In the great spirit of fixing something that is not broken, this is how I burned Jussi’s NAA BBB image onto the eMMC so that it could boot from it and we could ignore my growing collection of micro-SD cards.
Leave the BBB connected to the Ethernet, but disconnect it from your DAC.
First step is to boot the BBB off the Debian micro-SD I created in a post above. Now that I have burned 0s into the eMMC I can do that without holding down the Boot button. If you haven’t done that, then you will need to hold down the Boot button as power is applied in order to boot from the micro-SD.
PuTTY in and login as Root (I haven’t given Roon a password yet, I know this will make any Linux folks out there grimace).
Next we need to update the Debian system. The command to do that is:
sudo apt-get update
This will cause the Debian system to update itself and result in a fair bit of package download and reporting to the screen
Now we want to install the utility unzip, so we can unzip the file we will be downloading:
sudo apt-get install unzip
Again a bit of reporting as the appropriate package is installed.
Then we want to get the NAA BBB image zipfile from Jussi’s site (thanks @RBM):
wget https://www.signalyst.eu/bins/naa/v3/images/naa-311-beaglebone.zip
After the zipfile has been downloaded we unzip it with our newly installed unzip command:
unzip naa-311-beaglebone.zip
This will inflate the file we want: naa-311-beaglebone.img
Lastly we write that file to the eMMC (adapting the dd command we used above):
dd if=naa-311-beaglebone.img of=/dev/mmcblk1
It will take about a minute to write the image to the eMMC. It is important not to power off the BBB while it is writing to the eMMC.
After you get a report that 134 MB have been copied then shutdown the BBB:
shutdown -P now
Close PuTTY, eject the Debian micro-SD, connect it by USB to your DAC and reboot the BBB.
It won’t show any boot lights but the Ethernet lights should come on indicating a signal is being received and you should also see it’s IP address come up in the Network Naming tool in HQP. Once renamed it will be available under that name to select as an output device in HQP settings.
Listening at the moment and enjoying it greatly. Can’t tell any real SQ change, but it boots fast and doesn’t have the artifacts of the Pi. I’m going to go out on a limb and say that a BBB booting Jussi’s NAA image is about as inexpensive and minimal as a computer connected to your DAC is likely to get. Powering it from a LiPo battery will keep it noise free also. It’s a pretty good solution and within anyone’s reach, with a small amount of Linux fun thrown in.
One final point, I’d recommend powering down the BBB by holding down the Power button on the board. I have a case that lets me press it through a cutout. That will minimise the risk of corrupting the eMMC which would require us to rewrite the image.
Thanks to @jussi_laako, @RBM, @Rik and @IanM for your help and suggestions. We got there in the end !