A Z80 Computer At The Next Level

At the close of the 8-bit home computer era there were some machines produced that attempted to bridge the gap between the 8- and 16-bit worlds, either by providing a 16-bit device with a backwards compatibility mode, or an 8-bit one with enhanced capabilities to compete with its newer rivals. These products largely fell by the wayside in the face of new 16-bit only platforms, but they and the various enhanced versions of 8-bit processors that appeared over subsequent decades present a fascinating glimpse of what might have been. It’s a theme [Konstantin Dimitrov] explores with his Z20X computer project, a machine using the Zilog eZ80 processor running at 20 MHz, with 512 kB of external memory, and an interface for a 7″ TFT screen module.

The eZ80 is a more recent development, a pipelined processor capable of much higher clock speeds and addressing up to 16 MB of memory while maintaining software compatibility with the Z80. Had it come to market in the late 1980s it would have been a sensation, but instead it has appeared in embedded computers and perhaps of most interest to Hackaday readers, in TI’s line of programmable calculators.

The Z20X is designed to be a through-hole board, with the only SMD component the eZ80 itself. We can understand the motivation behind this, but at the same time wonder whether its likely builders in 2020 will be people unfazed by SMD assembly. It has a system of processor modules in case of future upgrades, and an expansion backplane with an option of an RC2014-compatible bus. There are also PS/2 keyboard and mouse connectors, a serial bus, and an on-board sound chip. The website is short on details of any software, but we’d expect it to work with the typical Z80 retrocomputer offerings such as a BASIC interpreter and the CP/M operating system.

This machine is likely to appeal to retrocomputing enthusiasts, but had it appeared even without the display in a previous decade it would no doubt have become an object of desire. It does however serve as a reminder that the Z80 line has been updated, and though most of us will have moved on it still offers a few chips that could be of interest. Meanwhile for a comparison, take a look at last year’s review of the latest in the range of RC2014 retrocomputer boards.

Thanks [yNos] for the tip.

Posted in eZ80, retrocomputer, retrocomputing, z80, zilog | Leave a comment

Reaching Serenity: Porting Git To A Homebrew Operating System

Life is all about the little joys — such as waking up in the morning and realizing there’s still plenty of time before you have to actually get up. Or getting up anyway to watch a delightful sunrise as the city slowly wakes up, or as [Andreas Kling] chose, porting your favorite development tool to the operating system you wrote.

With the aesthetics of ’90s UI design and the functionality of a simpler 2000s Unix-style system core in mind, and personal reasons to keep himself busy, [Andreas] started SerenityOS a little while back. Of course, writing your own operating system is always a great educational exercise, but it takes a certain amount of commitment to push it beyond an experimental playground phase. So ideally, you’d eventually want to use it as your actual main system, however, as software developer, [Andreas] was missing one crucial component for that: git. Well, he decided to change that and just port it — and as someone who likes to record his hacking sessions, you can watch him along the way.

Admittedly, watching someone tweaking some build tools and compiler settings would normally sound anything but overly exciting, but it adds a few more layers to it when doing so for a work-in-progress OS written from scratch — from digging into libc implementations to an almost reverse engineering approach to the build environment. If you take pleasure in people’s thought process in problem solving and (spoiler alert) their success, you will enjoy watching [Andreas]. On the other hand, if you’re more curious about a fresh approach at a desktop operating system, SerenityOS itself might be worth looking into. Of course, there are other options for that as well.

Posted in Git, operating system, os, porting, SerenityOS, Software Development | Leave a comment

Hackaday Links: February 23, 2020

If you think your data rates suck, take pity on New Horizons. The space probe, which gave us lovely pictures of the hapless one-time planet Pluto after its 2015 flyby, continued to plunge and explore other, smaller objects in the Kuiper belt. In January of 2019, New Horizons zipped by Kuiper belt object Arrokoth and buffered its findings on the spacecraft’s solid-state data recorders. The probe has been dribbling data back to Earth ever since at the rate of 1 to 2 kilobits per second, and now we have enough of that data to piece together a story of how planets may have formed in the early solar system. The planetary science is fascinating, but for our money, getting a probe to narrowly miss a 35-kilometer long object at a range of 6.5 billion km all while traveling at 51,500 km/h is pretty impressive. And if as expected it takes until September to retrieve all the data from the event at a speed worse than dialup rates, it’ll be worth the wait.

