Simple ATX Bench Power Supply Adds Variable Output

December 1, 2022 by 24 Comments

A benchtop power supply is a key thing to have for any aspiring electronics hacker. While you can always buy one, plenty of us have old computer PSUs lying around that could do a fine job themselves. [Frugha] decided to whip up a neat 3D-printed design for converting any ATX PSU into a usable bench unit.

The design features banana plugs outputting +12V, -12V, +5V, and +3.3V, with all outputs appropriately fused for safety. There’s also a fused stepdown converter used to supply variable voltages as needed. Its original trimpot was replaced with a multi-turn pot for ease of control. To make everything work, a load resistor on the 5V circuit makes the power supply think it’s hooked up to a motherboard. It’s all wrapped up in a neat slant-sided 3D-printed case that fits onto the ATX power supply itself.

The result is a neat and tidy power supply built out of readily-available components. We particularly like the addition of the stepdown converter – most ATX-based projects don’t offer variable output, which can nonetheless come in handy.

We’ve seen some other great builds along these lines before, too. If you’ve been cooking up your own homebrew power supply, don’t hesitate to share it on the tipsline! 

Rescue That Dead Xbox With An External PSU

December 1, 2022 by 13 Comments

There is nothing worse than that sinking feeling as a computer or other device fails just after its warranty has expired. [Robotanv] had it with his Xbox Series S whose power supply failed, and was faced with either an online sourced PSU of uncertain provenance, or a hefty bill from Microsoft for a repair. He chose to do neither, opening up his console and replacing the broken PSU with a generic external model. See the video below the break.

The Xbox appears surprisingly well designed as a modular unit, so accessing and unplugging its PSU was quite easy. To his surprise he found that the connections were simply two wires, positive and negative lines for 12 V. The solution was to find a suitably beefy 12 V supply and wire it up, before continuing gaming.

Beyond that simple description lies a bit more. The original was a 160 W unit so he’s taken a gamble with a 120 W external brick. He’s monitoring its temperature carefully to make sure, but with his gaming it has not been a problem. Then there’s the board wiring, which he appears to have soldered to pads on the PCB. We might have tried to find something that fit the original spade connectors instead, but yet again it hasn’t caused him any problems. We’d be curious to see what has failed in the original PSU. Meanwhile we’re glad to see this Xbox ride again, it’s more than can be said for one belonging to a Hackaday colleague.

Continue reading “Rescue That Dead Xbox With An External PSU” →

Car Batteries: More Than Just Wet Lead

December 1, 2022 by 47 Comments

Working on car electrical systems used to be easy. The battery simply provided power for the car’s starter motor when starting or to run the small number of accessories when the engine wasn’t running. The rest of the time, the alternator charged the battery and provided power for the rest of the vehicle and the ignition system. While very early cars didn’t have batteries, and some old cars had 6 V positive ground systems, most of us have lived our entire lives where car batteries come in several sizes (controlled by Battery Council International) and cars have a 12 V, negative ground system.

Times have changed. Cars don’t have distributors anymore, they have computers. They also have lots of gadgets from GPS to backup cameras and cellphone chargers. Batteries have had to get beefier and the modern trend is to also require less maintenance So, today, you’ll find that there isn’t just one kind of car battery. But how do these other batteries work and what was wrong with the good old lead acid wet cell?

For the purposes of this post, I’m not talking about electric car batteries which is a whole different topic — and most of them have a regular car battery, too. Continue reading “Car Batteries: More Than Just Wet Lead” →

Taking (Good) Pictures Of PCBs

December 1, 2022 by 18 Comments

Snapping pictures is not technically difficult with modern technology, but taking good photographs is another matter. There are a number of things that a photographer needs to account for in order to get the best possible results, and if the subject matter isn’t particularly photogenic to start with it makes the task just a little more difficult. As anyone who’s posted something for sale online can attest, taking pictures of everyday objects can present its own challenges even to seasoned photographers. [Martijn Braam] has a few tricks up his sleeve for pictures like this in his efforts to photograph various circuit boards.

[Martijn] has been updating the images on Hackerboards, an online image reference for single-board computers and other PCBs, and he demands quality in his uploads. To get good pictures of the PCBs, he starts with ample lighting in the form of two wirelessly-controlled flashes in softboxes. He’s also using a high quality macro lens with low distortion, but the real work goes into making sure the image is sharp and the PCBs have well-defined edges. He’s using a Python script to take two pictures with his camera, and some automation in ImageMagic to composite the two images together.

