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Good thought, and thanks for the kind words. Here is what I know, and what I haven’t tried:

• The Neo Geo’s screen width is fixed. It draws 320 pixels across (some TVs show about 304), and no register makes it wider. The CPS-1 arcade original draws 384, so the port has to fit that extra 64 pixels somewhere.
• There is a per-sprite horizontal shrink. In theory it could squeeze a whole scene by about 5/6 so everything fits. But I haven’t tried it. It would soften the graphics, cost extra work every frame, and wouldn’t apply to the text layer.
• So far I’ve fixed the cropping scene by scene instead. That’s why only a few places are affected, such as the ending credits and the initials screen. I’m still working on those.

If you’ve seen another Neo Geo game stretch or squeeze its picture horizontally, tell me which one and I’ll look at how it does it.

Thanks for looking so closely, and for the screenshot. That’s the file 222-c8.c8 from the FBNeo set (samsho4.zip), not from the real cartridge layout.

• The 4 bytes at the end (5A ED 74 53) are almost certainly a checksum filler. FBNeo only runs a set it already knows by name and CRC, so the zip is disguised as Samurai Shodown IV. The padding and the last few bytes are there so the files match the sizes and CRCs FBNeo expects.
• They do nothing on real hardware. The 68000 and the Neo Geo graphics chip never read them. They aren’t game code or data, and you don’t need to burn them.
• The zeros are the same story. They only fill the file out to the size FBNeo expects, and the cartridge never reads them.

For EPROMs, please don’t use the FBNeo zip. The real contents are in the .neo build:

• C ROM: two 4 MB lanes, C1 and C2, completely full with no padding.
• V ROM: 16 MB. Unused space at its end can be left unpopulated.
• P ROM: 1 MB.

Not yet confirmed: the exact used size of each ROM, and how much of the V ROM’s end can be dropped. I’ll check these and post a list of the minimum chip size per ROM, so you only buy and burn what is needed.

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Gracias por mirarlo con tanto detalle y por la captura. Ese es el archivo 222-c8.c8 del set de FBNeo (samsho4.zip), no el de un cartucho real.

• Los 4 bytes del final (5A ED 74 53) son casi seguro relleno para el checksum. FBNeo solo ejecuta sets que ya conoce por nombre y CRC, así que el zip se disfraza de Samurai Shodown IV. El relleno y esos últimos bytes están para que los archivos coincidan con los tamaños y CRC que FBNeo espera.
• En hardware real no hacen nada. Ni el 68000 ni el chip gráfico de Neo Geo los leen. No son código ni datos del juego y no hace falta grabarlos.
• Los ceros son lo mismo. Solo rellenan el archivo hasta el tamaño que pide FBNeo y el cartucho nunca los lee.

Para las EPROM no uses el zip de FBNeo. El contenido real está en el build .neo:

• C ROM: dos carriles de 4 MB, C1 y C2, completamente llenos y sin relleno.
• V ROM: 16 MB. El espacio sin usar al final se puede dejar sin poblar.
• P ROM: 1 MB.

Sin confirmar todavía: el tamaño usado exacto de cada ROM y cuánto del final de la V se puede quitar. Lo reviso y publico una lista con el chip mínimo para cada ROM, así solo compras y grabas lo necesario.

Hi, and greetings back to Argentina! You’re right, and thank you for trying it on real hardware.

The files in the current release are padded. The sound sample ROM (V) is stored as 16 MB, but only about 9 MB of it holds real data. The rest is filler. The graphics ROMs (C) are about 8 MB and completely full, so they can’t be trimmed that way. The program ROM (P) is 1 MB, and the S and M ROMs are 128 KB each.

Removing the filler is on my list. I haven’t done it yet, so I can’t give you exact sizes or a date. Even after the filler is gone, the sample data is a bit over 8 MB, so it still won’t fit a small cartridge without more work. I’ll post the new sizes in a devlog when I have them. Since you only have original cartridges and no flash cart, tell me which EPROM or mask ROM sizes your boards take and I’ll aim for those.

¡Hola, y saludos a Argentina! Tienes razón, y gracias por probarlo en hardware real.

Los archivos de la versión actual tienen relleno. La ROM de samples de sonido (V) está guardada como 16 MB, pero solo unos 9 MB tienen datos reales. El resto es relleno. Las ROMs de gráficos (C) son de unos 8 MB y están completamente llenas, así que no se pueden reducir así. La ROM de programa (P) es de 1 MB, y las ROMs S y M son de 128 KB cada una.

Quitar el relleno está en mi lista de pendientes. Todavía no lo he hecho, así que no puedo darte tamaños exactos ni una fecha. Aun sin el relleno, los samples ocupan algo más de 8 MB, así que todavía no cabría en un cartucho pequeño sin trabajo extra. Publicaré los nuevos tamaños en un devlog cuando los tenga. Como solo tienes cartuchos originales y no flash, dime qué tamaños de EPROM o de ROM de máscara aceptan tus placas y apuntaré a esos.