Speaking of space, if you’re at all interested in big data, you might want to consider putting your skills to work in the search for extraterrestrial intelligence. The Berkeley SETI Research Center has been feeding data from the Green Bank Telescope and their Automated Planet Finder into the public archive of Breakthrough Listen, a 10-year, $100 million initiative to scan the million closest stars in our galaxy as well as the 100 nearest galaxies for signs of intelligent life. They’re asking for help to analyze the torrents of data they’re accumulating, specifically by developing software and algorithms to process the data. They’ve set up a site to walk you through the basics and get you started. If you’re handy with Python and have an interest in astronomy, you should check it out.

Staying with the space theme, what’s the best way to get kids interested in space and electronics? Why, by launching a satellite designed to meme its way across the heavens, of course. The Mission for Education and Multimedia Engagement satellite, or MEMESat-1, is being planned for a February 2021 launch. The 1U cubesat will serve as an amateur radio repeater and slow-scan TV (SSTV) beacon that will beam down memes donated to the project and stored on radiation-hardened flash storage. In all seriousness, this seems like a great way to engage the generation that elevated the meme to a modern art form in a STEM project they might otherwise show little interest in.

It looks as though Linux might be getting a big boost as the government of South Korea announced that they’re switching 3.3 million PCs from Windows to Linux. It’s tempting to blame Microsoft’s recent dropping of Windows 7 support for the defenestration, but this sounds like a plan that’s been in the works for a while. No official word on which distro will be selected for the 780 billion won ($655 million) effort, which is said to be driven by ballooning software license costs and a desire to get out from under Microsoft’s thumb.

And finally, in perhaps the ickiest auction ever held, the “Davos Collection” headed to the auction block this week in New York. The items offered were all collected from the 2018 World Economic Forum in Davos, Switzerland, where the world’s elites gather to determine the fate of the 99.999%. Every item in the collection, ranging from utensils and glassware used at the many lavish meals to “sanitary items” disposed of by the billionaires, and even hair and fluid samples swabbed from restrooms, potentially holds a genetic treasure trove in the form of the DNA it takes to be in the elite. Or at least that’s the theory. There’s a whole “Boys from Brazil” vibe here that we find disquieting, and we flatly refuse to see how an auction where a used paper cup is offered for $8,000 went, but if you’d like to virtually browse through the ostensibly valuable trash of oligarchs, check out the auction catalog.

Posted in amateur radio, Arrokoth, beacon, big data, Davos, defenestration, dna, Elite, flyby, genetics, Hackaday Columns, Hackaday links, linux, Meme, New Horizons, oligarchy, Pluto, repeater, SETI, SSTV | Leave a comment

An Open Source Ebike

In the ebike world, there are two paths. The first is a homemade kit bike with motors and controllers from China. The second is a prebuilt bike from a manufacturer like Giant, with motors and controllers from China, which will be half as fast and cost three times as much. The choice is obvious, and there are other benefits to taking the first path as well, such as using this equipment which now has an open source firmware option.

The Tong Sheng TSDZ2 drive is popular in the ebike world because it’s an affordable kit motor which has a pedal-assist mode using torque sensors, resulting in a more polished experience. In contrast, other popular kit motors tend to rely on less expensive cadence sensors which are not as smooth or intuitive. This new open source firmware for the TSDZ2 further improves on the ride by improving the motor responsiveness, improving battery efficiency, and opening up the ability to use any of a number of color displays. (More information is available on a separate Wiki.)

If you have a TSDZ2-based ebike it might be time to break out the laptop and get to work installing this firmware. If you’re behind the times and still haven’t figured out that ebikes are one of the best ways to travel, here is the proof you need.

Thanks to [coaxial] for the tip! Photo via Reddit user [PippyLongSausage].

