[Hari Waguna] wanted to build a computerized Sudoku game. Ordinarily, that wouldn’t be a big deal. You can buy one, of course, but what fun is that? There’s plenty of apps for phones, but again, not much of a challenge. If you want to preserve your hacker cred, you’d use a CPU board like an Arduino or a Raspberry Pi with an LCD screen, right? But if you want to grow your hacker cred, you’d follow [Hari’s] lead and use 81 seven-segment displays and a membrane keyboard.
Driving that many displays takes some doing (in this case shift registers). [Hari] uses some other tricks, like reading the keyboard using a single pin (and a resistor network). He’s made several videos about the project, including the one below.
Continue reading “Handheld Sudoku (Assuming You Have Large Hands)”
As things get busy, whether it be an upcoming product launch, a pregnancy, or even the release of your favorite game (or movie!) sometimes it’s nice to have a little countdown timer. Not an app on your phone, but a tangible, physical timer to set on your desk. Which is why SevenSeg is such a cute idea.
[Mohit] wanted to design something that was simple, but aesthetically pleasing — he’d seen free-form electronic projects before and wanted to give it a shot. What he came up with is pretty elegant! A seven segment display is connected via 1/32″ brass rods to the controller, a Particle Photon — which is kind of like a Teensy with WiFi for the internet of things. After putting a few resistors in line with the display, and a bit of frustrating bending of wire later, and SevenSeg was complete.
Continue reading “Cute Countdown Timer Reminds you of Impending Doom”
[Esai] wanted to build an electronic clock from scratch. A noble quest, but ordinary seven-segment displays are just that – incredibly ordinary. Instead of a few displays that can be bought from the usual retailers for a dollar a piece, [Esai] made his own four digit, seven-segment display on some perfboard.
Before soldering 58 SMD LEDs to a small rectangle of perfboard, [Esai] traced out each segment with a marker. Two LEDs make up each segment, and they’re all connected to a breadboard-friendly pin header with 30 gauge wire.
Each segment is connected as a single column in the LED matrix, and each digit is a row. It’s a simple design, but there aren’t any resistors on this board. Hopefully [Esai] will be using a proper LED driver with this display; you really don’t want LEDs to burn out twice a day at 1:11.