The purpose of the <keygen/> element was to allow a web browser to generate a private/public keypair upon submitting a form, in a way that allowed a web browser to be enrolled in a new client certificate.

source: L

The bottom line is, as we’ll demonstrate in the next few screenshots, this laptop isn’t just a MIPS laptop: it’s three apparently completely independent RISC systems with their own memory, flash and operating system on an internal Ethernet network. All those NIC and switch chips are the internal communication interfaces from the Au1550 to the IXP425 and the AR2316A, but using the IDE bus lines instead of actual twisted pair. That’s not what I was expecting to find in a Sun Ray!

source: HN

Two boxers. No flicker? How is this possible? The MMC2 Mapper chip: Explained

How to draw too many sprites by making one a background, then how to smoothly animate it by side scrolling.

Determining the airspeed and altitude of a fighter plane is harder than you’d expect. At slower speeds, pressure measurements can give the altitude, air speed, and other “air data”. But as planes approach the speed of sound, complicated equations are needed to accurately compute these values. The Bendix Central Air Data Computer (CADC) solved this problem for military planes such as the F-101 and the F-111 fighters, and the B-58 bomber. This electromechanical marvel was crammed full of 1955 technology: gears, cams, synchros, and magnetic amplifiers. In this blog post I look inside the CADC, describe the calculations it performed, and explain how it performed these calculations mechanically.

The use of floppies is hardly some previously unknown fact; for starters, Tumlin explicitly told KQED that his agency has to retain staff with skills honed to what amounts to the programming equivalent of Ancient Babylonian. But Twitter users on Thursday expressed surprise that a city known as a global tech capital would be so reliant on a storage format that lacks the capacity to store a single hi-resolution photograph.

Previously: https://www.sfexaminer.com/news/tech-in-the-tunnels-muni-train-control-system-gets-biggest-upgrade-since-the-90s/article_9e96254c-f8b3-5ee8-b21a-227b3cd6eb2c.html

Relay racks extend down a cramped hallway nearly 15 feet deep, where dozens of 4-inch copper filaments clatter up and down like teeth. The speedy “click, clack” sound signifies a smooth running Muni light rail automatic control system, which commands the J-Church, K-Ingleside, L-Taraval, M-Ocean View, N-Judah and T-Third Street trains through the tunnels. The clapping beat signifies the proper alignment of the railway’s 83 axle (controls) and numerous other track switches.

source: jwz

Presenting the list I mentioned earlier in which I highlight a number of worthwhile science-fiction films (also some TV productions) that aren’t the usual Hollywood fare. I’ve spent the past few years watching many of these while searching for more. This isn’t a definitive collection, and it isn’t filled with favourites; I’ve deliberately omitted a number of popular films that would count as such. It’s more a map of my generic tastes, and an answer to a question that isn’t always spoken aloud in discussions I’ve had about SF films but which remains implicit: “Okay, if you dislike all this stuff then what do you like?” I tend to like marginal things, hybrids, edge cases, the tangential, the unusual and the experimental.

Just the stills make for interesting browsing.

source: Dfly

I watched 《loki》 some time ago, and I really liked the digital styling setting that combines retro and future in the show, so I rendered a detailed enhanced version of a multifunctional computer.

Or: https://www.yankodesign.com/2021/12/04/this-retro-futuristic-computer-from-the-loki-series-is-worth-every-marvel-fans-appreciation/

source: jwz

I’ll cut to the chase; through a combination of unlikely discoveries, crazy hacks and the 90s BBS warez scene I’ve been able to port Lotus 1-2-3 natively to Linux – an operating system that literally didn’t exist when 1-2-3 was released!

source: L

I spent the last two months (roughly ~150 hours) porting Zelda Classic to run in a web browser.

I hope my efforts result in Zelda Classic reaching a larger audience. It’s been challenging work, far outside my comfort zone of web development, and I’ve learned a lot about WebAssembly, CMake and multithreading. Along the way, I discovered bugs across multiple projects and did due diligence in fixing (or just reporting) them when I could, and even proposed a change to the HTML spec.

