I'm pretty sure that Heimdall is a cool name for a "home watching" device, so it's probably taken and trademarked already. Please don't sue me, I did google for you but I might have failed.
My goal is to hack together something that gives me a false feeling of security for when I'm away for more than a week.
I don't claim to make it smart. It might turn lights on and off over insecure 433 MHz switches. I might add a current meter to log its power.
The echo dot currently runs for 55 Euros and I couldn't resist buying one! The option to chose your own speaker instead of paying 120 Euros more for the full echo was almost reason enough for me - but to my surprise I discovered that the echo dot also has an (admittedly crappy) speaker! It's enough to chat along and use IFTTT with adafruit.io+alexa receipts to switch the lights on by saying "echo trigger Küche ein" etc. - nice!
It took me a while to figure out that the "remote_username" and "remote_password" on my raspberry had to be replaced by "username" and "password", since the mosquitto version on my PI is (still?) too old? [adafruit.io - bridge mqtt] To get some debug informations, stop the mosquitto service and start it as a program.
cd /etc/mosquitto/conf.d/
sudo systemctl stop mosquitto.service
mosquitto -c mosquitto.conf
So this board is supposed to be a stamp "USB to testpoint" connector. But as soon as I ordered the thing I noticed it would totally make sense to add a mosfet for controlling power to it and maybe add the run pin and another dedicated pin for remote shutdown and remote reset. Ah well. Feels like midnight.
This is basically what I'm following to set up the cluster. Meh, so much for me doing the hard work :D Every SD card is flashed on configured (at least that what I hope).
I'm waiting for the currently printing 4th version of my minimal cluster holder.
I think I have the center of the usb plugs and and everything else right, now. This will integrate fine into my cluster build. I've added Letters for USB and Ethernet to not confuse orientation. The SD cards all have to point in the same direction, imo.
The only thing annoying me at the moment is the usb cable management. A self made 4port usb to 4 single micro usb plugs is in development, but for now I use the Anker 15cm cables. There's definitely room for improvement.
For better fitting an angled network cable should be acquired as well :D
I'm still too much of a wuss to solder the usb ports directly and I wan't a clean looking build.
This is my newest attempt on a mac pro inspired design, but this time it's supposed to fit the pi zero cluster. I'm going to make a special usb cable with angled connectors and a self made 2x2 usb connector. The holder for the pi zeros is the third version I'm printing right now. There is a 5x5cm fan planned and also a "16bit" neopixel ring. So this has all the stuff for a rage-filled-comment-filling blog entry:
too many Raspberry PI zeros nobody gets
an ineffective cluster not worth the money for a cluster
a 3D printed case printed with a printer nobody wants to pay for
a fan on a Raspberry PI
too many blinking lights, possibly controlled by an arduino
If I want to use the cluster with the alexa service then I need to find an I2S, SPI or I2C soundcard to get microphone input. I can't really use USB soundcards, since all 4 ports are taken by the 4 PI zeros and vice versa.
pi dac+ and hifiberry dac+ don't have any ADCs but in the datasheet of the used chip 5102A there was also the PCM1863 that might be able to help me out. not sure. Cheapest chip is 5-7euros on ebay.