6502 Processor as a DAC?

[The Black Adder]

Hi there.

Being from a BBC micro background I was wondering if the 6502 processor would be able to be utilised as a DAC?

It's an 8 bit CPU with a 16 bit address bus. Possible? or crazy talk..

A strange one to ask but it was just a thought...

Cheers
Joe

[StanleyB]

It was used in the BBC Micro and Commodore C64 as such. However it's an 8 bit processor of limited speed. You'll need to go up to the 68000 or higher I reckon before you would get anything sensible sound wise.

[The Black Adder]

hmm... 68000 ey. Good ol Amiga stuff. Thats interesting though. I wonder if and how difficult it would be to make?

[lurcher]

You are better looking at FPGA's to get the sort of io that is needed.

[mervinb]

The microprocessors found in PCs do not have analogue outputs, which are the very important 'A' in D-A-C, so even the fastest x86 / 64-bit chips can't be forced to generate the audio which you're looking for.

On the face of it, dacs are pretty basic devices, taking a series of 16- or 24-bit digital bits, fed at somewhere between 44.1 and 192kHz per sample, but the conversion and digital filtering that occurs internally is pretty hairy. I think early generation microprocessors will sweat very hard to cope with the signal processing tasks that take place in dacs.

[The Black Adder]

I wonder if using a multiple of CPU's in parallel would or could do the business? I think it would be interesting to see if something like the 6502 could do the business of a modern DAC unit.. if pressed.

[lurcher]

The microprocessors found in PCs do not have analogue outputs, which are the very important 'A' in D-A-C, so even the fastest x86 / 64-bit chips can't be forced to generate the audio which you're looking for.

Well, it can be done with a single digital output with a low pass filter, if you output DSD then a low pass filter will reconstrict the audio. But again, I think you need the speed of logic not a processor hence the FPGA