I guess all of you know the boring old business card. Just for fun I decided to create a PCB business card. On the bottom there was more than enough space for the most important data (like Call, Name, Adress, even a QR that leads to my homepage), but I wanted to make efficient use of the space on the PCB's top. So I decided to make a circuit that people can solder together, flash the MCU and have fun using the card ;)
The original idea was to build a business card circuit that has a small LED matrix display.
Due to size constraints and to keep the circuit simple I opted on a 16 x 12 LED Matrix. The columns are driven by 2 cascaded 74HC595 shift registers
and the lines are controlled by a single 74HC154 4 bit binary decoder. The used MCU is an Atmega32U4, which is sufficient, but hella expensive. Power is supplied through a Micro USB jack.
I wanted to run a small game on that system in the first place. To keep controls simple I use 2 potentiometers connected to ADC pins.
One game that originally uses such a controlling scheme is PONG. Programming the game itself was pretty simple, but
the harder part was programming the display logic. There, timing is key. You need to know your timing sequence very well.
I accidentally activated the OE of the line decoder BEFORE setting the line bits and AFTER resetting the line bits. As a result, the screen only displayed
line 1. Programming the rest was pretty smooth sailing though.
--- Placeholder --- When I have the time again I will gladly share some pictures and the demo code.
--- Placeholder ---