MiSTer FPGA - 7800 Core

[RevEng]

 A heads-up that I've been working with some of the MiSTer FPGA devs (Kitrinix and alanswx) on the 7800 core. Mainly I've been the 7800 programming answer-man, creator of various 7800 test programs, co-analyser of problem roms, and guy responsible for updates to the a78 header. I take no credit for any of the VHDL, nor the painstaking hardware analysis being done (but they are using 7800 logic diagrams directly provided to them by no other than Curt Vendel... that guy is still making an impact!) and frankly I'm awed by the level of skill and determination being displayed.

 

It's my pleasure to say the in-progress 7800 core is now freakishly accurate, despite all of the torture tests I've thrown at it. This is not surprising in retrospect, given the attention to detail being thrown into this project.

 

I know real 7800 consoles are getting expensive, especially in certain parts of the world where the 7800 didn't see wide release. A simple de10-nano and 32m memory card may be a good alternative very soon, and if you're interested in any of the other systems, it can be a cost-effective one. (the MiSTer wiki has a good overview, and details on what those other systems are)

 

In case MiSTer FPGA somehow hasn't been on your radar, RMC has a decent intro video...

 

 

[+Gemintronic]

THANK YOU very much for your work.  I'd very much like to use my MiSTer with 7800bas.  My PC and MiSTer are literally a matter of feet from eachother!

[RevEng]

1 minute ago, Gemintronic said:

THANK YOU very much for your work.  I'd very much like to use my MiSTer with 7800bas.  My PC and MiSTer are literally a matter of feet from each other!

Nice, and you're welcome! I'm thrilled to have helped Kitrinix and alanswx with this work. Hopefully you'll get a chance to run the new core soon.

[youxia]

Fantastic news, the lack of 7800 was a significant hole in MiSTer's core library - thanks!

[marauder666]

Lynx coming soon too.

 

The mister is the best piece of modern/retro hardware i’ve ever bought, it never ceases to amaze.

 

[+DrVenkman]

Wow. I think the MiSTer just went to the top of my birthday wish-list this summer!

[+Muddyfunster]

9 minutes ago, DrVenkman said:

Wow. I think the MiSTer just went to the top of my birthday wish-list this summer!

yeah likewise

[+TwentySixHundred]

Awesome stuff, now this is right up my ally ?

[Trebor]

It's a phenomenal team effort.  You guys have achieved, and ultimately providing, something amazing for the community to relish and utilize.  Thank you!

[CPUWIZ]

Expansion port?

[Jstick]

I can highly, highly recommend putting together a MiSTer system, for many reasons (especially to the kind of folks that hang out here).  One of my favourite things ever.

 

The new 7800 core is indeed great.  Ironically, the 2600 core is actually the main weak point for the MiSTer, and I'm really hoping it will get the same love and attention someday.

 

Most of the other arcade, computer and console cores are fantastic if not flawless.

 

 

[swapd0]

I hope that someone port it to the MiST...

[SegaSnatcher]

16 hours ago, RevEng said:

 A heads-up that I've been working with some of the MiSTer FPGA devs (Kitrinix and alanswx) on the 7800 core. Mainly I've been the 7800 programming answer-man, creator of various 7800 test programs, co-analyser of problem roms, and guy responsible for updates to the a78 header. I take no credit for any of the VHDL, nor the painstaking hardware analysis being done (but they are using 7800 logic diagrams directly provided to them by no other than Curt Vendel... that guy is still making an impact!) and frankly I'm awed by the level of skill and determination being displayed.

 

It's my pleasure to say the in-progress 7800 core is now freakishly accurate, despite all of the torture tests I've thrown at it. This is not surprising in retrospect, given the attention to detail being thrown into this project.

 

I know real 7800 consoles are getting expensive, especially in certain parts of the world where the 7800 didn't see wide release. A simple de10-nano and 32m memory card may be a good alternative very soon, and if you're interested in any of the other systems, it can be a cost-effective one. (the MiSTer wiki has a good overview, and details on what those other systems are)

 

In case MiSTer FPGA somehow hasn't been on your radar, RMC has a decent intro video...

 

 

Thanks for your contributions, I've been playing around with a build with latest commits and its quite good already.