Posted in bicycle, china, ebike, efficiency, firmware, mid drive, news, open source, tong sheng, transportation hacks, tsdz2, upgrade | Leave a comment

The Smallest Cell Phone Picture

Mobile phones are the photography tool for most of us, but they are a blunt tool. If you love astrophotography, you buy a DSLR and a lens adapter. Infrared photography needs camera surgery or a special unit. If you want to look closer to home, you may have a microscope with a CCD. Your pocket computer is not manufactured for microscopy, but that does not mean it cannot be convinced. Most of us have held our lens up to the eyepiece of some binoculars or a microscope, and it sort of works, but it is far from perfect. [Benedict Diederich] and a team are proving that we can get darn beautiful images with a microscope, a phone holder, and some purpose-built software on an Android phone with their cellSTORM.

The trick to getting useful images is to compare a series of pictures and figure out which pixels matter and which ones are noisy. Imagine someone shows you grainy nighttime footage from an outdoor security camera. When you pause, it looks like hot garbage, and you can’t tell the difference between a patio chair and a shrubbery. As it plays, the noisy pixels bounce around, and you figure out you’re looking at a spruce bush, and that is roughly how the software parses out a crisp image. At the cost of frame rate, you get clarity, which is why you need a phone holder. Some of their tests took minutes, so astrophotography might not fare as well.

We love high-resolution pictures of tiny things and that isn’t going to change anytime soon.

Thank you [Dr. Nicolás De Francesco] for the tip.

Posted in 80nm, cell phone, Cellphone Hacks, cellSTORM, dSTORM, Huawei, microscopy, mobile phone, P9, phone hacks, superresolution, tensor flow, tensorflow | Leave a comment

Gesture Control The Easy Way

Gesture control is a technology that has floated around for quite a while, but never quite reached mainstream acceptance. Wii Bowling was fun for a while, but we’re not regularly using gestures to open doors or order pizza just yet. Doing it yourself can be quite easy, however, as [RC Lover san] found with a barebones, hacky build.

Typically, when we think of gesture control, we envisage object tracking cameras or MEMS accelerometers. Instead, this build uses simple tilt switches, as you might find in a pinball machine from days of yore. Four of these are placed on a wrist-mounted device, allowing the user to tilt their arm to move an RC car in different directions. The tilt switches are easy to hack into the controller for a toy RC car, as they simply replace the existing buttons on the PCB.

It’s a project that goes to show that not everything has to be done with advanced sensors and complex algorithms. Sometimes, it can all be done with a handful of cheap switches and some ingenuity. Plus, using arm movements to scoot BB-8 around on the floor looks like great fun. We’ve seen other attempts to build simple gesture controls with pots, too. Video after the break.

Posted in gesture, gesture control, toy hacks | Leave a comment

3D Printable Nameplates From Your Web Browser

It’s an unwritten rule that all proper pieces of shop equipment need a nameplate. Otherwise, how are you going to know what name to use when you curse it under your breath? In the old days these would have been made out of something fancy such as brass, but for the modern hacker that doesn’t stand on tradition, you can now easily outfit all your gear with custom 3D printed nameplates using this online tool.

Granted, it wouldn’t be very difficult to throw one of these together in whatever CAD package you happen to have access to. But with the tool [Tobias Weber] has developed, you don’t have to. Simply pick the font, the shape of the border, and fill in a few variables to fine tune things such as padding and base thickness.

Finally, enter your text and marvel at the real-time 3D preview that’s rendered thanks to the magic of modern web technologies. In seconds, you’ll have an STL file that’s ready for the warm liquid goo phase.

The huge collection of fonts are a particularly nice touch, ranging from delicate scripts to military style stencils. Depending on your CAD software, getting arbitrary fonts imported and extruded into a three dimensional shape can be tricky for new players. If we do have one complaint though, it’s that there doesn’t seem to be a clear indicator of how big the nameplate is going to be when exported. First time around, it spit out an STL that would have been 300 mm long if we hadn’t scaled it down in the slicer.

This project is very reminiscent of another web-based tool we featured recently. That one allowed you to make 3D printed QR codes which would whatever entomb in plastic whatever data your cold hacker heart desired.

