Tír Na HiFi

tony wrote:See MQn and Buildanaudiopc Aleg, I have the patience but it is technically on another level to anything done previously.
Looking forward to the results. A brief look on some other forums suggest this is being pursued on a fairly broad basis on diy sections. I wonder will bringing it to the zuma pc level be the biggest challenge but time will tell?

I will have to use my sons skills and interest in linux to get some handle on this stuff.

Tony

I hope/expect there may be not much need of Unix expertise as there are special builds that have been optimised for audio playback and already contain all software required for playback and are capable of accessing the I2S signal lines.

So maybe it won't be that 'bad'.

Chees

aleg

No raspberry clock talk tonight?
Was thinking about the master clock thing working synchronised or async
Synchronised might seem like a good option as the signal path is so short
And less meaning more thing been in fashion right now
Maybe We should start out with short and simple first
Then make it complicated later

Anyway eager to get started
Hope it doesn't suck

Got a working DAC attached to RPi I2S output
Logged into Volumio on RPi (root/volumio) as terminal & followed the update commands:

This takes about an hour from start to finish.

Edited /etc/modules file as follows (I downloaded & used nano editor, built-in VI editor is pants) Enabled I2Son setting in System option of Volumio menu & rebooted RPi

When I select a file from my USB stick to play, I get no sound & progress dial doesn't move.

When I select Playback option from Volumio menu, the "Audio Output" field says "Nothing selected" & no audio devices are available form the drop down list. IChanging the last line of the Modules file to "snd_soc_hifiberry_dac" or to "snd_soc_pcm5102a_dac" makes no difference - see this post http://volumio.org/forum/hifiberry-modules-t634.html (the Hifiberry is the same DAC chip, pcm5102a, as I'm using)

Mark, do you see your Buffalo DAC as a selection in this drop-down list?

Linux command "aplay -l" doesn't list any souncards

nige2000 wrote:No raspberry clock talk tonight?
Was thinking about the master clock thing working synchronised or async
Synchronised might seem like a good option as the signal path is so short
And less meaning more thing been in fashion right now
Maybe We should start out with short and simple first
Then make it complicated later

Anyway eager to get started
Hope it doesn't suck

Nah, clock issue is already solved :hide:

On the BBB there is a master clock signal available that could be used for clockless DAC-boards to work in a synchronised way.

The DIYINHK board can have a local oscillator mounted to act as a clock for the DAC chip in an asynchronised way and you could also use an external masterclock card for that purpose.

I also read in the BBB SRM that the clock pins on the processor are both input and output, and that would open up the option to use a separate masterclock board to synchronise both the BBB and the DAC from the same external source, so with a better clock and/ or a different oscillator frequency than is mounted on the BBB itself. The oscillator on the BBB can be switched off from software.

So plenty of options to try out.
BTW. I ordered two DAC boards from DIYINHK, where one is modified to carry an onboard oscillator and the other is unmodified.

They shipped this morning, so now sit and wait when they will be delivered. Which gives me time to think about the PSU for the boards.

Cheers

Aleg

Aleg wrote: Nah, clock issue is already solved :hide:

On the BBB there is a master clock signal available that could be used for clockless DAC-boards to work in a synchronised way.

The DIYINHK board can have a local oscillator mounted to act as a clock for the DAC chip in an asynchronised way and you could also use an external masterclock card for that purpose.

I also read in the BBB SRM that the clock pins on the processor are both input and output, and that would open up the option to use a separate masterclock board to synchronise both the BBB and the DAC from the same external source, so with a better clock and/ or a different oscillator frequency than is mounted on the BBB itself. The oscillator on the BBB can be switched off from software.

So plenty of options to try out.
BTW. I ordered two DAC boards from DIYINHK, where one is modified to carry an onboard oscillator and the other is unmodified.

They shipped this morning, so now sit and wait when they will be delivered. Which gives me time to think about the PSU for the boards.

