S-PPU and the V9990 (also MSX3)

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Pokun
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S-PPU and the V9990 (also MSX3)

Post by Pokun »

According to Kazuhiko Nishi, the founder of ASCII Corporation and creator of the MSX computer standard and who is currently working on the MSX3 after all these years (not kidding), the V9990 video chip is the basis for the S-PPU in the Super Famicom. Anyone heard this before? This was news to me anyway if it is true.

After some fans asking him to include the Yamaha V9990 VDP in the MSX3 standard (in a rude fashion) he responded sharply that he won't include it due their history together:
Nishi wrote: Yamaha fail to deliver 9978(later 9990) in time for MSX3. That was the reason name changed to Turbo R. We had only fast CPU. Then Pana used delayed Video chip without our consent saying extra fanctions will be machine depanding non MSX functions.

then by the side, yamaha gave the knowhows of video chip to nintendo and created super famicom without telling us anything. Was that a fair business practices? We dont think so. So we decided not to use 9990 for ever.

we will support uptill 9958 and any future expantion will be strong sprites and 2K and 4K high speed video drawings. All the yamaha patents are expired and now free to use. anyone can copy 9990 but 6 to 12 month work and no resources to do and dont want to delay msx3 launch.
Kazuhiko Nishi on Twitter 2022-01-14


Some quick background: the MSX used the well-known Texas Instrument TMS9918 VDP as its video chip (which were also used by many other systems such as ColecoVision, Sega's console/computer and probably also partly inspired Nintendo's PPU), and ASCII ordered Yamaha to create an upgraded version of it when they updated the standard to MSX2. The result was the Yamaha V9938 MSX-VIDEO, and then they did so again when upgrading to the MSX2+, which was a very small update with the V9958 (basically only adding another scroll axis and a few new modes). Finally they ordered the V9978 from Yamaha for the upcoming MSX3, but Yamaha failed to deliver and they changed the name of the MSX3 to MSX Turbo R (as Nishi said above) due to this, since they only had a new faster CPU (R800) and more RAM for this new MSX standard, not a new VDP as promised. Yamaha finalized the new VDP but it was rejected, so they stripped it down, removing its backwards-compatibility with the V9958, and renamed it the V9990. They used it in some computer video cards I think, and the Dutch company Sunrise made the GFX9000 MSX cartridge (1994), allowing to use it as an external video card for any MSX, and a few other companies released similar products using the chip. A few MSX "homebrew" games that uses it do exists.

Thoughts about this (or even the MSX3)?
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TmEE
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Re: S-PPU and the V9990 (also MSX3)

Post by TmEE »

I have had some experience with V9990 and I couldn't see anything whatsoever in it that indicated anything like what is in SNES. It is more or less enhanced original TMS VDP+the earlier Yamaha upgrades with a simple blitter attached on top and some other bitmap orientated features, it certainly didn't go into the territory of video game chips that need scroll layers and sprites, but firmly into computer stuff where pixel manipulation is paramount.

EDIT: If anything, he should be angry with Sega, as Yamaha is the one who made the VDPs for Sega and there is clear heritage from the TI chip seen in MD and SMS chips.
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Re: S-PPU and the V9990 (also MSX3)

Post by Pokun »

Neither the V9938 (MSX2 VDP) nor the V9958 (MSX2+ and Turbo R VDP) are very gaming oriented compared to the Sega Mark III VDP. The V9938 only added vertical scrolling (very computery since you often scroll text vertically) and slightly better spriting (8 sprites/scanline instead of 4 and multicolored sprites instead of monochrome), and that was basically it. Most of the other new modes were for bitmapped graphics or the new spriteless 80-column mode. It's even said that Nishi didn't want the MSX to be marketed as a gaming platform (which I think would be a bad business decision) and those new sprite features are rumored to have been added by Yamaha on their own accord.
V9958 finally got horizontal hardware scrolling, but not much else (that's why it's called MSX2+).

But the V9990 supposedly had the backwards-compatibility of the previous VDPs removed, which is why it changed name from V9978 to V9990 since it's no longer a TMS9918 derivative. ASCII allowed this so that Yamaha were able to sell it and cover some of their losses for developing it.

Nishi is supposedly angry with them because they went behind his back and selling the info to Nintendo that resulted from their research coming out of their deal with Yamaha. There is not reason for him to be angry with Sega because of their deal with Yamaha regarding an unrelated TMS9918 derivative.

I don't think the S-PPU is based on the V9990, but I guess some technique might had been used or something.
The most obvious features they seem to have in common are the 15-bit RGB colors (32 768 colors) which is quite a distinguishable feature of the SFC (and the GBC) and the 125 sprites/frame limit which is close to the SFC's 128.
I don't know hardware enough to make anything but vague speculations though.


