XMOS-based Asynchronous USB to I2S interface - Page 182 - diyAudio
Go Back   Home > Forums > Source & Line > Digital Source

Digital Source Digital Players and Recorders: CD , SACD , Tape, Memory Card, etc.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 25th June 2013, 10:16 AM   #1811
JensH is offline JensH  Denmark
diyAudio Member
 
Join Date: Jul 2009
Unfortunately the phase relationships between the master clock and the other clocks are not specified in the data sheet. But since it is claimed that it works, even with a master clock, which is not synchronized at all with the other clocks, I would also assume that the phase of a synchronized clock is not critical. There should be plenty of possibilities to reclock the slower signals internally to also avoid the risk of metastability.

For other DAC's it is clearly specified. Here are a couple of examples:

CS4398:
MCLK can be at any phase in regards to LRCK and SCLK. SCLK, LRCK and SDATA must meet the phase and timing relationships outlined in Section 2.

PCM1794A:
The PCM1794A requires the synchronization of LRCK and the system clock, but does not need a specific phase relation between LRCK and the system clock.
  Reply With Quote
Old 25th June 2013, 12:35 PM   #1812
diyAudio Member
 
Join Date: Oct 2008
Location: Bologna, Italy
Default Arduino lcd for WaveIO

I implemented the lcd display idea of Doede posted in this thread some days ago (and fully described on his website DDDAC site) based on Arduino Uno and 16*2 lcd.

It's easy to build, affordable and customizable. You can show any message you want, provided a very basic knowledge of programming code.
I was comfortable with leds, but this is really fine.
If anyone is interested in building it and need some help or advice, feel free to ask.

Thank to Doede for the input.
Attached Images
File Type: jpg LCD_WaveIO_Arduino.jpg (7.8 KB, 857 views)
  Reply With Quote
Old 25th June 2013, 12:53 PM   #1813
diyAudio Member
 
Join Date: Jul 2010
Default qusp...

Quote:
Originally Posted by qusp View Post
actually barrows, all info i've seen oft' repeated and from my own experience, its the opposite, inverted Mclk. thats why this was provided as the default on the fifo Si570 board (though you can choose)
Thanks for that info. You can confirm that the masterclcok needs to be exactly 180 degrees to bit clock for synchronous clocking of the ESS 9018?
I know the ESS DAC will work with masterclock not synched to bit clock, but my understanding is that doing this will allow the ASRC and DPLL to become active-the entire reason I, and others, want to synchronously clock the ESS is that we want to make the ASRC and DPLL idle, because we do not want the DAC to re-sample the data asynchronously. Using an out of sync MC would defeat the purpose of synchronous clocking as I understand it-If one is OK with the ESS' onboard ASRC being active, then one can just go ahead and provide an independent 80 MHz-100 MHz masterclock for all sample rates and be done with it, but my experience is that synchronous clocking sounds better given a low jitter source.

Is Dustin (ESS designer team member) still active here? Lucien, you could try sending Dustin an inquiry via PM here.
  Reply With Quote
Old 2nd July 2013, 02:22 PM   #1814
diyAudio Member
 
Join Date: Jul 2010
I am currently building an active crossover setup with the miniDSP mini sharc and need to fix the sample rate to the 48Khz i2s input of that board. Is there a way of forcing the waveio to output a fixed sample rate or is it always going to pass the sample rate of the file it is given?

Thanks
  Reply With Quote
Old 2nd July 2013, 02:43 PM   #1815
diyAudio Member
 
Join Date: Jul 2010
Default Lucien, update

I have heard from two reliable sources now, that for synchronous clocking of the ESS 9018, the master clock and bit clock need to be synchronous, but that inverted phase as mentioned above is not necessary. I consider these sources trustworthy (one is a manufacturer who makes ESS based DACs, and produces their own USB interface). Apparently Dustin from ESS has mentioned that there may be a performance advantage to having the rising edge of the master clock signal aligned with the falling edge of the bit clock signal; but no one appears to have observed any actual advantage from doing so.
  Reply With Quote
Old 4th July 2013, 11:32 AM   #1816
diyAudio Member
 
