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[Doc Holliday]

Just wondering something..Can the DS use the second CPU as a graphics processor? Or am i completly retarded?

 

[Deleted member 1235]

both of those statements could be true. I'm unsure of the validity of either.

I thought one was the arm7 one was the arm9 or some shit? One does GBA one does DS stuff?

 

[Doc Holliday]

I'm sure each one handles a different screen.

 

[StoOgE]

Im pretty sure one is for GBA compatibility.

 

[nubbe]

It has two separate ARM processors, an ARM9 main CPU and ARM7 coprocessor
You can have them process the same data or work independently. The screens have nothing to do with it…

 

[monkeyrun]

They do work "together" (that's a pretty general btw), but they cannot work in parallel.

 

[maharg]

They do work "together" (that's a pretty general btw), but they cannot work in parallel.

Um, that makes no sense. They can't work together and not in parallel, being seperate chips. What are you trying to say?

 

[monkeyrun]

Um, that makes no sense. They can't work together and not in parallel, being seperate chips. What are you trying to say?

they work together in the sense that they do work together to run a game :lol .
But there's no way they could run in parallel in the sense that one boost performace of the other.

 

[Panajev2001a]

they work together in the sense that they do work together to run a game :lol .
But there's no way they could run in parallel in the sense that one boost performace of the other.

Uhm... of course they cannot boost the performance of a game... they are already working on running the game .

Without the ARM7, the ARM9 would have much more work to do, so the ARM7 is boosting performance by running "in parallel" and working on certain things while the ARM9 is working on others.

 

[monkeyrun]

Without the ARM7, the ARM9 would have much more work to do, so the ARM7 is boosting performance by running "in parallel" and working on certain things while the ARM9 is working on others.

actually that's "in series" *cough*

 

[seismologist]

It wouldn't work like a traditional graphics processor, but essentially yes it can.
You'd need to set up the program to write graphics insructions to the other CPU's memory.

 

[snapty00]

actually that's "in series" *cough*

Looks like some of that ninth-grade electronics terminology finally found a use.

 

[Panajev2001a]

actually that's "in series" *cough*

What I explained is not in series.

Having the ARM9 and the ARM7 work truly "in series" is beyond useless.

That would mean ARM9 does job A_0... completes it and waits... ARM7 does job A_1... completes it... ARM9 does job B_0... etc...

If by in-series you mean like different stages in a GPU (say Clipping, Culling, Vertex Shading, Triangle set-up, Pixel Shading, etc...) then I understand, but they are also working in parallel because I assume they work fully pipelined which means that when the ARM9 has passed work to the ARM7 it can move to do work on something else and does not have to sit idle.

I can understand why they would do this: easier to write a high level library that handles both processors and easier to program hardware as you do not have to worry about synchornization of the two processors.

I would have preferred (I hope Nintendo will allow it if what you say is true) that developers could decide to handle both processors in parallel like you do on PlayStation 2 for maximum performance.

Oh well...

 

[Panajev2001a]

It wouldn't work like a traditional graphics processor, but essentially yes it can.
You'd need to set up the program to write graphics insructions to the other CPU's memory.

Which is how a traditional (VS/PS 3.0) graphics processor does things: for example writing new vertices in a texture from the Pixel Shader and passing it to the Vertex Shader (which cna be run by the CPU too ).

 

[Amir0x]

Panajev2001a is my love.

 

[seismologist]

Which is how a traditional (VS/PS 3.0) graphics processor does things: for example writing new vertices in a texture from the Pixel Shader and passing it to the Vertex Shader (which cna be run by the CPU too ).

It's the same idea from a programming standpoint only you're writing CPU instructions instead of display lists. The API code would need to change but that's about it.

 

[maharg]

Um, what pana beat me to saying. You would never use two seperate CPUs in series. It would be retarded. It just plain doesn't make sense.