On Cloud Computing And Learning To Say No

April 9, 2024 by 45 Comments

Do you really need that cloud hosting package? If you’re just running a website — no matter whether large or very large — you probably don’t and should settle for basic hosting. This is the point that [Thomas Millar] argues, taking the reader through an example of a big site like Business Insider, and their realistic bandwidth needs.

From a few stories on Business Insider the HTML itself comes down to about 75 kB compressed, so for their approximately 200 million visitors a month they’d churn through 30 TB of bandwidth for the HTML assuming two articles read per visitor.

This comes down to 11 MB/s of HTML, which can be generated dynamically even with slow interpreted languages, or as [Thomas] says would allow for the world’s websites to be hosted on a system featuring single 192 core AMD Zen 5-based server CPU. So what’s the added value here? The reduction in latency and of course increased redundancy from having the site served from 2-3 locations around the globe. Rather than falling in the trap of ‘edge cloud hosting’ and the latency of inter-datacenter calls, databases should be ideally located on the same physical hardware and synchronized between datacenters.

In this scenario [Thomas] also sees no need for Docker, scaling solutions and virtualization, massively cutting down on costs and complexity. For those among us who run large websites (in the cloud or not), do you agree or disagree with this notion? Feel free to touch off in the comments.

In A Twist, Humans Take Jobs From AI

April 9, 2024 by 41 Comments

Back in the 1970s, Rockwell had an ad that proudly proclaimed: “The best electronic brains are still human.” They weren’t wrong. Computers are great and amazing, but — for now — seemingly simple tasks for humans are out of reach for computers. That’s changing, of course, but computers are still not good at tasks that require a little judgment. Suppose you have a website where people can post things for sale, including pictures. Good luck finding a computer that can reliably reject items that appear to be illegal or from a business instead of an individual. Most people could easily do that with a far greater success rate than a computer. Even more so than a reasonable-sized computer.

Earlier this month, we reported on Amazon stepping away from the “just walk out” shopping approach. You know, where you just grab what you want and walk out and they bill your credit card without a checkout line. As part of the shutdown, they revealed that 70% of the transactions required some human intervention which means that a team of 1,000 people were behind the amazing technology.

Humans in the Loop

That’s nothing new. Amazon even has a service called Mechanical Turk that lets you connect with people willing to earn a penny a picture, for example, to identify a picture as pornographic or “not a car” or any other task you really need a human to do. While some workers make up to $6 an hour handling tasks, the average worker makes a mere $2 an hour, according to reports. (See the video below to see how little you can make!) The name comes from an infamous 200-year-old chess-playing “robot.” It played chess as well as a human because it was really a human hiding inside of it.

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Adjustable Lights Help Peer Inside Chips With IR

April 9, 2024 by 3 Comments

If you’re used to working through a microscope, you’ve probably noticed that the angle of the light greatly affects how your workpiece looks. Most of us prefer the relatively flat lighting provided by a ring light, but variable angle side lighting can be useful too, especially when you’re peering inside ICs to make sure the silicon is what it’s supposed to be.

That’s what [Bunnie] is working on these days with his Project IRIS, short for “Infrared in situ,” a non-destructive method for looking inside chip packages. The technique relies on the fact that silicon is transparent to certain wavelengths of light, and that some modern IC packages expose the underside of the silicon die directly to the outside world. Initial tests indicated that the angle of the incident IR light was important to visualizing features on the metal interconnects layered onto the silicon, so [Bunnie] designed a two-axis light source for his microscope. The rig uses curved metal tracks to guide a pair of IR light sources through an arc centered on the focal point of the microscope stage. The angle of each light source relative to the stage can be controlled independently, while the whole thing can swivel around the optical axis of the microscope to control the radial angle of the lighting.

The mechanism [Bunnie] designed to accomplish all this is pretty complex. Zenith angle is controlled by a lead screw driving a connecting rod to the lights on their guide tracks, while the azimuth of the lights is controlled by a separate motor and pulley driving a custom-built coaxial bearing. The whole optical assembly is mounted on a Jubilee motion platform for XYZ control. The brief videos below show the lights being put through their paces, along with how changing the angle of the light affects the view inside a chip.

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Bye Bye Green Screen, Hello Monochromatic Screen

April 9, 2024 by 60 Comments

It’s not uncommon in 2024 to have some form of green background cloth for easy background effects when in a Zoom call or similar. This is a technology TV and film studios have used for decades, and it’s responsible for many of the visual effects we see every day on our screens. But it’s not perfect — its use precludes wearing anything green, and it’s very bad at anything transparent.

