NoSpecialSymbol
Posts: 13
Joined: Sat Dec 12, 2015 6:53 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Fri Jan 22, 2016 6:51 pm

Dear Benjamin,

thank you sincerely for sharing your work!

I must say that your PCB layout looks quite cool. It came out a lot smaller than I expected, despite the additional footprints for future parts!

If you have 1 or 2 spare PCBs and would be willing to mail them across, I'd be happy to share the cost of the PCB order.

I may try and create my own mutations of the board at a later point in time (I'd like to add a 433 MHz transmitter to operate (some remote-controlled power outlets).

Again, thank you very much for the great work.

Christian

BenjaminKe
Posts: 65
Joined: Fri Jan 15, 2016 2:55 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Tue Jan 26, 2016 9:53 am

Thanks :)

I'm still waiting for the PCBs, but I will post here again when I get them.

Of course you can have some (if you need I can also include the optical transmitter (PLT133/T8) or the oscillator - I'm not sure if the one you have fits the layout - the oscillator is a very very small one).

Maybe as a hint:
The pins from the connector which I left free in the middle have a SPI port (I use it to control my Ambilight LEDs).
I think you could also connect a 433MHz transmitter module here ;)

Rene230781
Posts: 11
Joined: Wed Feb 03, 2016 8:01 am

Re: TinyTOSLINK (digital audio output) now for B+, too

Wed Feb 03, 2016 8:10 am

Hey Guys

Great work!

Any news on this? Did you finally finish this?

Best regards
René

BenjaminKe
Posts: 65
Joined: Fri Jan 15, 2016 2:55 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Fri Feb 05, 2016 12:00 pm

Hi,

today I received the PCBs :)

I hope I'll find some time on the weekend to assemble one and test it.

If you need PCB/Parts for a few euro just write me a message or leave a reply here.

Image

Rene230781
Posts: 11
Joined: Wed Feb 03, 2016 8:01 am

Re: TinyTOSLINK (digital audio output) now for B+, too

Fri Feb 05, 2016 12:13 pm

Great! Waiting for your feedback. This will be teseted with RPI 2?

The schematic on Page 6 of this Thread is the final schematic? If ot is it possible to attach the final one? I would like to somehow bring it to a single layer board whic I got flying around here. It will not fit into the RPI Case but I would do some extra case or similar.

***EDIT***

Ok seem to be a modified Schematic as R13 isn't implemented in the old one. :-(

;)

regards
René

BenjaminKe
Posts: 65
Joined: Fri Jan 15, 2016 2:55 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Fri Feb 05, 2016 12:36 pm

Hi Rene,

I only added a few resistors in the datalines as short circuit protection (same as HifiBerry).

The old schematic should also work.

I have attached also the latest one.

Best Regards
Benjamin
Attachments
Rockaberry - v1.0.zip
(44.95 KiB) Downloaded 1256 times

Rene230781
Posts: 11
Joined: Wed Feb 03, 2016 8:01 am

Re: TinyTOSLINK (digital audio output) now for B+, too

Fri Feb 05, 2016 12:42 pm

GREAT!!!

Thanks very much! I will see if I can find the time to build something on a 1 layer board. First will have to collect the parts.


René

[IDC]Dragon
Posts: 41
Joined: Mon Dec 16, 2013 9:47 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Fri Feb 05, 2016 9:06 pm

Hello,

OP here, please forgive my absence, lots of work during the last months, won't get better soon.

TinyTOSLINK started a lot more tiny, for the rev. B board. That's why it is reduced to the minimum component count. No space for series resistors.
http://www.raspberrypi.org/forums/viewt ... 45&t=75225
However, I always had an L/C-filter for the PLL supply, pin 7 PVDD, and a very good clock crystal.
(Later version has 5 extra components for the galvanic S/PDIF out/in.)

The B+ board in comparison is rather spacious. I even was experimenting with small pulse transformers for insulated S/PDIF.

The PLT133/T8 transmitter with the shutter mechanism is kind of tall. It will reach all the way down touching the activity LEDs, perhaps colliding with cabinet lightguards. If anybody wants some, I have a dozen of them left, consider them a mis-buy.
I chose a different part, DLT2153A from Aixin. Very low profile, no shutter, comes with a plug. Extra benefit is that the Aixin transmitters are the rare kind reaching 25 MHz, which is needed for 192kHz/24bit audio. (If the receiver is the same grade.) Really works, I can confirm.
Hard to get, my source only was an AliExpress shop from the manufacturer. Only worth if buying a lot, since they charge about $40 for shipment.

