Before we all carried supercomputers in our pockets, the Game Boy Camera was a pretty unique proposition. Inexpensive, portable, digital photography — even featuring a selfie mode!  t0mg decided to create their own 1-bit camera add on for Panic’s unique Playdate portable gaming console.

t0mg took advantage of Teensy 4.1’s USB Host capabilities in order to transmit image data via serial, essentially emulating a very strange controller that sends pixels instead of button inputs. Excellent detail about the project can be found on the PD-Camera accessory’s GitHub repo, including a deep dive into how it all works, and a fun overview of its capabilities can be seen in the video below.

T0mg created a Teensy 4.1-based keyboard adapter dock for Panic’s Playdate handheld console, along with an accompanying minimalist word processor app.

The dock uses Teensy’s USB Host capabilities to transmit keyboard inputs as if they were rotations of the Playdate’s unique analogue crank controller — and can actually be used with other USB controllers, like those from 8bitDo. Alongside the Teensy, a small USB hub is concealed in the dock, to allow connection to the keyboard/controller as well as the Playdate itself.

More detail, including firmware and STL files can be found on GitHub, and a nice build thread with videos can be found on whatever the site that used to be called Twitter is called by the time you read this.

IBM introduced the Video Graphics Array (VGA) standard in 1987, improving on EGA’s 16-color graphics with up to 256 colors and a maximum resolution of 640×480.

Inspired by the uVGA library for Teensy 3.X by Eric Prevoteau, PJRC forum user Jean-Marc developed the VGA_t4 library for 4.x boards. With a handful of resistors and 15-pin D-sub connector, your PSRAM’d Teensy 4.x can output 307,200 8-bit pixels of analogue goodness too — perfect for emulators and retrocomputing projects!

While the implementation differs from the original uVGA due to differences between the Teensy 3.x and 4.x hardware, the code should feel familiar to anyone familiar with the uVGA API. The library currently supports 320×240, 320×480, 640×240, and 640×480 resolutions, with experimental support for 352×240, 352×480, 512×240 and 512×480. Sketches must be compiled at 600MHz for accurate timing. The library and source can be found on GitHub, and the video below demonstrates its use to display a Mandelbrot fractal, as well as Amiga Workbench courtesy of Jean-Marc’s MCUME retro emulation project.

Creating a project with Teensy boards is cool, but you know what’s really cool? Creating a project that lets other people, who might not ordinarily be able to approach a microcontroller-based project, build something amazing.

This was Emmanuel Presselin’s goal with the Teensy 3.2-based MiniTouch low-cost synth, targeted for use in workshops with children ten and older.

The MiniTouch consists of two PCBs: one for the FastTouch-powered capacitive-touch keyboard, and one for the Teensy, pots, and mini class-D amp, which is connected to standard 10W TV speaker. The Teensy 3.2’s built-in DAC is used to provide 4-voice polyphony, a band-limited oscillator, ADSR, low-pass filter, filter envelope, LFO, reverb, and portamento effects.

Fifteen presets can be tweaked with a separate app based on Max/MSP. A laser-cut enclosure, batteries, and a handful of knobs give workshop participants something they can be proud of having built, then take home and enjoy further without any specialized tools or knowledge. While Emmanuel has no plans to release the source or build instructions, you can see a great demo of its capabilities in the video below.

We love seeing emulator projects on Teensy hardware, and reproducing the original DMG Game Boy, with its 4MHz, 8-bit CPU, is certainly well within the capabilities of the Teensy 4.1’s 600MHz Cortex-M7.

Forum member blazarious has created an elegant “breadboard Game Boy”, consisting mostly of simple through-hole components, plus a custom board for the 4-inch 480×480 pixel TFT display.

Game ROMs are loaded from the Teensy 4.1’s mSD slot — or more accurately game “ROM” since only Tetris is playable at present. Only three of the four sound channels are currently supported, though that is plenty for the classic Tetris soundtrack to be recognizable in the video below. More info can be found in the project’s GitHub repository, while the display driver library and hardware has its own separate repo, and a series of blog posts detail the project’s progress and evolution over time.

