Spectrum Chiptunes On An STM

June 7, 2019 by Jenny List 5 Comments

Some of us here at Hackaday are suckers for a bit of chiptune music as the backdrop for many excellent times. The authentic way to create chiptunes is of course the original hardware, but in 2019 it’s far more common to do so with an emulator on a modern computer. That computer doesn’t have to sport a high-end processor and desktop operating system though, as [Deater] shows us with his ZX spectrum chiptune player on an STM32L46G Discovery board.

The impetus for the project came he tells us while teaching students to code simple sine wave music players, having code already in the bag for emulating the classic AY-3-8910 sound chip on the Raspberry Pi and the Apple II he decided to port that to the STM32L476 dev board. An earlier version used the internal DAC, but this was refined to send I2S data to an external DAC. The code can be had from GitHub (confusingly buried among code for an LED driver), and we’ve attached a video below of it playing some chiptune goodness.

Of course, Sinclair chiptunes don’t grab all the limelight. There have been plenty of Nintendo and Sega players too. You might also recognize [Deater] from his non-chiptune work, porting Portal to the Apple ][.

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Simple Arduino Universal Remote Control

June 4, 2019 by Tom Nardi 11 Comments

The infrared remote control might not hold the seat of honor in the average home theater setup that it once enjoyed, but it’s not quite out to pasture yet. After all, what are you going to use to stop Netflix once the Chromecast invariably disconnects from your phone? As long as there are devices out there that will respond to commands blasted their way via an IR LED, hackers will be looking to get in on the action.

In an effort to make IR remote hacking just a bit easier, [sjm4306] has submitted his Remoteduino for the 2019 Hackaday Prize. With this handy tool in your arsenal, you can focus on developing the software side of your next IR remote project without worry about the hardware. Just upload your code, and get clicking.

As you might imagine, the design is rather simple. On the front edge of the PCB you’ve got the prerequisite IR LED, and a healthy supply of tactile buttons that your code can use as input. The remote features a fairly standard layout on the top half, complete with silkscreened labels for the common functions, but below that [sjm4306] has packed in six general purpose buttons that can be used for whatever you like.

The Remoteduino is powered by an ATmega328P, and the whole thing runs on a CR2032 cell mounted on the backside. [sjm4306] mentions in his write-up on Hackaday.io that battery life was always a consideration during development of the Remoteduino, so he’s made a few energy-saving considerations. Using the internal 8 MHz oscillator instead of an external crystal shaved a bit off the top, and the aggressive sleep routines got him the rest of the way. In testing, he estimates the battery should last a few years even with daily use.

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Freeform ESP8266 Network Attached Data Display

May 31, 2019 by Tom Nardi 10 Comments

Like many of us, [Josef Adamčík] finds himself fascinated with so-called “freeform” electronic designs, where the three dimensional circuit makes up sections of the device’s structure. When well executed, such designs really blur the line between being a practical device and an artistic piece. In fact his latest design, an ESP8266 MQTT client, would seem to indicate there might not be much of a “line” at all.

The inspiration for this project actually comes from something [Josef] had worked on previously: an ESP8266-based environmental monitoring system. That device had sensors to pick up on things such as humidity and ambient light level, but it didn’t have a display of its own; it just pushed the data out onto the network using MQTT. So he thought a companion device which could receive this environmental data and present it to him in a unique and visually appealing way would be a natural extension of the idea.

As the display doesn’t need any local sensors of its own, it made the design and construction much easier. Which is not to say it was easy, of course. In this write-up, [Josef] takes the reader through the process of designing each “layer” of the circuit in 2D, printing it out onto paper, and then using that as a guide to assemble the real thing. Once he had the individual panels done, he used some pieces of cardboard to create a three dimensional jig which helped him get it all soldered together.

On the software side it’s pretty straightforward. It just pulls the interesting bits of information off of the network and displays it on the OLED. Right now it’s configured to show current temperature on the display, but of course that could be changed to pretty much anything you could imagine if you’re looking to add a similar device to your desktop. There’s also a red LED on the device which lights up to let [Josef] know when the batteries are getting low on the remote sensor unit; a particularly nice touch.

If you’d like to see more of these freeform circuits, we’d advise you to checkout the finalists for our recently concluded “Circuit Sculpture” contest. Some of the finalists are truly beyond belief.

SerialPlot Does Exactly What You Think It Does

May 30, 2019 by Zoe Skyforest 12 Comments

The serial port remains a hacker staple, being one of the easiest ways to move a little bit of data from one machine to another. All manner of projects use the interface, and often, sensors are connected and their data read over such connections. In these cases, it can be useful to plot said data, and SerialPlot is a tool that can do just that.

