4-bit Retrocomputer Emulator Gets Custom PCB

December 23, 2020 by Moritz v. Sivers 4 Comments

It might be fair to suspect that most people who are considered digital natives have very little to no clue about what is actually going on inside their smartphones, tablets, and computers. To be fair, it is not easy to understand how modern CPUs work but this was different at the beginning of the 80s when personal computers just started to become popular. People who grew up back then might have a much better understanding of computer basics thanks to computer education systems. The Busch 2090 Microtronic Computer System released in 1981 in Germany was one of these devices teaching people the basics of programming and machine language. It was also [Michael Wessel]’s first computer and even though he is still in proud possession of the original he just recently recreated it using an Arduino.

The original Microtronic was sold under the catchy slogan “Hobby of the future which has already begun!” Of course, the specs of the 4-bit, 500 kHz TMS 1600 inside the Microtronic seem laughable compared to modern microcontrollers, but it did run a virtual environment that taught more than the native assembly. He points out though that the instruction manual was exceptionally well written and is still highly effective in teaching students the basics of computer programming.

Already, a couple of years back he wrote an Arduino-based Microtronic emulator. In his new project, he got around to extending the functionality and creating a custom PCB for the device. The whole thing is based on ATMega 2560 Pro Mini including an SD card module for file storage, an LCD display, and a whole bunch of pushbuttons. He also added an RTC module and a speaker to recreate some of the original functions like programming a digital clock or composing melodies. The device can also serve as an emulator of the cassette interface of the original Microtronic that allowed to save programs with a whopping data rate of 14 baud.

He has certainly done a great job of preserving this beautiful piece of retro-tech for the future. Instead of an Arduino, retro computers can also be emulated on an FPGA or just take the original hardware and extend it with a Raspberry Pi.

A Tiny LED Matrix Is Better With Friends

December 23, 2020 by Kerry Scharfglass 8 Comments

When we last heard from [lixielabs] he was building Nixie tube replacements out of etched acrylic and LEDs. Well he’s moved forward a few decades to bring us the Pixie, a chainable, addressable backpack for tiny LED matrix displays.

Each Pixie module is designed to host two gorgeous little Lite-On LTP-305G/HR 5×7 LED dot matrix displays, which we suspect have been impulse purchases in many a shopping cart. Along with the displays there is a small matrix controller and an ATTINY45 to expose a friendly electrical interface. Each module is designed to be mounted edge to edge and daisy chained out to 12 or more (with two displays each) for a flexible display any size you need. But to address the entire array only two control pins are required (data and clock).

[lixielabs] has done the legwork to make using those pins as easy as possible. He is careful to point out the importance of a good SDK and provides handy Arduino libraries for common microcontrollers and a reference implementation for the Raspberry Pi that should be easy to crib from to support new platforms. To go with that library support is superb documentation in the form of a datasheet (complete with dimensions and schematic!) and well stocked GitHub repo with examples and more.

To get a sense of their graphical capabilities, check out a video of 6 Pixie’s acting as a VU meter after the break. The Pixie looks like what you get when a hacker gets frustrated at reinventing LED dot matrix control for every project and decided to solve it once and for all. The design is clean, well documented, and extremely functional. We’re excited to see what comes next! Continue reading “A Tiny LED Matrix Is Better With Friends” →

Lidar House Looks Good, Looks All Around

December 20, 2020 by Al Williams 10 Comments

A lighthouse beams light out to make itself and its shoreline visible. [Daniel’s] lighthouse has the opposite function, using lasers to map out the area around itself. Using an Arduino and a ToF sensor, the concept is relatively simple. However, connecting to something that rotates 360 degrees is always a challenge.

The lighthouse is inexpensive — about $40 — and small. Small enough, in fact, to mount on top of a robot, which would give you great situational awareness on a robot big enough to support it. You can see the device in action in the video below. Continue reading “Lidar House Looks Good, Looks All Around” →

Skittle Sorter Makes Long Task Shorter

December 16, 2020 by Lewin Day 11 Comments

One of the most common complaints fielded by the agents of Big Candy regards the non-homogenous nature of their products. Skittles and M&Ms are two egregious offenders in this area, and it’s left up to the determined consumer to handle sorting these candies themselves. Of course, you can always do it by hand, but as we all know – machines will do the work.

