The Better RetroPie Handheld

The Raspberry Pi has become the best video game console on the planet. With RetroPi, anyone can play Super Mario 3, Doctor Mario, and even Doki Doki Panic. Adafruit’s PiGRRL Zero and [Wermy]’s reconfabulation of an old brick Game Boy to house a Raspi Zero and display have made the Raspberry Pi portable, along with all those retro games we love so dearly.

There’s a problem with these builds, though. They only use the Raspberry Pi Zero, and with that the limitations on emulation performance, and the Raspi 3 is far too big for a portable console. What’s the solution? It’s the greatest homebrew console ever created. For this year’s Hackaday Prize, [DeanChu] is building the Retro-CM3. It’s a retro handheld with a 3D printed enclosure, that’s powered by the Raspberry Pi Compute Module 3. Stand back, folks. We have a winner that will top the Raspberry Pi and 3D printing subreddits.

The key feature for this build is, of course, the raw processing power of the Raspberry Pi Compute Module 3. This is a Raspberry Pi 3 with 4 GB of eMMC stuffed onto a board that fits into an SODIMM socket. The pins on this device give you access to the GPIOs and the DSI connector. All you really need to turn this into an amazing vintage emulation console is a breakout board with a few buttons, power supply, and a display.

The extra components for this build include a 3.2 inch LCD using the DPI interface. There’s a speaker, and a 2000mAh battery. The real tricky part here is the custom PCB, breaking out the DPI pins on the Compute Module, adding a small speaker, and throwing a small STM32 to read the buttons. It’s an entire system, ready to be housed in a 3D printed enclosure.

This is, simply, the best Raspberry Pi portable you’ll ever see, at least until we get a Rasberry Pi Zero with the capabilities of the Pi 3. It’s an excellent use of the very small Compute Module, and one of the most polished Hackaday Prize entries we’ve seen thus far.

Circuit-Sword Delivers Retro Justice

You can’t search for “retro gaming” without hitting a plethora of single board computers attached to all manner of controls, batteries, etc. Often these projects have an emphasis on functionality above all else but [Kite]’s Circuit-Sword is different. The Circuit-Sword is the heart of a RaspberryPi-based retro gaming machine with an enviable level of fit and finish.

Fundamentally the Circuit-Sword is a single board computer built around a Raspberry Pi Compute Module 3. We don’t see many projects which use a Compute Module instead of the full Pi, but here it is a perfect choice allowing [Kite] to useful peripherals without carrying the baggage of those that don’t make sense for a portable handheld (we’re looking at you, Ethernet). The Circuit-Sword adds USB-C to quickly charge an onboard LiPo (rates up to 1.5A available) and the appropriate headers to connect a specific LCD. The Compute Module omits wireless connectivity so [Kite] added an SDIO WiFi/Bluetooth module. And if you look closely, you may notice an external ATMega mediating a familiar looking set of button and switches.

Optional Drill Holes

We think those buttons and switches are the most interesting thing going on here, because the whole board is designed to fit into an original GameBoy enclosure. It turns out replacement enclosures are available from China in surprising variety (try searching for “gameboy housing”) as are a variety of parts to facilitate the installation of different screen options and more. One layer deeper in the wiki there are instructions for case mods you may want to perform to make everything work optimally. The number of possible options the user can mod-in are wide. Extra X/Y buttons? Shoulder buttons on the back? Play Station Portable-style slide joysticks? All detailed. For even more examples, try searching the SudoMod forums. For example, here’s a very visual build log by user [DarrylUK].

The case mod instructions are worth a glance even if you have no intent to build a device. There are some clever techniques to facilitate careful alignment of buttons and accurate hole drilling. Predicting their buyers might want a variety of options, [Kite] added reference drill holes in the PCB for the builder to re-drill for mounting buttons or joysticks. To facilitate adding status LEDs externally there is a tiny PCB jig included. There are even instructions for adding a faux game cartridge for the complete look.

If you want to buy one (we certainly do!) [Kite] does group buys periodically. Check out the wiki for links to the right interest form.

Thanks [Speednut Dave] for the tip!

Filter Your Pi And Be A Responsible Pirate

At this point it’s pretty well-known that you can tack a long wire to the Raspberry Pi’s GPIO, install some software, and you’ve got yourself the worlds easiest pirate FM radio station. We say that it’s a “pirate” station because, despite being ridiculously easy to do, broadcasting on these frequencies without a license is illegal. Even if you had a license, the Raspberry Pi with a dangling bit of wire will be spewing out all kinds of unintentional noise, making it a no-go for any legitimate purposes.

Unfiltered output of Pi broadcasting on 107.3 MHz

In an effort to address that issue, [Naich] has written up a couple posts on his blog which not only discuss why the Pi is such a poor transmitter, but shows how you can build a filter to help improve the situation. You’ll still be a lawless pirate if you’re transmitting on FM stations with your Pi, but you won’t be a filthy lawless pirate.

In the first post, [Naich] shows us exactly what’s coming out of the wire antenna when the Pi is broadcasting some tunes on the default 107.3 MHz, and it ain’t pretty. The Pi is blasting out signals up and down the spectrum from 50 MHz to 800 MHz, and incredibly, these harmonics are in some cases stronger than the intentional broadcast. Definitely not an ideal transmitter.

[Naich] then goes on to show how you can build a DIY filter “hat” for the Pi that not only cuts down a lot of the undesirable chatter, but even boosts the intended signal a bit. The design is surprisingly simple, only costs a few bucks in components, and conveniently is powered directly from the Pi’s GPIO. It even gives you a proper antenna jack instead of a bare wire wound around a header pin.

