Make Room For A New Arduino Competitor – With Native Brainf*ck!

January 12, 2021 by Jenny List 70 Comments

With so many smaller and more capable microcontroller boards on the market it’s now fairly safe to say that the classic Arduino footprint and form factor is rather outdated. That’s not to say that there’s no fight left in the old contender though, and to prove it here’s a new platform in the familiar style set by the venerable Atmel-based board. [Eduardo Corpeño]’s Brainfuino is an Arduino competitor that runs everyone’s favourite esoteric programming language, Brainf*ck. (Keeping it SFW, folks.)

And in case you mistake it for a Brainf*ck emulator on a PCB then stand ready to be corrected, for this board runs the language natively in a Brainf*ck softcore on a Lattice MachXO2 FPGA. This is the real deal, on which only a true genius or masochist would dare to code.

The board itself is very neatly executed with a graphical style that presents more than a nod to the original Arduino. On this board is the FPGA, 256 kB ROM and 138 kB RAM, an STM32 to provide a USB serial port and an analogue input, and a level shifter to provide Arduino-style 5 V logic on the pins. We can see it’ll provide hours of fun to anyone interested in learning Brainf*ck, but besides that it has potential as an Arduino-shaped FPGA board. We like the joke, we like the graphical and engineering design, but underneath that lies quite the technical achievement.

Brainf*ck has made it to Hackaday before, not least in this jaw-dropping relay computer.

Custom Controller Makes Turbomolecular Pump Suck

January 6, 2021 by Anool Mahidharia 16 Comments

[Mark Aren] purchased a pair of Turbomolecular pumps (TMP) sans controllers, and then built an FPGA based BLDC controller for the Turbomolecular pumps. A TMP is similar to a jet turbine, consisting of several stages of alternating moving turbine blades and stationary stator blades, and having turbine rotation speeds ranging from 10,000 rpm to 90,000 rpm. TMP’s cannot exhaust directly to atmosphere, and must be combined with a backing (or roughing) pump to create a lower grade vacuum first. They find use in lots of applications such as electron microscopy, analytical sciences, semiconductors and lamp manufacturing. With the lamp industry rapidly embracing LEDs, many of the traditional lamp making lines are getting decommissioned, and if you are lucky, you can snag a TMP at a low cost – but it still will not be cheap by any means.

The two BOC-Edwards EXT255H Compound Molecular Pumps (PDF), that [Mark] bought did not have their accompanying EXC100E Turbomolecular Pump Controllers (PDF), and given pandemic related restrictions, he decided to build a controller of his own, using components and modules from his parts bin. The pump and controller user manuals offered only sketchy details about the sensored BLDC motor used in the pump. The low phase-to-phase resistance implied low drive voltage, and [Mark] decided to try running it at 24 V to start with. He already had experience using the Mitsubishi PS21245-E IGBT inverter bridge, and even though it was rated for much higher voltages, he knew that it would work just fine at 24 V too.

After figuring out a state machine for motor commutation that utilized PWM based adjustable current control, he implemented it on a 128 element FPGA board. Considering how expensive the TMP was, he wisely decided to first try out his driver on a smaller “expendable” BLDC motor. This whole process was non-trivial, since his available IGBT module was untested and undocumented, and required several tweaks before he could run it at the required 12 kHz PWM signals. His test motor was also undocumented, failing to run correctly when first hooked up. Fixing that issue meant having to disassemble the motor to check its internal wiring. Eventually, his efforts paid off, and he was able to safely run the TMP motor to confirm that his design worked.

With FPGA code, IGBT wiring and power supply issues sorted, the next step was to add a supervisory micro-controller, using an Arduino Nano. Its functions included interfacing with a touch screen LCD as a user interface, communicating with the FPGA module, and controlling several relays to switch power to the motor power supply, the roughing pump, TMP cooling fan, and a solenoid for the vacuum vent. Spindle current is calculated by measuring voltage drop across shunt resistors on the low side of the IGBT. Motor speed is measured using one of the motor hall sensors, and a thermistor provides motor temperature sensing. [Mark]’s PCB fabrication technique seems a bit different too. Using an Excellon drill file, he drills holes in a piece of plastic using a laser cutter to create a bare board, and then solders copper tracks by hand.

