CPS1/CPS1.5 Accuracy
Accuracy of the core; that is what we all want.
I was concerned about the speed of the CPS1 core for a long time. But I needed a reliable way to measure it. I bought the tools to replace the ROMs in an SF2 PCB with my test code. Then, I contacted Grego2D (the author of Final Fight Anniversary Edition) and asked him to write the test code.
The test runs a counter in a loop and shows how many counts can be done in a frame.
The results were appaling: the core was 20% slower in normal mode and 20% faster in turbo mode. MAME, in comparison, is 45% faster. So we were doing better than MAME, but a 20% error was not acceptable.
I corrected the DMA code and got to 15%. Then, I checked over and over the bus wait logic. And, finally, I got it down to 0.08%. Yes, 0.08% error in a demanding test. I think a verified figure of this magnitude deserved a post and a core update.
We still have to test other DMA cases, which may explain the remaining 0.08% difference. But be sure that we will nail this.
Please run the update tool, or look for the files in jtbin. This update also fixes other reported issues.
Comments (59)
Anyone else using their F5 key too much today?
0.08%.. ?? Isn’t the tolerance level of sync larger than that error margin?... not that I’m complaining :)
Yes, I think the oscillator drift in the old PCB accounts for some of that discrepancy.
I was wondering if you could take a look at Sagat from Street Fighter 2 Champion Edition and Hyper Fighting, his character is glitched on the right side of the screen. Right on his stomach area. I wish I could show pictures
Hi Joseph, I think it is fixed now. Please run the updater.
By the way, this project is so cool and I love all of your work
enough is enough my friend! it's too perfect!
I love the rigor of these unit-level tests, which raises the whole community (and accuracy) up. Keep you the great work!
Awesome work would be an understatement.... Truely happy to be supporting your work one way or another via Patreon and of course, definitely be happy to be able to enjoy the fruits of your dedication and passion!
amazing!
Madness! In the best possible way :) keep it up, JT
Could the 0.08% just be within the measurement limits? Great job man!!
legendary :) thanx for the hard work
outstanding work, jotego! i have wondered about the speed difference compared to a PCB as well, and from the beginning's of your CPS1 core, i noticed the game speed in SF2 was a little off. mind you, it wasnt a deal-breaker, and i could still beat SF2. but, the game just felt a tad "off" from the arcade. this is Exactly what i was hoping for and is a Very big deal. you have made the most accurate way to play CPS1 on modern TVs. the MiSTer provides a more accurate way to play CPS1, even compared to a 5GHZ super computer with the latest and greatest GPU, and is now only beaten by someone who has a PCB. i very much hope the same accuracy can be achieved with CPS2.
I’m running a cps1 ghouls n ghosts in a Namco Exceleena ll via a 25” toshiba/Nanao....I would never be able to discern a variance. Amazing.
This is awesome. I'll have to check out Ghouls 'n Ghosts speed.
0.08%. What are we? Cave men? Lol great job. Amazing progress.
Absolutely amazing work as always! We are lucky to have you on the project!
I love your dedication to accuracy! 💯
0.08% ! impressive very low, going from 20% faster or slower to 0.08% is a major improvement
This is why you are the best MiSTer core maker out there.
すごい！！！
Thank you!
Would be great to work with Digital Foundry as they just posted a MiSTer video and spoke about testing performance in future.
I suppose he showed that footage of MAME to make people think. That is good.
great work!
Jotego has done it again! :) Great job!
Impresionante!! We’re really lucky to have you on board with the Mister! Keep up your amazing work 🙌🏼
Thanks Jotego 🙏😇
That’s an impressive work 👍
That's why we count on you. Nicely done.
Thanks for the great job
PERFECT Blanks does howl and raises fist!
This honestly makes me happier than the CPS2 release... and that is awesome! Strider and Ghouls n Ghosts are the games of my childhood. Thank you Jotego and Grego 👍
There were some slow scenes in those games before. I believe both will be near perfect now.
Congratulations. Keep up the good work.
Congratulation for the perfection!!! Thank you so much for your work
Awesome work man, congrats and many thanks to you and Grego for the huge amount of work!
Played through SF2 World Warrior yesterday and then today with update and i hope its not rose tinted glasses but it felt like a much better playthrough, special moves seemed more reliable, might be me but great work!!!
Absolutely Incredible. Thanks to you and Grego for your hard work!
God-tier accuracy
Outstanding :)
This corrects the speed in SFII Turbo? edit: I just saw your posts on the issue thread. This is a BIG improvement then!! Very important fix. Thank you :))
Impressive, The quality of your work is absolutely amazing! Thank you very much!
Genial JT!
Nice
Great work, and thanks to Grego as well!
This is excellent news! Awesome work on making this more accurate Jose, and thanks Grego2D for creating the test.
Phenomenal work!
Awesome work!
Your dedication to accuracy is incredible. Well done and thank you!
Good work Jose, Thank you☺️
Amazing! This gets better and better!
Well done and thank you for this, great job 👍
Excellent! Thanks a lot 🤩
You are incredibly dedicated! - thank you for letting us benefit from that :)
Great! Well Done :)
This is good news chico! Good job! :)
impressive !