We’ve seen plenty of projects utilizing the Raspberry Pi FM transmission hack, and while this mod still doesn’t make it perfect, it’s always nice to see an awesome hack made even better.

It Looks Like A Nintendo, But It’s Running A Pi: A Gamer’s Long-Sought Dream Handheld

[Christopher Foote] didn’t play quite as many games as he wanted to as a child. After years of catching up using the RetroPie and the PiGRRL 2, it was when he first picked up a Switch’s joy-cons that inspiration struck. Behold: the PiSwitch!

Realizing they operated on Bluetooth tech, [Foote] spent a fair chunk of time getting the joy-cons to properly pair to the Raspberry Pi 3 and function as one controller. Once done, he relied on Linux Joystick Mapper to manage the keybindings with some extra legwork besides to get the analog sticks working properly.

To make this console mobile, he’s packed a 6600mAh battery and Adafruit Powerboost 1000c into the device, added a second headphone jack and speaker for commuting and home enjoyment, and a Pi V2 camera module. A 3D printed case, encapsulating these components and a seven-inch touchscreen, also allows the joy-cons to be detached — though he plans on updating its design in the future.

The PiSwitch boots into a custom UI  that lets you select different services — RetroPie, Kodi, Debian, and the terminal — while the joy-cons seamlessly function together or individually regardless of the activity. Check out the quick intro tour for this project after the break!

Continue reading “It Looks Like A Nintendo, But It’s Running A Pi: A Gamer’s Long-Sought Dream Handheld”

Iron Man Mask With A HUD!

At some point, a child will inevitably dream of being a superhero. Not all children get the chance to see that dream made manifest, but a few take that destiny into their own hands. Redditor [Lord_of_Bone] — seizing at that goal — has built himself an Iron Man mask with an integrated HUD!

Relying on a conceptually similar project he’d previously built, much of the code was rehashed for this ‘Mark II’ version. Pieces of a smartphone holo pyramid act as projection surfaces — using a lens to focus the image to be viewed at such close distances — and a pair of OLED screens displaying the information. It’s a happy bonus that the lack of backlight results in only the text showing in the user’s field of view.

Instead of speaking with J.A.R.V.I.S., [Lord_of_Bone] is using a Raspberry Pi Zero W as the mask’s brain. Working past some I2C troubles between the OLED screens and an Enviro pHat required a whipped-up veroboard and a bit of hardware hacking. Cramming everything into the mask was no easy task — using Blutack and Sugru to bind them in the limited space — but the pHat had to be surface-mounted in the open anyways for atmospheric and light data.

Continue reading “Iron Man Mask With A HUD!”

3D Printed Raspberry Pi NAS With Dual Drive Bays

While it might not pack the computational punch you’d usually be looking for in a server platform, you can’t beat how cheap the Raspberry Pi is. As such, it’s at the heart of many a home LAN, serving up files as a network attached storage (NAS) device. But the biggest problem with using the Pi in a NAS is that it doesn’t have any onboard hard drive interface, forcing you to use USB. Not only is this much slower, but doesn’t leave you a lot of options for cleanly hooking up your drives.

This 3D printable NAS enclosure designed by [Paul-Louis Ageneau] helps address the issue by integrating two drive bays which can accommodate 2.25 inch laptop hard disk drives and their associated IB-AC6033-U3 USB adapters. The drives simply slide into the “rails” designed into the case without the need for additional hardware. There’s even space in the bottom of the case for a USB hub to connect the drives, and a fan on the top of the case to help keep the whole stack cool. It still isn’t perfect, but it’s compact and doesn’t look half bad.

The design is especially impressive as it doesn’t require any supports, an admirable goal to shoot for whenever designing for 3D printing. As an added bonus, the entire case is designed in OpenSCAD and licensed under the GPL v3; making modification easy if you want to tweak it for your specific purposes.

This certainly isn’t the strongest Raspberry Pi enclosure we’ve ever seen, that title would have to go to the ammo case that does double duty as a media streamer, but looks like it would make a great home for that new 3 B+ you’ve got on order.

Look Upon Eyepot, And Weep For Mercy

Hope you weren’t looking forward to a night of sleep untroubled by nightmares. Doing his part to make sure Lovecraftian mechanized horrors have lease in your subconscious, [Paul-Louis Ageneau] has recently unleashed the horror that is Eyepot upon an unsuspecting world. This Cycloptic four legged robotic teapot takes inspiration from an enemy in the game Alice: Madness Returns, and seems to exist for no reason other than to creep people out.

Even if you aren’t physically manifesting nightmares, there’s plenty to learn from this project. [Paul-Louis Ageneau] has done a fantastic job of documenting the build, from the OpenSCAD-designed 3D printed components to the Raspberry Pi Zero and Arduino Pro Mini combo that control the eight servos in the legs. If you want to play along at home all the information and code is here, though feel free to skip the whole teapot with an eyeball thing.

A second post explains how the code is written for both the Arduino and Pi, making for some very illuminating reading. A Python script on the Pi breaks down the kinematics and passes on the appropriate servo angles to the Arduino over a serial link. Combined with a web interface for control and a stream from the teapot’s Raspberry Pi Camera module, and you’ve got the makings of the world’s creepiest telepresence robot. We’d love to see this one stomping up and down a boardroom table.

Seems we are on a roll recently with creepy robot pals. Seeing a collaboration between Eyepot and JARVIS might be too much for us to handle. Though we have a pretty good idea how we’d want to control them.