Author: Al Williams

4513 Articles

The 10,000 Pixel Per Inch Display Is Now Possible

October 28, 2020 by 54 Comments

A good smartphone now will have about 500 pixels per inch (PPI) on its screen. Even the best phones we could find clock in at just over 800 PPI. But Stanford researchers have a way to make displays with more than 10,000 pixels per inch using technology borrowed from solar panel research.

Of course, that might be overkill on a six-inch phone screen, but for larger displays and close up displays like those used for virtual reality, it could be a game-changer. Your brain is good at editing it out, but in a typical VR headset, you can easily see the pixels from the display even at the highest PPI resolutions available. Worse, you can see the gaps between pixels which give a screen door-like effect. But with a density of 10,000 PPI it would be very difficult to see individual pixels, assuming you can drive that many dots.

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Inside The Top Secret Doughnut: A Visit To GCHQ

October 26, 2020 by 31 Comments

There’s an old joke that the world’s greatest secret agent was Beethoven. Didn’t know Beethoven was a secret agent? That’s why he was the greatest one! While most people have some idea about the CIA, MI6, and the GRU, agencies like the NRO and GCHQ keep a much lower profile. GCHQ (Government Communications Headquarters) is the United Kingdom’s electronic listening center housed in a 180 meter round doughnut. From there they listen to… well… everything. They are also responsible for codebreaking and can trace their origin back to Bletchley Park as well as back to the Great War. So what’s inside the Doughnut? National Geographic managed to get a tour of GCHQ and if you have any interest in spies, radios, cybersecurity, or codebreaking, it is worth having a look at it.

Of course, only about half of the GCHQ’s employees work in the Doughnut. Others are scattered about the UK and — probably — some in other parts of the world, too. According to the article, GCHQ had a hand in foiling 19 terrorist attacks, arresting at least two sex offenders, and prevented about £1.5 billion of tax evasion.

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Do Your Part To Stop The Robot Uprising

October 21, 2020 by 11 Comments

One of the pleasures of consuming old science fiction movies and novels is that they capture the mood of the time in which they are written. Captain Kirk was a 1960s guy and Picard was a 1990s guy, after all. Cold war science fiction often dealt with invasion. In the 1960s and 70s, you were afraid of losing your job to a computer, so science fiction often had morality tales of robots running amok, reminding us what a bad idea it was to give robots too much power. As it turns out, robots might be dangerous, but not for the reasons we thought. The robots won’t turn on us by themselves. But they could be hacked. To that end, there’s a growing interest in robot cybersecurity and Alias Robotics is releasing Alurity, a toolbox for robot cybersecurity.

Currently, the toolbox is available for Linux and MacOS with some support for Windows. It targets 25 base robots including the usual suspects. There’s a white paper from when the product entered testing available if you want more technical details.

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Correlated Electron Memory… Coming Soon?

October 21, 2020 by 26 Comments

We often see press releases and announcements about the next big technology in batteries, memory, displays, capacitors, or any of a number of other things. Usually we are suspicious since we typically don’t see any of this new technology in the marketplace over any reasonable timescale. So when we read about correlated-electron memory Cerfe Labs, we had to wonder if it would be more of the same. IOur suspicions may be justified of course, but it is telling that the company is a spin-off from ARM, so that gives them some real-world credibility.

Correlated-electron RAM or CeRAM is the usual press release material. Nonvolatile, smaller than SRAM, and fast. It sounds as though it could replace the SRAM in PC caches, for example, and take up less die space on the CPU chip. The principle is a bit odd. When electrons are forced together in certain materials, the properties of the material can change. This Mott transition (named after the inventor [Neville Mott]) can take carbon-doped nickel oxide and switch it from its natural electrical insulating state to a conducting state and back again.

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Arduino And Wire Detects Metal

October 21, 2020 by 7 Comments

Our old math teacher famously said, “You have to take what you know and use it find what you don’t know.” The same holds true for a lot of microcontroller designs including [rgco’s] clever metal detector that uses very little other than an Arduino. The principle of operation is simple. An Arduino can measure time, a coil and a resistor will create a delay proportional to the circuit values, and metal around the coil will change the coil’s inductance. As the inductance changes, so does the delay and, thus, the Arduino can sense metal, as you can see in the video below.

The simple principle is also simple in practice. Besides the Arduino and the coil, there’s a single resistor. You want a small coil since larger coils won’t detect smaller objects. If you don’t want to wind your own coil, [rgco] suggests using a roll of hookup wire as long as the resistance is under 10 ohms.

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Learn IC Decapping

October 21, 2020 by 15 Comments

Decapsulating ICs used to be an exotic technique. (I should know, I did that professionally for one of the big IC vendors back in the 1980s.) These days, more and more people are learning to take apart ICs for a variety of reasons. If you are interested in doing it yourself, [Juan Carlos Jimenez] has a post you should read about using acid to remove epoxy from ICs.

[Juan Carlos] used several different techniques with varying degrees of success. Keep in mind, that using nitric acid is generally pretty nasty. You need safety equipment and be sure to plan for bad things to happen. Have eyewash ready because once you splash acid in your eye, it is too late to get that together.

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Thinking About Creating A Raspberry Pi Replacement?

October 20, 2020 by 66 Comments

If you’ve ever wanted to try your hand at creating a Raspberry Pi-like board for yourself, you should check out [Jay Carlson’s] review of 10 different Linux-capable SoCs. Back in the 1960s, a computer was multiple refrigerator-sized boxes with thousands of interconnections and building one from scratch was only a dream for most people. Then ICs came and put all the most important parts in a little relatively inexpensive IC package and homebrew computing became much more accessible. Systems on Chip (SoC) has carried that even further, making it easier than ever to create entire systems, like the Pi and its many competitors.

Only a few years ago, making an SoC was still a big project because the vendors often didn’t want to release documentation to the public. In addition, most of the parts use ball grid array (BGA) packaging. BGA parts can be hard to work with, and require a multilayer PC board. Sure, you can’t plug these into a typical solderless breadboard. But working with these relatively large BGAs isn’t that hard and multilayer boards are now comparatively cheap. [Jay] reports that he got cheap PCBs and used a hot plate to build each board, and has some sage advice on how to do it.

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