[SegaSnatcher]

9 hours ago, Jstick said:

I can highly, highly recommend putting together a MiSTer system, for many reasons (especially to the kind of folks that hang out here).  One of my favourite things ever.

 

The new 7800 core is indeed great.  Ironically, the 2600 core is actually the main weak point for the MiSTer, and I'm really hoping it will get the same love and attention someday.

 

Most of the other arcade, computer and console cores are fantastic if not flawless.

 

 

2600 core could really use a framebuffer toggle for those very problematic games that change the scanline count during gameplay.

[+Karl G]

1 hour ago, SegaSnatcher said:

2600 core could really use a framebuffer toggle for those very problematic games that change the scanline count during gameplay.

Last I saw, it also had issues with a lot of homebrews, since it did not seem to handle early HMOVEs correctly.

[Jstick]

1 hour ago, SegaSnatcher said:

2600 core could really use a framebuffer toggle for those very problematic games that change the scanline count during gameplay.

There is also the matter of co-processor support (i.e. Harmony CDFJ, etc.).  Sorg dismissed the idea of implementing this a year or two ago, but certainly someone else with the knowhow could do so. 

 

Not sure if it would require leveraging the ARM on the DE-10, or (since the original purpose of the Melody ARM was just to replicate DPC etc.) if the co-processor could simply be implemented on the FPGA itself.

[raz0red]

Wow! This is great news.

 

I can't wait to try it on the MiSTer. Thanks for helping make this happen @RevEng.

[+MrZarniwoop]

Is the 7800 core capable of playing 2600 games? If so, is it better at it than the 2600 core?

[RevEng]

The 7800 core is 2600 mode capable, but the devs are literally in the process of hooking that up right now, so it's too early to say.

[orange808]

With a little elbow grease, you can get the MIST 2600 core going on MiSTer.  Although, it would take quite a bit of work to get it 100%.  I dropped the entire thing after I encountered Sorgelig.

 

Looking forward to this 7800 core.  Thanks for the hard work and patience.

Edited March 14, 2021 by orange808

[Trebor]

Just have to say, it was around 8 years ago when RevEng willingly stepped up and assisted with MESS emulation of the Atari 7800, ultimately bringing an accuracy level never seen before under software emulation to the masses.

 

Seems apropos his hand is now involved in bringing the FPGA implementation of the console to a level also never made available before to the masses.  The cycle accurate achievement here is quite astounding.

 

If only he would develop a programming tool for the masses as well.  Actually, do you know what we really need?  A repository for development on the 7800 platform. 

 

"Thanks" just doesn't seem to cut it.  

[+mksmith]

Amazing stuff my friend - enough words literally can't cover your contributions to the 7800 over a long time now. The position the platform now finds itself is due in part to your hard work and effort. Thank you mate ???

[+TwentySixHundred]

Ok so im wanting this badly, although not sure if i should wait or buy it now, then update the cores later. Is there any guides on how to set up the software, like installing the cores and all that jazz? As it's Linux based does that mean you need a Linux OS PC to set it up like the RPi? I have a RPi-4 but this is next level and the Pi i got was pre-configured, so quickly discovered when trying to read/write to the SD my Win10 rig wasn't able to. The only way i could transfer ROMs was by using the Pi interface and a USB stick.

 

Having said all that as an Australian in PAL50 land and due to shipping costs along with wanting an NTSC 7800 this really suits my needs. This way it's the closest experience for me to play and test my homebrew on the real deal. Along with all the other classic console cores this looks to be the ultimate experience ?

[youxia]

39 minutes ago, TwentySixHundred said:

Is there any guides on how to set up the software, like installing the cores and all that jazz? As it's Linux based does that mean you need a Linux OS PC to set it up like the RPi?

You just need to flash the image on a SD card, then set up the Wifi, controller, etc. The updater script will install all the cores for you. It's really rather straightforward, and you definitely don't need a Linux PC (same as for RPi btw).

https://github.com/MiSTer-devel/Main_MiSTer/wiki/Setup-Guide

 

There are enough great cores available now to keep you busy till a proper 7800 release.

Edited March 14, 2021 by youxia

[Skeeter]

I've been running this 7800 beta on my MiSTer and it is damn impressive. Thanks for your work on this @RevEng and all the devs involved. It's great stuff for sure.