Ben, do you allow some constructive criticism and questions about your board? I'd like to mention:
- Why such big resistors? 0603 would fit be the design well, since Eagle footprints are on the large side anyway, 0805 can be used even on 0603 footprint.
- In contrast, the crystal is really tiny. You should ground the remaining 2 pins, they are connected to the case shield.
- Power traces could be thicker. I hope you have a ground polygon. I've avoided long traces on the bottom side, mine is basically a ground plane, with only a few short traces crossing.
- The split connector makes it difficult to properly align the halves. (They even have different pin counts?) Eagle has huge holes for headers, so they have a lot of play. At least, plug them on the RasPi connector before soldering in, to help alignment.
- Better ground the write-protect line (pin 5) of the EEPROM.
- No need for pullup/down resistors on pin 2 and 5, can directly connect to Gnd and Vcc. I also saved the reset lowpass, just connecting pin 6 to Vcc.
- The transmitter can be powered from the 5V rail, helps to reduce regulator load.
- Why the pullups on the I2C pins of the EEPROM? Is that necessary?
- What is the LED good for?

So far I've published boards and schematics of all my creations, but with TinyTOSLINK I was hesitant, since there is Hifiberry Digi. TinyTOSLINK is no clone, I had it ready before Hifiberry Digi came out, however I've changed the crystal frequeny and I2C address to match it.
Being compatible in this way benefits a lot from the existing software, support and installation instructions for many distros.
Now that the hardware design is kind of public, I'm reconsidering. Anyway, It's not rocket science, one of the most simple boards I've made. The layout was lots of fiddling, especially the tiny rev. B version.

Jörg

NoSpecialSymbol
Posts: 13
Joined: Sat Dec 12, 2015 6:53 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Sat Feb 06, 2016 7:01 pm

Dear Jörg,

thank you very much for your comments and suggestions!

I understand that some of the components (such as the EEPROM and the LED) are optional. As for the 0805 footprints: is there any good reason to use smaller ones (stray capacity etc.)? I see that they are quite large, but they offer a nice option to cross signal lines where needed (they fit underneath the resistor).

From eyeballing the photograph of the board, I'd say that it'll be possible to solder a one-piece 40 pin female connector across the split connectors to avoid mis-placement.

I agree that the oscillator is quite small. I'm not looking forward to the soldering part;-). Benjamin: which component did you foresee for this? I have a CX3225SB. Are the specs of yours (frequency tolerance etc.) different from this one?

Btw., I can't find the CX3225SB's footprint in the Eagle library. Jörg, did you make this component's lib yourself?

Thanks again for sharing your work and insights here. You're making a few DIYers very happy, including me.

Sincerely,
Christian

DonAlwarez
Posts: 1
Joined: Sun Feb 07, 2016 3:17 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Sun Feb 07, 2016 3:35 pm

Hi Benjamin.

Can you send me the PCB and the parts to Austria?

Best Regards, Robert

NoSpecialSymbol
Posts: 13
Joined: Sat Dec 12, 2015 6:53 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Sun Feb 07, 2016 9:27 pm

Dear all,

I'm posting a suggestion for an alternative layout. Differences w.r.t. to the previous layout:

- A massive GND polygon on the bottom layer
- A "rail" for the supply voltage
- The optical transmitter is tied to 5V
- Shorter data lines without vias
- JP2 is to connect a coaxial jack for a SPDIF connection
- SPDIF inputs left out

Please let me know about any comments or suggestions. I'm happy to share the Eagle files if someone wants to work on this.

Thank you!
Christian
Bildschirmfoto 2016-02-07 um 22.24.25.png
Bildschirmfoto 2016-02-07 um 22.24.25.png (59.04 KiB) Viewed 6839 times

Rene230781
Posts: 11
Joined: Wed Feb 03, 2016 8:01 am

Re: TinyTOSLINK (digital audio output) now for B+, too

Mon Feb 08, 2016 1:29 am

Great to see a community helping each other. I would like to see the eagle files.

Thank you Guys for this great work.

René

NoSpecialSymbol
Posts: 13
Joined: Sat Dec 12, 2015 6:53 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Mon Feb 08, 2016 8:46 pm

Dear all,

please find the schematic and the board file for Eagle attached. Note that this layout has not been tested (in fact, it has not even been fabricated yet).

Please review carefully. If you have any comments or suggestions, or see anything suspicious, please take a minute and report to this forum. Thank you very much & happy soldering!

Sincerely,
Christian
Rockaberry_Eagle.zip
Eagle files (board and schematic)
(46.78 KiB) Downloaded 1195 times

[IDC]Dragon
Posts: 41
Joined: Mon Dec 16, 2013 9:47 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Mon Feb 08, 2016 9:52 pm

Christian,

go for a filter on the PLL supply, don't just tie PVpp to 3.3V. If you need space, replace your R1 and R10 with wires. R4, R5, R7 may go, too. R6 and R13 may be omitted, but I admit I've never tested the EEPROM on my board.
A bit of a pity for the missing input.
The board is larger, well.
To improve cabinet compatibility, better cut out the upper left corner, where a mounting bolt may come through.

