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Hardware > GBA Sound Hardware

#130182 - Karlos - Thu May 31, 2007 5:13 pm

Hey there! I was searching the web (and this forum) for quite a long time now. My question is: How does the GBA generate Sound?
Does the GBA have a dedicated Sound CPU or does the ARM7 CPU handle the sound? The same goes for graphics.
Does the ARM7 handle all the sound, graphics and cpu processes? Or does the ARM7 just "serves" as a general Cpu?

I'm sorry if I'm boring you but I just want to have these questions answered.
Thanks in advance :)

Last edited by Karlos on Thu May 31, 2007 8:17 pm; edited 1 time in total

#130188 - Dwedit - Thu May 31, 2007 7:21 pm

The GBA generates sound in software. Using DMA, the sound is sent to the sound hardware's buffer. Sound hardware has a tiny FIFO buffer, 32 bytes large. The frequency of the sound is controlled by a timer, this controls both the frequency in which the sound is sent by DMA, and the rate at which the FIFO buffer is emptied.

Graphics are done by dedicated hardware, except in the bitmap video modes which aren't used much.

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#130196 - Karlos - Thu May 31, 2007 8:16 pm

Thank you :)

I'm sorry, if these questions sound simple to you. But I am not a programmer. I am just very interested in the GBA's hardware in detail.
And I have also found the GBATEK site already, but it is just too much for me to seek an answer for such a simple question in such a (for me) complicated site :)

So you say the graphics are handled by a dedicated chip? So where is it placed then on the GBA's PCB? I can only recognize the ARM7 and the Z80 chips. Then a few smaler ones, especially on the back side. What are these ones for?
Maybe someone could post a link where the PCB layout of the GBA is explained. I would really appreciate that :)

#130241 - tepples - Fri Jun 01, 2007 12:33 pm

Karlos wrote:
So you say the graphics are handled by a dedicated chip? So where is it placed then on the GBA's PCB? I can only recognize the ARM7 and the Z80 chips.

The PPU is on the same die as the ARM7 CPU.
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