His initial tests at atmospheric pressure (although not recommended unless you monitor pump temperature), resulted in 7300 rpm while consuming about 7 Amps before he had to shut it down. In further tests, after adding a roughing pump to the test setup, he was able to spin the TMP to 20,000 rpm while it consumed 0.6 A. Obviously, the pump is rated to operate at a higher voltage, possibly 48 V based on the values mentioned in the TMP controller manual. The project is still “work in progress” as [Mark] hopes to eventually drive the pump up to its specified 60,000 rpm operating speed. What is not clear is what he eventually intends to do with this piece of exotic machinery. All he mentions is that “he has recently taken an interest in high-vacuum systems and is interested in exploring the high-vacuum world of electron guns.”

Maybe [Mark] can compare notes with the Open Source Turbomolecular Pump Controller that we featured some time back. And if you’d like to be a little bit more adventurous and build you own TMP, we got you covered with this DIY Everyman’s Turbomolecular Pump.

2020: As The Hardware World Turns

December 29, 2020 by Tom Nardi 13 Comments

By pretty much any metric you care to use, 2020 has been an unforgettable year. Usually that would be a positive thing, but this time around it’s a bit more complicated. The global pandemic, unprecedented in modern times, impacted the way we work, learn, and gather. Some will look back on their time in lockdown as productive, if a bit lonely. Other’s have had their entire way of life uprooted, with no indication as to when or if things will ever return to normal. Whatever “normal” is at this point.

But even in the face of such adversity, there have been bright spots for our community. With traditional gatherings out of the question, many long-running tech conferences moved over to a virtual format that allowed a larger and more diverse array of presenters and attendees than would have been possible in the past. We also saw hackers and makers all over the planet devote their skills and tools to the production of personal protective equipment (PPE). In a turn of events few could have predicted, the 2020 COVID-19 pandemic helped demonstrate the validity of hyperlocal manufacturing in a way that’s never happened before.

For better or for worse, most of us will associate 2020 with COVID-19 for the rest of our lives. Really, how could we not? But over these last twelve months we’ve borne witness to plenty of stories that are just as deserving of a spot in our collective memories. As we approach the twilight hours of this most ponderous year, let’s take a look back at some of the most interesting themes that touched our little corner of the tech world this year.

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Edge-Mounted LEDs Make This Spherical POV Look Fantastic

December 18, 2020 by Dan Maloney 19 Comments

For as many of them as we’ve seen, we still love a good persistence of vision display project. There’s something fascinating about the combination of movement and light creating the illusion of solid surfaces, and there’s always fun to be had in electromechanical aspects of a POV build. This high-resolution spherical POV display pushes all those buttons, and more.

Called “Flicker” for obvious reasons by its creator [Dan Foisy], this POV display started with a pretty clear set of goals in terms of resolution and image quality, plus the need to support animated images, all in a spherical form factor. These goals dictated the final form of the display — a PCB disc spinning vertically. The shaft has the usual slip rings for power distribution and encoders for position feedback. The PCB, though, is where the interesting stuff is.

[Dan] chose to use an FPGA to slice and dice the images, which are fed from a Raspberry Pi’s HDMI port, to the LED drivers. And the LEDs themselves are pretty slick — he found parts with 1.6 mm lead spacing, making them a perfect fit for mounting on the rim of the PCB rather than on either side. A KiCAD script automated the process of laying out the 256 LEDs and their supporting components as evenly as possible, to avoid imbalance issues.

The video below shows Flicker in action — there are a few problem pixels, but on the whole, the display is pretty stunning. We’ve seen a few other spherical POV displays before, but none that look as good as this one does.