Jörg

NoSpecialSymbol
Posts: 13
Joined: Sat Dec 12, 2015 6:53 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Mon Feb 08, 2016 10:45 pm

Hi Jörg,

thanks for your feedback! C1 and C2 (next to pins 7 and 19) are supposed to stabilize the IC power supplies. I could think of an additional serial inductor, but that would probably have to go onto the bottom layer, then.

Does any distribution support SPDIF recording yet?

The board dimension is a valid point - I'll either cut the corner or add a hole. I guess I can also shave some mils off the board, but then the Eagle design rule check tells me I'm too close.

Sincerely,
Christian

[IDC]Dragon
Posts: 41
Joined: Mon Dec 16, 2013 9:47 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Tue Feb 09, 2016 9:13 pm

NoSpecialSymbol wrote: Does any distribution support SPDIF recording yet?
Probably all of them do, it's in the driver. Somebody did test it, said it works out of the box.

Jörg

Rene230781
Posts: 11
Joined: Wed Feb 03, 2016 8:01 am

Re: TinyTOSLINK (digital audio output) now for B+, too

Fri Feb 12, 2016 9:18 am

Hi Guys

I got my RPI 2 Modell B here. As well I got the older Hifiberry Digi (not Digi+). Can I adapt the old digi to the new 40 pin header?

Any Ideas? Must not fit into a case. Can as well be wired with cables for about 10cm.


regards
René

[IDC]Dragon
Posts: 41
Joined: Mon Dec 16, 2013 9:47 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Sun Feb 14, 2016 1:31 pm

Rene230781 wrote:I got my RPI 2 Modell B here. As well I got the older Hifiberry Digi (not Digi+). Can I adapt the old digi to the new 40 pin header? Must not fit into a case. Can as well be wired with cables for about 10cm.
That's indeed possible.
In a german forum, I once posted how to wire my previous hardware to the new 40 pin connector:
https://www.mikrocontroller.net/topic/331467#4021082

Jörg

BenjaminKe
Posts: 65
Joined: Fri Jan 15, 2016 2:55 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Mon Feb 15, 2016 9:38 am

Hi All,


First of all: I have my board with the optical output running now on 2 Raspberry Pis and it works perfekt!


It was also very simple to configure:

Just plugging the SD Card of my OpenElec in the PC and adding following 2 lines to the config.txt:

dtoverlay=hifiberry-digi
dtdebug=1

Then I could select the hardware under System - Audio Hardware.


Jörg:

Why I'm using 0805 is more a matter of habit - for 0805 I have lots of parts at home - for 0603 not - this is also one of my first PCBs I ordered - I always made the PCBs at home by myself which is quite hard for small parts or if you go with tracks between the pads of a resistor.

Regarding the crystal:
One of the pins is a GND pin and this Pin is connected to GND - the other pin is a NC pin and should not be connected.
The crystal is a CX2016DB.

Power lines could be a little bit thicker that's true ;)

With the split connectors I didn't have any problems - when I designed it I added first a 40 pin header, then moved the smaller ones above the 40 pin header and then removed the 40 pin header again to be on the safe side that's it's perfectly aligned.
So yes it also also possible to just solder also a 40 pin header.
In my case I need the split connector because I also have a Ambilight connected to these free pins.

For the WP of the EEPROM the best would be to add a mini switch so that the EEPROM is not overwritten - but at the moment it's just optional on the layout and not needed (it's just for future features, because the original HifiBerry Boards also have it).

The pull-ups here are just a short circuit protection, because if you play around with the software or something you might configure the pins which are used here as input as an output.

That's true - The transmitter could be powered also from the 5V supply.

Pull-ups on the I2C line: again I made it the same like the HifiBerry boards (maybe they can be omitted).

The LED is also the same like on the HifiBerry board - but in my case I have not assembled it.


For me it was important that it works with OpenElec and the HifiBerry software/drivers which are implemented there.
That's why I tried to align the hardware with the original HifiBerry boards.


Here a few more pictures of the completed board which is working perfekt:

Image

Image

Image

If someone needs: I still have some PCBs and parts left.

Best Regards
Benjamin

Rene230781
Posts: 11
Joined: Wed Feb 03, 2016 8:01 am

Re: TinyTOSLINK (digital audio output) now for B+, too

Mon Feb 15, 2016 11:13 pm

I may come back to your offer for the board. Will see if I can get mine to work..Actually I used a digi with RPI2. But do not get audio out...