SerialPlot is capable of reading data over several serial ports at once, and plotting it for your viewing pleasure. It’s capable of interpreting data in a variety of integer and float formats, and plotting multiple channels in a synchronised manner. It’s also capable of sending basic commands out over the serial port, which can be used to trigger or control attached equipment.

Overall, it’s a useful utility for anyone with an array of sensor’s connected over the most classic of interfaces. Of course, if you’re having trouble keeping track of all your serial ports, there’s a utility to help with that, too.

Tiny Two-Digit Thermometer Has Long Battery Life

May 29, 2019 by Donald Papp 20 Comments

Like most of his work, this tiny two-digit thermometer shows that [David Johnson-Davies] has a knack for projects that make efficient use of hardware. No pin is left unused between the DS18B20 temperature sensor, the surface mount seven-segment LED displays, and the ATtiny84 driving it all. With the temperature flashing every 24 seconds and the unit spending the rest of the time in a deep sleep, a good CR2032 coin cell should power the device for nearly a year. The board itself measures only about an inch square.

You may think that a display that flashes only once every 24 seconds might be difficult to actually read in practice, and you’d be right. [David] found that it was indeed impractical to watch the display, waiting an unknown amount of time to read some briefly-flashed surprise numbers. To solve this problem, the decimal points flash shortly before the temperature appears. This countdown alerts the viewer to an incoming display, at the cost of a virtually negligible increase to the current consumption.

[David]’s project write-up explains how everything functions. He also steps through the different parts of the source code to explain how everything works, including the low power mode. The GitHub repository holds all the source files, and the board can also be ordered direct from OSH Park via their handy shared projects feature.

Low power consumption adds complexity to projects, but the payoffs can easily be worth the time spent implementing them. We covered a detailed look into low power WiFi microcontrollers that is still relevant, and projects like this weather station demonstrate practical low power design work.

ESP8266 Upgrade Gives IKEA LEDs UDP Superpowers

May 27, 2019 by Tom Nardi 39 Comments

It can be difficult to resist the impulse buy. You see something interesting, the price is right, and even though you know you should do your research first, you end up putting it in your cart anyway. That’s how [Tobias Girstmair] ended up being the not-so proud owner of a LEDBERG RGB LED strip from IKEA, and what eventually pushed him to replace wimpy original controller with an ESP8266.

So what was the problem with the original controller? If you can believe it, it was incapable of producing white light. When IKEA says an LED is multi-color, they apparently mean it’s only multi-color. A quick check of the reviews online seem to indicate that the white version is sold as a different SKU that apparently looks the same externally and has confused more than a few purchasers.

Rather than having to pick one or the other, [Tobias] decided he would replace the original controller with an ESP-03, hoping that would give him granular enough control over the LEDs to coax a suitably white light out of them. He didn’t want to completely start from scratch, so one of the first decisions he made was to reuse the existing PCB and MOSFETs. Some handy test points on the PCB allowed him to hook the digital pins of the ESP right to the red, blue, and green LED channels.

Then it was just a matter of coming up with the software. To keep things simple, [Tobias] decided to create a “dumb” controller that simply sets the LED color and intensity according to commands it receives over a simplified UDP protocol. Anything beyond that, such as randomized colors or special effects, is done with scripts that run on his computer and fire off the appropriate UDP commands. This also means he can manually control his newly upgraded LEDBERG strips from basically anything that can generate UDP packets, such as an application on his Android phone.

It might not be the most robust implementation we’ve ever seen, but all things considered, it looks as though this modification could be a pretty good way to get some cheap network controlled RGB lighting in your life.

Feather Plus Blackberry Equals Open Source Fauxberry

May 24, 2019 by Brian Benchoff 16 Comments

The keyboard is a superior means of input, but to date no one has really figured out how to make a keyboard for small, handheld electronics. You could use tact switches, but that’s annoying, or you could use a touch screen. The best option we’ve seen is actually a Blackberry keyboard, and [arturo182] has the best example yet. It’s a small handheld device with a screen, keyboard, and WiFi that’s ready to do anything imaginable. Think of it as an Open Source Fauxberry. In any case, we want it.

This project is actually a breakout board of sorts for the Adafruit Feather system, and therefore has support for WiFi, cellular, or pretty much any other networking of connectivity. To this blank canvas, [arturo] added an accelerator/magnetometer sensor, a single Neopixel, and of course the beautiful Blackberry keyboard. This keyboard is attached to an ATSAMD20G, a microcontroller with a whole bunch of I/O that translates key presses into I2C for the Feather.

Aside from that, there’s also a gigantic screen to display just about anything you would want in a portable computing device. There’s still a bit more work to do on this project, most notable figuring out where the battery goes, but [arturo] is developing everything in a livestream, someting we love to see as it really puts a focus on how much effort goes into making custom hardware.