I started this week trying to get System 16B games working, but I came across the i8051 MCU again. This MCU is used in many arcade games, and I have already faced it in the past. There are no good open-source cores for it. At least, not good from our retro point of view. I haven't been able to make it work reliably so far.
Ace contacted me about a sprite issue in the Contra core, and by reviewing the implementation, we found th...
2021-07-09 15:58:13 +0000 UTC View PostMiSTer users: copy beta.zip to games/mame
This week we have three classic titles. Passing Shot was my tennis school as a kid and Alien Syndrome was on magazine covers everywhere. And Time Scanner is one of the best-known pinball titles.
Note that for Passing Shot, you will have to look in the Alternatives folder.
After this, we have almost covered all System16A games. There are three titles le...
2021-07-02 17:14:29 +0000 UTC View Post
The SEGA System 16 isn't a single arcade game architecture. It had two major versions: 16A and 16B and a close ancestor known as pre 16A. But if you look closer, you will find more variations.
There were boards with unencrypted CPUs, but there were encrypted ones too. And among them, there were several options too: FD1089A, FD1089B (Action Fighter, Sukeban...) and FD1094 (some 16A games, 16B) for the M68000 code. Encryption wor...
2021-06-25 17:01:37 +0000 UTC View Post
The long story of the M68000 related bug finally came to a happy ending. Long story short, Blackwine identified the instruction that broke Shinobi and Ijor -the M68000 module author- suggested the read-modify-write cycle could be wrong in the glue logic.
Normally, a CPU takes control of the data bus to read or write, not both. However, the M68000 provides a special case for an atomic read-modify-write that doesn't release the b...
2021-06-18 16:07:53 +0000 UTC View PostThe CPS2 core still has several issues which are all likely linked to a bug in the M68000 CPU. I will eventually find and fix the bug, but it can still take from days to a few weeks.
If I release CPS2 as it is, there is a major problem with Mars Matrix and with Gigawing's final boss.
I haven't been able to run the speed comparison tests yet, but that worries me less as it will be easy to correct once we have the spe...
2021-06-12 07:29:55 +0000 UTC View Post
Hi all, I have too many news this week!
-New System 16 beta with four games added: Wonder Boy 3, Phantasy Zone, Action Fighter and Alex Kidd. Note that WB3 is in the alternatives folder only for now.
-For MiST and Sidi, just use the attached files as usual
-For MiSTer, beta files are now stored in 2021-06-11 15:18:25 +0000 UTC View Post
(español abajo)
Last week's I held a video meeting with the Patreon directors. To summarize it in a line, I want to increase the quality and quantity of the work. For this, I will try to leverage both the community and full time hires. I am about to make an offer to the first JT employee to work full time on development. At the same time, I bring today a new tool that should enable more community contributions: a cheat engine....
2021-06-04 17:04:22 +0000 UTC View Post
(español abajo)
We finally close the CPS2 beta series this week with four titles:
I am very thankful to all of you for supporting the development of this core. However, I must say that it is still not perfect. A bug makes Mars Matrix run at a crazy speed and breaks Gigawing fi...
2021-05-28 18:31:11 +0000 UTC View Post
(español abajo)
I have given a big push to the Konami titles this week. I have applied many of Furrtek's discoveries on the custom chips. As a result, many graphic glitches have gone away in Combat School and Labyrinth Runner. In addition, the custom chip involved in the barrel calculation (Contra 3D phases) is now part of the core too, so bar...
2021-05-21 15:40:25 +0000 UTC View Post(español abajo)
This week's update comes with a ton of internal changes. First, the SDRAM is now operated at bursts of 8 bytes, so graphics information is transferred in a single request. Together with other improvements, this change has boosted the number of sprites per line, and the X-Men COTA start screen is now correctly displayed.
I was misreading a part of the schematics related to bus timing. That is corrected too...
2021-05-14 15:45:13 +0000 UTC View Post(español abajo)
I had fixed, improved and strengthen many core features not just during the week but during the last two weeks. So, I was looking forward to this update. But, in the tests before bringing this to you, I found a couple of graphics issues that could also be hiding elsewhere. I didn't even get to pass the final files to the JTAlpha team for testing. I had to make the painful decision of rolling back to a safe plac...
2021-05-07 19:12:29 +0000 UTC View Post
(español abajo)
This has been another busy week of catching bugs, trying to close the core development. There are four types of problems left:
1. Graphic glitches due to SDRAM congestion
2. Raster and row scrolling effects not working well together
3. Odd behaviours that could point to a bug in the M68000 CPU module
4. Rendering of a wrong tile in some specific scenes
I have re-written the SDRAM c...
2021-04-30 14:52:50 +0000 UTC View Post
(español abajo)
It has been a very intense week as I am ironing out the little things pending in the core. They are little, but they are the toughest ones!
The only worrying one is Gigawing because, in a couple of scenes, there is a moment when the SDRAM fails to deliver all the sprites, and some lines show glitches.
As some people reported that Progear was too slow, I have disabled the CPS-A chip DMA. This will sp...
2021-04-23 15:54:50 +0000 UTC View PostYou were expecting more shooters, and here you go:
-Progear: this game has awesome graphics. It reminds me of Studio Ghibli art. The gameplay is also great.
-Eco Fighters: this horizontal shooter has an interesting mechanic because of the rotating cannon, similar to Forgotten Worlds. The Megaman team designed it.
I will catch with you next Friday!
Español
Esperabas más tiradores, y aqu...
2021-04-16 17:52:39 +0000 UTC View Post
(español abajo)
I started on Patreon 2 years ago, after my Ghosts'n Goblins core was ported to MiSTer. When I saw the coverage that Smokemonster made for it on his YT channel, I thought it was worth developing more systems. Two years later, I have published a ton of stuff: individual chip modules, single arcade boards and multi-game arcades. And all this has been possible because of your continuous support. This week we hit th...
