Raspberry Pi Floppy Driver Uncovers Fishy Secrets

A forum post by New Zealand electronics enthusiast [zl2wrw] about retreiving waypoints from a mysterious floppy disk caught our eye. The┬ánavigation system on his friend’s fishing boat had died and was replaced. But the old waypoints were stored on a 3-1/2 inch floppy disk that was unreadable on a normal PC. Not to be deterred, [zl2wrw] then looked for another solution — apparently a list of hot NZ fishing spots is worth quite the effort.

The tool he discovered, and the main point of this story, is the bbc-fdc by [Jasper Renow-Clarke] aka [picosonic]. [Jasper] made this project to read 5-1/4 inch Acorn DFS floppies from his BBC Micro. But bbc-fdc can be used to read a variety of floppy disk formats, such as DOS, C64, Apple II, and others It can also just capture raw magnetic flux transitions on the disk, blissfully unaware of any logical structure to the data. We recently wrote about another Raspberry Pi Floppy Drive Controller project┬áby [Scott Baker]. What sets [picosonic]’s project apart is that he’s not using an FDC controller chip here. The only interface electronics is a couple of open-collector 7406 ICs. Data is read using the SPI peripheral. If you need to archive old floppy disks or do a forensic analysis of unknown disks like [zl2wrw], then one of these two projects will almost certainly do the trick.

Meanwhile back in New Zealand, [zl2wrw] discovered that the floppy format was standard (Modified Frequency Modulation, MFM) by examining the raw flux dump. However, the filesystem was a mystery — it didn’t quite match any of the usual suspects. So [zl2wrw] dug into the hex dump of the data and figured out enough of the structure to manually recover the waypoints. Subsequently, a user on the forum found a document describing the file system used by Furuno GPS units, which proved to be a close match albeit after the fact. Alas, [zl2wrw] hasn’t publish the coordinates of those good fishing spots.

Have you had any successes (or failures) when it comes to reading data from old disks? Or have you encountered peculiar disk formats and/or file systems, where having a tool like this could have been helpful? Let us know in the comments below.

Review: Inkplate 6PLUS

While the price of electronic paper has dropped considerably over the last few years, it’s still relatively expensive when compared to more traditional display technology. Accordingly, we’ve seen a lot of interest in recovering the e-paper displays used in electronic shelf labels and consumer e-readers from the likes of Amazon, Barnes & Noble, and Kobo. Unfortunately, while these devices can usually be purchased cheaply on the second hand market, liberating their displays is often too complex a task for the average tinkerer.

Enter the Inkplate. With their open hardware ESP32 development board that plugs into the e-paper displays salvaged from old e-readers, the team at e-radionica is able to turn what was essentially electronic waste into a WiFi-enabled multipurpose display that can be easily programmed using either the Arduino IDE or MicroPython. The $99 Inkplate 6 clearly struck a chord with the maker community, rocketing to 926% of its funding goal on Crowd Supply back in 2020. A year later e-radionica released the larger and more refined Inkplate 10, which managed to break 1,000% of its goal.

For 2021, the team is back with the Inkplate 6PLUS. This updated version of the original Inkplate incorporates the design additions from the Inkplate 10, such as the Real-Time-Clock, expanded GPIO, and USB-C port, and uses a display recycled from newer readers such as the Kindle Paperwhite. These e-paper panels are not only sharper and faster than their predecessors, but also feature touch support and LED front lighting; capabilities which e-radionica has taken full advantage of in the latest version of their software library.

With its Crowd Supply campaign recently crossing over the 100% mark, we got a chance to go hands-on with a prototype of the Inkplate 6PLUS to see how e-radionica’s latest hacker friendly e-paper development platform holds up.

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RF Burns And Exploding PC Speakers: Sophos Looks At The Evidence

Every year in the month of June, someone by the unlikely name of [R.F. Burns] posts a question to the Linux Kernel Mailing List asking whether a Linux kernel module is possible that would blow the PC speaker. It’s fairly obviously a joke, which is why the UK-based anti-virus company Sophos have devoted a light-hearted blog post to it.

The post is an interesting diversion into early PC sounds, when the only hardware guaranteed to be present was a small speaker hooked up to a bit on an output port. The bit could be cycled for square wave beeps, or with a lot of clever manipulation could put out a low-bitrate PWM that delivered almost intelligible sounds including music and voice. They conclude that since the speaker would have been designed to be at the full amplitude of the 5-volt output bit all the time it should be impossible to blow it from software, and we’d be inclined to agree. There’s a remote possibility that some speakers might have a resonant frequency that could be found in software, but we’re not entirely convinced.

Your Hackaday scribe might have spent a while in a university computer lab back in the day trying and failing to write C code that would produce a usable PWM on an XT speaker, but those with long memories might recall the PC speaker driver for Windows 3.1. If you’re a fan of chiptune music there are even entire albums written for this most basic of instruments.

Header image: MKFI, Public domain.

Even With AC, Hazmat Suit Isn’t Really Cool

We’ll admit that the coolness factor of an air conditioned faux spacesuit made out of a hazmat suit will largely depend on where you wear it. At your next chess club meeting, maybe a hit. On a blind date, probably not. [Saveitforparts] apparently doesn’t mind and the combination of very warm weather and the donation of an expired hazmat suit, spurred his imagination as you can see in the video below.

A battery pack, a blower, and a box full of frozen water bottles completes the ensemble. Wireless temperature sensors show the outside temperature as well as temperature inside different parts of the suit. Does it work? We guess it must, but the roar of the fan is deafening and we have doubts about the frozen water cooling system. On the other hand, if you’re shooting a low budget science fiction thriller, this might be just the thing.

Even [Saveitforparts] admits this isn’t really practical and, as we suspected, he decided to get out of it as the condensing water started to run down his legs. Turns out astronauts and tank drivers use an undergarment made with small tubes of flowing water to stay cool.

This project reminded us of the positive pressure suit we saw a bit ago. Not to mention the one that went full body.

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