This Skittle sorter is the creation of [Lewis] of [DIY Machines], and it’s a build targeted at the beginner level. Constructed out of cardboard, it uses a pair of servos to handle the transport of the candies into their requisite colored bins, via a rotating disc and chute. Skittles are scanned with a TCS34725 color scanner hooked up to an Arduino Nano, which changes the angle of the output chute to dump the candy in the proper location. The hopper is able to handle a standard 180 gram bag of Skittles without problems.

[Lewis] does a great job explaining each stage of the build, from the mechanical and electronic side of things, to the required calibrations to make everything play together nicely. The project teaches builders a multiude of useful lessons, like how to use limit switches and other concepts of automation. We’ve featured [Lewis] on these pages before, too; his stylish shelf clock is a particular delight. Video after the break.

Continue reading “Skittle Sorter Makes Long Task Shorter” →

Automatic Sanitizer For Your Cupholder

December 16, 2020 by Kristina Panos 6 Comments

Why is it so hard to remember to use hand sanitizer between going into the store and driving back home? We tried hanging a bottle off the windshield wiper stalk, but it gets in the way and is hard to use and share with passengers. The ideal thing would be to have a hands-free pump in the car that reminds you to use it.

You don’t have to wire this to the ignition or anything — all you have to do is power it with the cigarette lighter (or straight-up outlet, if you’re lucky). Every time you turn the key, this pump powers up and performs a little song to remind you to use it. Electronically speaking, it couldn’t be simpler — an Arduino UNO reads your hand from the distance sensor and activates a servo that dispenses three short pumps of isopropyl alcohol. Check it out in action after the break.

Want a hands-free solution for the house? Just build something you can step on.

Continue reading “Automatic Sanitizer For Your Cupholder” →

Gigantic Working Arduino Uses 1/4″ Cables

December 11, 2020 by Kristina Panos 25 Comments

What is it about larger-than-life versions of things that makes them so awesome? We’re not sure exactly, but this giant working Arduino definitely has the ‘it’ factor, whatever that may be. It’s twelve times the size of a regular Uno and has a Nano embedded in the back of it. To give you an idea of the scale, the reset button is an arcade button.

The Arduino Giga’s PCB is made of 3/4″ plywood, and the giant components represent a week and a half of 3D printing. The lettering and pin numbers are all carved on a CNC and filled in with what appears to be caulk. They didn’t get carved out deeply enough the first time around, but [byte sized] came up with a clever way to perfectly re-register the plywood so it carved in exactly the same places.

Although we love everything about this build, our favorite part has to be the way that [byte sized] made the female headers work. Each one has a 1/4″ audio jack embedded inside of it (a task which required a special 3D printed tool), so patch cables are the new jumper cables. [byte sized] put it to the test with some addressable RGB LEDs on his Christmas tree, which you can see in the build video after the break.

You can buy one of those giant working 555 timer kits, but why not just make one yourself?

Continue reading “Gigantic Working Arduino Uses 1/4″ Cables” →

Easy Frequency Counter Looks Good, Reads To 6.5 MHz

December 10, 2020 by Al Williams 12 Comments

We were struck by how attractive [mircemk’s] Arduino-based frequency counter looks. It also is a reasonably simple build. It can count up to 6.5 MHz which isn’t that much, but there’s a lot you can do even with that limitation.

The LED display is decidedly retro. Inside a very modern Arduino Nano does most of the work. There is a simple shaping circuit to improve the response to irregular-shaped input waveforms. We’d have probably used a single op-amp as a zero-crossing detector. Admittedly, that’s a bit more complex, but not much more and it should give better results.

Continue reading “Easy Frequency Counter Looks Good, Reads To 6.5 MHz” →