This Snappy 8-Bit Microcomputer Brings The Speed To Retrocomputing

October 21, 2022 by 45 Comments

When the need for speed overcomes you, thoughts generally don’t turn to 8-bit computers. Sure, an 8-bit machine is fun for retro gameplay and reliving the glory days, and there certainly were some old machines that were notably faster than the others. But raw computing power isn’t really the point of retrocomputing.

Or is it? [Bernardo Kastrup] over at The Byte Attic has introduced an interesting machine called the Agon Light, an 8-bit SBC that’s also a bit like a microcontroller. The machine has a single PCB that looks about half as big as an Arduino Uno, and sports some of the same connectors and terminals around its periphery. The heart of the Agon Light is an eZ80 8-bit, 18.432 MHz 3-stage pipelined CPU, which is binary compatible with the Z80. It also has an audio-video coprocessor, in the form of an ESP32-Pico-D4, which supports a 640×480 64-color display and two mono audio channels. There’s no word we could find of whether the ESP32’s RF systems are accessible; it would be nice, but perhaps unnecessary since there are both USB ports and a PS/2 keyboard jack. There’s also a pin header for 20 GPIOs as well as I2C, SPI, and UART for serial communication.

The lengthy video below goes into all the details on the Agon Light, including the results of benchmark testing, all of which soundly thrash the usual 8-bit suspects. The project is open source and all the design files are available, or you can get a PCB populated with all the SMD components and just put the through-hole parts on. [Bernardo] is also encouraging people to build and sell their own Agon Lights, which seems pretty cool too. It honestly looks like a lot of fun, and we’re looking forward to seeing what people do with this.

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This Week In Security: Linux WiFi, Fortinet, Text4Shell, And Predictable GUIDs

October 21, 2022 by 18 Comments

Up first this week is a quintet of vulnerabilities in the Linux kernel’s wireless code. It started with [Soenke Huster] from TU Darmstadt, who found a buffer overwrite in mac80211 code. The private disclosure to SUSE kernel engineers led to a security once-over of this wireless framework in the kernel, and some other nasty bugs were found. A couple result in Denial-of-Service (DOS), but CVE-2022-41674, CVE-2022-42719, and CVE-2022-42720 are Remote Code Execution vulnerabilities. The unfortunate bit is that these vulnerabilities are triggered on processing beacon frames — the wireless packets that announce the presence of a wireless network. A machine doesn’t have to be connected or trying to connect to a network, but simply scanning for networks can lead to compromise.

The flaws were announced on the 13th, and were officially fixed in the mainline kernel on the 15th. Many distros shipped updates on the 14th, so the turnaround was quite quick on this one. The flaws were all memory-management problems, which has prompted a few calls for the newly-merged Rust framework to get some real-world use sooner rather than later.

Fortinet

Much of Fortinet’s lineup, most notable their Fortigate firewalls, has a pre-auth authentication bypass on the administrative HTTP/S interface. Or plainly, if you can get to the login page, you can break in without a password. That’s bad, but at this point, you *really* shouldn’t have any administrative interfaces world-accessible on any hardware. Updated firmware is available.

More than just a couple days have passed, so we have some idea of the root problem and how it was fixed. It’s a simple one — the Forwarded HTTP headers on an incoming request are unintentionally trusted. So just send a request with Forwarded:for and Forwarded:by set to 127.0.0.1, and it falls through into code logic intended for internal API calls. Add a trusted SSH key, and pop, you’re in. Whoops. Continue reading “This Week In Security: Linux WiFi, Fortinet, Text4Shell, And Predictable GUIDs” →

Custom Sony Camera Remote Built With ESP32

October 21, 2022 by 10 Comments

Whether you’re shooting video or photos, having a camera remote can really improve your productivity. No longer do you have to run back to the camera to press its tiny buttons! [Frank Zhao] is a Sony user, so decided to whip up a custom remote using the ESP32 for his Alpha camera, adding special features along the way.

The build communicates with the camera over WiFi, but can fall back to Infrared if there’s an issue with the radio link. It’s built around the M5StickC, which is a pre-built device featuring an ESP32 and a small display in a handheld form factor. It let him build the remote in half the size of the official Sony device. With limited buttons on board, though, he relies on the IMU to control many advanced features with motion gestures.

The remote enables a bunch of functionality that Sony didn’t bake into its cameras from the factory. There’s a sound-activated shutter release, dual shutter mode, and several timer-based tools including astrophotography modes. There’s also a big knob you can add for focus pulls, and a mode to reset the auto-focus when you’re frustrated that it isn’t working properly. Some of the features work better than others, as sometimes, the camera doesn’t respond to commands quickly enough. Regardless, it’s pretty neat that [Frank] has unlocked so much extra functionality with his custom $20 remote.

We’ve seen other homebrewed tools open up new creative possibilities for cameras before, too. If you’ve got your own nifty camera hacks, let us know on the tipsline!

