Nintendo/Ikegami's 80s Arcade graphics chip?

[FloResolution]

What is the name of the graphics chip used in early 80's Nintendo Arcade games? The ones developed by Nintendo R&D and Ikegami. Such as the Donkey Kong games, Mario Bros., & Radar Scope.

Is there much data about it? Palettes and stuff like that. The Wikipedia article on Sprites mention the specifications on sprites from the aforementioned games. How does it compare to the NES graphics processor? Could the NES potentially use it?

[TmEE]

There isn't a singular graphics chip there but a whole board of discrete logic and sometimes some simple programmable logic chips, that in their entirety make up the graphics and sound etc. functions. When you look at photos of the actual PCBs of these games you see a zoo of parts.

[Bavi_H]

The Wikipedia article on Sprites mention the specifications on sprites from the aforementioned games. How does it compare to the NES graphics processor?

In the Wikipedia article on sprites, the data table has information for both the Donkey Kong arcarde hardware and for the NES, so you could compare the values in the table for both systems.

From Wikipedia Sprite (computer graphics) - Systems with hardware sprites:

Code: Select all

A: Nintendo Donkey Kong, Radar Scope (arcade)
B: NES/Famicom

                        A           B
Sprite hardware......:  (blank)     Ricoh RP2C0x PPU
Introduced...........:  1979        1983
Sprites on screen....:  128         64
Sprites per scan line:  16          8
Max. texels on line..:  256         64
Texture width........:  16          8
Texture height.......:  16          8, 16
Colors...............:  3           3
Zoom.................:  Integer     No
Rotation.............:  No          Horizontal and vertical mirroring
Collision detection..:  Yes         Partial
Transparency.........:  Color key   Color key

Is there much data about it? Palettes and stuff like that.

For some more information about how the Donkey Kong arcade hardware's palette system works, you can look at the following page: Donkey Kong Hacks dot net - Hacking DIY - Change Text and Sprite Colors

In particular, I noticed the color table on that page:

donkey-kong-color-table.png

can be reorganized into the following pattern:

donkey-kong-color-table-rearranged.png

Or, equivalently, the individual bits have the following purpose:

Code: Select all

byte in c-2j.bpr      byte in c-2k.bpr
0 0 0 0 R4 R2 R1 G4   0 0 0 0 G2 G1 B2 B1

R4 R2 R1 = 000 for max red   to 111 for no red
G4 G2 G1 = 000 for max green to 111 for no green
   B2 B1 =  00 for max blue  to  11 for no blue

[segaloco]

Purely anecdotal evidence as I don't remember where I read this to even go looking for it currently but allegedly the Donkey Kong discrete logic is in turn based on Namco hardware designs like Galaga. My understanding of the lineage to the PPU then is that Nintendo provided the Donkey Kong boards to Ricoh with the intent of creating an IC generalizing the discrete logic of the board.

There was some sort of snafu between Nintendo and Ikegami leading to Nintendo not being able to use their design specs directly, or something like that, hence bringing Ricoh into the picture to suss out the necessary details from the existing arcade hardware. What I'm wholly unaware of is whether it took any actual decapping of the bits on the board or if the discrete logic was loosely-integrated enough that the specific chips could be trivially modeled and all of the integration work was just miniaturizing the whole circuit.

If anyone has any concrete sources confirming (or contradicting) this history, I'd love to see them. I'm quite interested in tracing the "DNA" of hardware in this way, a design rarely crops up in a vacuum. The direct ancestry of any given design stands to shed light on why certain decisions were made, what potential could've arisen in a design, and makes analysis of features easier because if you can explain 60% of something in terms of a prior art. Then you only need to figure out the 40% of it that's new in isolation, the rest of the analysis can draw from said prior art as well.

[tepples]

The other chromosome was probably Texas Instruments' TMS9918 VDP. Reportedly, someone at Nintendo was impressed by Coleco's competent port of Donkey Kong to the ColecoVision. See 6502freak's topic.

[segaloco]

Not surprising honestly, the TMS9918 seems to have had quite the long shadow. I'm forever kicking myself for losing my TMS9918 manual, I actually had one of the original yellow Ti publications on the thing, it's a painful gap in my current library. I've got a Ti-99/4A now too with the assembler/editor and accompanying manual...oh what I wouldn't give to find another copy of that.

