Hey there FPGA lovers! The human eye is far from being perfect, and this imperfection helps us in coming up with a lot of ideas and products (take the television for example!). Today’s post exploits the Human eye’s persistence of vision to build a globe of persistence using FPGA. These globes can be used to build circular LED displays using just 1 column of LEDs which make them highly cost effective and fun to build with FPGA.
The trick when it comes to the globe of persistence is to balance the RPM of the globe and the timing of the LEDs switching colour. The author has shared details regarding the hardware needed for the project in the introduction. An FPGA board (you may need to adapt yours for this project), a neopixel 12 LED strip, a 12 wire slip ring, a photo interrupter and a photo interrupter breakout board, a 12V DC motor, a micro SD card and a cross compiler for ARM processors.
The project also needs an interfacing board for the FPGA and globe which has been explained in step 2. Building the globe’s mechanical structure with the DC motor has been explained in detail in step 5, and soldering the wires in the right way has been shared by the author too.
The author has gone to great lengths to explain how to execute the project. Step 1 gives complete details about generating an FSBL file and a PDF in case you have doubts. The coding for the project has been done in Linux. But even if you are unfamiliar with Linux, the author has explained Linux for FPGA in detail in steps 3 and 4. The code has been broken down to modules, and there are clear instructions available on how to program the FPGA. Step 7 is the final step that explains how to get your globe working, and also gives details regarding building custom applications using the globe of persistence and FPGA.