Nintendo DS processor: does it contain a GPU?

[Simon82]

Hello to all,

somewhere I've read that Nintendo DS ARM9 66Mhz processor contain a real Graphic unit used for triangle setup of something like this, obviously without any post processing filtering like bilinear.
I've also read that it contains a sort of T&L engine.
What do you think?

Bye

 

[Fafalada]

A couple of CPU cores, a couple of graphic cores, a lot of separately addressable memory banks (double digits), lots of buses.

Think portable Saturn

 

[Simon82]

A couple of CPU cores, a couple of graphic cores, a lot of separately addressable memory banks (double digits), lots of buses.

Think portable Saturn

Mhh... but ARM7 33Mhz cpu on the DS has got a graphic cores itself? It's used for other things as retrocompatibility or second screen but ...

 

[Squeak]

A couple of CPU cores, a couple of graphic cores, a lot of separately addressable memory banks (double digits), lots of buses.

Think portable Saturn

Only more inviting to develop for, I hope?
About the texture compression, we know it's VQ, but not regular palette based. Can you tell us more?

 

[diddlyD]

its got two 2d engines, one for each screen. these are very similar to the GBA 2d engine, except beefed up a good bit.

tied to the first 2d engine is a 3d engine that supports basic hardware transformation and up to four directional lights. it also supports a quick and dirty specular lighting method, non filtered single texturing, shadow volumes, environment mapping, and full screen anti aliasing.

the arm9 processor is tied to these graphics units and manages them as well as general game logic. the arm7 is generally hands off to the developer, used through library calls for sound, networking, and other tasks (similar to the second mips cpu in the psp), as well as backwards compatability for GBA games.

 

[sfried]

Think portable Saturn

Oh please...If this is a good reason to bring Silhouette Mirage to the DS, I'll take it!

the arm9 processor is tied to these graphics units and manages them as well as general game logic. the arm7 is generally hands off to the developer, used through library calls for sound, networking, and other tasks (similar to the second mips cpu in the psp), as well as backwards compatability for GBA games.

I hear DS sound can take up to 16-channels. But can it rival SNES' SPC audio chip?

 

[SedentaryJourney]

While we're asking questions about the DS, anyone know what version of 802.11 it uses?

 

[DeadlyNinja]

I hear DS sound can take up to 16-channels. But can it rival SNES' SPC audio chip?

The SNES has only 8 channels of sound, so it's definitely more powerful than the SNES.

 

[Rainbow Man]

The SNES has only 8 channels of sound, so it's definitely more powerful than the SNES.

The Mega Segadrive had more sound channels also than SNES. But its sound channels were mostly FM beep and boop style sounds and thus dd not sound nearly as good. So just going by nmber of channels tells very little.

SNES sound channels were of exquisite quality for its time. I wonder if DS can really rival that especially with SNES' DSP effects.

Peace.

 

[Fafalada]

Only more inviting to develop for, I hope?

Haven't experienced Saturn personally, on paper they are both very similar oldschool design philosophy though.
DS is a strange mishmash of modern features and just plain whacky stuff (the rasterizer in particular). With handheld software far less focused on tech(especially when there's no tech competition with other platforms), it kinda wins by default as more inviting.

About the texture compression, we know it's VQ, but not regular palette based. Can you tell us more?

Basically it's S3TC with detached color tables. Each texel block carries extra overhead - a pointer(16bit) to address it's associated CLUT, which allows CLUT data to be shared between blocks as well as across any number of textures (including regular paletted ones).
Also offers the choice between 2+2 and 4 distinct colors in each block, which helps with textures where S3TC sucks the worst (sharp color transitions, hand drawn art...).

You can calculate what that means for compression ratios as homework

 

[Rainbow Man]

You seem to know a lot about the DS!

Can you tell if the video memory of the DS is on the same chip as the GPU/CPUs or if it sits in the 4 (?) MB of main RAM?

Peace.

 

[roninja]

a shame they did not go for an MBX'd version....

 

[Rolf N]

Basically it's S3TC with detached color tables. Each texel block carries extra overhead - a pointer(16bit) to address it's associated CLUT, which allows CLUT data to be shared between blocks as well as across any number of textures (including regular paletted ones).
Also offers the choice between 2+2 and 4 distinct colors in each block, which helps with textures where S3TC sucks the worst (sharp color transitions, hand drawn art...).

You can calculate what that means for compression ratios as homework

Without the number of texels per block the excercise is incomplete

Can you tell if the video memory of the DS is on the same chip as the GPU/CPUs or if it sits in the 4 (?) MB of main RAM?

Peace.

Extra. Everything's extra.

 

[Rainbow Man]

Extra. Everything's extra.

Wih this I guess you mean it's 4MB + extra video memory (presumably on the CPU chip)?

I believe I read somewhere the DS had around 700kb of video memory. That seems quite a lot for a handheld does it not? I guess it's DRAM and not SRAM..

I would love to see what some demoscene guys could do with all of it. I remember from my old Amiga days.. That thing had half a megabyte of memory and I guess around a quarter of it if not more went to the music and they coul dstill do some amazing things with it.

I had to carry that thing for a mile from the stoer the day I bought it (this was 1987 and the box was big and heavy) and some kid asked me how much memory it had. When I answered his eyes bugged out. He was used to the commodore C64!

In all a perhaps messy piece of kit but a competent one none the less it would seem. It's very attractively packaged that's for sure.

Peace.

 

[Fafalada]

Without the number of texels per block the excercise is incomplete

I admit I haven't spelled it out - but reading between the lines, you can figure it out

 

[Rolf N]

Wih this I guess you mean it's 4MB + extra video memory (presumably on the CPU chip)?

Yes. I think all logic and memory in the DS are integrated on a single chip (except for the speaker amp and other such "brutal" stuff). But the video memory (and a few more memory banks) do not count against the 4MB. They are separate pools of memory.

I'm trying to find a nice image of a disassembled DS but no luck so far.

I believe I read somewhere the DS had around 700kb of video memory. That seems quite a lot for a handheld does it not? I guess it's DRAM and not SRAM..

I really can't say anything about the vram size.
The 4MB chunk of memory is slower than the other, smaller memory pools though, and I have no trouble assuming it's eDRAM, to minimize area, versus SRAM for the other, smaller and faster memory banks.