Retrotechtacular: Crash Testing Truck Attenuators, For Science

October 27, 2023 by Dan Maloney 19 Comments

There are those among us who might bristle at something from the early 1980s qualifying for “Retrotechtacular” coverage, but it’s been more than 40 years since the California Department of Transportation’s truck-mounted attenuators crash testing efforts, so we guess it is what it is.

If you’re worried that you have no idea what a “truck-mounted attenuator” might be, relax — you’ve probably seen these devices attached to the backs of trucks in highway work zones. They generally look like large boxes attached to frames at the rear of the truck which are intended to soften the blow should a car somehow not see the giant orange truck covered with flashing lights and drive into the rear of it at highway speeds. Truck-mounted attenuators are common today, but back in 1982 when this film was produced, the idea was still novel enough to justify crash-testing potential designs.

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Simple Badge Is Simple, But It’s Yours

October 26, 2023 by Al Williams 8 Comments

Making conference badges, official or unofficial, has become an art form. It can get pretty serious. #badgelife.

But DEFCON-goers aren’t the only people making fancy personalized nametags. Hams often had callsign badges going back as far as I can remember. Most were made of engraved plastic, but, at some point, it became common to put something like a flashing LED on the top of the engraved antenna tower or maybe something blinking Morse code.

Going back to that simpler time, I wanted to see if I could make my own badge out of easily accessible modules. How easy can it be? Let’s find out. Along the way, we’ll talk about multicore programming, critical sections, namespaces, and jamming images into C++ code. I’ll also show you how to hijack the C preprocessor to create a little scripting language to make the badge easier to configure.

Bottom Line Up Front

The photo shows the Pico badge. It has an RP2040 CPU but not a proper Raspberry Pi Pico. The Waveshare RP2040-Plus clone has a battery connector and charger. It also has a reset button, and this one has 16 MB of flash, but you don’t need that much. The LCD is also a Waveshare product. (This just happened to work out. I bought all of this stuff, and I don’t even know anyone at Waveshare.) The only other thing you need is a USB C cable and a battery with an MX 1.25 connector on it with the correct polarity. Hardware done! Time for software.

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Illustrated Kristina with an IBM Model M keyboard floating between her hands.

Keebin’ With Kristina: The One With The Foot Keyboard

October 25, 2023 by Kristina Panos 12 Comments

[crispernaki]’s opening comments to this VCR head scroll wheel project lament that overall technical details aren’t “complex, ground-breaking, or even exciting.” Since when does that matter? The point is that not only did the thing finally, eventually get built, it gets daily use and it sparks joy in its owner.

This feel-good story is one of procrastination, laziness, and one aha! moment, and it’s roughly twelve years in the making. Inspired by an Instructable from long ago, [crispernaki] ran straight to the thrift store to get a VCR and take it apart.

The original plan was to just reuse the VCR head’s PCB and hide it in an enclosure, and then figure out way to block and unblock the path between an IR emitter/receiver pair. After many disemboweled mice and fruitless attempt, the project was once again shelved.

But then, [crispernaki] remembered the magnetic rotary encoder demo board that was just sitting around, along with various microcontrollers and Altoids tins. And it all quickly came together with a Teensy 2.0 and some bits and bobs, including a magnet glued on the shaft of the VCR head. A chip on the demo board does all the heavy lifting, and of course, the Teensy does the work of emulating an HID.

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Linux Fu: Customizing Printf

October 24, 2023 by Al Williams 13 Comments

When it comes to programming in C and, sometimes, C++, the printf function is a jack-of-all-trades. It does a nice job of quickly writing output, but it can also do surprisingly intricate formatting. For debugging, it is a quick way to dump some data. But what if you have data that printf can’t format? Sure, you can just write a function to pick things apart into things printf knows about. But if you are using the GNU C library, you can also extend printf to use custom specifications. It isn’t that hard, and it makes using custom data types easier.

An Example

Suppose you are writing a program that studies coin flips. Even numbers are considered tails, and odd numbers are heads. Of course, you could just print out the number or even mask off the least significant bit and print that. But what fun is that?

