A microcontroller-based affection-giving MACHINE!
Important
This project is currently a work-in-progress, there will be things that don't work, please bear with me will I work out the kinks!
The PCB files can be found here, be sure of order a solder stencil too(ideally with a stencil unless you love hand-soldering 200+ SMD connections). The BOM will provide you with a list of parts required. Due to the limited size on the PCB, many of the reference designators have been removed to save space. Because of this, you will likely need to have KiCAD running as you are placing components. Or you can guess I suppose...
You will need access to an ST-Link programming device and have stm32-for-vscode extension installed. Once you're ready, upload the code by:
- Cloning the repository
- Open in VS code
- Connect the ST-Link programmer to your computer
- Connect the µAffirmations' programming port to the ST-Link programmer
- Ensure the µAffirmations board is powered
- Open the STM32 for VS Code extention
- Click Flash STM32
This device allows the user to create their own custom messages to be displayed on the LED matrix, to provide your messages, modify the following code found in this file.
For axample:
__weak const char *messages[] = {
"This is the first custom message!",
"Below is a list of supported characters...",
"!\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~"
};
 Programming port broken in RevB of the PCB |
Hardware RevD
After considerable development to the code, I found out that I had not connected the supercapacitor voltage sensing circuit to a ADC capable pin, this has been corrected.
Hardware RevC
After futher testing the following fixes to the hardware design have been made:
- The programming port has been connected to the correct pins on the mircocontroller
- The layout of the components has been adjusted for easier access to the push button
- The supercapacitor management circuit has been de-routed as per the spec sheet
- I added a QR to the PCB, because I could...
Hardware RevB
After hardware tesing the following fixes have been made to the hardware design:
- Supercapacitor charging circuit, now uses a dedecated IC
- LED matrix layout, the LED spacing has been decreased
- LED brightness was assessed and appropriate resistor have been selected
- The overall PCB dimentions have shrunk to 70x40mm
 RevB PCB |
Hardware RevA
Initial hardware design.
See licence for in depth info.
If you'd like to get in touch, feel free to reach out!
