Tag Archives: S/PDIF

Experimental XBMC build with digital out of AC3 and DTS over SPDIF

imgresDom Cobley was again working on XBMC and the HiFiBerry Digi. There is now an experimental build that supports AC3 and DTS bitstream output. That means you can now send Dolby Digital and DTS soundtracks to your home theater amplifier over an coax or optical link.

The OpenElec build can be downloaded from here: https://dl.dropboxusercontent.com/u/3669512/temp/OpenELEC-RPi.arm-devel-20140308190048-r17871-g8a2f22b.tar

Note that this is again a very experimental setup. It needed a hack in the XBMC code. This must be fixed in the ALSA driver. While we will work on this, we can’t say, when we will be able to change this.

Check out this article how to configure it. Note that for the HiFiBerry Digi you need the following module configuration:

cat >/storage/.config/modules-load.d/hifiberry.conf  <<EOF
snd_soc_bcm2708
snd_soc_bcm2708_i2s
bcm2708_dmaengine
snd_soc_wm8804
snd_soc_hifiberry_digi
EOF

HiFiBerry Digi pre-order started

hifiberrydigiOur new digital output board for the Raspberry Pi – the HiFiBerry Digi. can be pre-ordered now for our a special introductory price. We expect to ship the first units about mid of February.

The HiFiBerry Digi adds an optical and a fully isolated electrical output to your Raspberry Pi. Samples rates up to 192kHz/24bit are supported on both outputs.

Linux driver development has been finished already, production samples were tested. Everything works very well.

Pre-order it now!

HiFiBerry DAC + Digi on the same Raspberry Pi

A HiFiBerry DAC owner asked us, if it is possible to mount the DAC and the Digi board onto the same Raspberry Pi. Sounds crazy? Cool! We thought about it. With one board running as the I2S master and the other as slave, this could work. Let’s test it:
HiFiBerry DAC and Digi
And yes, it worked!

Note: This does not mean, that you can stack any I2S sound cards on the Raspberry Pi. It works here, because one board acts as the master (the Digi) and the other as slave. Also the configuration is a bit tricky. Only the HiFiBerry Digi is configured as a sound card. Linux doesn’t know, that there is another card connected.

P.S. We’re in the last phase of the HiFiBerry Digi production tests. Everything looks good at the moment.

HiFiBerry Digi support in Raspberry Pi Linux kernel

hbdigi-proto-raspberryOur HiFiBerry Digi will be available soon. Now, another major step in development has been finished: The HiFiBerry Digi support is included in the official Raspberry Pi Linux 3.10 kernel. If you’re interested in the source code, check out the pull request on Github.

I want to thank Florian Meier – the author of the Raspberry Pi I2S kernel module – for his great support. During the last weeks, I learned a lot about GIT and Linux kernel patches.

HiFiBerry Digi Linux driver

tux_enhanced_penguin_linux_art-1979pxThere wasn’t any hardware development news in the last time. The reason for it was mostly that we spent time developing a Linux driver for our new HiFiBerry Digi S/PDIF output board. And finally the first working version is there. Getting around the mixer controls and the power management (we don’t need both) took us some time. I want to thank Florian Meier personally for the tips he gave during the driver development phase.

Do you want to test if you can compile it yourself? You can download the code from Github (the new driver is in the 3.10 branch).

Dolby Digital and DTS bitstream output with HiFiBerry Digi

The HiFiBerry Digi driver is still in development. Stereo output works great even at highest sampling frequencies and bitrates (192kHz/24bit). Today we tested what happens, when we output a DTS or AC-3 bitstream through the HiFiBerry Digi. Would an external decoder recognize the signal? See yourself:

yamaha-dd yamaha-dts

It worked :-) That means there is a good chance, that DTS and AC-3 output will be supported. However, we don’t know yet if standard software like XBMC will be able to use the HiFiBerry Digi.