Hackaday projects update: CALE Eink Calendar and udpx

I must say although I’m not proud of all the projects I tried to document in Hackaday I do like a lot udpx and Remora, that are made initially to control Addressable LEDs, but they could be expanded and used for another uses.

CALE

This is actually an old project for the agency I work that is finally seeing the light. I started using Waveshare V1 and this is the new 7.5″ e-Paper V2

CALE E-eink calendar ESP32
CALE Eink calendar ESP32

This will be powered by a TinyPICO ESP32 that claims to consume as little as 20uA when in deepsleep. Let’s see when it’s connected to the Waveshare also in deepsleep ;)
But the idea is to connect, refresh the meeting room labels at each door, and then go to sleep for at least 2 hours. And in wakeup check the day of the week, it it’s Saturday or Sunday when we are not in the office, then just keep on sleeping. There is no need to update stuff when no one will watch.
So designed with low-consumption in mind, will be actually my first real battery project, that I hope last at least 30 days without charging. The Firmware is actually not ultra complicated except the BMP image reading part, that I took mostly from the GxEPD Eink library example, with the add-on that I implemented Zlib compression so download takes one second instead of five. Other than that the only thing that does, is to wake up, query a backend passing an URL that renders that webpage screenshot. The image is sent per SPI and it goes to sleep.
EVOLUTION:
Firmware: 90% done and open source
Case: Work in progress
CLIENT: http://www.skygate.de

udpx

udpx sending frames to a 44*11 RGB Led matrix
One of my personal favorites since we are working in team long time already is udpx which is a transmission protocol with decompression support (Zlib and Brotli)
That we are using at the moment to receive animation frames but I can see much more potential in it, like to be used to send small JSON beacons and have real-time charts for anything, they are endless possibilities to use a streaming technology that is proving to work stable. The Max. transport Unit (MTU) of the ESP32 is about 1470 bytes, but you can send much more in that payload if you use Brotli or Zlib, so I see that it can be applied in many other use-cases.

udpx is the first project using Espressif boards where we can use the full connectivity possibilities that the ESP32 offers:

  1. Bluetooth WiFi configuration. That’s one of the main reasons the ESP32 offers Ble and Bluetooth serial, so here we put it to use.
    udpx-app is an open source Android application that offers Ble/Bluetooth serial configuration to send WiFi credentials and also mDNS discovery using zeroconf
  2. WiFi UDP and decompression. ESP32 has enough memory to pack in one sketch both Brotli, miniz (Zlib) and Bluetooth. I did not believe this initially, but udpx is the proof-of-concept that it can be done.

Pixels is the library that is implemented to do the UDP interpretation, read the headers and send the RGB(w) brigthness values of each LEDs to Neopixels. Initially developed by Samuel our colleague in the USA, we work in team also with Hendrik in Frankfurt am Main to develop a Backend controller that will be able to chain animations and route them to multiple ESP32 controllers every millisecond. So this is a very exciting project, that is going slow because everyone is busy in many things at once, but one that I personally steal hours of sleep every time I can just because it’s interesting and beautiful to work on it.
Last addition was the PIX565 protocol, one that’s been inspired in Spectre’s own take on OctoWiFi LED Controller, but one that has been also used in old game consoles. Didn’t know about this, but Neopixels developer Michael Miller put it in words today:

Games also use alternate bit depth images like 565 and even others; to compress in memory textures. Lots of writeups on that and how shaders can use them to render. The graphics stuff you learn for LEDs often overlaps with gaming techniques.

Remora

This streaming little fish is swimming since a while and I’m proud that some music hackers are using it in professional Eurorack setups.

It was initially built for ORCΛ sequencer, and receives short UDP commands of 4 to 6 characters, to launch fast animations at a very high framerate. In the last months it also had the addition that if receives more than 9 bytes, it renders also a Pixel animation frame, so you could send short animations, but also a small animated video.

Remora was also the first product that I could imagine can be a Tindie product, but I must confess that I never selled one, even that I put a price that is mostly the Hardware price. I’m good at building, but not at selling. Everyone has to find their strong point.