[MrRedBeard] wanted to play a particular song from an Arduino program and got tired of trying to hand transcribe the notes. A little research turned up that there was a project to convert Music XML (MXL) files to the Arduino. However, [MrRedBeard] wasn’t a fan of the language it used, so he created his own means of doing the same thing. He learned a lot along the way and was willing to share it in a tutorial that will help you if you want to do the same thing. You can see a video of his results, below.

Of course, MXL files are probably not better than sheet music if you had to create them by hand. Luckily, there’s a large collection of them available online and the song of interest was there. Note that the link in [MrRedBeard’s] post erroneously has the site as a .com instead of a .org, so you’ll want to use the link here instead of there.

A C# application reads the MXL file and converts it for use on the Arduino. There’s also sample code for the Arduino to get you started.

The project that inspired him is on GitHub and uses Ruby if that suits you better. We’ve talked about MXL before, by the way. If you want to integrate multi channel music on the Arduino, you might start here.

When you think of image processing, you probably don’t think of the Arduino. [Jan Gromes] did, though. Using a camera and an Arduino Mega, [Jan] was able to decode input from an Arduino-connected camera into raw image data. We aren’t sure about [Jan’s] use case, but we can think of lots of reasons you might want to know what is hiding inside a compressed JPEG from the camera.

The Mega is key, because–as you might expect–you need plenty of memory to deal with photos. There is also an SD card for auxiliary storage. The camera code is straightforward and saves the image to the SD card. The interesting part is the decoding.

The use case mentioned in the post is sending image data across a potentially lossy communication channel. Because JPEG is compressed in a lossy way, losing some part of a JPEG will likely render it useless. But sending raw image data means that lost or wrong data will just cause visual artifacts (think snow on an old TV screen) and your brain is pretty good at interpreting lossy images like that.

Just to test that theory, we took one of [Joe Kim’s] illustrations, saved it as a JPEG and corrupted just a few bytes in a single spot in it. You can see the before (left) and after (right) picture below. You can make it out, but the effect of just a few bytes in one spot is far-reaching, as you can see.

The code uses a library that returns 16-bit RGB images. The library was meant for displaying images on a screen, but then again it doesn’t really know what you are doing with the results. It isn’t hard to imagine using the data to detect a specific color, find edges in the image, detect motion, and other simple tasks.

Sending the uncompressed image data might be good for error resilience, but it isn’t good for impatient people. At 115,200 baud, [Jan] says it takes about a minute to move a raw picture from the Arduino to a PC.

We’ve seen the Arduino handle a single pixel at a time. Even in color. The Arduino might not be your first choice for an image processing platform, but clearly, you can do some things with it.

If you’ve done 3D printing, you’ve probably at least heard of Tinkercad. This popular CAD package runs in your browser and was rescued from oblivion by Autodesk a few years ago. [Chuck] recently did a video about a new Tinkercad feature: building and simulating virtual Arduino circuits. You can watch it below.

There are a variety of components you can add to your design. You’ll find an integrated code editor and a debugger. You can even get to the serial monitor, all in your browser with no actual Arduino hardware. You can also build simple circuits that don’t use an Arduino, although the component selection is somewhat limited.

This could be great for teaching Arduino in classrooms or when you want to do some development in a hotel room. The layout is very visual, so if you are accustomed to reading schematics, you may not appreciate the style. In addition, the selection of components is somewhat limited (including only supporting the Arduino UNO, as far as we could tell). So for educational purposes, it is great. For breadboarding your next great Arduino-powered robot, maybe not so much.

If you remember Circuits123 (or circuits.io), this is the same underlying technology. They’ve just integrated it with Tinkercad. However, there doesn’t seem to be any real integration between the two other than they are on the same web page now. Perhaps in the future, they’ll let you drop components on the circuit that also show up in the 3D design (or, at least, with sockets or holders for those components).

However, having a simulated Arduino with a debugger could come in handy even if you don’t care about the circuit simulations. If you really want to do circuit simulation, it is hard to go wrong with LTSpice. If you really want it to be in your browser, there’s always Falstad.

If you are working with OBD2 hardware or software, it’s easy enough to access test data, simply plug into a motor vehicle with an OBD2 socket. If, however, you wish to test OBD2 software under all possible fault conditions likely to be experienced by an engine, you are faced with a problem in that it becomes difficult to simulate all faults on a running engine without breaking it. This led [Fixkick] to create an OBD2 simulator using a secondhand Ford ECU supplied with fake sensor data from an Arduino to persuade it that a real engine was connected.

The write-up is quite a dense block of text to wade through, but if you are new to the world of ECU hacking it offers up some interesting nuggets of information. In it there is described how the crankshaft and camshaft sensors were simulated, as well as the mass airflow sensor, throttle position, and speedometer sensors. Some ECU inputs require a zero-crossing signal, something achieved with the use of small isolating transformers. The result is a boxed up unit containing ECU and Arduino, with potentiometers on its front panel to vary the respective sensor inputs.

We’ve brought you quite a few OBD2 projects over the years, for example, there was this LED tachometer, and a way into GM’s OnStar.

Thanks [darkspr1te] for the tip.

An ISP dongle is a very common piece of equipment on a maker’s bench. However, its potential as a hackable device is generally overlooked. The USBASP has an ATmeg8L at its heart and [Robson] decided that this humble USB device could be used as an interface between his PC and a SNES Joypad.

A SNES controller required three pins to communicate with a host: clock, data and latch. In his hack, [Robson]  connects the controller to the ISP interface using a small DIY adaptor and programs the AVR using the V-USB library. V-USB is a software USB library for small microcontrollers and comes in pretty handy in this instance.

