Smart Key Chain:
Status: work in progress
Tags: AVR, E-Paper, 3D Print
Year: 2023
A normal keychain is boring, so I thought I’d make a unique one. I wanted to do something with an e-paper display for a long time, that’s how I got the idea for this project. Thanks to the use of such a display the keychain is extremely lowpower. This allows the keychain to be used for a long period of time without having to recharge it.
There are two modes available to adapt the usage according to the user.
Either the display is updated once per minute, or the display is updated only at the press of a button.
LED Matrix:
Status: finished
Tags: Raspberry Pi, AVR, ESP8266
Year: 2021
I was able to save this LED matrix from the trash. The control board was completely outdated and undocumented. Through reverse engineering I was able to reconstruct the protocol interface and was able to get it running again.
How it works:
Various sensors collect data about weather, air quality and more. This data is then sent from ESP8266 microcontrollers over WLAN using the MQTT protocol to my home server. Here the data is then stored in a SQL database. The Raspberry pi in the LED matrix receives this data from the home server and creates a pixelmatrix. This pixelmatrix is then forwarded to the microcontroller via UART. The microcontroller drives the matrix itself and draws this information on the display.
Depending on the brightness in the room, the display switches into a night mode to avoid illuminating the whole room. In night mode, only a small time is displayed and the brightness of the display is reduced using a PWM.
LED Panel:
Status: finished
Tags: Raspberry Pi, AVR, ESP8266
Year: 2019
The idea of this project was to create a panel on which everyday notes and to-do lists can be made. Anyway, since a normal whiteboard is pretty boring, I decided to make it more exciting.
How it works:
The keypart is the wifi-module ESP8266. It creates a webserver that hosts a website in my local network. A device in the same network, can access the website through the IP 192.168.1.200. When a color is choosen, the color is send over an websocket from the website, to the ESP8266. This then changes the color of the led strip. The only thing that now needs to be done, is to make notes with a white crayon marker. The notes can simply be erased again with a wet towel.
To prevent the panel from running 24/7 it is turned off by my home server at night and when I am not at home. The home server checks once a minute via bluetooth if the MAC address of my smartphone is nearby.
