Microgamer Is A Micro:Bit Handheld Console

The BBC micro:bit single board ARM computer aimed at education does not feature as often as many of its competitors  in these pages. It’s not the cheapest of boards, and interfacing to it in all but the most basic of ways calls for a slightly esoteric edge connector. We’re then very pleased to see that edge connector turned from a liability into a feature by [Fabien Chouteau] with his handheld console, he uses micro:bits preprogrammed with different games in the manner of game cartridges in commercial consoles.

The micro:bit sits in its edge connector on the underside of a handheld PCB above a pair of AAA batteries, while on the other side are an OLED display and the usual set of pushbuttons. It’s a particularly simple board as the micro:bit contains all the circuitry required to support its peripherals.

He’s coded the games using the Arduino IDE with a modified version of the Arduboy2 library that allows him to easily port Arduboy games written for Arduino hardware. It’s a work in progress as there are a few more features to incorporate, but the idea of using micro:bits as cartridges is rather special. There is a video of the console in action, which we’ve placed below the break.

Continue reading “Microgamer Is A Micro:Bit Handheld Console”

Chopper And Chopper-Stabilised Amplifiers, What Are They All About Then?

One of my first jobs as a freshly minted graduate engineer involved the maintenance of a set of analogue chart recorders. They were museum pieces by the early 1990s: a motorized roll of graph paper across which a pen would traverse in proportion to the voltage on the input terminals. Inside was a simple servo, with a differential amplifier comparing the feedback via a potentiometer from the mechanism with the amplified input.

The recorders dated from the early 1960s, and internally their electronics were from the germanium transistor era: many Mullard OC-series devices, black-painted glass tubes with a red dot, and, unexpectedly, a large electromagnet connected to the 50 Hz AC supply with a reed switch through its middle, something completely new to an overconfident youngster who thought she knew everything.

What I’d stumbled upon was a chopper amplifier, a slightly ungainly and long superseded solution to the problem of DC amplification from the days before ubiquitous integrated circuit op-amps. We have become so used to DC amplifiers that just work, that we have forgotten that there was a time when such devices were an impossibility. The close matching of properties between devices on the same wafer allowed integrated circuit op-amps to achieve stable DC amplification in a way that the best attempts at the same circuits with discrete transistors had failed, but before they happened some desperate measures were called for. Continue reading “Chopper And Chopper-Stabilised Amplifiers, What Are They All About Then?”

Fail Of The Week: The Little Ultrasonic Knife That Couldn’t

We all know the feeling of an idea that sounded great when it was rattling around in our head, only to disappoint when we actually build the thing. It’s a natural consequence of trying new stuff, and when it happens, we salvage what we can and move on, hopefully in wisdom.

The thing that at least semi-defeated [This Old Tony] was an attempt to build an ultrasonic cutter, and it didn’t go well. Not that any blood was shed in the video below, although there seemed like there would be the way [Old Tony] was handling those X-Acto blades. His basic approach was to harvest the transducer and driver from a cheap ultrasonic cleaner and retask the lot into a tool to vibrate a knife rapidly enough to power it through tough materials with ease.

Spoiler alert: it didn’t work very well. We think the primary issue was using a transducer that was vastly underpowered compared to commercial (and expensive) ultrasonic cutters, but we suspect the horn he machined was probably not optimized either. To be fair, modeling the acoustic performance of something like that isn’t easy, so we can’t expect much. But still, it seems like the cutter could have worked better. Share your thoughts on how to make version 2.0 better in the comments.

The video is longish, but it’s as entertaining as any of [Old Tony]’s videos, and packed full of incidental gems, like the details of cavitation. We enjoyed it, even if the results were suboptimal. If you want to see a [This Old Tony] project that really delivers, check out his beautiful boring head build.

Continue reading “Fail Of The Week: The Little Ultrasonic Knife That Couldn’t”

Can Open-source Hardware Be Like Open-source Software?

Hardware and software are certainly different beasts. Software is really just information, and the storing, modification, duplication, and transmission of information is essentially free. Hardware is expensive, or so we think, because it’s made out of physical stuff which is costly to ship or copy. So when we talk about open-source software (OSS) or open-source hardware (OSHW), we’re talking about different things — OSS is itself the end product, while OSHW is just the information to fabricate the end product, or have it fabricated.

The fabrication step makes OSHW essentially different from OSS, at least for now, but I think there’s something even more fundamentally different between the current state of OSHW and OSS: the pull request and the community. The success or failure of an OSS project depends on the community of people developing it, and for smaller projects that can hinge on the ease of a motivated individual digging in and contributing. This is the main virtue of OSS in my opinion: open-source software is most interesting when people are reading and writing that source.