Join Date: Nov 2007
Quote:
Originally Posted by orangeart View Post
I am currently building an active crossover setup with the miniDSP mini sharc and need to fix the sample rate to the 48Khz i2s input of that board. Is there a way of forcing the waveio to output a fixed sample rate or is it always going to pass the sample rate of the file it is given?
Thanks
Well, there was a case when I had to change the base firmware and allow the card to work with 44.1 & 48 Khz sample rates. At that time I forced the WaveIO to report maximum sample rate to be 48 Khz @ USB enumeration. Any higher fs tracks than 48 will force the player to report an error/warning. I guess I could do that for you too.. free of charge, of course

@ barrows: Thank you and thank you! I didn't managed to talk with Dustin but I guess things are quite settled for now... I'll see what path do I have at disposal to implement all the MC/I2S clock requirements.
Thank you again,
Lucian
__________________
Contact link for WaveIO USB-to-I2S/SPDIF board.
Daughter card GB list for WaveIO can be found here

Last edited by Lorien; 4th July 2013 at 11:34 AM.
  Reply With Quote
Old 4th July 2013, 04:31 PM   #1817
diyAudio Member
 
Join Date: Jul 2010
Quote:
Originally Posted by Lorien View Post
Well, there was a case when I had to change the base firmware and allow the card to work with 44.1 & 48 Khz sample rates. At that time I forced the WaveIO to report maximum sample rate to be 48 Khz @ USB enumeration. Any higher fs tracks than 48 will force the player to report an error/warning.
Hi Lucian, That could work but the sample rate need to be fixed rather than allowing anything bellow (x)Hz through.

I guess there is no way of Implementing ASRC code with the waveio. I ask as there does seem to be some XMOS implementations out there specifically working as an ASRC.

Cheers

Stefan
  Reply With Quote
Old 5th July 2013, 08:18 AM   #1818
diyAudio Member
 
soundcheck's Avatar
 
Join Date: Mar 2005
Location: D
Hi there.

Has anybody replaced an SPDIF coax output with Toslink on the WaveIO??

Cheers
  Reply With Quote
Old 5th July 2013, 08:34 AM   #1819
diyAudio Member
 
soundcheck's Avatar
 
Join Date: Mar 2005
Location: D
Lorien.

I know you're busy with squeezing the last 0,2% of quality out of your product.

I'm wondering if you finally considered to go multichannel I2S or SPDIF?


Multichannel SPDIF in particular. There is no such interface in the market.

The USB Streamer from MiniDSP comes with 8 channel I2S. But that would require an I2S to SPDIF interface to be build. And I'm wondering how that USB streamer would compare in quality to your interface.

Many people could replace stuff like Behringers, MiniDsp Nano Digi asf. and use existing DACs, full digital amps etc. and use the PC as DSP which much higher flexibility and performance then MiniDSP products.

Subwoofer integration could easily accomplished. Multichannel and speaker activation would be much easier.

Cheers
  Reply With Quote
Old 5th July 2013, 08:37 AM   #1820
diyAudio Member
 
Join Date: Jul 2010
Soundcheck, if you were to got this route, what software would you be using to do the realtime crossover / dsp ?

Stefan
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
exaU2I - Multi-Channel Asynchronous USB to I2S Interface exa065 exaDevices 1357 3rd March 2014 08:51 PM
Introducing miniStreamer: Native 24/96 USB to I2S / SPDIF interface minidsp miniDSP 39 5th January 2014 11:00 PM
Ultimate USB to I2S interface sampler Digital Source 206 30th January 2012 03:45 PM
Is it possible to develop a ASIO driver for PCM2900 based USB Audio interface? cxhawk Digital Source 7 3rd December 2010 02:30 PM
interface I2S with USB mermoz Digital Source 0 21st February 2003 10:34 AM


New To Site? Need Help?

All times are GMT. The time now is 08:13 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright ©1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2