Cheers

Aleg

i can see an array of i2s configurations appearing
when do you expect the BBB
think diyinhk delivery takes about 2 weeks
they also have 3.3v/5v low noise regulators in stock too
ive got one here somewhere ill try that at some stage

jkeny wrote:Got a working DAC attached to RPi I2S output
Logged into Volumio on RPi (root/volumio) as terminal & followed the update commands:

Code: Select all

sudo apt-get update 
sudo apt-get install git-core
sudo apt-get install binutils - there was an error in original post on volumio forum
sudo rpi-update
sudo reboot

This takes about an hour from start to finish.

Edited /etc/modules file as follows (I downloaded & used nano editor, built-in VI editor is pants)

Code: Select all

snd_soc_bcm2708
snd_soc_bcm2708_i2s
bcm2708_dmaengine
snd-soc-pcm5102a
snd_soc_pcm5102a_dac

Enabled I2Son setting in System option of Volumio menu & rebooted RPi

When I select a file from my USB stick to play, I get no sound & progress dial doesn't move.



When I select Playback option from Volumio menu, the "Audio Output" field says "Nothing selected" & no audio devices are available form the drop down list. IChanging the last line of the Modules file to "snd_soc_hifiberry_dac" or to "snd_soc_pcm5102a_dac" makes no difference - see this post http://volumio.org/forum/hifiberry-modules-t634.html (the Hifiberry is the same DAC chip, pcm5102a, as I'm using)

Mark, do you see your Buffalo DAC as a selection in this drop-down list?

Linux command "aplay -l" doesn't list any souncards

Hi John

Have you modded the /etc/modules file as follows:


snd_soc_bcm2708
snd_soc_bcm2708_i2s
bcm2708_dmaengine
snd-soc-pcm1794a
snd_soc_rpi_dac

I had the same frustrating result as you until I made the above change. Add this, reboot and do the I2S selection step again, then check with aplay -l on the terminal. You should see a card listed :

-root@volumio:~# aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: sndrpirpidac [snd_rpi_rpi_dac], device 0: HifiBerry Mini HiFi pcm1794a-hifi-0 []
Subdevices: 1/1
Subdevice #0: subdevice #0

The RPi knows nothing of the Buffalo or any other dac, I2S is not a bidirectional interface so there is no way it will know what dac you have hanging off the interface.

Hope that helps a little.

Mark

nige2000 wrote:No raspberry clock talk tonight?
Was thinking about the master clock thing working synchronised or async
Synchronised might seem like a good option as the signal path is so short
And less meaning more thing been in fashion right now
Maybe We should start out with short and simple first
Then make it complicated later

Anyway eager to get started
Hope it doesn't suck

Short and simple - that's me :0)

Lol

So am I right in thinking that the o's can't decipher between dac chips and doesn't even know what a pcm5102a or any other chip is except for the pcm1794a
Why did they not just use i2s in the code instead of a specific chip
Would be more self explanatory
I would have entered my dac chip too

I assumed that the etc/modules referenced a driver in that last line & I already tried the modules coding given on the Volumio forum: But this also got me no sound
I'll try the Russ White settings but like Nige, I don't understand why there are different drivers for I2S DAc chips - they all just use the 3 I2S lines as input & there's no other material difference as far as the RPi is concerned.

I'll try your settings but see that you have snd-soc-pcm1794 instead of snd_soc_pcm1794 (i.e underscores)
Is that a typo?

jkeny wrote:I assumed that the etc/modules referenced a driver in that last line & I already tried the modules coding given on the Volumio forum:

Code: Select all

snd_soc_bcm2708
snd_soc_bcm2708_i2s
bcm2708_dmaengine
snd_soc_pcm5102a
snd_soc_hifiberry_dac

But this also got me no sound
I'll try the Russ White settings but like Nige, I don't understand why there are different drivers for I2S DAc chips - they all just use the 3 I2S lines as input & there's no other material difference as far as the RPi is concerned.

I'll try your settings but see that you have snd-soc-pcm1794 instead of snd_soc_pcm1794 (i.e underscores)
Is that a typo?

John

Those are pulled directly from Russ Whites first post.

In terms of why this stuff makes a difference I would guess these refer to resource libraries in the Linux repositories. You'd need to get an answer from the Volumio/Raspbian gurus, I think. Maybe the "-" vs "_" is a Putty presentation thing...

Mark