Image

Code: Select all

connect to Rev. B+
 -----------------

 P1:
 3: SDA   grün    -> 3
 5: SCL   gelb    -> 5

 P5:
 1: +5V   rot     -> 2
 2: +3.3V orange  -> 1
 3: BCLK  lila    -> 12
 4: WCLK  grau    -> 35
 5: DOUT  n.c.    -> 38
 6: DIN   weiß    -> 40
 7: Gnd
 8: Gnd   schwarz -> 6
Fullreport is here:
http://www.kodinerds.net/index.php/Thre ... post277034

BenjaminKe
Posts: 65
Joined: Fri Jan 15, 2016 2:55 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Tue Feb 16, 2016 8:37 am

Hi Rene,

On a quick look I think this might be the problem:

The Pin 1 of P5 has a different location on the Pi then on the Digi Board.

If you look at P1 for example:
On the Pi the Pin 1 is on the inner side of the Pi
On the Digi Board it's also on the inner side of the Pi

If you look at P5:
On the Pi the Pin 1 is on the OUTER side of the Pi
On the Digi Board it's on the INNER side of the Pi
1.PNG
1.PNG (59.09 KiB) Viewed 6429 times
2.PNG
2.PNG (55.2 KiB) Viewed 6429 times
The connection table you posted is for the Pin numbering of the Pi.
(I guess the Pin 1 location of P5 on the Pi is mirrored because it was intended to solder it on the bottom side of the Pi.)

So what you need to do is to mirror your P5 connections on the Digi board.

So the new connections would be:
Pi -> Digi
1 -> 1
2 -> 2
6 -> 7
12 -> 4
35 -> 3
38 -> 6
40 -> 5

Best Regards
Benjamin

Rene230781
Posts: 11
Joined: Wed Feb 03, 2016 8:01 am

Re: TinyTOSLINK (digital audio output) now for B+, too

Tue Feb 16, 2016 9:16 am

Hi Benjamin,

thanks for having a look.

Sorry for the follwoing confusing description... :-(

Here you can see pictures of the 2 devices I got. There you can see Pin1 is like I used to do in my wiring diagram (Square Solder Pads). I as well took off all soldered wiring as I now got cables which I can easily connect to the headers without soldering. So I will be able to "play" more around with wiring.

Image

Image

What makes me confusing (even if the square solder point may be confusing):
When comparing the P5 Header Description with the Model B/ B+ Pin- Description. When using my old Pinout I seem to mix the GPIOs as well yours:
my wiring 4 <-> 35 GPIO 18 <-> GPIO 19
your wiring 3 <-> 35 GPIO 17 <-> GPIO 19

Somewhen I read RPI2 uses different GPIOs and foud this:
Image
my wiring would be: 4 <-> 35 GPIO 18 <-> GPIO 24
your wiring: 3 <-> 35 GPIO 17 <-> GPIO 24

Image
http://www.keytosmart.com/wp-content/up ... ksheet.pdf

When wiring as I originally postet the Receiver does not recognize audio at all.
But in the wiring table is:
5: DOUT n.c. <-> 38
If i do not connect (n.c.) the receiver recognices Digital audio and activetes the speakers. Only noise is to hear and changes in sound if I move the digi board.


Thanks

BenjaminKe
Posts: 65
Joined: Fri Jan 15, 2016 2:55 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Tue Feb 16, 2016 12:09 pm

Basically you just need to put the correct GPIOs together.

Maybe it's also easier if you check the connections on the HifiBerry PCB - if you take a look at my schematic I tried to use the same names for the parts like HifiBerry.
So you can just check where for example R7 goes, compare it with my schematic and try to make the same connection.

If you upload another picture, on how you have the connections now I can also help check.

Best Regards
Benjamin

Rene230781
Posts: 11
Joined: Wed Feb 03, 2016 8:01 am

Re: TinyTOSLINK (digital audio output) now for B+, too

Tue Feb 16, 2016 12:12 pm

Out of my brainb! ;-)

Actually I checked the Schematic in Eagle and measured Pin 7 of IC1 to see which Pin is 3.3V.

See here:
Image

So I wired wrong.. Hopefully I did not break the IC by putting 5V instead of 3.3V

Will try later when back from work.

René

BenjaminKe
Posts: 65
Joined: Fri Jan 15, 2016 2:55 pm

Re: TinyTOSLINK (digital audio output) now for B+, too

Tue Feb 16, 2016 12:33 pm

Hi,

This is how you need to connect the 3 datalines:
Image

From this picture the upper side of R2 needs to go to Pin 38 of the RPi.

Pin 1 of the IC needs to go to Pin 5 of the RPi.
Pin 3 of the IC needs to go to Pin 3 of the RPi.

I guess the 5V supply is needed for the transmitter (so don't forget this).

With this configuration it must work.

Best Regards
Benjamin

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