[Kickstarter] Audio Injector Octo: RPi HAT with 6 I2S channels in, 8 out

22. Januar 2017 at 18:27 #26201

M2P users may be interested in this apparent world first: a Raspberry Pi sound card with the ability to push 6 channels of audio into the I2S GPIO pins and output 8 channels!

It seemed like an impossible task. To get more the two audio channels into and out from the Pi over the GPIO header. Lots of people wanted that functionality but no one could work out how to do it. I decided this product would have the potential to completely enable and transform other peoples projects. Not only that if it could be done on the Pi, it could be done on most other embeeded boards. It would empower people by solving what seemed impossible. Beyond that the outcomes for the developing world would be to put an ultra low cost multitrack recorder into the hands of people who otherwise may never be able to afford it – a sub $150 professional grade multitrack recorder. Who knows what people would invent with it !

I put together a plan and began hacking from paradigm to paradigm, making small incremental steps. It felt like I was building a rocket going to the moon for the first time ! No one ever thinks of low level hardware/software hacking as sexy, so it never makes the news

After months and months of struggling, first with purely analogue electronics, ECL logic and all sorts of tricks, I got really close. Sooo close I could sense the signals were going in the right direction – it just needed a little more. But that little more certainly wasn’t going to come from analogue electronics alone. I had to change directions.

I decided to learn VHDL and started using FPGAs. I watch over my daughter (on the weekends) whilst she slept, I would read free range VHDL on my phone or laptop, gradually grasping this non procedural way of „the hardware“. Finally after months, at the digital hardware level I was able to get 8 channels of audio into and out from the Pi hat. Eureka! It is incredibly reliable. So functionally attractive and reliable that it had to be let out of the box ! And so it began ….

[aaron premium]

aaron premium

5. Mai 2017 at 0:06 #28711

I bought the audioinjector not the Octo, with the idea that I could play my LP records in different rooms. I have not been able to get it to work. Admittedly I really don’t know what I am doing.

I was able to install the deb and successfully ran the audioInjector-setup.sh. And when I run the audioInjector-test.sh I hear the tones through the rca outputs.

However I cannot get audio to pass from the rca in to the rca out. Also when I try to airplay to the max2play rasPi (yes it shows up in itunes) no audio either on the rca output, either of the headphone jacks, nor hdmi.

Any insight and assistance would greatly be appreciated!!

5. Mai 2017 at 11:26 #28714

Yet to receive my Octo. Expecting it next week hopefully. Have you tried the forum here:

http://www.flatmax.org/phpbb/viewforum.php?f=5