[Robson] does a pretty good job of documenting the entire process of creating the interface which includes the USB HID code as well as the SNES joypad serial protocol. His hack works on both Windows and Linux alike and the code is available on GitHub for download.

Simple implementation like this project are a great starting point for anyone looking to dip their toes in the DIY USB device pool. Veterans may find a complete DIY joystick more up their alley and will be inspired by some plastic techniques as well.

If you were sad that Codebender had bit the dust, cheer up. A site called codeanywhere has acquired the online Arduino development environment and brought it back to life. In addition to the main Codebender site, the edu and blocks sites are also back on the air.

Not only is this great news, but it also makes sense. The codeanywhere site is a development IDE in the cloud for many different programming languages. The downside? Well, all the people who said they’d be glad to pay to keep Codebender alive will get a chance to put their money where their mouth is.

Here’s an excerpt from Codebender’s blog:

First of all, codebender will mostly remain the same. It will continue to operate as a standalone service, so you don’t have to change the way you are currently using codebender. However, it will transition to a monthly subscription service. This means that you will be able to use it for free for 1 month (as a trial, beginning on June 1st, or for the first month after registration), and it will then cost $10/month to keep using it. This is the price to pay for keeping codebender alive and sustainable, and it’s a small one, really.

Secondly, Codeanywhere intends to keep adding more and more features, the same way we have been adding features, libraries, and board support in the past few years. So you can expect codebender to keep improving with time, much as it did until now.

We have to wonder how many people will pay $120 / year to do something they can do for free. Mbed has support from ARM and offers a free IDE. Maybe a better deal with Codebender would have been with Atmel or Arduino. Not that we are opposed to charging for services, but we imagine a lot of people will just use free tools unless they have a strong use case for using a cloud-based service.

We covered Codebender’s short-lived demise back in October of last year.

[Ryan Bates] apparently really likes building claw machines. We noticed his latest build with a new PCB, but then we scrolled down and found other incarnations of the machine going back to 2015.

The laser-cut claw is interesting looking and the brains are an Arduino. You can see the action in the video below and there are plenty of older videos on the project page.

Without the PCB, the machine was a mess of wires. With the PCB, a single ribbon cable connects the Arduino to the board, and the board has a layout of screw terminals. This results in a much cleaner layout than before.

You might think you wouldn’t see many homemade claw machines. However, that’s not true. We’ve seen plenty, some of them even using commercial claws. Naturally, some of them also connect to the Internet.

USB chargers are everywhere and it is the responsibility of every hacker to use this commonly available device to its peak potential. [Septillion] and [Hugatry] have come up with a hack to manipulate a USB charger into becoming a variable voltage source. Their project QC2Control works with chargers that employ Quick Charge 2.0 technology which includes wall warts as well as power banks.

Qualcomm’s Quick Charge is designed to deliver up to 24 watts over a micro USB connector so as to reduce the charging time of compatible devices. It requires both the charger as well as the end device to have compatible power management chips so that they may negotiate voltage limiting cycles.

In their project, [Septillion] and [Hugatry] use a 3.3 V Arduino Pro Mini to talk to the charger in question through a small circuit consisting of a few resistors and diodes. The QC2.0 device outputs voltages of 5 V, 9 V and 12 V when it sees predefined voltage levels transmitted over the D+ and D- lines, set by Arduino and voltage dividers. The code provides function calls to simplify the control of the power supply. The video below shows the hack in action.

Quick Charge has been around for a while and you can dig into the details of the inner workings as well as the design of a compatible power supply from reference designs for the TPS61088 (PDF). The patent (PDF) for the Quick Charge technology has a lot more detail for the curious.

Similar techniques have been used in the past and will prove useful for someone looking for a configurable power supply on the move. This is one for the MacGyver fans.

As multitools have lots of different functions in one case, so [Shadwan’s] clock design incorporates a multitude of features. He started the design as a binary clock using a Fibonacci spiral for the shape. However, the finished clock has four modes. The original binary clock, an analog clock, a flashlight (all lights on), and a disco mode that strobes multiple lights.

[Shadwan] used Rhino to model the case and then produced it using a laser cutter. The brains are — small wonder — an Arduino. A 3D-printed bracket holds everything together. You can see the result in the video below.

The clock was a school project and used a Neopixel ring. The students had a 16 position ring, which is not enough to do a 24-hour clock so they settled on a 12-hour design. The LED color, however, changes between AM and PM.

The paper included with the design said that research didn’t turn up any other binary clocks using Neopixels. We found that hard to believe, but it might be true. We certainly didn’t find any in our archives, although there are plenty of non-binary clocks out there.

It used to be hot air soldering gear was exotic, but not anymore. There are plenty of relatively inexpensive choices. Many of these appear to be the same despite having different brand names and model numbers. One that is common and inexpensive is the 858D. These run about $50. [Gabse] has one and decided to upgrade it using some open source controller hardware and software. There wasn’t a complete guide, so he created one himself.

According to the original GitHub page, the controller will work with the Youyue-858D and any clones. However, there are others like the Atten 858D that use a different controller. In addition, there have been several variants. [Gabse’s] guide is for the latest version. Information on other versions and brands might be on this discussion board thread.

The new controller and firmware offer better temperature regulation, a safety feature that prevents the handpiece from heating up if power is applied when the handpiece is not docked, fan fault detection, a cold air mode, a sleep mode, and more. There are PCBs available from OSH Park if you want to attempt it yourself. There are also a few YouTube videos showing the custom firmware, one of which appears below.

In addition to the controller change, [Gabse] shows you some optional tweaks to make the handpiece more robust, change the power plug, and make the cradle sensor more reliable. Worthwhile changes and all well-suited for the processing power of the Arduino.

We have gotten used to having the handpiece fixed on the bench, that’s another easy hack. You can also try an unholy union of soldering iron and articulated lamp.