MagSafe Power Bank From Scrap

Just a few short years ago, it was possible to find scrapped lithium batteries for free, or at least for very cheap. What most people at the time didn’t realize is that a battery with multiple cells might go bad because only one cell is bad, leaving the others ready for salvaging. Now it’s not a secret anymore, but if you can manage to get your hands on some there’s a lot of options for use. [ijsf] took a step further with this hack, taking a few cells from a Panasonic battery and wrangling them into a MagSafe-capable power bank for a Mac.

The real hack wasn’t scavenging batteries, however, it was getting the MagSafe to signal the computer to use power from the battery bank to run the computer only, and not to use any of that energy for charging the computer’s internal batteries. This is achieved by disabling the center MagSafe pin, which is the computer’s communication line to the power adapter. After that, the battery bank could be programmed to behave properly (a feat in itself for lithium batteries) and the power bank was successfully put into operation.

Not only was this hack a great guide for how to repurpose cells from a “dead” battery, it’s also an unparalleled quick reference for any work that might need a MagSafe connector. Of course, if you’re going to work with these chargers, make sure that you’re using one that isn’t a cheap clone.

Under The Hood Of AMD’s Threadripper

Although AMD has been losing market share to Intel over the past decade, they’ve recently started to pick up steam again in the great battle for desktop processor superiority. A large part of this surge comes in the high-end, multi-core processor arena, where it seems like AMD’s threadripper is clearly superior to Intel’s competition. Thanks to overclocking expert [der8auer] we can finally see what’s going on inside of this huge chunk of silicon.

The elephant in the room is the number of dies on this chip. It has a massive footprint to accommodate all four dies, each with eight cores. However, it seems as though two of the cores are deactivated due to a combination of manufacturing processes and thermal issues. This isn’t necessarily a bad thing, either, or a reason not to use this processor if you need to utilize a huge number of cores, though; it seems as though AMD found it could use existing manufacturing techniques to save on the cost of production, while still making a competitive product.

Additionally, a larger die size than required opens the door for potentially activating the two currently disabled chips in the future. This could be the thing that brings AMD back into competition with Intel, although both companies still maintain the horrible practice of crippling their chips’ security from the start.

A Chrome Extension For Being A Jerk

What do you do to someone you want to make suffer, slowly? Specifically, at around 70% speed. To [Stephen], the answer is clear, you hit them where it really hurts: YouTube.

Creatively named “Chrome Engine,” [Stephen]’s diabolical Chrome extension has one purpose: be annoying. Every day, it lowers playback rate by 1% on YouTube. It’s a linear progression: 100% the first day, 99% the second day, 98% the third day, etc. It only stops 30 days later, once it hits its target rate of 70% the original speed. This progression is designed to be slow enough not to be noticed. Its icon is nothing more than the standard Chrome icon as [Stephen] firmly believes in the tactic of hiding in plain sight.

But that’s not all, it’s the minute details that drive the ball home. For instance, rather than using local storage to keep track of playback speed, the Chrome sync storage is used. This ensures that, as long as the extension is installed, playback rate will be synchronized between all of your friend’s(if you can even call them that) devices. It even targets casual YouTube users: [Stephen] has specifically designed their extension so that it won’t drop playback by more than 1% at a time. If the victim goes on vacation, the playback speed won’t drop when they’re away and will resume as soon as they’re back.

The last feature, the one [Stephen] is the proudest of, is that the extension manages to keep the YouTube speed controls working as intended. If the victim tries to play at half speed, their videos will be at half speed … of the slower playback rate set by the extension. And it gets even better! You may not know this if you don’t dally around with playback rates, but the audio tends to stop playing when videos are reduced below 50% of their original speed. Fear not! [Stephen] has accounted for this idiosyncrasy! If the victim selects a speed at or above 0.5x, a minimum cap is added so that the actual playback rate will be equal to or above 0.5x. If they select slower than this, they don’t expect sound anyway, so all bets are off.

Check it out here, may your friends (frenemies?) beware. We’re adding it to our April Fools arsenal, even if it is a bit early.

A Wii U That Is Both Computer And Console.

Legendary sudomod forum user [banjokazooie] has once again demonstrated their prowess in Wii U console modification — this time by transforming it into a powerhouse portable computer!

We loved [banjokazooie]’s RetroPie Wii U mod, and happy to see them back again with this build.  What’s in this thing this time around? Buckle up ’cause it’s a ride: an Intel M5 processor core M on their Compute Stick, 4GBs RAM, a 64GB solid-state drive, a 2K LCD touchscreen, Bluetooth, WiFi, a 128GB SD card slot, two 3.7V 4000 mAh batteries, a Pololu 5V,6A step-down voltage regulator, a Teensy 2.0++ dev board, a battery protection PCB, a USB DAC sound card, stereo amp, a USB hub for everything to plug into, and a TP5100 battery charging board. Check it out!

