Asynchronous I2S FIFO project, an ultimate weapon to fight the jitter

Hey mate,

Check Ian's post here.
You only need the parts listed under the "Standard Configuration" headline (on the 3rd pic).
It's just 7 components if you exclude the headers.

Thakns TheShaman, but I might be a little mistake on the BOM. R10 should be 0 ohm for the standard configuration :).

Ian, it Looks beautiful.
I couldn't keep up with your update, I think that is a good sign for lazy people like me to keep reading.

I received your power management board, I just want to confirm the resistors to make sure I didn't do a silly mistake:
1. R1, 2, 5, 6, 8, 10 are 0ohm
2. R11 is 100ohm
3. R3, 4, 7, 9 are 1kohm
4. R12, 13 are short because my -ve is Gnd

Thanks.



coolhead, for standard configuration,

1. R1, 8, 10 are 0ohm
2. F2 fuse or just short
3. R9 is 1kohm
4. D3 LED
5. D4 4148 or any diode for coil flayback

please refer to the below picture, just add with R10 (0 ohm)

http://www.diyaudio.com/forums/digi...mate-weapon-fight-jitter-139.html#post3223337


Ian
 
Ian I've had a read of the si8605 datasheet, but just want to tripple check, the si8605 could also be used to isolate a GPIO from a microcontroller using on of the unidirectional channels right? I haven't got a i2c control interface on my dac, but I do have a pin that can be pulled low to mute the dac. I am thinking that I could use Si8605 for Si570 serial and this mute pin control.
 
Fifo compatibility with CS8416 and PCM1794A, 24bits, DA Converter

Hi! The second lot of the second group buy is almost closed and I would like to know if placing the fifo between a CS8416 and two PCM 1794A in dual mono configuration could be a problem? Ian? The PCM1794A use a standard 3 wires left jutified I2S protocole... Thanks Fred
 
Si570 interest list: 1. bigpandahk 2. tagheuer 3. hochopeper 4. qusp (of course) 5. AR2 - definitely! 6. wktk_smile 7. hirez69 8. CeeVee - you bet! 9. number9 10. analog_sa - GB maniac 11. edbk 12. atom6422 13. misterrogers - Of Course! 14. NicMac - as usual! 15. Zoran 16. PET-240 17. Coolhead 18. Slartibartfasst 19. SYklab 20. Regland 21. Neb001 22. SPWONG 23. Greg Stewart (also of course!) 24. Vitalica 25. spm 26. Fridrik
 
do you think we could have more of a list? what happened to the formatting? you posting from a phone or something fridrik?

fridrik, why would you use the CS8416? sure it'll work, but at the low price of the spdif module I would just recommend getting that, as a system it all works well. afaik with the latest firmware the fifo allows i2s, PCM, Left justified

I dont know the PCM1794 all that well, it depends on how its dual mono mode works, is it actually sent a discrete left and right channel i2s stream, or does it work like es9018/12 and when set to mono mode the dac is given an address to identify itself as the left or right channel, then both are sent the same stereo stream, but the left channel dac knows to use only the left channel information and vice versa for the right channel dac?

if it needs the i2s to be split into left and right mono streams then no the fifo wont work
 
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Si570 interest list:

1. bigpandahk
2. tagheuer
3. hochopeper
4. qusp (of course)
5. AR2 - definitely!
6. wktk_smile
7. hirez69
8. CeeVee - you bet!
9. number9
10. analog_sa - GB maniac
11. edbk
12. atom6422
13. misterrogers - Of Course!
14. NicMac - as usual!
15. Zoran 16. PET-240
17. Coolhead
18. Slartibartfasst
19. SYklab
20. Regland
21. Neb001
22. SPWONG
23. Greg Stewart (also of course!)
24. Vitalica
25. spm
26. Fridrik
 
Ian I've had a read of the si8605 datasheet, but just want to tripple check, the si8605 could also be used to isolate a GPIO from a microcontroller using on of the unidirectional channels right? I haven't got a i2c control interface on my dac, but I do have a pin that can be pulled low to mute the dac. I am thinking that I could use Si8605 for Si570 serial and this mute pin control.

Yes, correct. Si86056 has both I2C isolator and GPIO isolator. The GPIO is bidirectional. So, it's very easy use for serial communication port (USART, or LVTTL RS232).

Ian
 
do you think we could have more of a list? what happened to the formatting? you posting from a phone or something fridrik?

fridrik, why would you use the CS8416? sure it'll work, but at the low price of the spdif module I would just recommend getting that, as a system it all works well. afaik with the latest firmware the fifo allows i2s, PCM, Left justified

I dont know the PCM1794 all that well, it depends on how its dual mono mode works, is it actually sent a discrete left and right channel i2s stream, or does it work like es9018/12 and when set to mono mode the dac is given an address to identify itself as the left or right channel, then both are sent the same stereo stream, but the left channel dac knows to use only the left channel information and vice versa for the right channel dac?

if it needs the i2s to be split into left and right mono streams then no the fifo wont work

Formating was removed because au noscript in firefox...

Yes your first decription is rigth the I2S signals are connected strait from the CS8416 output to the 2 PCM1794 (left and right ) inputs.