Weird how there’s bugs everywhere one looks.

The basic idea was to send a radio signal to the spacecraft and determine how long it takes to return. Since the signal traveled at the speed of light, the time delay gives the distance. The main problem is that due to the extreme distance to the spacecraft, a radar-like return pulse would be too weak. The ranging system solved this in two ways. First, a complex transponder on the spacecraft sent back an amplified signal. Second, instead of sending a pulse, the system transmitted a long pseudorandom bit sequence. By correlating this sequence over multiple seconds, a weak signal could be extracted from the noise.

In this blog post I explain this surprisingly-complex ranging system. Generating and correlating pseudorandom sequences was difficult with the transistor circuitry of the 1960s. The ranging codes had to be integrated with Apollo’s “Unified S-Band” communication system, which used high-frequency microwave signals. Onboard the spacecraft, a special frequency-multiplying transponder supported Doppler speed measurements. Finally, communicating with the spacecraft required a complex network of ground stations spanning the globe.

And: https://righto.com/apollo/ranging-xor.html

http://www.righto.com/2022/05/talking-with-moon-inside-apollos.html

Chaining was a common technique when your program got too large to fit into memory all at once, so you broke it into multiple programs that each handed off control to each other.

As the author added features, he kept hitting the Apple ][‘s 48KB RAM limit and was forced to delete all the comments from the code, and when that wasn’t enough, he resorted to shortening all the important variable names to one character.

Recently, I took a look at Nintendo’s MMC line of mappers, and some other boards. All boards for the NES’ western releases had to be manufactured by Nintendo, and so they generally met certain standards set by Nintendo. But these rules were enforced by technology, not by law. And the company that had previously killed the American game industry decided to break those rules. Madness? No. This… is Tengen.

Lots of custom cartridges here.

Some additional info: https://hackmii.com/2010/01/the-weird-and-wonderful-cic/

source: HN

Known as right angle with downwards zigzag arrow, angle with down zig-zag arrow, \rangledownzigzagarrow, and &angzarr;, no one knows what ⍼ is meant to represent or where it originated from. Section 22.7 Technical Symbols from the Unicode Standard on the Miscellaneous Technical block doesn’t say anything about it.

source: L

Making hard drives out of pings, tetris, and covid tests.

Video: https://www.youtube.com/watch?v=JcJSW7Rprio

A ton of hacking later, and I do now have a usable driver for dosemu that supports arbitrary resolutions, just look at all those columns!

source: HN

The goal for this project is to design, 3D-print and assemble the enclosures for several small desktop computers.

source: jwz

I always loved the visual aesthetic of dithering but never knew how it’s done. So I did some research. This article may contain traces of nostalgia and none of Lena.

A reply or follow up: https://www.makeworld.space/2021/02/dithering.html

source: HN

1963 Chrysler Turbine: Ultimate Edition. It’s the amazing car Jay’s lusted after since he was 14 years old, and today’s episode is packed with all kinds of amazing footage! We’ve got a book review, a road test, and Chrysler’s original promotional video.

Part of Computer Arithmetic. http://www.quadibloc.com/comp/cp02.htm

And How does a computer work? http://www.quadibloc.com/comp/cpint.htm

source: trivium

So this nutty little experiment connects a PC, or an IBM PC to be exact, directly onto a record player through an amplifier. There is a small ROM boot loader that operates the built-in “cassette interface” of the PC (that was hardly ever used), invoked by the BIOS if all the other boot options fail, i.e. floppy disk and the hard drive. The turntable spins an analog recording of a small bootable read-only RAM drive, which is 64K in size. This contains a FreeDOS kernel, modified by me to cram it into the memory constraint, a micro variant of COMMAND.COM and a patched version of INTERLNK, that allows file transfer through a printer cable, modified to be runnable on FreeDOS. The bootloader reads the disk image from the audio recording through the cassette modem, loads it to memory and boots the system on it. Simple huh?

source: L