The World’s First DIY Minicomputer Was Almost Australian

The EDUC-8, a DIY minicomputer design that came out in “Electronics Australia” magazine, was almost the world’s first in August 1974. And it would have been tied for the world’s first if inventor [Jamieson “Jim” Rowe] hadn’t held back from publishing to rework the design to expand the memory to a full 256 bytes. The price of perfectionism?

Flash forward 50 years, and [Gwyllym Suter] has taken on the job of recreating the EDUC-8 using modern PCBs, but otherwise staying true to the all-TTL design. He has all of his schematics up on the project’s GitHub, but has also sent us a number of beauty shots that we’re including below. Other than the progress of PCB tech and the very nice 3D-printed housing, they look identical. We have to admit that we love those wavy hand-drawn traces on the original, but we wouldn’t be sad about not having to solder in all those jumpers.

Continue reading “The World’s First DIY Minicomputer Was Almost Australian”

Supercon 2023: Reverse Engineering Commercial Coffee Machines

There was a time when a coffee vending machine was a relatively straightforward affair, with a basic microcontroller doing not much more than the mechanical sequencer it replaced. A modern machine by contrast has 21st century computing power, with touch screens, a full-fat operating system, and a touch screen interface. At Hackaday Supercon 2023, [Kuba Tyszko] shared his adventures in the world of coffee, after reverse engineering a couple of high-end dispensing machines. Sadly he doesn’t reveal the manufacturer, but we’re sure readers will be able to fill in the gaps.

Under the hood is a PC running a Linux distro from a CF card. Surprisingly the distros in question were Slax and Lubuntu, and could quite easily be investigated. The coffee machine software was a Java app, which seems to us strangely appropriate, and it communicated to the coffee machine hardware via a serial port. It’s a tale of relatively straightforward PC reverse engineering, during which he found that the machine isn’t a coffee spy as its only communication with its mothership is an XML status report.

In a way what seems almost surprising is how relatively straightforward and ordinary this machine is. We’re used to quirky embedded platforms with everything far more locked down than this. Meanwhile if hacking vending machines is your thing, you can find a few previous stories on the topic.

Continue reading “Supercon 2023: Reverse Engineering Commercial Coffee Machines”

Studying The Finer Points Of 3D Printed Gears

[How to Mechatronics] on YouTube endeavored to create a comprehensive guide comparing the various factors that affect the performance of 3D printed gears. Given the numerous variables involved, this is a challenging task, but it aims to shed light on the differences. The guide focuses on three types of gears: the spur gear with straight teeth parallel to the gear axis, the helical gear with teeth at an angle, and the herringbone gear, which combines two helical gear designs. Furthermore, the guide delves into how printing factors such as infill density impact strength, and it tests various materials, including PLA, carbon fiber PLA, ABS, PETG, ASA, and nylon, to determine the best options.

The spur gear is highly efficient due to the minimal contact path when the gears are engaged. However, the sudden contact mechanism, as the teeth engage, creates a high impulse load, which can negatively affect durability and increase noise. On the other hand, helical gears have a more gradual engagement, resulting in reduced noise and smoother operation. This leads to an increased load-carrying capacity, thus improving durability and lifespan.

It’s worth noting that multiple teeth are involved in power transmission, with the gradual engagement and disengagement of the tooth being spread out over more teeth than the spur design. The downside is that there is a significant sideways force due to the inclined angle of the teeth, which must be considered in the enclosing structure and may require an additional bearing surface to handle it. Herringbone gears solve this problem by using two helical gears thrusting in opposite directions, cancelling out the force.

Continue reading “Studying The Finer Points Of 3D Printed Gears”

Displays We Love Hacking: DSI

We would not be surprised if DSI screens made up the majority of screens on our planet at this moment in time. If you own a smartphone, there’s a 99.9% chance its screen is DSI. Tablets are likely to use DSI too, unless it’s eDP instead, and a smartwatch of yours definitely will. In a way, DSI displays are inescapable.

This is for a good reason. The DSI interface is a mainstay in SoCs and mobile CPUs worth their salt, it allows for higher speeds and thus higher resolutions than SPI ever could achieve, comparably few pins, an ability to send commands to the display’s controller unlike LVDS or eDP, and staying low power while doing all of it.

There’s money and power in hacking on DSI – an ability to equip your devices with screens that can’t be reused otherwise, building cooler and cooler stuff, tapping into sources of cheap phone displays. What’s more, it’s a comparably underexplored field, too. Let’s waste no time, then!