HP-41C, The Forth Edition

October 21, 2022 by 38 Comments

If you have an HP-41 — arguably the best calculator ever made, you might not have noticed that there’s a version of Forth for it. The code was written a while back in assembly and will work on anything that actually emulates the device properly, such as a SwissMicros DM41X. [Calculator Clique] shows you how it works in a recent video that you can watch below.

The original code dates back to 1984, but some recent detective work by [Angel Margin] has the code running again. If you know about synthetic programming on the 41C and the oddities of its internal architecture, you can’t help but be impressed.

Of course, Forth is meant to be easy to port over, but if you read about some of the architectural challenges, you start to realize this could be one of the more difficult implementations you’ve ever seen. Don’t forget you have what is, by today’s standards, an extremely limited amount of resources.

That being said, calling the HP41C a calculator is almost a crime. It is really a tiny computer hiding inside a calculator case. Then again, the best calculators always are.

We wonder if the code would run on an emulated 41C? Were you part of the TI calculator gang? No problem.

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Unconventional Longboard Built From Single Slice Of Tree

October 20, 2022 by 21 Comments

Typically, skateboards and longboards are made out of many laminated layers of wood. This gives them a pleasing flex that produces a comfortable ride. However, it’s not the only way to do things. [DesignCo] went for an unconventional design, using a large slice out of a tree instead.

The benefit of using a section of tree trunk for a board is that it has a very attractive look with all the rings visible. To turn it into a board, it was first roughly cut to shape, before being planed down to a uniform thickness. Further shaping was then achieved with the use of a flap wheel on an angle grinder. The wood was finished with several coats of tung oil before being given a final seal with matte lacquer. A solid steel tail was then prepared to match, shaped with an nice curve and with two bolts screwed in. These bolts were then epoxied into the board, joining the two, and trucks installed underneath.

The final build looks stunning, and is ride-able too. It’s likely a little slipperier than a board with grip tape, and it probably wouldn’t handle bumps as well as a traditional design. Long boards are rarely about performance anyway, though, and this board looks like great fun to get around on.

We’ve seen non-traditional longboards before, too. Video after the break.

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A solar inverter that asks for a password on its display

Decompiling Software To Fix An Old Solar Inverter

October 20, 2022 by 16 Comments

It’s a fact of life that electronic devices become obsolete after a few years. Sometimes this is because technology has moved on, but it can also happen that a perfectly functional device becomes near-useless simply because the original manufacturer no longer supports it. When [Buy It Fix It] found a pair of second-hand Power-One Aurora solar inverters, he ran into an issue for which he needed access to the service menu, which happened to be password-protected. The original manufacturer had ceased to exist, and the current owner of the brand name was unable to help, so [Buy It Fix It] had to resort to reverse engineering to find the password.

Thanks to the Wayback Machine over at the Internet Archive, [Buy It Fix It] was able to download the PC software bundle that originally came with the inverters. But in order to access all features, a password was required that could only be obtained by registering the unit with the manufacturer. That wasn’t going to happen, so [Buy It Fix It] fired up dnSpy, a decompiler and debugger for .NET programs. After a bit of searching he found the section that checked the password, and by simply copying that section into a new program he was able to make his own key generator.

With the service password now available, [Buy It Fix It] was able to set the inverter to the correct voltage setting and hook it up to his solar panels. Interestingly, the program code also had references to “PONG”, “Tetris” and “tiramisu” at various places; these turned out to be Easter eggs in the code, containing simple versions of those two games as well as a photo of the Italian dessert.

Inside the software archive was also another program that enabled the programming of low-level functions within the inverter, things that few users would ever need to touch. This program was not written in .NET but in C or something similar, so it required the use of x32dbg to look at the machine code. Again, this program was password-protected, but the master password was simply stored as the unencrypted string “91951” — the last five digits of the manufacturer’s old phone number.

The inverter was not actually working when [Buy It Fix It] first got it, and his repair video (also embedded below) is also well worth watching if you’re into power electronics repair. Hacking solar inverters to enable more features is often possible, but of course it’s much easier if the entire design is open source.

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A Homebrew AC Upgrade For The Fluke 8840A

October 20, 2022 by 8 Comments

[William Dudley] picked up a Fluke 8840A bench multimeter at an auction, but was sad to find out that it was reading resistances inaccurately. It was also missing the optional board to enable AC measurements. Desiring to use the otherwise lovely meter, he set about repairing and upgrading the device.

Thankfully, the 8840A was from a time when Fluke used to openly publish schematics in its manuals. Thus, combined with taking a look at some photos online, it was straightforward for [William] to recreate the original AC “Option 09” board to enable the desired functionality. As is usually the way, his efforts didn’t work first time, but after some bodge wires were installed, all was well. [William] reports the measurements are “reasonable, maybe even sufficient” with no calibration undertaken.

Repairing the resistance issue was easy. It turned out to be corrosion on the selector switches, revealed when high-resistance measurements were accurate, but low-resistance measurements weren’t. A bit of flick-flacker with some contact cleaner sprayed into the switches got things working again nicely.

It’s nice to see old hardware restored to full functionality, particularly when it’s as attractive and well-built as an old Fluke meter. Bringing back old tools from the dead? You know we wanna hear about it!