2021-04-16 14:49:45 +0000 UTC View PostWhat would you like the next JTFriday to be about?
2021-04-10 07:42:28 +0000 UTC View Post
(español abajo)
We finish three series of games this week:
-Dungeon&Dragons, by adding Shadow over Mystara
-19XX, by adding 1944
-Street Fighter Alpha, by adding the third game
Plus Janpai Puzzle Choko, a title in Japanese, but you don't need to understand the language to play. Give it a go!
Grego2d has made a special MR...
2021-04-09 14:58:51 +0000 UTC View Post
(español abajo)
I've been working non-stop to find the bug in the QSound chip producing the distortion, but I still haven't got it. So there is no CPS2 update this week.
To make up for it, and because I know some people miss 80's games, I am offering you one of my personal favourites this week: Shinobi.
By the way, I want to thank FunkyCochise and AMoore2600 for lending me their System 16/18 ...
2021-04-02 16:20:47 +0000 UTC View Post
(español abajo)
This week comes with an incredible new bunch of games. I cannot pick the main title! We have the second game in the Darkstalkers series (Revenge), which brings more crazy spooky fights. I had been asked about Dimahoo for several weeks, and I think it's quite solid now, so there you go! Then, we start the Marvel series with X-Men, Children of the Atom
2021-03-26 16:31:34 +0000 UTC
View Post
(español abajo)
There are several game series on CPS2, and we continue this week with the Alpha one: Street Fighter Alpha 2 (including Zero 2 Alpha) is visiting us today. We finally have all the characters that appeared in Super Puzzle Fighter 2 in their original games available. CPS2 is full of cameos and references between the games, so keep an eye open when you play.
We have a mix of quiz and dating simulation with Qu...
2021-03-19 17:05:00 +0000 UTC View Post
Please get the files from the latest beta post
(español abajo)
My first core after starting Patreon was 1942. It took me about two months to complete it. About two years later, I can deliver new cores much more quickly, but the feeling towards these games hasn't changed. I am very glad to see 19XX joined the club of FPGA-converted games!
The other big title for this week is Darkstalker...
2021-03-12 16:59:55 +0000 UTC View Post
PLEASE GET THE FILES FROM THE MOST RECENT BETA POST
(español abajo)
Development of the CPS2 core has progressed. Some GFX glitches are gone now (formerly visible in CSCLUB/MPANG), and there is now support for 16MB GFX games. These are the titles for this week:
-All 16MB version Mighty! Pang
-Puzz Loop 2
-Alien vs Predator
AvsP is one of the most popular titles in this system. It is fully playa...
2021-03-05 16:47:04 +0000 UTC View Post
PLEASE GET THE FILES FROM THE MOST RECENT BETA POST
(español abajo)
Now that the basic CPS2 architecture is in place, it is time to add more games to the core. CPS2 games could have up to 32MB of graphics ROM; for this week, the focus has been games of 8MB. These are the titles:
-Street Fighter Alpha, at last, we have the original version working on MiSTer
-CAP...
PLEASE GET THE FILES FROM THE MOST RECENT BETA POST
(español abajo)
This week we have achieved a major milestone: on-the-fly ROM decryption, just as the original system does.
CPS2 games are encrypted by shuffling bits and exoring with the keys over and over again. The encryption key is 64-bit wide, and it gets merged with the address of the data to generate a second key. There are many sta...
2021-02-19 17:00:55 +0000 UTC View Post
(español abajo)
I started on FPGA retro developments with a Yamaha YM2151 module: the most important chip for arcade games. I made hundreds of measurements, and I designed the FPGA counterpart -JT51- to match those measurements.
But there were two things I couldn't measure: the noise channel and the low-frequency oscillator (LFO). I made an implementatio...
2021-02-12 20:57:23 +0000 UTC View Post
NVRAM
After some headache and too many debugging hours, we finally have NVRAM support for MiSTer CPS1 and CPS1.5 cores.
All CPS1.5 cores use NVRAM instead of DIPs to keep the configuration. From the CPS1 set, Pang! 3 uses NVRAM too, although it seems that not all versions do.
NVRAM requires both the new RBF and also the new MRA files. Everything will be taken care of by the automatic updater. <...
2021-02-05 17:55:55 +0000 UTC View Post
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<...
2021-01-31 10:26:45 +0000 UTC View Post
Please find the files attached. Unzip the file to the _Arcade folder in your SD card, then run the update_all script on MiSTer.
Sorry for the long wait! I am proud to announce the first beta of the CPS2 core for MiSTer and MiST/SiDi!.
Super Puzzle Fighter 2 Turbo, one of the most popular games in the system is our opening title. This cute game combines the Nightstalker and Street Fighter 2 series...
2021-01-29 17:28:44 +0000 UTC View Post
A typo broke the volume balance in the last CPS1 update, but I thought it was something else. So I started looking at ways sound may not have been accurate. Eventually, I found the typo, I increased accuracy, and I re-balanced the volume in all cores. 20 cores have been updated.
NOTE: CPS1/CPS1.5 files in the repository operate at 48MHz. Find attached versions at 96MHz.
YM2151/YM2...
2021-01-15 22:17:19 +0000 UTC View PostI know you are tired of SDRAM trials. So am I. So this will be the last one.
I have built a memory test, which uses the SDRAM logic I use on my cores (including CPS). There are two versions: 48 MHz, and 96 MHz. Both will show a green screen until a problem is detected. Then, the display will turn red and stay red.
Each time screen goes from dim to bright and back to dim; a test cycle has been completed. Only the fir...
2021-01-08 17:27:15 +0000 UTC View Post
