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Support for Botic Linux driver

I'm looking to experiment with DSD formats (DFF, DSF and DoP) once I get a cape with DSD switching capability; can 'dsd_native' and 'dsd_usb' both be set to "yes"?

Thanks

Ray
DoP is not a DSD format, just a way to sent DSD samples over a normal PCM audio channel. DoP is not needed when you have a direct connection with your DAC (BBB->DAC via I2S).

The 'dsd_native' and 'dsd_usb' switches are mutually exclusive. If you set both to 'yes', 'dsd_usb' will 'win'.

In case of botic you'll always want to set 'dsd_native' to 'yes' and 'dsd_usb' to 'no'.
If you want DSD to PCM conversion you need to set both switches to 'no'.
 
DoP is not a DSD format, just a way to sent DSD samples over a normal PCM audio channel. DoP is not needed when you have a direct connection with your DAC (BBB->DAC via I2S).

Yes, I know and I don't anticipate using DOP in my BBB/Botic setup, though I believe BBB/Botic caters for DoP data. But I don't think I framed my question very well...

The 'dsd_native' and 'dsd_usb' switches are mutually exclusive. If you set both to 'yes', 'dsd_usb' will 'win'.

In case of botic you'll always want to set 'dsd_native' to 'yes' and 'dsd_usb' to 'no'.
If you want DSD to PCM conversion you need to set both switches to 'no'.

...it just struck me that this isn't a very well thought through configuration setting. It would seem to me more elegant to have a single setting with three mutually exclusive switch settings;

audio_output = "dsd_native" or "dsd_usb" or "pcm"
 
I'm afraid you will need to check signals with oscilloscope.

What about 48kHz and 96kHz sample rates ... do they work?
I've been playing 192/24 files fine for the past couple of days, but today I got 12 tracks though an album, all recorded in 192/24 and halfway through the final track it slowed down as though someone had pulled the power on a turntable and now all 192/24 plays at around 1/4 speed. very weird.
Whilst it's being weird I played the 44/16, 48/16 and 96/24 test tracks you provided in the build and all play totally fine. Only 192/24 has been affected.
A reboot of the bbb didn't fix this.
I wonder if using the 45/49 clocks natively with no hardware divider is very borderline and sometimes just can't sync properly with the bbb
 
Good morning miero.

Just wondering if we could recap on the BBBotic capability with respect to PCM/DSD playback?

Below is a list and I have ticked those I know play successfully (indeed, excellently) on my BBBotic/Acko SO3/Buffalo IIIse setup or, in the case of DSD64, I believe will playback. I'm less clear about the higher rates and would be grateful if you could advise? Maybe something like this list would be a good addition to your botic page?

PCM (16 & 24bit)
44.1KHz ü
48KHz ü
88.2KHz ü
96KHz ü
176.4KHz ü
192KHz ü
354.8KHz ?
384KHz ?
DSD
DSD64 ü
DSD128 ?
DSD256 ?
DOP?
I plan to update my setup to automatically switch between PCM and DSD outputs in the near future and have started to acquire some DSD material.

Also, I'm seeing references to Botic V4, are you able to say anything about what it will bring to the party?

Thanks

Ray
 
I have not tested DSD256 (this is IMHO too much for BBB) and DoP (I do not have such DAC).

Other rates works fine using TPA Hermes-BBB and Cronus prototype boards (using Botic v3 too). I'm using ~50MHz clocks which are decimated by factor 2 before entering BBB.

There are still couple of issues in Botic v4 which prevents publishing it widely. Also no much new exciting features, mostly keeping up-to date with other Linux world and many polishing.
 
Thanks miero, so the list looks like;

PCM (16 & 24bit)
44.1KHz ü
48KHz ü
88.2KHz ü
96KHz ü
176.4KHz ü
192KHz ü
354.8KHz ü
384KHz ü
DSD
DSD64 ü
DSD128 ü
DSD256 ? (requires testing but probably not due to BBB processing capacity)
DOP? (requires testing)

BTW, I'm using 90MHz family clocks on my SO3, divided by 4 for BBB but also clocking the Buffalo IIIse - sounds very good.

Ray