed May 04, 2016 10:02 am
- Location: Valencia (Spain)
- Contact:
Re: Genesis / Megadrive core ported to MiST
Sound update 29-Jan-2017
I found out this week the correct way of calculating FM feedback combining the information Sauraen got from inspecting the die and the data I had collected from YM2151. Now I can make an operator without hacks. By hacks I mean that in JT51 I had to write some nasty verilog lines to fit the output to the original. JT12 is going to have a much cleaner implementation, with a smaller area footprint.
I think I will have the operator fully working with FM feedback during this coming week. That is the second milestone.
Coming milestones:
-FM feedback in operator and channel accumulator
-Phase generator
-Envelope generator
-Register interface and timers
-PCM output and noise
-Testing
-Release
It will probably take about a week to complete each one of them as I have to work on this on my spare time. Bear with me.
I found out this week the correct way of calculating FM feedback combining the information Sauraen got from inspecting the die and the data I had collected from YM2151. Now I can make an operator without hacks. By hacks I mean that in JT51 I had to write some nasty verilog lines to fit the output to the original. JT12 is going to have a much cleaner implementation, with a smaller area footprint.
I think I will have the operator fully working with FM feedback during this coming week. That is the second milestone.
Coming milestones:
-FM feedback in operator and channel accumulator
-Phase generator
-Envelope generator
-Register interface and timers
-PCM output and noise
-Testing
-Release
It will probably take about a week to complete each one of them as I have to work on this on my spare time. Bear with me.
Re: Genesis / Megadrive core ported to MiST
Woohoo, great work 

Amiga user non-stop since 1993 
Win 1997-2001 / MorphOS 2002-2005 / Linux since 2005

Win 1997-2001 / MorphOS 2002-2005 / Linux since 2005
Re: Genesis / Megadrive core ported to MiST
Tried the core briefly and it's super promising! Keep up the good work!
Re: Genesis / Megadrive core ported to MiST
Great!!jotego wrote:Sound update 29-Jan-2017
I found out this week the correct way of calculating FM feedback combining the information Sauraen got from inspecting the die and the data I had collected from YM2151. Now I can make an operator without hacks. By hacks I mean that in JT51 I had to write some nasty verilog lines to fit the output to the original. JT12 is going to have a much cleaner implementation, with a smaller area footprint.
I think I will have the operator fully working with FM feedback during this coming week. That is the second milestone.
Coming milestones:
-FM feedback in operator and channel accumulator
-Phase generator
-Envelope generator
-Register interface and timers
-PCM output and noise
-Testing
-Release
It will probably take about a week to complete each one of them as I have to work on this on my spare time. Bear with me.



Just a computer and videogame lover
- Atari Jr 2600 clone
- Atari 7800 Peritel
- Atari XEGS
- Atari Lynx II
- Atari Jaguar
- MiST Board

- Atari Jr 2600 clone
- Atari 7800 Peritel
- Atari XEGS
- Atari Lynx II
- Atari Jaguar
- MiST Board
Re: Genesis / Megadrive core ported to MiST
Wow!! it's impresive. Great work!!
Re: Genesis / Megadrive core ported to MiST
Any news on progress? 

Just a computer and videogame lover
- Atari Jr 2600 clone
- Atari 7800 Peritel
- Atari XEGS
- Atari Lynx II
- Atari Jaguar
- MiST Board

- Atari Jr 2600 clone
- Atari 7800 Peritel
- Atari XEGS
- Atari Lynx II
- Atari Jaguar
- MiST Board
Re: Genesis / Megadrive core ported to MiST
https://github.com/jotego/jt12/tree/656 ... 31/fpgagen
Sound quality is Great but Core Unstable(Loading Error)
Sound quality is Great but Core Unstable(Loading Error)
Last edited by Gehstock on Fri Feb 24, 2017 7:40 pm, edited 1 time in total.
Re: Genesis / Megadrive core ported to MiST
Wow, outstanding!!!
I'll try it later



I'll try it later

Just a computer and videogame lover
- Atari Jr 2600 clone
- Atari 7800 Peritel
- Atari XEGS
- Atari Lynx II
- Atari Jaguar
- MiST Board

- Atari Jr 2600 clone
- Atari 7800 Peritel
- Atari XEGS
- Atari Lynx II
- Atari Jaguar
- MiST Board
-
- Atari freak
- Posts: 57
- Joined: Wed Sep 29, 2010 1:27 pm
Re: Genesis / Megadrive core ported to MiST
Wow! This is seriously very cool, thanks to everyone involved and especially jotego for his amazing Yamaha synth models!
Re: Genesis / Megadrive core ported to MiST
Awesome! Can't say how happy I am.
Thank you!
Thank you!
Re: Genesis / Megadrive core ported to MiST
This is not my work, thanks must go to jotego and phoboz
Re: Genesis / Megadrive core ported to MiST
Very nice, with this core:"clkfeo con warnings.rbf" music is closer than Real Sega Genesis/Megadrive.
There are some glitch and with Sonic game, rings fx are different but wonderful !!!
There are some glitch and with Sonic game, rings fx are different but wonderful !!!
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
http://www.amedia-computer.com
Re: Genesis / Megadrive core ported to MiST
the core file name translates to "ugly clock, with warnings"
I shall try this when I get a chance...

Re: Genesis / Megadrive core ported to MiST
Outstanding result, unfortunately I can not test it now (my MIST is far away, I lent it to my friend, and he didn't bring it back yet). Keep up the good work, have a nice weekend!
Re: Genesis / Megadrive core ported to MiST
I tested yesterday the "clk nuevo mio sin warnings.rbf" (Actually I don't know what are the differences between the cores) core. Sound needs still work in pitch, speed and notes, but that's outstanding
. Core is still unstable, but wow! 
Thanks Phoboz and Jotego!
Regards,
Salva


Thanks Phoboz and Jotego!

Regards,
Salva
Just a computer and videogame lover
- Atari Jr 2600 clone
- Atari 7800 Peritel
- Atari XEGS
- Atari Lynx II
- Atari Jaguar
- MiST Board

- Atari Jr 2600 clone
- Atari 7800 Peritel
- Atari XEGS
- Atari Lynx II
- Atari Jaguar
- MiST Board
Re: Genesis / Megadrive core ported to MiST
Guys this is great and all but i cant use it as my set up is a 15khz rgb system can somebody please add the scandoubler disabled option to this core?
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- Atari freak
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- Joined: Wed Sep 29, 2010 1:27 pm
Re: Genesis / Megadrive core ported to MiST
Oh is it not 15khz enabled? That's a shame, I too am using my MIST on a CRT TV.