Here’s a very simple example of using our new printf specifier “%H”:

printf("%H %H %H %H\n",1,2,3,4);
printf("%1H %1H\n",0,1);

When you have a width specification of 1 (like you do in the second line) the output will be H or T. If you have anything else, the output will be HEADS or TAILS.

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Retrotechtacular: The $175,000 Laser Printer

October 23, 2023 by Al Williams 38 Comments

Laser printers today are cheap and readily available. But in 1976, they were the height of printing technology. The IBM 3800 was the $175,000 printer to have in that year. (Video, embedded below.) But you couldn’t have one on your desktop. Even if you could afford it, the thing is the size of a car, and we don’t even want to guess what it weighs. The printer took tractor-fed continuous form paper and could do 167 pages a minute at about 150 dots per inch (actually 180 x 144). For the record, that was as much as 1.7 miles of paper an hour!

In those days, people who would use this printer traditionally had massive banks of noisy impact printers. We imagine this device saved many data processing person’s hearing. Compared to a modern laser printer, though, it needed a lot of maintenance. For example, the initial models needed a xenon flash lamp replaced every month, although later models could go years on one bulb. Looking at some of the hardware in the video, it was probably made closer to the end of life for these printers which were made through 1999.

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Hackaday Links: October 22, 2023

October 22, 2023 by Dan Maloney 9 Comments

The second of three major solar eclipses in a mere six-year period swept across the United States last week. We managed to catch the first one back in 2017, and still have plans for the next one in April of 2024. But we gave this one a miss, mainly because it was “just” an annular eclipse, promising a less spectacular presentation than a total eclipse.

Looks like we were wrong about that, at least judging by photographs of last week’s “Ring of Fire” eclipse. NASA managed to catch a shot of the Moon’s shadow over the middle of the US from the Deep Space Climate Observer at Lagrange Point 1. The image, which shows both the compact central umbra of the shadow and the much larger penumbra, which covers almost the entire continent, is equal parts fascinating and terrifying. Ground-based photographers were very much in the action too, turning in some lovely shots of the eclipse. We particularly like this “one-in-a-million” shot of a jet airliner photobombing the developing eclipse. Shots like these make us feel like it was a mistake to skip the 10-hour drive to the path of annularity.

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The Eternal Dilemma

October 21, 2023 by Elliot Williams 3 Comments

It’s two weeks until Supercon! We can almost smell the solder from here. If you’re coming, and especially if it’s your first time, you’re soon to be faced with the eternal dilemma of hacker cons, only at Supercon it’s maybe a trilemma or even a quadralemma: hang out with folks, work on the badge, go to talks, or show off all the cool stuff you’ve been working on the past year?

Why not all four? That’s exactly why we start off with a chill-out day on Friday, when we don’t have much formally planned. Sure, there’s a party Friday night, and maybe a badge talk or some workshops, but honestly you’ll have most of the day free. Ease into it. Have a look at the badge and start brainstorming. Meet some new people and start up a team. Or just bathe in the tremendous geekery of it all. This is also a great time to show off a small project that you brought along. Having the widget that you poured brain, sweat, and tears into sitting on the table next to you is the perfect hacker icebreaker.

On Saturday and Sunday, there will definitely be talks that you’ll want to attend, so scope that out ahead of time and plan those in. But don’t feel like you have to go to all of them, either. Most of the talks will be online, either right away or eventually, so you won’t miss out forever. But since our speakers are putting their own work out there, if you’re interested in the subject, having questions or insight about their talk is a surefire way to strike up a good conversation later on, and that’s something you can’t do online. So plan in a few talks, too.

You’ll find that the time flies by, but don’t feel like you have to do it all either. Ask others what the coolest thing they’ve seen is. Sample as much as you can, but it’s not Pokemon – you can’t catch it all.

See you in two weeks!

(PS: The art is recycled from a Supercon long, long ago. I thought it was too nice to never see it again.)