[deshipu] aka [Radomir Dopieralski] has been building educational handhelds for a good part of a decade now, and knows how to design hardware that makes for effective teaching. Today, we are graced with the PewPew LCD project, latest in the PewPew student-friendly handheld series, powered by CircuitPython.
The goal for all of these devices has been consistent — making game programming accessible and fun. This time, as an entry in the Reuse, Recycle, Revamp round of Hackaday Prize, the new PewPew receives an upgrade – from an 8×8 LED matrix to an LCD display. This might not sound like much, but the change of display technology itself isn’t the main point. [deshipu] is working on ways to bring down the price and assembly complexity of PewPew handhelds, and he’s found there’s plenty of old stock RH-112 displays, previously used on cellphones like Nokia 1202, which these days go for as little as $1.30 a piece.
It’s exceptionally simple to get into writing games for the PewPew – one of the reasons why it’s a strong platform for workshops and individual learning. There’s already a slew of games and tutorials, and we can’t wait to see all the cool games people can build when given all the extra pixels! And, of course, we appreciate setting an example for giving new life to old displays – displays that’d otherwise inevitably end up in a trash container behind a warehouse in China.
The Reuse, Recycle, Revamp Hackaday Prize 2022 round is going on for two more weeks. If you’re making good use of something that would otherwise be discarded, please do share it with us, so that we can all learn and draw inspiration from your projects!
These days everyone’s excited about transparent OLED panels, but where’s the love for the classic Nokia 5110 LCD? As the prolific [Nick Bild] demonstrates in his latest creation, all you’ve got to do is peel the backing off the the late 90s era display, and you’ve got yourself a see-through cyberpunk screen for a couple bucks.
In this case, [Nick] has attached the modified display to a pair of frames, and used an Adafruit QT Py microcontroller to connect it to the ESP32 powered ESP-EYE development board and OV2640 camera module. This lets him detect QR codes within the wearer’s field of vision and run a TensorFlow Lite neural network right on the hardware. Power is provided by a 2000 mAh LiPo battery running through an Adafruit PowerBoost 500.
The project, intended to provide augmented reality reminders for medical professionals, uses the QR codes to look up patient and medication information. Right now the neural network is being used to detect when the wearer has washed their hands, but obviously the training model could be switched out for something different as needed. By combining these information sources, the wearable can do things like warn the physician if a patient is allergic to the medication they’re currently looking at.
The LCD displays for Nokia phones have seen a ton of use as easily interfaced displays for Arduino or other microcontroller projects. Usually, these LCDs are only used for displaying a few lines of text, or if someone is feeling really fancy, a small graph. Shame, then that we don’t see more complicated and computationally difficult tasks like playing video very often. [Vinod] sent us his way of playing video on these small color screens, surprisingly using only an ATMega32 microprocessor.
The build started off by saving uncompressed image data on an SD card using code from a previous project. [Vinod] was able to write a slideshow program to go through the SD card one file at a time and displaying each image. From there, it was simply a matter of using a Python script to convert frames of an .AVI video file to an uncompressed image and display them at 15 frames/second.
Turning these videos into talkies was a bit of a problem, but after taking an uncompressed .WAV file and sending that to a PWM pin on the ATMega, [Vinod] managed to play sound alongside his video.
The result is the ability to play a video with sound at 15 frames a second and a 132 x 65 resolution. You can check out the demo video after the break.
LCD displays taken from old Nokia phones have been a staple of the hardware makers for years now, so we’re very happy to see [Andy] reverse engineering a full color QVGA display so we can move our grayscale projects over to a full-color display.
The screen in a Nokia 2730, 5000, and 7100 cell phone is a wonder of technology – its 18-bit color with a very high-resolution piqued [Andy]’s interest. He bought a second-hand Nokia 2730 off of eBay and started taking it apart. After checking out the schematics for the phone, [Andy] had a few breakout boards made; especially useful since he found a few connectors as well.
With a great deal of Googling, [Andy] found another lost soul who successfully broke into a similar LCD display and discovered it was command-compatible with a Magnachip LCD controller. The only way forward was to send a few of these commands over to the display and watch what happens.
[Andy] managed get pixels drawn on the screen, and found a few interesting features: hardware scrolling is enabled, as is changing between portrait or landscape orientations. From a second-hand phone on eBay, [Andy] now has a very nice QVGA display. We’re calling this a win, but you can judge the video after the break for yourself.
Who hasn’t thought about turning a 1950s slide projector into a digital projector? [Matt] did, but unlike most of us, he actually did it.
[Matt]’s friend [Angus] found an old, single-slide, sans-carousel slide projector in the trash. It’s a wonderful piece of ancient technology with a fabric insulated power cord and bakelite lamp socket. This projector was upcycled to the 21st century by adding a 10 Watt LED and a Nokia 1200 LCD.
For the electronics, [Matt] used an ATmega88 microcontroller. There’s an infrared receiver so the remote from an in-car CD player can be used to advance the slides and turn the projector on and off. The LCD is controlled by a bit of bit-banging from the Mega88, using hard-coded images of Che Guevara, Hendrix, Space Invaders and some old-school Macintosh/Lisa icons. Unlike the screen printed t-shirts at American Apparel, Che is the only authentic image in this project; this projector might have been made after Guevara came to prominence.
With a 10 Watt LED, it’s not the brightest projector on the planet and the picture is a little washed out in a bright room. With dim lighting, it’s a very good project even if the images are static.