Nishi said they are developing the V9998 for the MSX3 which will be better than the V9990. The MSX3 will be a Raspberry Pi-like device on a board with FPGA and an ARM processor. The MSX-backwards-compatibility will be on the FPGA while the ARM is to make it a bit more modern.
It seems he is also releasing it in MSX cartridge form which allows upgrading a previous MSX to MSX3. He also release the keyboard and the new MSX3 Engine chip for people that wants to build their own things with it.
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Re: S-PPU and the V9990 (also MSX3)

Post by TmEE »

15bit output wouldn't mean anything, it just is some more resistors for the DAC of a video signal and all the extra memory bits to hold the expanded palette info + wider bus to that memory.
I really wonder what is what is thought to have gone into SNES, because I absolutely cannot see anything that works the same way and is clearly inspired or borrowed by one-another.

I am not aware of any Yamaha and Nintendo cooperation either, Yamaha didn't produce any chips for Nintendo while Yamaha produced most chips for Sega and you see YMxxxx markings on decapped parts... SMS1 and MD are all Yamaha parts, Saturn is half Yamaha, half Hitachi. (SMS2 and GG use NEC made parts). A lot of their arcade hardware is all Yamaha parts too.
Pokun
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Re: S-PPU and the V9990 (also MSX3)

Post by Pokun »

Some people even think he might have mixed up Nintendo and Sega, but there is really nothing obviously V9990-like in the MD VDP either, is there (aside general likeness to the TMS9918 design)? The MD was also already released 1988 while the V9978 wasn't presented until 1990 and had probably yet to be rejected.

The V9990 is often said to be SFC-like in capability, and the dates matches the SFC development, so I thought it wouldn't be too surprising if Nintendo and Ricoh at least looked at Yamaha's work when finalizing the S-PPU after axing the backwards-compatibility with the Famicom PPU.
https://www.msx.org/wiki/MSX_turbo_R wrote: In pattern mode, it was capable of Super Nintendo class features. Multi layers, 16k patterns, several palettes, 128 sprites, a maximum of 16 sprites per scanline. So basically a SNES but with no mode7.
I'm not sure about "basically a SNES without mode 7" but it is a VDP of similar capability. But I guess it might just be vaguely similar because they are both video chips of the same 16-bit era from the early '90s.
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Re: S-PPU and the V9990 (also MSX3)

Post by lidnariq »

Doesn't seem particularly similar.

Has two video modes, one very approximately like mode 1/the 256px Megadrive mode (but only two layers / no OPT / but 15bit per palette entry) ("P1"); one very approximately like mode 5/6 (but only one layer / no OPT) ("P2") but only 4 15-color palettes...

plus all the bitmap modes from the previous MSX VDPs.
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Re: S-PPU and the V9990 (also MSX3)

Post by Drag »

It's possible that, if something had indeed been given to Nintendo based on the research that went into the V9990, it might've been some kind of implementation or fabrication detail about the circuit itself (i.e., something that wouldn't be visible to programmers), versus some kind of API or some kind of actual "feature" we could poke at. Therefore, the alleged stolen tech may not be something we'd be able to discern by simply comparing feature sets.
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Re: S-PPU and the V9990 (also MSX3)

Post by Pokun »

Yeah I guess. I hope Nishi or someone will clarify what he meant.
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Re: S-PPU and the V9990 (also MSX3)

Post by Pokun »

It seems he made up with Yamaha again:
Nishi wrote: Dear MSX3 potential users,

I have decided to include V9990 functions into new video for MSX3. It will look like 9958+9990 and 2K support.

Best regards,
Twitter link


He also says that 9998 also still will happen. Medetashi medetashi...
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Re: S-PPU and the V9990 (also MSX3)

Post by ccovell »

Quite frankly, the MSX VDPs (MSX1, MSX2(+) etc) were always relatively primitive for their time; and didn't someone at Yamaha in an interview (online) even admit that the company were beginners at making video hardware, hence being behind the curve?

Knowing this, if anyone's copying off the other, I don't think it would be Nintendo copying from Yamaha. The SNES/SFC's hardware was already demonstrated with large sprites & Mode7 working in late 1988... the same year the MSX2+ was released, so you can picture the technological gap.
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Re: S-PPU and the V9990 (also MSX3)

Post by Pokun »

If Nintendo had already come that far with the S-PPU in 1988 the dates doesn't match very well at all, unless Yamaha were working on the 9978 at the same time as the 9958.
Maybe Mr Nishi's memory is just hazy regarding this.
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Re: S-PPU and the V9990 (also MSX3)

Post by Pokun »

The MSX0 crowdfunding has started. More details here.
It's still not known when the MSX3 is coming though.
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Re: S-PPU and the V9990 (also MSX3)

Post by tvalenca »

Pokun wrote: Sun Feb 20, 2022 9:27 am According to Kazuhiko Nishi, the founder of ASCII Corporation and creator of the MSX computer standard and who is currently working on the MSX3 after all these years (not kidding), the V9990 video chip is the basis for the S-PPU in the Super Famicom. Anyone heard this before? This was news to me anyway if it is true.

