How to make a PIC-based electronic combination lock
Here’s an awesome DIY electronic project for those of you who know some PIC programming. Based on the 16F84 PIC microcontroller, an 8-bit microcontroller in the PIC family from Microchip, this project makes a simple DIY circuit that checks for combination of button presses to perform an action, such as unlock a door. With slight modifications this project should be adaptable to the more widely available 16F88 with integrated oscillator. There’s also a newer version for the PIC 16F628 with an optional lcd output.