This always makes me wonder how successful the Ti-99/4A could've been if they just ran it on a stock chip like the 6502 or Z80. The poor thing suffered since it was both on their weird little TMS9900 CPU *and* the fact that most stuff didn't run "natively", rather, there was some sort of interpreter situation going on up under almost everything. It's called "Graphic Programming Language", it was similar to the idea (but not implementation) of what Thumb is to Arm, a compacted ISA, but was done very inefficiently (yeah yeah citation needed...that assessment is from opinion articles). Only via the assembler/editor could you squeeze raw individual operations out of the CPU. Ti was on the cusp of computing greatness and they missed it by just a bit. Luckily their little IC didn't die in obscurity with the 99/4A and went on to inspire a number of console designs.

[Gilbert]

It's interesting that the TMS9918 was used in so many (nearly identical internally) systems that it had a number of successors developed, not by TI itself but by other parties, such as the VDP for Sega Mark III/SMS (and the Mega Drive by extension) and the MSX2 VDP, however large or small the enhancement might be.

Have Nintendo not ditched backwards compatibility early (probably for the better) during the development of the Super Famicom, we could also have an enhanced successor of the Famicom PPU (whose opportunity was passed to the VTxx clone chips).

BTW, haven't looked at specs, but since Donkey Kong is a single screen game (don't know about Radar Scope), are there any scrolling functionality on that arcade board? If not, then it's a great decision they made that they didn't copy the features verbatim of this arcade game (or, could not do this legally) when designing the Famicom.

IMO, from that point on, the three defining features that gave consoles an edge over computers at that time were i) hardware scrolling, ii) hardware sprites and iii) "better than beeper" audio (aside from being in general cheaper than a computer and could be hooked up to a regular TV set directly). The Famicom ticked all three, and this paved the way to have even better games in the latter part of its life; otherwise it would be limited to single screen games like DK and Mario Bros. TM9918 based consoles/computers didn't have all three yet as they lacked hardware scrolling and the single colour sprites were not that appealing.

[Guest34546]

Have Nintendo not ditched backwards compatibility early (probably for the better) during the development of the Super Famicom, we could also have an enhanced successor of the Famicom PPU (whose opportunity was passed to the VTxx clone chips).

It's kinda half-way there since a lot of functionality matches the Famicom, and mode 0 has a lot of strange attributes that don't fit as a default mode but do fit for a Famicom backwards compatibility mode.

[creaothceann]

TMS9918 manual

This one?

[FloResolution]

Damn! I tried to reply and ended up editing my post instead, how do I fix it?

[Fiskbit]

PhpBB doesn't store previous versions of posts, so they can't be recovered after edits or deletion, but I was able to easily recover the content from a search engine cache and edit it back in for you.

[FloResolution]

PhpBB doesn't store previous versions of posts, so they can't be recovered after edits or deletion, but I was able to easily recover the content from a search engine cache and edit it back in for you.

Thanks bruv. Honestly, I should've thought of looking at cached versions.

Anyway, my reply question: Are the Radar Scope/Donkey Kong graphics the same/similar to the graphics on the Arcade Punch Out?

[FloResolution]

For some more information about how the Donkey Kong arcade hardware's palette system works, you can look at the following page: Donkey Kong Hacks dot net - Hacking DIY - Change Text and Sprite Colors

In particular, I noticed the color table on that page:
donkey-kong-color-table.png
can be reorganized into the following pattern:
donkey-kong-color-table-rearranged.png

So it uses 256 colors. Does that mean it's kinda similar to the "RGB NES" palette in the fact that it has an 8 bit palette?

[Pokun]

Radar Scope didn't use scrolling IIRC, it's a Space Invaders / Galaxian type of shooting game, just with a perspective view.
It has unused sound capabilities where Pauline shouts "Help!" but Miyamoto thought it sounded like something else and removed it.

Punch Out looks a lot more advanced and does feature scrolling.

According to the Mame history file, there is a rare Radar Scope conversion version that features slightly different gameplay.

[Drag]

It's interesting that the TMS9918 was used in so many (nearly identical internally) systems that it had a number of successors developed

I think this is due to it being a freely-available, affordable off-the-shelf part, kinda like how the AY-3-8910 and SN76489 are super common and have seen their fair share of derivatives.

Fun fact, Commodore was trying to shop both their VIC chips around and just nobody was biting at that time, and then they decided to build their own products which used them. Both were designed specifically with video games in mind, rather than as computer displays.


Speaking of discrete video and audio in arcade games, it's really interesting to see how many times Galaxian hardware was reused and expanded on. I don't know if any Galaxian DNA would've made it into Radar Scope or Donkey Kong PCBs, but it wouldn't surprise me if it did.