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KIM-1 To COSMAC Elf Conversion — Sort Of

In the mid-1970s, if you had your own computer, you probably built it. If you had a lot of money and considerable building skill, you could make an Altair 8800 for about $395 — better than the $650 to have it built. However, cheaper alternatives were not far behind.

In 1976, Popular Electronics published plans for a computer called the COSMAC Elf which you could build for under $100, and much less if you had a good junk box. The design was simple enough that you could build it on a piece of perf board or using wire wrap. We featured the online archive of the entire Popular Electronics collection, but hit up page 33 of this PDF if you want to jump right to the article that started it all. The COSMAC Elf is a great little machine built around a 40-pin RCA 1802 processor, and for many was the first computer they owned. I lost my original 1802 computer in a storm and my recent rebuild in another completely different kind of storm. But there is a way to reclaim those glory days without starting from scratch.  I’m going to repurpose another retro-computing recreation; the KIM-1.

I’ll admit it, Rewiring a real KIM-1 to take an 1802 CPU would be difficult and unnecessary and that’s not what this article is about. However, I did have a KIM UNO — [Oscar’s] respin of the classic computer using an Arduino mini pro. Looking at the keyboard, it occurred to me that the Arduino could just as easily simulate an 1802 as it could a 6502. Heck, that’s only two digits different, right?

The result is pretty pleasing. A “real” Elf had 8 toggle switches, but there were several variations that did have keypads, so it isn’t that far off. Most Elf computers had 256 bytes of memory (without an upgrade) but the 1802 UNO (as I’m calling it) has 1K. There’s also a host of other features, including a ROM and a monitor for loading and debugging programs that doesn’t require any space in the emulated 1802.

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Virtual CPU Stays On Script

Some will see it as a great thing, and others as an example of how JavaScript is being abused daily, but [Francis Stokes] decided to design his own CPU architecture and implemented a virtual version of it using JavaScript. The CPU is a 16-bit affair and has a simplified assembly language. The code is on GitHub, but the real value is [Francis’] exposition of the design in the original post.

While discussing the design, [Francis] reveals his first pass at the instruction set, discussed what he found wrong about it, and then reveals the final set composed of real instructions and some macros to handle other common cases.

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The Acorn Archimedes At 30

The trouble with being an incidental witness to the start of something that later becomes world-changing is that at the time you are rarely aware of what you are seeing. Take the Acorn Archimedes, the home computer for which the first ARM processor was developed, and which has just turned 30. If you were a British school pupil in 1987 who found a pair of the new machines alongside the row of BBC Micros in the school computer lab, for sure it was an exciting event, after all these were the machines everyone was talking about. But the possibility that their unique and innovative processor would go on to spawn a line of successors that would eventually power so much of the world three decades later was something that probably never occurred to spotty ’80s teens.

[Computerphile] takes a look at some of the first Archimedes machines in the video below the break. We get a little of the history and a description of the OS, plus a look at an early model still in its box and one of the last of the Archimedes line. Familiar to owners of this era of hardware is the moment when a pile of floppies is leafed through to find one that still works, then we’re shown the defining game of the platform, [David Braben]’s Lander, which became the commercial Zarch, and provided the template for his Virus and Virus 2000 games.

The Trojan Room Coffee Cam Archimedes, on display at the Cambridge University Computing Department.
The Trojan Room Coffee Cam Archimedes, on display at the Cambridge University Computing Department.

We see the RiscOS operating system booting lightning-fast from ROM and still giving a good account of itself 20 years later even on a vintage Philips composite monitor. If you were that kid in 1987, you were in for a shock when you reached university and sat down in front of the early Windows versions, it would be quite a few years before mainstream computers matched your first GUI.

The Archimedes line and its successors continued to be available into the mid 1990s, but faded away along with Acorn through the decade. Even one being used to power the famous Trojan Room Coffee Cam couldn’t save it from extinction. We’re told they can still be found in the broadcast industry, and until fairly recently they powered much of the electronic signage on British railways, but other than that the original source of machines has gone. All is not lost though, because of course we all know about their ARM joint venture which continues to this day. If you would like to experience something close to an Archimedes you can do so with another computer from Cambridge, because RiscOS is available for the Raspberry Pi.

Sit back and enjoy the video, and if you were one of those kids in 1987, be proud that you sampled a little piece of the future before everyone else did.

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