No More Floppy Drives For This Agilent Scope

May 10, 2020 by 28 Comments

When [kiwih] picked up an Agilent 54621A scope, he was amused that it had a floppy disk. At one time, it was high-tech to use a disk to transfer scope data to your computer. Today, not so much. However, on the back was a serial port. Surely it was possible to read data from there. It is, and what results is a nice walkthrough of finding the port’s info and interfacing with it using Python.

Normally, you’d use the included BenchLinkXL software to grab data from the port, but that software is so old it would not run under Windows 10 or Wine. Searching didn’t turn up much on the serial port, but it did locate a manual for a similar Agilent scope. That manual wasn’t too helpful since it assumed you were connecting via a LAN or USB. However, it did make reference to an older model that was also similar and that was the key to finding a manual that did explain the serial port protocol.

The command set looks suspiciously like SCPI — Standard Commands for Programmable Instruments — which is a layer on top of the GPIB protocol. Many scopes speak that language, so that’s not surprising. That also means if you are in the mood to communicate with an SCPI scope, you might find the code useful, even if you don’t use a serial port or have this exact Agilent model.

SCPI has a lot of uses. For example, try talking to your scope. The cheap Rigol and similar scopes usually have SCPI and you can control and read them using the same kind of techniques.

512 Bytes Ought To Be Enough For Dinosaurs

May 10, 2020 by 9 Comments

It’s said that slow internet is worse than no internet at all, which is mainly a matter of continuously crushing all hope and sanity vs. finding peace in accepting a fate out of your control. Plus, you can easily pass the time of being catapulted back to the prehistoric ages by navigating a jumpy little creature from that same age through a field of cacti — at least if you’re using Chrome or Chromium. But neither a browser nor actually an operating system are really necessary for that, as [franeklubi] shows with a boot sector implementation of the same game.

Sure, the graphics aren’t quite on par, but compared to the original’s 3000+ lines of JavaScript, [franeklubi] managed to implement it in a few hundred lines of assembly, and was of course constrained by the 512 bytes of the boot sector itself (well, 510 plus the signature). This constraint causes a few limitations, like a slight lack of randomness in the obstacle arrangements, and a constant running speed, but it also makes it the perfect playground and starting point to delve into the world of nifty knacks and hacks, trying to squeeze every last byte.

If you want to give it a try for yourself, all you need is NASM and QEMU — and while you’re at it, why not have some Tetris along the way? We could also see this nicely combined with the real-world jumping version from a few weeks back, and turn it into a standalone arcade game. Bounce Crouch Revolution anyone?

Help Us Throw More Cycles At The Coronavirus Problem

May 10, 2020 by 45 Comments

The Hackaday community has answered the call and put their computers put to work folding proteins found in the coronavirus. Team_Hack-a-Day ranks #44 in the world so far this month, and I’ve seen us rank as high as #19 on 24-hour leaderboards.

Want to join the fight? Donate some of those computing cycles you’re not using to battling SARS‑CoV‑2. You’re probably not an epidemiologist or a vaccine researcher, but you can make their jobs easier by providing them with the data they need through the Folding@home Project.

As Dan Maloney explained in his excellent article on protein folding, understanding the incredibly complex folding behavior of the proteins in the virus will be key to finding treatments and possibly a vaccine. Folding@home connects countless computers via the internet and is now the largest supercomputer in the world, consisting of over 3.5 million CPUs and over half a million GPUs. The resulting data is freely available to researchers.

Let’s take a look at how easy it is to get up and running, how a GPU can supercharge a setup, and dip into the stats for Team_Hack-a-Day’s effort.

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Pulling A Crystal By Grinding It

May 10, 2020 by 29 Comments

If you own a radio transmitter, from a $10 Baofeng handheld to a $1000 fancy all-band transceiver, setting the frequency is simply a case of dialing in where you want to go. A phase-locked-loop frequency synthesizer or a software-defined radio will generate your frequency, and away you go. There was a time though when synthesizers were impossibly complex and radio amateurs were faced with a simple choice. Use an LC oscillator and put up with drifting in frequency, or use a crystal oscillator, and be restricted to only the frequencies of the crystals you had. [Mark Erdle, AE2EA] modified a 1950s broadcast AM broadcast transmitter for the 1.8MHz amateur band, and his friend [Andy Flowers, K0SM] thought it needed its crystal back for originality rather than the external frequency source [Mark] had provided. He documents the process of modifying a crystal oven and moving a crystal frequency in the video below the break.