The 1960s Disney film makers seemingly had no problem with this as anyone who has seen Mary Poppins will tell you, so how did they manage to overlay actors with diaphanous accessories over animation? The answer lies in an innovative process which has largely faded from view, and [Corridor Crew] have rebuilt it.

Green screens, or chroma key, to give the effect its real name, relies on the background using a colour not present in the main subject of the shot. This can then be detected electronically or in software, and a switch made between shot and inserted background. It’s good at picking out clean edges between green background and subject, but poor at transparency such as a veil or a bottle of water. The Disney effect instead used a background illuminated with monochromatic sodium light behind the subject illuminated with white light, allowing both a background and foreground image to be filmed using two cameras and a dichroic beam splitter. The background image with its black silhouette of the subject could then be used as a photographic stencil when overlaying a background image.

Sadly even Disney found it very difficult to make more than a few of the dichroic prisms, so the much cheaper green screen won the day. But in the video below the break they manage to replicate it with a standard beam splitter and a pair of filters, successfully filming a colourful clown wearing a veil, and one of them waving their hair around while drinking a bottle of water. It may not find its way back into blockbuster films just yet, but it’s definitely impressive to see in action.

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PumpkinOS

PumpkinOS: A Modern Reimplementation Of PalmOS For Today’s Platforms

April 8, 2024 by 25 Comments

In a world where the personal digital assistant (PDA) has become yet another retro computing system, it’s always nice when experiencing the software for such platforms can be done in a way that does not involve hunting down original hardware of questionable functionality. Here PumpkinOS is a PalmOS-compatible project by [migueletto] which runs as a regular application on modern systems and allows for  original PalmOS applications for the Motorola 68k to run on x86 and ARM host systems.

On start-up the Launcher shows up first, just like with PalmOS, from which the four standard PalmOS applications (AddressBook, MemoPad, ToDoList and DateBook) can be launched. Due to endianness issues (m68k being Big Endian), files created by these applications cannot be shared between PumpkinOS and PalmOS, and as noted on the GitHub page, it’s still a far from finished project. That said, it appears to be able to run quite a few original PalmOS applications from sites like PalmDB, and compatibility should get better over time.

The author maintains a development blog as well, for those who are interested in the more in-depth details of this project.

Query Your C Code

April 8, 2024 by 17 Comments

If you’ve ever worked on a large project — your own or a group effort — you know it can be difficult to find exactly where you want to be in the source code. Sure, you can use ctags and most other editors have some way of searching for things. But ClangQL from [AmrDeveloper] lets you treat your code base like a database.

Honestly, we’ve often thought about writing something that parses C code and stuffs it into a SQL database. This tool leverages the CLang parser and lets you write queries like:

SELECT * FROM functions

That may not seem like the best example, but how about:

SELECT COUNT(name) FROM functions WHERE return_type="int"

That’s a bit more interesting. The functions table provides each function’s name, signature, a count of arguments, a return type, and a flag to indicate methods. We hope the system will grow to let you query on other things, too, like variables, templates, preprocessor defines, and data types. The tool can handle C or C++ and could probably work with other CLang front ends with a little work.

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A Brief History Of Keyboard Encoding

April 8, 2024 by 17 Comments
Photoelectric encoder keyboard configured as ASCII
Photoelectric encoder keyboard configured as ASCII

While typing away on our DIN, PS/2, USB or Bluetooth keyboards one of the questions which we rarely concern ourselves with is that of how the keyboard registers which keys we’re pressing. One exception here is when the keyboard can only register a limited number of simultaneous keypresses (rollover). Even though most keyboards today use a matrix which connects the keys, there are many configuration choices even here, which much like other keyboard configurations come with their own advantages and disadvantages. As a good primer we can look at this article by [Daniel Beardsmore] as he takes us through both historical and current-day keyboards.

Especially before  it was realistic to just put an entire microcontroller with a look-up table into every keyboard, more inventive approaches were required to not only register keypresses, but also encode them for the host computer. The photoelectric approach of the 1960s was one such encoding method, before diode matrices became popular, along with more exotic encoding switches that contained their code already hard-wired on their multitude of pins. One inevitable limitation with these was that of a lack of multi-key support, leading to the development of matrix scan technology around 1970.

Matrix scanning keyboards allow for multiple key presses at the same time, tackle debouncing of keys and were at the forefront of what gives us the ubiquitous and generally boringly reliable keyboards which we use today.