The only two problem I could see are :

1- Is the fifo output able to drive 2 inputs ( probably)
2- The protocol configuration of the PCM1794 : I2S or standard 24 bit right justified
 
hmm, I presume you mean my second description is right, just checked the datasheet and there is no mono mode on the CS8416, I guess with the 1794A you simply set it as the left or right channel identifier either with pull-up/down resistors, or some form of microcontroller.

yes the fifo will drive 2 dacs, particularly with the si570 clock board, which has dedicated clock buffers for 2 dacs
 
DSD question again

I've read through the thread and DSD is not supported. One of the reasons being the need for larger memory. But more and more USB interfaces are becoming capable of passing DSD.

If one looks at the size for DSD64 at 2l.no the size of the DSD file is actually smaller than the size of the PCM file at 24/96K. So I think the only issue is the timing and a way to detect that a DSD file is present. Well, if you use the Amanero board, then there is a DSD signal and this can be leveraged to tell the FIFO that the file is in DSD format.

So the only issue left is timing. I think DSD is just two channels of serial data synchronized to a 2822.4 Mhz clock.

Is this doable?
 
might have to do with the fact that DSD over usb is a container, not an actual native file, then you have the fact in its native form its 1bit... its a completely different way to represent the audio. it would require a complete rewrite of the software. Myself I couldnt really give a toss about it at the moment, last week I went looking to buy some music to bring along to the meet, some DSD, native DSD, the range of available music that isnt just some old file ripped to or converted to DSD is miniscule and is all of a very specific hoity toitier than thou classical genre. I dont buy that converting to DSD at up to DSD512 from a PCM format, then playing it back via a dac that internally processes the DSD as 6 bit audio is a worthwhile way to spend my upgrade money...

once they start releasing more NATIVELY recorded music and not just classical or obscure ethnic folk music, i'll give it another look, for now i'm not convinced we need a dac at all for DSD, just a high performance analogue filter, but i've got better things to worry about.
 
might have to do with the fact that DSD over usb is a container, not an actual native file, then you have the fact in its native form its 1bit... its a completely different way to represent the audio. it would require a complete rewrite of the software. Myself I couldnt really give a toss about it at the moment, last week I went looking to buy some music to bring along to the meet, some DSD, native DSD, the range of available music that isnt just some old file ripped to or converted to DSD is miniscule and is all of a very specific hoity toitier than thou classical genre. I dont buy that converting to DSD at up to DSD512 from a PCM format, then playing it back via a dac that internally processes the DSD as 6 bit audio is a worthwhile way to spend my upgrade money...

once they start releasing more NATIVELY recorded music and not just classical or obscure ethnic folk music, i'll give it another look, for now i'm not convinced we need a dac at all for DSD, just a high performance analogue filter, but i've got better things to worry about.

Agree:).

I've read through the thread and DSD is not supported. One of the reasons being the need for larger memory. But more and more USB interfaces are becoming capable of passing DSD.

If one looks at the size for DSD64 at 2l.no the size of the DSD file is actually smaller than the size of the PCM file at 24/96K. So I think the only issue is the timing and a way to detect that a DSD file is present. Well, if you use the Amanero board, then there is a DSD signal and this can be leveraged to tell the FIFO that the file is in DSD format.

So the only issue left is timing. I think DSD is just two channels of serial data synchronized to a 2822.4 Mhz clock.

Is this doable?

DSD FIFO will be my next project. True, it's 1bit, but would be multi-channels. I will do it with 64Mb memory, should be more than enough.

No any technical problem over there, I just don't have enough time. All verilogHDL code has to be re-written. It plays music stream in totally the different way.

What DSD source you are using now?

Regards,

Ian
 
hmm, I presume you mean my second description is right, just checked the datasheet and there is no mono mode on the CS8416, I guess with the 1794A you simply set it as the left or right channel identifier either with pull-up/down resistors, or some form of microcontroller.

yes the fifo will drive 2 dacs, particularly with the si570 clock board, which has dedicated clock buffers for 2 dacs

Yes nothing particular about the 1794A mono implentation only a few pullup\down resistor to configure the channel(R or L) and the protocol. I don`t get what is the diffrence between I2S and standard 24 bit right justified in the 1794A datasheet. My understanning is that in I2S mode the 1794A will ignore the 8 extra bits precision. The bit clock would than be higher in I2S than in standard mode...
 
Agree:).



DSD FIFO will be my next project. True, it's 1bit, but would be multi-channels. I will do it with 64Mb memory, should be more than enough.

No any technical problem over there, I just don't have enough time. All verilogHDL code has to be re-written. It plays music stream in totally the different way.

What DSD source you are using now?

Regards,

Ian

Hi Ian,

I am using foobar->Amanero USB->Buffalo II DAC. The current fifo board should have enough memory for stereo DSD would it not?
 
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glt, I think probably Ian doesnt want to write new code just for 2 channel, if hes going to do DSD, it'll support the full range of DSD formats including multichannel. otherwise if he did it on the current board, he would end up with people asking about multichannel on the DSD board and it wouldnt be possible without a hardware upgrade.....
 
Si570 interest list:

1. bigpandahk
2. tagheuer
3. hochopeper
4. qusp (of course)
5. AR2 - definitely!
6. wktk_smile
7. hirez69
8. CeeVee - you bet!
9. number9
10. analog_sa - GB maniac
11. edbk
12. atom6422
13. misterrogers - Of Course!
14. NicMac - as usual!
15. Zoran 16. PET-240
17. Coolhead
18. Slartibartfasst
19. SYklab
20. Regland
21. Neb001
22. SPWONG
23. Greg Stewart (also of course!)
24. Vitalica
25. spm
26. Fridrik
27. ccliu