While we’re not all taking pictures of PCBs, it’s a great way of demonstrating the ways that a workflow can be automated in surprising ways, not to mention the proper ways of lighting a photography subject. There are some other excellent ways of lighting subjects that we’ve seen, too, including using broken LCD monitors, or you can take some of these principles to your workspace with this arch lighting system.

Ask Hackaday: When It Comes To Processors, How Far Back Can You Go?

December 1, 2022 by 89 Comments

When it was recently announced that the Linux kernel might drop support for the Intel 486 line of chips, we took a look at the state of the 486 world. You can’t buy them from Intel anymore, but you can buy clones, which are apparently still used in embedded devices. But that made us think: if you can’t buy a genuine 486, what other old CPUs are still in production, and which is the oldest?

Defining A Few Rules

An Intel 4004 microprocessor in ceramic packaging
The daddy of them all, 1972’s Intel 4004 went out of production in 1981. Thomas Nguyen, CC BY-SA 4.0

There are a few obvious contenders that immediately come to mind, for example both the 6502 from 1975 and the Z80 from 1976 are still readily available. Some other old silicon survives in the form of cores incorporated into other chips, for example the venerable Intel 8051 microcontroller may have shuffled off this mortal coil as a 40-pin DIP years ago, but is happily housekeeping the activities of many far more modern devices today. Still further there’s the fascinating world of specialist obsolete parts manufacturing in which a production run of unobtainable silicon can be created specially for an extremely well-heeled customer. Should Uncle Sam ever need a crate of the Intel 8080 from 1974 for example, Rochester Electronics can oblige.

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TEGA: Typescript Embedded Game Boy (Macro) Assembler

December 1, 2022 by 2 Comments

[Francis Stokes] has a real love for the original Game Boy, suggesting that owning this machine pushed him along a certain path that many of us would recognize. Developing Game Boy games isn’t particularly difficult from a hardware point of view, as you can easily buy special cartridges that have an SD card slot, allowing custom code. [Francis] had the idea of easy software development by producing a typescript hardware abstraction library, TEGA (or TypeScript Embedded Game Boy Macro Assembler). This provides a safe environment in which to play with the code, which can then be run inside an emulator such as BGB, before being deployed onto actual hardware.

The video embedded below — which we warn you now is a long one — goes into extensive justification and technical explanation of how [Francis] leverages typescript to create lots of nice features to produce safe code, whilst handling many of the Game Boy’s architectural restrictions, as well as the weirdness of the Sharp SM83 processor that powers it. We particularly liked the built-in support for on-the-fly asset compression, since every byte matters in the meager 32 Kb system, it’s nice not to have to think about it all the time! After discussing TEGA, the Game Boy hardware, the ins and outs of a demo game Block Jump, and then how to debug with BGB, we’re pretty confident many of you will be in a strong position to bust out a Game Boy application in the future!

As an aside, we did also stumble upon a new hardware guide provided by Finnish programmer and Game Boy superfan [Joonas Javanainen] which will help frame some of the topics [Francis] was talking about.

You may recall a little while back, the same author targeted the RISC-V using code written in typescript. After all, when you’re comfortable with a tool, you can shape it to do practically anything.

Continue reading “TEGA: Typescript Embedded Game Boy (Macro) Assembler” →

A Cheap 3D Printer Control Panel As A General Purpose Interface

December 1, 2022 by 15 Comments

Browsing the usual websites for Chinese electronics, there are a plethora of electronic modules for almost every conceivable task. Some are made for the hobbyist or experimenter market, but many of them are modules originally designed for a particular product which can provide useful functionality elsewhere. One such module, a generic control panel for 3D printers, has caught the attention of [Bjonnh]. It contains an OLED display, a rotary encoder, and a few other goodies, and he set out to make use of it as a generic human interface board.

To be reverse engineered were a pair of 5-pin connectors, onto which is connected the rotary encoder and display, a push-button, a set of addressable LEDs for backlighting, a buzzer, and an SD card slot. Each function has been carefully unpicked, with example Arduino code provided. Usefully the board comes with on-board 5 V level shifting.

While we all like to build everything from scratch, if there’s such an assembly commonly available it makes sense to use it, especially if it’s cheap. We’re guessing this one will make its way into quite a few projects, and that can only be a good thing.