Logic Lab Trainer
Learn AND, OR, NOR, and more with David Johnson-Davies' logic gate trainer.
Logic gates – AND, OR, NOR, XOR, and the like – are the basis for modern computing. Gates are easy enough to understand by themselves, multiple devices working together quickly turns into a more complicated situation. To help teach this concept to a friend’s son, David Johnson-Davies created the Logic Lab trainer PCB with 12 logic gates that are connected together using patch cables.
The Logic Lab features two each of AND, NAND, OR, NOR, XOR, and NOT gates, with input and output male header pins for connections. Four variable logic sources are used, with slider switchs to set conditions for the newly created computer. Five output lights show the results. Rather than simply providing a sandbox for experimentation, Johnson-Davies also published a number of logic puzzles, complete with an estimated difficulty rating. Answers will be provided in a week.
On the back of this trainer PCB, the device mounts a microcontroller to handle the actual logic. While Johnson-Davies considered using 74LVC series logic gates, he instead used a 48-pin microcontroller to emulate these functions. This reduced the parts count, and allows for reconfiguration if needed without resoldering everything. An ATmega4809 and an AVR128DA48 were used in the prototypes, though a number of other microcontrollers should also be usable.
The Logic Lab is powered by two AAA batteries, and looks like an excellent portable learning tool. Code, board files, and more info is linked in the project write-up if you’d like to make your own.