A Dev Board For The ESP Lua Interpreter

January 1, 2015 by 25 Comments

From the great minds behind the NodeMCU Lua interpreter for the ESP8266 comes a proper dev board for the WiFi platform of 2015. They are calling it, the NodeMCU-devkit, and it’s a reasonable, cheap, and breadboardable breakout board for the ESP8266.

The version of ESP8266 used in this project is the ESP-12, the newer, fancier model with RF shielding, a questionable FCC logo, and every single one of the GPIOs exposed on castellated connectors. The rest of the board is a USB to serial converter (the CH340G – probably the cheapest USB to serial chip out there), a few passives, and a USB micro connector. It’s simple, cheap, and open source. You can’t do better than that.

This dev board is explicitly designed to work with the NodeMCU firmware, a Lua-based firmware for the ESP. Already we’ve seen some projects make the Hackaday front page with this firmware. Sure, it’s just a garage door opener, but that’s extremely impressive for a chip that’s only a few months old.

Thanks [Baboon] for the tip.

Spying On The ESP32’s GPIO

January 1, 2024 by 8 Comments

The ESP32 has been a go-to microcontroller platform for a while now, thanks to its versatile capabilities, integrated Wi-Fi and Bluetooth connectivity, and low power consumption. It’s ideal for a wide range of projects especially those revolving around IoT, partially because of all of the libraries and tools available for it now. The latest tool from [The Last Outpost Workshop] adds a feature we didn’t know we wanted until now: a webserver showing real-time updates of what all of the GPIO pins are doing.

The live GPIO pin monitoring library sets up the ESP32 to stream information about what all of the pins are doing in real time to a webserver, which displays the information as a helpful graphic. The demonstration in the video below shows and example troubleshooting a situation where the code is correct but there’s a mistake in the wiring, helping to quickly identify the problem and hopefully eliminating a wild goose chase for a bug in the software. The library can be quickly installed using the Arduino IDE and only requires the use of one other library and a few lines of code to get everything up and running.

As far as a debugging tool goes, something like this could save a lot of us a significant amount of time, especially with how easy it is to set up. A real-time look into the pins and their behavior, including those set up for PWM, is invaluable for plenty of situations. Of course if you’re building something like a real-time operating system that needs responses within a very specific interval you may want to look at more in-depth strategies for probing the GPIO.

Thanks to [Bob] for the tip!

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The Case For A Technology Aware Lobby Correspondent

November 17, 2023 by 24 Comments

We cover all manner of stories here at Hackaday, including awesome hardware hacks, the latest trends and inventions, and in-depth guides to fascinating technologies. We also cover a few news stories from the wider world outside our community, usually when they have some knock-on effect that has an impact on us. Recently this last category of stories has included laws which present a threat to online encryption and privacy in the UK and in the European Union, for example. They’re not the most joyful of news, but it’s vital for everyone with an interest in online matters to be informed about them.

A Long And Inglorious History

A quad flat-pack computer chip, made by VLSI
The infamous Clipper chip. Travis Goodspeed, CC BY 2.0

Those of us who have followed the world of technology will know that badly thought out laws with a negative impact on technology have a long and inglorious history. Some like the infamous backdoored Clipper chip encryption device die an inglorious death as industry or the public succeed in making them irrelevant, but others such as the Digital Millennium Copyright Act or DMCA live on for decades and present an ongoing malign influence. Most recently our ongoing coverage of dubious drone stories included a hefty dose of equally dubious action from lawmakers.

When considering these pieces of legislation it’s easy to characterise the politicians who advance them as gullible idiots easily swayed by any commercial lobbyist with a fistful of cash. But the reality is far more nuanced, while some of them may well be tempted by those lobbyists  they are in most cases neither gullible nor foolish. Instead they are better characterised as clueless on technical issues, and thus easily swayed by received opinion rather than by technological reality. If there’s a fault in the system it’s that the essential feedback which provides the checks and balances is missing, and oddly while sitting here writing this story, the responsibility for this comes close to home. The solution doesn’t lie in changing the politicians, but in changing how they are treated by journalists. Continue reading “The Case For A Technology Aware Lobby Correspondent” →

Virtual Reality With A Dash Of Live Shakespeare

March 27, 2021 by 5 Comments

Virtual reality headsets enforce an isolated experience, cutting us off from people nearby when we put one on our head. But in recent times, when we’re not suppose to have many people nearby anyway, a curious reversal happens: VR can give us a pandemic-safe social experience. Like going to our local community theater, which is an idea [Tender Claws] has been exploring with The Under Presents.