After some fans asking him to include the Yamaha V9990 VDP in the MSX3 standard (in a rude fashion) he responded sharply that he won't include it due their history together:
Nishi wrote: Yamaha fail to deliver 9978(later 9990) in time for MSX3. That was the reason name changed to Turbo R. We had only fast CPU. Then Pana used delayed Video chip without our consent saying extra fanctions will be machine depanding non MSX functions.

then by the side, yamaha gave the knowhows of video chip to nintendo and created super famicom without telling us anything. Was that a fair business practices? We dont think so. So we decided not to use 9990 for ever.

we will support uptill 9958 and any future expantion will be strong sprites and 2K and 4K high speed video drawings. All the yamaha patents are expired and now free to use. anyone can copy 9990 but 6 to 12 month work and no resources to do and dont want to delay msx3 launch.
Kazuhiko Nishi on Twitter 2022-01-14


Some quick background: the MSX used the well-known Texas Instrument TMS9918 VDP as its video chip (which were also used by many other systems such as ColecoVision, Sega's console/computer and probably also partly inspired Nintendo's PPU), and ASCII ordered Yamaha to create an upgraded version of it when they updated the standard to MSX2. The result was the Yamaha V9938 MSX-VIDEO, and then they did so again when upgrading to the MSX2+, which was a very small update with the V9958 (basically only adding another scroll axis and a few new modes). Finally they ordered the V9978 from Yamaha for the upcoming MSX3, but Yamaha failed to deliver and they changed the name of the MSX3 to MSX Turbo R (as Nishi said above) due to this, since they only had a new faster CPU (R800) and more RAM for this new MSX standard, not a new VDP as promised. Yamaha finalized the new VDP but it was rejected, so they stripped it down, removing its backwards-compatibility with the V9958, and renamed it the V9990. They used it in some computer video cards I think, and the Dutch company Sunrise made the GFX9000 MSX cartridge (1994), allowing to use it as an external video card for any MSX, and a few other companies released similar products using the chip. A few MSX "homebrew" games that uses it do exists.

Thoughts about this (or even the MSX3)?
Well... Maybe mr. K Nishi is getting older and can't remember things properly... (and I mean that with no disrespect) But I'm adamant to say that he confused SNES with Genesis.

Let's talk about facts:
- MSX enhanced VDPs (not the TMS ones) were all developed between ASCII Corporation (Nishi's company) and Yamaha, while all Nintendo chips at that time were developed by companies from another zaibatsu, namely Ricoh but sometimes Sharp. (I don't think Nintendo ever used a Yamaha chip on any product)
- Yamaha developed custom chips for both Mark III/Master System and Genesis/Mega Drive; Genesis' VDP Yamaha name designation is YM7101 (which actually contains the Genesis VDP itself, a SMS compatibility video mode, and a SN76489 Texas Instruments PSG -which was already embedded the SEGA 315-5124 chip and its subsequent designs)

And this one isn't a fact but... Genesis VDP's design looks ridiculously similar to the V9990. Same resolutions, same VRAM type (dual-ported DRAM), same 4bpp graphics using one of four 16-color sprites capable of simultaneous 64 out of 32768 colors (which implies not only same color pallete structure but same 15-bit color DAC), same dual plane with hard transparency and priority, same sprite engine that could place any sprite before or after the background, same Line interrupts, blitter, DMA, the works... Of course SNES has some (or most) of these capabilities, but they're mostly different on a technical standpoint. Of course the V9990 being intended as a personal computer VDP it has a number of features that didn't made sense on a gaming console (such as 512k of VRAM, japanese character generator, bitmapped video modes with cursor support, digitization and superimposition support, higher scanrate video modes -non interlaced 600 and 640 line modes)
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Re: S-PPU and the V9990 (also MSX3)

Post by TmEE »

MD VDP doesn't have 15bit output, it looks to have readyness for 12bit format but the lowest bit of each channel never made it in and you have 9 bits instead. It looks like they ran out of silicon to have all the extra CRAM bits (there is space but it is in wrong side of the chip pretty much). There really isn't any real similarity between V9990 and MD VDP either, there are completely different design goals between the two with only common thing being heritage to TMS991x chips through Yamaha.
Last edited by TmEE on Wed Mar 13, 2024 11:55 am, edited 1 time in total.
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Re: S-PPU and the V9990 (also MSX3)

Post by psycopathicteen »

Was the YJK color space a bug? It looks like they tried to implement a hardware YUV color mode but accidentally switched blue with green.
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