Decently Similar Internals

DSI is an interface defined by the MIPI Alliance, a group whose standards are not entirely open. Still, nothing is truly new under the sun, and DSI shares a lot of concepts with interfaces we’re used to. For a start, if you remember DisplayPort internals, there are similarities. When it comes to data lanes, DSI can have one, two or four lanes of a high-speed data stream; smaller displays can subsist with a single-lane, while very high resolution displays will want all four. This is where the similarities end. There’s no AUX to talk to the display controller, though – instead, the data lanes switch between two modes.

Continue reading “Displays We Love Hacking: DSI”

Baldur’s Gate III Comes To The TRS-80 Model 100

To say that Tandy’s TRS-80 Model 100 was an influential piece of computer hardware would be something of an understatement. While there’s some debate over which computer can historically be called the “first laptop”, the Model 100 was early enough that it helped influence our modern idea of portable computing. It was also one of the most successful of these early portables, due in part to how easy it was to write your own software for it using the built-in BASIC interpreter.

But as handy and capable as that integrated development environment might have been, it never produced anything as impressive as this Baldur’s Gate III “demake” created by [Alex Bowen]. Written in assembly, the game’s engine implements a subset of the Dungeons & Dragons Systems Reference Document (SRD), and is flexible enough that you could use it to produce your own ASCII art role-playing game that can run on either a Model 100 emulator like Virtual-T or on the real hardware.

Continue reading Baldur’s Gate III Comes To The TRS-80 Model 100″

Remixed Pi Recovery Kit V2 Offers Another Path

Just a few months after releasing the long-awaited second version of his Raspberry Pi Recovery Kit, [Jay Doscher] is back with an alternate take on his latest Pi-in-a-Pelican design. This slightly abridged take on the earlier design should prove to be easier and cheaper to assemble for those playing along at home while keeping the compromises to a minimum.

Probably the biggest change is that the Raspberry Pi 5 has been swapped out for its less expensive and more abundant predecessor. The Pi 4 still packs plenty of punch, but since it requires less power and doesn’t get as hot, it’s less temperamental in a build like this. Gone is the active cooling required by the more powerful single-board computer, and the wiring to distribute power to the Kit’s internal components has been simplified. The high-end military style connectors have been deleted as well. They looked cool, but they certainly weren’t cheap.

One of the most striking features of the original Recovery Kit was the front-mounted switches — both the networking type that’s intended to help facilitate connecting the Raspberry Pi to whatever hardware is left after the end of the world, and the toggles used to selectively control power to to accessory devices. Both have returned for the Recovery Kit 2B, but they’re also optional, with blank plates available to fill in their vacant spots.

Ultimately, both builds are fairly similar, but there’s enough changes between the two that it will have a notable impact on how much time (and money…) it would take you create one of your own. [Jay] has attempted to offer less intimidating versions of his designs in the past; while other creators take a “one and done” approach to their projects, he seems eager to go back and rethink problems that most others would have considered solved.

From Nissan ICE Pickup To BEV With Nissan Leaf Heart

First run of the motor with battery pack still externally connected.

Last year [Jimmy] got a request from a customer ([Dave]) to help convert a 1998 Nissan Frontier pickup into an electric drive vehicle, with a crashed 2019 Nissan Leaf providing the battery and electric motor for the conversion. He has documented the months-long journey with plenty of photos, as well as a series of videos over at the [EVSwap Conversions] YouTube channel. While the idea sounds easy enough, there’s a lot more to it than swapping out the ICE with an electric motor and sticking some batteries to the bottom of the car somewhere with double-sided tape. The pickup truck got effectively stripped down  and gutted, before the 110 kW (150 HP) motor got installed using an adapter plate.

The donor Leaf’s battery pack came in at a decently sized 40 kWh, which should give the converted Nissan Frontier BEV a range of easily 100 miles. This pack was split up into two packs, which got put into a custom aluminium battery box, each mounted on one side of the driveshaft. The charging port got installed on the front of the car, next to the logo, discreetly behind a panel. The front of the car had much of the openings that were needed for the ICE’s radiator sealed up for reduced air friction, along with the new low-friction tires that got installed. Although this converted car still has a radiator, it only needs to assisting cooling the motor stack (including inverter and charger) when driving slowly or charging, making it far less demanding and thus allows for a more sleek front.

As a bonus, the car still has the manual 5-gear shift, just without a clutch, and the pickup bed can now also tilt, albeit with hydraulics (so far). Considering that it started with a decent 1998 pickup and totaled Nissan Leaf, this is among the cleanest conversions we have seen, not to mention a good use of a crashed BEV.

Thanks to [JohnU] for the tip.

Continue reading “From Nissan ICE Pickup To BEV With Nissan Leaf Heart”