VR hype has drastically cooled, to put it mildly. While some believe the technology is dead and buried, others believe it is merely in a long tough climb out of the Trough of Disillusionment. It is a time for innovators to work without the limelight of unrealistic expectations. What they need is a platform for experiments, evaluate feedback, and iterate. A cycle hackers know well! The Under Presents is such a platform for its corner of VR evolution.

Most VR titles are videogames of one genre or another, so newcomers to the single-player experience may decide its otherworldly exploration feels like Myst. A multi-player option is hardly novel in this day and age, but the relatively scarcity of VR headsets means this world is never going to be as crowded as World of WarCraft. This is not a bug, it is a differentiating feature. Performers occasionally step into this world, changing the experience in ways no NPC ever could. A less crowded world makes these encounters more frequent, and more personal.

Pushing this idea further, there have been scheduled shows where a small audience is led by an actor through a story. As of this writing, a run of a show inspired by Shakespeare’s Tempest is nearing its end. The experience of watching an actor adjusting and reacting to an audience used to be exclusive to an intimate theater production. But with such venues closed, it is now brought to you by VR.

How will these explorations feature in the future of the technology? It’s far too early to say, but every show moves VR storytelling a little bit forward. We hope this group or another will find their way to success and prove the naysayers wrong. But it is also possible this will all go the way of phone VR. We are usually more focused on the technical evolution of VR here, but it’s nice to know people are exploring novel applications of the technology. For one can’t exist for long without the other.

Bespoke Storage Technologies: The Alphabet Soup Found In Modern Hard Drives And Beyond

November 4, 2020 by 70 Comments

It seems like just yesterday (maybe for some of you it was) we were installing Windows 3.1 off floppy drives onto a 256 MB hard drive, but hard drives have since gotten a lot bigger and a lot more complicated, and there are a lot more options than spinning platters.

The explosion of storage options is the result of addressing a variety of niches of use. The typical torrenter downloads a file, which is written once but read many times. For some people a drive is used as a backup that’s stored elsewhere and left unpowered. For others it is a server frequently reading and writing data like logs or swap files. In all cases it’s physics that sets the limits of what storage media can do; if you choose wisely for your use case you’ll get the bet performance.

The jargon in this realm is daunting: superparamagnetic limit, LMR, PMR, CMR, SMR, HAMR, MAMR, EAMR, XAMR, and QLC to name the most common. Let’s take a look at how we got here, and how the past and present of persistent storage have expanded what the word hard drive actually means and what is found under the hood.

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Evaluating Raspberry Pi As A Programmable Logic Controller

August 24, 2020 by 102 Comments

It should be no surprise to many that one can use a Raspbery Pi SBC as an industrial controller, but is it any good at that? That was the question which [Dough Reneker] and [William Shaffer] built a test rig to see how a Raspberry Pi performs in head to head tests. They compared a Python-based control loop on a Raspberry Pi 3B against an C0-12DD1E-2-D AutomationDirect CLICK Programmable Logic Controller (PLC) using a simple water heating example.

A major snag with using the Raspberry Pi as a PLC is the lack of industrial I/O capacity. This requires additional hardware, in this case adding a four-channel ADC board as well as a custom board to condition the signals. The Raspberry Pi looks for 0-3 V inputs where industrial control applications are usually in the -10 to 10 V range and often use a 4-20 mA current loop.

Using a PLC leverages so-called ladder logic, where each action depends on conditions. With each update scan, the PLC ensures that all input conditions are translated into the appropriate output conditions in real-time. It’s only job is to monitor the process at hand and it does this very well.

Here the flexibility and generic nature of the Raspberry Pi running Linux was a disadvantage. Unlike the PLC, the lack of a hard real-time OS means you can’t guarantee the Pi will be as responsive to changing inputs.

The behavior of the two systems showed that while both did the task they were programmed for, the Raspberry Pi was decidedly more erratic. Although one could program around a lot of these issues (presumably using Linux in stripped-down, soft real-time configuration with interrupt-driven native code), the effort needed to make a Raspberry Pi system suitable for an industrial environment shows why single-board computers haven’t seen adoption as replacements for PLCs.

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FreeCAD Vs SolveSpace

July 16, 2020 by 59 Comments

When you are ready to design real things, you’ll find simple CAD programs can be pretty limiting. Serious modern designs tend to use parametric modeling where you don’t necessarily set dimensions and positions of everything but instead constrain the design by describing the relationship between different elements. For example, you can create a vertical line and constrain other lines to be parallel, perpendicular, or form a given angle with that line. There are many tools that can do that, including FreeCAD and SolveSpace, two programs that [Joko Engineeringhelp] uses to create a complex compressor blade and it really shows the differences and similarities between the two tools.

You probably don’t need this particular design, but watching over someone’s shoulder while they do a complex design can be very valuable. Being able to see the differences between the two tools might convince you to learn one or the other or maybe even switch.

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