Hackaday Links: January 21, 2018

You know what next week is? Sparklecon! What is it? Everybody hangs out at the 23b Hackerspace in Fullerton, California. Last year, people were transmuting the elements, playing Hammer Jenga, roasting marshmallows over hot resistors, and generally having a really great time. It’s the party for our sort of people, and there are talks on 3D projection mapping and a hebocon. I can’t recommend this one enough.

The STM32F7 is a very, very powerful ARM Cortex-M7 microcontroller with piles of RAM, oodles of Flash, DSP, and tons of I/O. It’s a relatively new part, so are there any breakout or dev boards for it? Sure thing. [satsha] used a desktop CNC mill to create what is probably the simplest possible breakout board for the STM32F7. There’s not much here — just some parts for power and a few LEDs — but this is all you need to get one of these powerful chips up and running.

It’s cold and dark and you can’t fly RC airplanes in January. It’s not because planes and quadcopters don’t work in the cold (they should work better, but I’d love to see a graph of battery temperature and density altitude), it’s that your hands don’t work in the cold. What’s the solution? Just strap some motorcycle handwarmer thingies onto your transmitter. With a 2200 battery strapped to the back, you’ll get about an hour of runtime for these handwarmers.

The BBC is reporting the latest advancement in Hyperloop technology. Is it a fundamentally different way of digging tunnels that isn’t simply scaling down the size of tunnel boring machines? No. Is it improvements in material science that would allow the seals on a 500-mile-long steel pressure chamber to exist? No. Does this latest advancement mitigate the ‘hillbillies with guns’ problem that would turn every Hyperloop car into a literal bullet screaming towards one of the most spectacular deaths possible? No. The chief executive of the Virgin Hyperloop project has something better in mind. A smartphone app, “that would connect future Hyperloop passengers with other modes of transport on arrival.”

Virtual Analog Synth Brings Tunes To The Masses

Part of the problem with getting involved in a new hobby is the cost. Whether you’re learning to surf, weld, garden, or program, often the entry cost is several hundred dollars. We’re huge fans of things with low barriers to entry, though, so we were happy to see the latest project from [pappas.chris] which promises to introduce newcomers to the musical hobby of synthesizers for just over $20.

The build revolves around an STM32F7 microcontroller and offers a 6-voice virtual analog synthesizer. The build is expandable, too, so if you want to build on the STM platform with any other add ons the process is relatively simple. This might not be necessary for a while, though; the current iteration offers many features that a typical synthesizer would have. Exhausting the possibilities with this tiny device will take some effort.

Since the synth is built on a common microcontroller platform, it’s easily programmable too, which isn’t often a feature of commercial synthesizers. You can listen to a sample audio file on the project page, and get started building your own as well. If you don’t have your own keyboard to use with it, there are other DIY synths that cover that area as well.

Hackaday Links: May Day, 2016

Humble Bundle is a great way to fill up your Steam library – just pay what you want, and get some indie video games. The Humble Bundle is much more than video games, because No Starch Press just put up a bundle of books on hacking. No, there are no books about wearing balaclavas and using laptops with one hand. I haven’t written that book yet. There’s some choice books in this bundle, including [Bunnie]’s Hacking the XboxAutomate the Boring Stuff with Python, and Practical Malware Analysis.

The Raspberry Pi camera – the $25 add-on webcam that plugs directly into the Pi – is getting an upgrade. The original camera was a five Megapixel sensor that was EOL’d at the end of 2014. The Raspberry Pi foundation bought up a lot of stock, but eventually there would be a replacement. The new sensor is a Sony IMX219 eight Megapixel deal, available at the same price. We assume a NoIR version without the IR filter will be released shortly.

Here’s a little hardware review that doesn’t quite merit a full post. The Raspberry Pi Zero is great, and will be even better once production ramps up again and stock lands in warehouses. One problem with the Zero is the lack of USB ports, leading to at least two Hackaday posts with the exact same headline, ‘Yet Another Pi Zero USB Hub‘. Obviously, there’s a market for an easy to use USB hub for the Zero, and this company is stepping up to fill the need. The killer feature here is the use of pogo pins to tap into the USB differential lines, power and ground pads on the bottom of the Pi Zero. The USB hub is based on the popular FE 1.1 4-port USB hub controller, giving the Pi Zero four USB 2.0 ports. Does it work? Yeah, and it’s only $10. A pretty neat little device that will be very useful when Pi Zeros flood workbenches the world over.

It was announced in 2014, released in 2015, but the STM32F7 hasn’t seen a lot of action around these parts. A shame, because this is the upgrade to the famously powerful STM32F4 microcontroller that’s already capable of driving high-resolution displays through VGA, being an engine control unit for a 96 Ford Aspire, and being a very complex brushless motor driver. The STM32F7 can do all of these and more, and now ST is cutting prices on the F7’s Discovery Board. If you’re looking for a high-power ARM micro and don’t need to run Linux, you won’t do better elsewhere.

Need to reflow a board, but don’t have a toaster oven? Use a blowtorch! By holding a MAPP blowtorch a foot away from a board, [whitequark] was able to successfully reflow a large buck converter. There’s a lot of water vapor that will condense on the board, so a good cleaning afterward is a good idea.

A few weeks ago, [Mr. LeMieux] built a 360 degree, all-metal hinge. He’s been up to something a little more dangerous since then: building piles of mini table saws. Small table saws are useful for miniatures, models, and the like. [Mr. LeMieux]’s table saw is a piece of CNC’d aluminum, with a bearing and saw arbor that attaches to an electric drill. Dangerous, you say? Not compared to the competition. Behold the worst forty dollars I’ve ever spent. This Horror Freight mini table saw is by far the worst tool I’ve ever used. The bed was caked with streaky layers of paint, uneven, the blade wasn’t set at 90 degrees, and the whole thing was horrifically underpowered. Trust me when I say the CNC electric drill version is safer.

New Part Day: STM32F7, An ARM Cortex-M7

It was announced last year, but ST is finally rolling out the STM32F7, the first microcontroller in production that is based on the ARM Cortex-M7.

The previous go-to part from the ST catalog was the STM32F4, an extremely powerful chip based on the ARM Cortex M4 processor. This chip was incredibly powerful in its time, and is still a respectable choice for any application that needs a lot of horsepower, but not a complete Linux system. We’ve seen the ~F4 chip pump out 800×600 VGA, drive a thermal imaging camera, and put OpenCV inside a webcam. Now there’s a new, even more powerful part on the market, and the mind reels thinking what might be possible.

Right now there a few STM32F7 parts out, both with speeds up to 216MHz, Flash between 512k and 1MB, and 320kB of RAM. Peripherals include Ethernet, USB OTG, SPDIF support, and I²S. The most advanced chip in the line includes a TFT LCD controller, and a crypto processor on-chip. All of the chips in the STM32F7 line are pin compatible with the STM32F4 line, with BGA and QFP packages available.

As with the introduction of all of ST’s microcontrollers, they’re rolling out a new Discovery board with this launch. It features Ethernet, a bunch of audio peripherals, USB OTG, apparently an Arduino-style pin layout, and a 4.3 inch, 480×272 pixel LCD with capacitive touch. When this is available through the normal distributors, it will sell for around $50. The chips themselves are already available from some of the usual distributors, for $17 to $20 in quantity one. That’s a chunk of change for a microcontroller, but the possibilities for what this can do are really only limited by an engineer’s imagination.