Despite the name, not every project we see using Teensy is necessarily that diminutive.

This adorable pre-amp from Marcell Marosvolgyi shows what’s possible with the small form factor, however, using a Teensy 3.2 plus Audio Shield to provide bass and treble tone control, surround sound processing, and compression, in a gorgeous little enclosure.

Adding a stackable 20-watt amplifier using Adafruit’s MAX9744 breakout board results in world’s cutest hi-fi stack. Project details can be found on Hackaday, with firmware and a Python script that provides a PC interface on GitHub.

Just in time for #MARCHintosh, we present: John Calhoun’s Adam74 mini terminal. With form inspired by the ADM-3A video display terminal, and functionality by the Apple I’s ASCII bus, this diminutive display accepts 7-bit ASCII codes, then renders them on a 3″ LCD.

Based around the Teensy 4.0, the Adam74 incorporates a custom PCB with an ILI9341-based LCD, plus a small speaker in order to enable the BELL control code. Additional codes allow simple cursor movement, with text wrapping and scrolling handled by software on the Teensy.

The complete source, as well as Gerber files and schematic for the PCB, and even an SVG to help recreate the stand, are available on the project’s GitHub repo. An excellent recounting of the project’s genesis can be found on John’s Engineers Need Art blog, along with a number of other unique and interesting, mostly Apple-oriented projects and stories.

We’ve seen some impressive modular synth builds using Teensy boards, but PJRC forum member ghostintranslation took things even further with development of their MOTHERBOARD (MOdular Teensy Hybrid Eurorack Board) modular synth platform! MOTHERBOARD eschews the Eurorack electrical specification, instead relying on MIDI via serial for communication between modules.

Three physical MOTHERBOARD variants, each based on the Teensy 4.0 + Audio Adaptor Board, offer six, nine, or twelve inputs respectively, where inputs might be any combination of pushbuttons, potentiometers, or encoders. Example modules include the SYNTH FM polyphonic synthesizer,

DRONE 4-voice drone, DS909 TR-909-inspired drum synthesizer, PSYC03 Syncussion/TB-303 “acid percussive synth”, CYCLE monophonic sequencer, and BYTE drum sequencer. An API, exposed via the included `Motherboard.h`, allows reading of inputs, setting of LEDs, and handing of MIDI and input callbacks. Firmware and schematics are available on GitHub, with PCBs available on the artist’s Bandcamp page.

 

 

Amateur radio has been a popular hobby for decades, and can be an expensive rabbit hole to fall down.

It’s easy to spend thousands of dollars on equipment, such as the FLEX-6600 series of SDR (software-defined radio) transceivers, and even then you still need a Maestro Control Console or PC in order to interact with it. Unless, that is, you have a Teensy 4.1, the Arduino Flex library, and a little ingenuity, as PJRC forum member KD0RC demonstrated with their TeensyMaestro Controller for Flex 6000 ham radios.

The TeensyMaestro leverages the Flex TCP/IP API to control the transceiver, via an interface built from nine mechanical encoders, two optical encoders, 20 multiplexed switches, and an Adafruit HX8357 TFT touchscreen. The snazzy-looking front panel is simply aluminum covered with laser-printed graphics under a clear plastic shield. A GitHub repo is available with schematic, BOM, builder’s guide, and user manual.

The average Major League Baseball pitcher throws the ball at over 90mph, with the number of 100mph pitches increasing in recent years. But the average cannon…or…well, we’re not sure if it’s average, but this cannon in particular fires balls at up to 135mph…maybe?

Whether or not it does, jpswensen has created an Teensy 4.1-based advanced measurement system that can calculate the velocity of baseballs being shot out of  cannon at up to 135mph!

The system consists of four emitter boards and four sensor boards. Each emitter is comprised of 34 laser diodes, with a corresponding 34 PIN photodiodes and transimpedance amplifier circuits on each sensor board being read by a Teensy 4.1. The Teensy-powered sensor boards are in turn connected via I2C to a Raspberry Pi 4, which performs the necessary calculations to determine the incoming and rebound velocity. Watch the whole system in action in this super-slow motion video.