With pure information, it’s essentially free to copy, modify, and push your changes upstream so that others can benefit. The open hardware world is just finding its feet in this respect, but that’s changing as we speak, and I have great hopes. Costs of fabrication are falling all around, open and useful tools are being actively developed to facilitate interchange of the design information. I think there are lessons that OSHW can learn from the OSS community’s pull-request culture, and that will help push the hardware hacker’s art forward.

What would it take to get you to build someone else’s OSHW project, improve on it, and contribute back? That’s a question worth a thoughtful deep dive.

Continue reading “Can Open-source Hardware Be Like Open-source Software?”

Investigating The World’s Rarest Game Boy

Early last year, a very unique Game Boy Color showed up on Chinese shopping site Taobao. Rather than the rather anemic-looking display of the original GBC, this version was modified with a modern IPS LCD. Even in the pictures shown on the product page, it was clear the display on this unit was far more advanced than anything Nintendo ever packed into a Game Boy. The retro gaming community went wild, and soon the site was overwhelmed with orders. The majority of the sales were canceled by the seller, and it’s believed as few as 75 of these hacked GBCs were actually shipped out.

Thanks to one of his viewers, [Colin] was able to get his hands on one of these extremely rare customized handhelds. Clearly a man after our own heart, his first inclination was to tear the thing apart and see how they built it. While he had a fairly good idea of how they managed this hybrid of modern and classic technology, there were a couple of surprises inside.

The device has a completely stock main board, and as such works and plays like a normal GBC. But upon flipping the main board over, [Colin] found a nest of thin magnet wire connecting the new display controller to individual buttons on the front panel. As he later confirmed when he reassembled the system, this allows the user to adjust the display’s brightness by holding “Select” and using the directional pad.

As for the screen itself, the big surprise was that it’s clearly pulled out of a relatively recent smartphone. The screen is physically much larger than the opening in the GBC’s front panel, but through some software trickery the image is displayed only in the area that’s visible to the player. [Colin] managed to get a hold of a few contacts “in the know” who confirmed to him that both the hardware and software for the display controller were specifically created for this application, and are unlikely to be duplicated by anyone else.

Considering most of the Game Boy hacks we cover are about somebody jamming modern hardware into them, it’s an interesting change of pace to see a group that was so adamant about retaining as much original hardware as possible while still managing to improve the user experience.

[Thanks to Doc Oct for the tip]

Continue reading “Investigating The World’s Rarest Game Boy”

One Week Left For Hackaday Belgrade Proposals

Do you have your tickets for Hackaday Belgrade? Our premiere European conference is on 26 May and tickets are on a rapid trajectory to sell out.

Those of you weighing the idea of presenting a talk, you now have less than one week to get your proposal to us. While we have already accepted several exemplary talks, final decisions won’t be made until after the submission deadline passes on Sunday, March 4th.

Mike Harrison showing off his demo work on the 2016 Hackaday Belgrade badge. If you have stories of the demoscene, consider sending in a talk proposal.

What kind of talks are we looking for? We’d love to have a few talks about the demoscene. The conference badge this year is a full-blown retrocomputer, and we’re working on a BASIC for it. If you can push pixels on a Comodore 64, we’d love to hear you talk about it. We’re also suckers for the lesser known stories of tech history (Mike Harrison’s talk on the Eidophor projector tech all but forgotten to history was a delight).

We’re always interested in creative design; think circuit boards that aren’t square and enclosures that go beyond just putting something in a simple box. And of course we’re forever in search of the rare gems that share a glimpse of the research world, like this computing cluster built to get around limited supercomputer time when calculating quantum effect simulations.

These are great talks presented to an audience hungry to share your excitement. Get those proposals in by the end of this weekend!

Reverse Engineering Opens Up The Samsung Gear VR Controller

We love a bit of reverse engineering here at Hackaday, figuring out how a device works from the way it communicates with the world. This project from [Jim Yang] is a great example of this: he reverse-engineered the Samsung Gear VR controller that accompanies the Gear VR add-on for their phones. By digging into the APK that links the device to the phone, he was able to figure out the details of the Bluetooth connection that the app uses to connect to the device. Specifically, he was able to find the commands that were used to get the device to send data, and was able to read this data to determine the state of the device. He was then able to use this to create his own web app to use this data.

Continue reading “Reverse Engineering Opens Up The Samsung Gear VR Controller”