A crystal oven is a unit containing the crystal itself alongside a thermostatic heater, and in this one, the crystal was a 1970s-vintage hermetically sealed HC6 device. He modified the oven to take a socket for older FT243 crystals because the quartz element can easily be accessed. [Andy] picked a crystal as close as he could find below the required frequency. He then ground it down with very fine grit on a glass plate, reducing its mass and thus its resonant frequency. We’re taken through the process of getting it close to frequency, but sadly don’t see the etching that he uses for the very last stage. At the end of the video, we see a QSO on the transmitter itself, which is something of an oddity in an age when AM on amateur bands has been supplanted by other modes for decades.

If you’re curious about the transmitter there’s a video thread following its restoration, and if the guts of older radio gear interests you then take a look at this aircraft receiver lovingly brought back to life.

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Turn An Unused Pi Zero Into A Parts Bin WiFi Extender

May 10, 2020 by 17 Comments

We know a lot of you are sitting on an unused Raspberry Pi Zero W, maybe even several of them. The things are just too small and cheap not to buy in bulk when the opportunity presents itself. Unfortunately, the Zero isn’t exactly a powerhouse, and it can sometimes be tricky to find an application that really fits the hardware.

Which is why this tip from [Tejas Lotlikar] is worth taking a look at. Using the Pi Zero W, a cheap USB WiFi adapter, and some software trickery, you can put together a cheap extender for your wireless network. The Pi should even have a few cycles left over to run ad-blocking software like Pi-hole while it shuffles your packets around the tubes.

[Tejas] explains every step of the process, from putting the Raspbian image onto an SD card to convincing wpa_supplicant to put the Pi’s WiFi radio into Access Point mode. Incidentally, this means that you don’t need to be very selective about the make and model of the USB wireless adapter. Something with an external antenna is preferable since it will be able to pull in the weak source signal, but you don’t have to worry about it supporting Soft AP.

With the software configured, all you need to finish this project off is an enclosure. A custom 3D printed case large enough to hold both the Pi and the external WiFi adapter would be a nice touch.

Reverse Engineering Saves Trashed LED Panels

May 9, 2020 by 8 Comments

While out riding his bike, [Hammond Pearce] came across a dumpster overflowing with large LED panels. Despite the fact that the model numbers didn’t reveal anything helpful after some online searching, he decided to pedal off with as many as he could safely carry. The COVID-19 lockdown left him with only a limited set of tools, be he still managed to crack the protocol used to control his e-waste score and document it for our reading pleasure.

Between the helpful labels on the PCB silkscreen and the advice of a friend that used to work on digital road signs, it didn’t take [Hammond] long to get a general idea of what the panels were looking for in terms of power and control. Especially once he noticed the MBI5024 shift registers dotting the board.

The next step was to take an ATmega328PB based development board and start throwing data at the panel’s input lines to see if he could elicit a response. With careful attention and some custom code, he eventually figured out that each byte of data sent down the line would control a 4 x 2 section of LEDs.

Once he had the basics down, the next step was to start expanding his code to handle things like shapes, text, and daisy-chained panels. After posting some of his work to Reddit, cyber-sleuths determined that the protocol appeared to be some variation of HUB75, which gave [Hammond] hints on what some of the other pins in the connector might be used for. He’s released all of his code online for anyone who might find it useful, but since he still doesn’t know who made these panels and why there’s really no telling how many of them are actually floating around out there.

Figuring out how to talk to an unknown or undocumented piece of hardware can be intimidating, but success stories like these are reminders of why it’s worth putting the effort in. As we’ve seen, the difference between trash and treasure is often a keen eye and a few lines of code.

Nightmare Fuel Telepresence ‘Bot May Become Your Last Friend

May 9, 2020 by 15 Comments

After this pandemic thing is all said and done, historians will look back on this period from many different perspectives. The one we’re most interested in of course will concern the creativity that flourished in the petri dish of anxiety, stress, and boredom that have come as unwanted side dishes to stay-at-home orders.

[Hunter Irving] and his brother were really missing their friends, so they held a very exclusive hackathon and built a terrifying telepresence robot that looks like a mash-up of Wilson from Castaway and that swirly-cheeked tricycle-riding thing from the Saw movies. Oh, and to make things even worse, it’s made of glow-in-the-dark PLA.

Now when they video chat with friends, TELEBOT is there to make it feel as though that person is in the room with them. The Arduino Uno behind its servo-manipulated vintage doll eyes uses the friend’s voice input to control the wind-up teeth based on their volume levels. As you might imagine, their friends had some uncanny valley issues with TELEBOT, so they printed a set of tiny hats that actually do kind of make it all better. Check out the build/demo video after the break if you think you can handle it.

Not creepy enough for you? Try building your own eyes from the ground up.

Continue reading “Nightmare Fuel Telepresence ‘Bot May Become Your Last Friend” →