Hi! Thanks for asking, and for owning real MVS hardware, that's exactly the audience this is for.

Short answer: it's designed as an MVS cartridge, but I have NOT tested it on real hardware yet, so I can't promise it works on a real board.

What I can tell you about the ROM layout:

- Program (P1): 1 MB, no bank switching

- Fix layer (S1): 128 KB

- Z80 sound program (M1): 128 KB

- ADPCM samples (V): about 9 MB used

- Graphics (C1/C2): 4 MB each (8 MB total), exactly full

So it's a normal-sized cart and doesn't need anything exotic. It runs entirely on the 68000 and the stock Neo Geo graphics chips. Nothing depends on an emulator.

What you would need is a way to put those ROMs on a cart: a flash/multi-game MVS cart or a custom board. I haven't built one, so I can't tell you which will work.

The game also has the standard soft DIP menu in the MVS Test menu, so it behaves like a real MVS game.

Right now the download is the .neo file (for Geolith / MiSTer / NeoSD) and an FBNeo set. A separate ROM set for real cartridges is something I want to do, but it isn't ready or tested. If you try it on your hardware and tell me what happens, that would help a lot.

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Hola! Gracias por preguntar, y por tener consolas MVS originales: es justo para quien está pensado.

Respuesta corta: está diseñado como cartucho MVS, pero TODAVÍA NO lo he probado en hardware real, así que no puedo asegurar que funcione en una placa real.

El diseño de las ROMs:

- Programa (P1): 1 MB, sin cambio de bancos

- Capa fija (S1): 128 KB

- Programa de sonido Z80 (M1): 128 KB

- Muestras ADPCM (V): unos 9 MB usados

- Gráficos (C1/C2): 4 MB cada uno (8 MB en total), completamente lleno

Es un cartucho de tamaño normal. Funciona solo con el 68000 y los chips gráficos estándar de la Neo Geo; no depende de ningún emulador.

Lo que necesitarías es una forma de grabar esas ROMs en un cartucho: un cartucho flash/multijuego para MVS o una placa propia. Yo no he fabricado ninguno, así que no sé decirte cuál funcionaría.

El juego también tiene el menú estándar de DIP por software en el menú Test de la MVS, como cualquier juego MVS.

Ahora mismo la descarga es el archivo .neo (para Geolith / MiSTer / NeoSD) y un set para FBNeo. Un set de ROMs para cartuchos reales es algo que quiero hacer, pero no está listo ni probado. Si lo pruebas en tu hardware y me cuentas qué pasa, me ayudaría muchísimo.

Yes in the future, #1 get speed and camera timing correct #2 Get AES version setup and running with few extras #3 CD Version with all the bells and whistles this will take some time

Thanks for testing this on real hardware, and the detail about the credits screens helped a lot. This beta is built for MVS hardware, and it uses the MVS-only backup RAM as working memory. The AES doesn’t have that RAM, so it shows the disclaimer pages and then can’t continue. That’s a limitation of this release, not your SD card. An AES-compatible version is planned. Thanks for the report.

I’ve checked the .neo file against the format and it’s valid, so I think it’s a setup or firmware issue. What firmware version is your NeoSD Pro on, and do other .neo games show up? If you can try the file in the root folder of the SD card and send me what the menu shows, I’ll dig into it.

Remember, this is just a beta. Think of it as a preview, not the finished game. There are still plenty of bugs to fix, and I’ll hold off on further releases until they’re ironed out, but I do plan to put out an updated version soon. Thanks for all your support!

Good point, and you’re right about the CPS-1. Capcom designed those games for 4:3 CRTs, so the pixels aren’t square.

The screenshots are raw 320×224 captures straight from the emulator, so they show the unscaled framebuffer, not what you’d see on a real screen. The Neo Geo outputs 320×224 and is also meant to be shown at 4:3, so on a CRT or with the aspect ratio set to 4:3 in MAME it should look correct, not squished.

The Neo Geo’s 320-pixel width is narrower than the CPS-1’s 384, so the game uses a window that follows the camera. That crops a little of the sides compared with the arcade, and I’m working on keeping it as faithful as possible.

Thanks for pointing this out. I’ll add a note about the aspect ratio to the page so it’s clear how the game is meant to be displayed.

This is the MVS version. The AES version will have plenty of options. The goal right now is stability and fixing the small imperfections so it plays as close to the original as possible. The CPS-1 and the Neo Geo share the same processor, but they handle graphics, sound and everything else very differently.

I understand, but that’s outside the scope of the project right now. The main focus is getting this version stable and running at the original’s native 30 fps. It currently reaches about 27 fps, so you may notice some lag. Closing that gap is the top priority at the moment.

Please clarify what you are asking please?

Its in development

Its in development