SPDif and PCM67 ??

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Hum i have studied the board, and the M6538 might actually be a µC.

I have checked the datasheet for PCM1710 and there it was a good schemo with the CS8412.

I am trying to locate a datasheet for the M6538 ic, but looking at the schem in the pcm1710 datasheet it seems that i might be possible to connect the CS directly to the PCM67.

What do you think ?
An externally hosted image should be here but it was not working when we last tested it.
 
That schematic will not work because SYSCLK will be wrong.
Just so you don't go off track at this late stage the OKI MSM6538-01, to give it it's full name, is a digital filter and digital attenuator. I do not have the datasheet but I do have a fragment of a schematic that uses a variant, MSM6538-01GS-VKR1, with a few more pins all of which are NC.
Presumably you have the the datasheet for the PCM67. In it You will see it has a serial input mode, so in theory, one could connect it directly to the receiver but you will also see the PCM67 is designed to work with an oversampling filter. The 1-bit dac requires at certain level of oversampling for optimum performance,
see page 10.
 
MSM6538-01GS-VKR1
 

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Not quite. The '6538 and the '67 are running off a 384Fs master clock. The '8412 only provides 256Fs. You need to have all three devices in the same clock domain. The simplest way to do that is run the '8412 in slave mode but you will need one or two more inexpensive chips for that.
 
I have started to think about giving up the dac project.

I believe that the stuff on the md board is blown, i remember that i drew wires with 5v or more over the md main board which most likely burned out the jacks board as well.

And the cd player i took the board from (the sony all in one) was dead, only the sled motor and laser diode (or the focus lens actuator coil) worked if i remember right so theres a big chance that the dac and the other ic is broken, which makes me think that i should give up the whole idea or just get a ic that takes spdif in and bumps out stereo analog audio direct without extra digital filters or separate dac chips.
 
BUMP!

What would happen if the freqs are wrong between spdif receiver and dac ? like if the dac is for 384Fs and the 8412 outputs 256Fs, no sound, faulty sound or correct sound but interference ?

Cant i mod the dac thing so it also runs off the 8412 256Fs clock ? Should be just simply removing the crystal and input the 8412 master clock instead, or ?
 
Tekko said:

What would happen if the freqs are wrong between spdif receiver and dac ? like if the dac is for 384Fs and the 8412 outputs 256Fs, no sound, faulty sound or correct sound but interference ?

Clicks and pops at the very least.


Cant i mod the dac thing so it also runs off the 8412 256Fs clock ?

No.


Should be just simply removing the crystal and input the 8412 master clock instead, or ?

Only if you design your own silicon.

The answer lies in post #19
http://www.diyaudio.com/forums/showthread.php?s=&threadid=72379&perpage=10&pagenumber=2
 
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