Posted in 3d Printer hacks, 3d printing, label, nameplate, software hacks, stl, web based | Leave a comment

A High Performance Ski-Sled For The Big Kids

Sledding is a pastime often left to younger humans, though there is no good reason why this must be the case. [JoshXarles] is an adult with a strong enthusiasm for carving up the snow, and set out to build a high-performance sled this winter. 

It’s a ski-based design, and [Josh]’s goal from the outset was to build a rig with serious handling credentials. His favored run features several 180 degree switchbacks, so it’s important to be able to corner well without losing speed. This was achieved by using sidecut skis with a carefully designed steering system, allowing the sled to carve corners in the same way as a downhill skier. The frame of the sled is built out of aluminium box tubing, bolted together to form a strong structure. There’s also attractive wooden decking which completes the look.

The sled performed admirably in initial testing, with good steering feel and plenty of speed downhill. We’d love to try ourselves, weather permitting, of course. There are also electric options for those not blessed with geologically-suitable features to sled down. Video after the break.

Posted in sled, sledge, snow, transportation hacks | Leave a comment

Fun-Size Tesla Might Be The World’s Smallest

We get all kinds of tips about “the world’s something-est” widget, which normally end up attracting the debunkers in droves. So normally, we shy away from making superlative claims about a project, no matter how they bill themselves. But we’re comfortable that this is the world’s smallest Tesla, at least if we have to stretch the definition of Tesla a bit.

This clown-car version of the Tesla Model S that [Austin] built is based around a Radio Flyer replica of the electric sedan. The $600 battery-powered original doesn’t deliver exactly the same neck-snapping acceleration of its full-size cousin, so he stripped off the nicely detailed plastic body and put that onto a heavily modified go-cart chassis. The tiny wheelbase left little in the way of legroom, but with the seat mounted far enough back into the wheelie-inducing zone, it was possible for [Austin] to squeeze in. He chose to pay homage to Tesla’s battery pack design and built 16 modules with fourteen 18650 cells in each, a still-substantial battery for such a small vehicle. Hydraulic brakes were also added, a wise decision since the 4800 Watt BLDC is a little snappier than the stock motor, to say the least. The video below shows the build, as well as a dangerous test ride where the speed read 72 at one point; we’re not sure if that’s MPH or km/h, but either way, it’s terrifying. The drifts were pretty sick too.

It seems [Austin] has the need for speed, and for drifting.  We’ve seen his water-cooled electric drift trike before, as well as his ridiculously overpowered crazy cart.

Posted in 18650, battery, BLDC, go cart, model S, replica, tesla, transportation hacks | Leave a comment

This Mallet Has Backwards Dovetails… That’s Impossible!

Dovetails are a wedge-shaped joint found in woodworking. The wedge makes for strong joinery because a force that tries to pull it apart also increases the friction on the joint. This mallet has dovetails on either side that keep the head from flying off, but there’s also a through tenon in the center. This is an impossible joint as there’s no way to slide the mallet head onto the handle. The two pieces of wood must have grown that way!

As with everything, there’s a trick here, let it scratch your brain for a while before reading on… if you can guess how it’s done it’ll be very satisfying when you confirm your theory. Both the trick of the impossible mallet and the superb hand joinery are shown off in this video from the [Third Coast Craftsman].

The trick comes in the form of internal voids hidden from view once the two pieces of the mallet have been assembled. The through tenon is exactly as you’d expect: a strait tenon slides into a straight mortise in the mallet. The dovetails to either side of the handle and the pockets they mate with in the mallet head are not at all what you’d expect. The edges of the dovetail have been chamfered at 45 degrees so you can’t pull them to the outside of the mallet as you slide them into place. The opposite is the actual trick. Each of the dovetails bends inward until a ramp at the very end of the mallet pocket pushes it back into place.

The impossible mallet isn’t a new concept and stands as a formidable challenge for any accomplished woodworker. The images above are of [Jim Guilford’s] impossible mallet. Here the trick is fully exposed, showing the dovetail tenons of the handle clamped together as it is driven into place. Two things are striking here; the joints cannot be tested and must be perfect before assembly, and there is a real chance the tenons will break or the mallet head will split apart from the force of assembly. This project will test your courage as much as it will your patience.

Posted in dovetail, impossible mallet, joinery, misc hacks, woodworking | Leave a comment