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A Xilinx Zynq Linux FPGA Board For Under $20? The Windfall Of Decommissioned Crypto Mining

December 10, 2020 by Jenny List 80 Comments

One of the exciting trends in hardware availability is the inexorable move of FPGA boards and modules towards affordability. What was once an eye-watering price is now merely an expensive one, and no doubt in years to come will become a commodity. There’s still an affordability gap at the bottom of the market though, so spotting sub-$20 Xilinx Zynq boards on AliExpress that combine a Linux-capable ARM core and an FPGA on the same silicon is definitely something of great interest. A hackerspace community friend of mine ordered one, and yesterday it arrived in the usual anonymous package from China.

There’s a Catch, But It’s Only A Small One

The heftier of the two boards, in all its glory.

There are two boards to be found for sale, one featuring the Zynq 7000 and the other the 7010, which the Xilinx product selector tells us both have the same ARM Cortex A9 cores and Artix-7 FPGA tech on board. The 7000 includes a single core with 23k logic cells, and there’s a dual-core with 28k on the 7010. It was the latter that my friend had ordered.

So there’s the good news, but there has to be a catch, right? True, but it’s not an insurmountable one. These aren’t new products, instead they’re the controller boards for an older generation of AntMiner cryptocurrency mining rigs. The components have 2017 date codes, so they’ve spent the last three years hooked up to a brace of ASIC or GPU boards in a mining data centre somewhere. The ever-changing pace of cryptocurrency tech means that they’re now redundant, and we’re the lucky beneficiaries via the surplus market.

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Pushing The FPGA Video Player Further

November 30, 2020 by Matthew Carlson 4 Comments

A fact universally known among the Hackaday community is that projects are never truly done. You can always spin another board release to fix a silkscreen mistake, get that extra little boost of performance, or finally spend the time to track down that weird transient bug. Or in [ultraembedded’s] case, take a custom FPGA player from 800 x 600 to 1280 x 720. The hardware used is a Digilent Arty A7 and PMOD boards for I2S2, VGA, and MicroSD. We previously covered this project back when it was first getting started.

Getting from 800 x 600 to 1280 x 720 — 31% more pixels — required implementing a higher performance JPEG decoder that can read in the MPJEG frames, pushing out a pixel every 2.1 clock cycles. The improvements also include a few convenience features such as an IR remote. The number of submodules inside the system is just incredible, with most of them being implemented or tweaked by [ultraembedded] himself.

For the FPGA Verilog, there’s the SD/MMC interface, the JPEG decoder, the audio controller, the DVI framebuffer, a peripheral core, and a custom RISC-V CPU. For the firmware loaded off the SD card, it uses a custom RTOS running an MP3 decoder, a FAT32 interface, an IR decoder, and a UI based on LVGL.

We think this project represents a wonderful culmination of all the different IP cores that [ultraembedded] has produced over the years. All the code for the FPGA media player is available on GitHub.

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Taking Over The Amazing Control Panel Of A Vintage Video Switcher

November 28, 2020 by Mike Szczys 15 Comments

Where does he get such wonderful toys? [Glenn] snagged parts of a Grass Valley Kalypso 4-M/E video ~~mixer~~ switcher control surface from eBay and since been reverse engineering the button and display modules to bend them to his will. The hardware dates back to the turn of the century and the two modules would have been laid out with up to a few dozen others to complete a video ~~mixing~~ switcher console.

[Glenn’s] previous adventures delved into a strip of ten backlit buttons and gives us a close look at each of the keyswitches and the technique he used to pull together his own pinout and schematic of that strip. But things get a lot hairier this time around. The long strip seen above is a “machine control plane” module and includes a dozen addressible character displays, driven by a combination of microcontrollers and FPGAs. The square panel is a “Crosspoint Switch Matrix” module include eight individual 32 x 32 LCDs drive by three dedicated ICs that can display in red, green, or amber.

[Glen] used an STM8 Nucleo 64 to interface with the panels and wrote a bit of code to help map out what each pin on each machine control plane connector might do. He was able to stream out some packets from the plane that changed as he pressed buttons, and ended up feeding back a brute-force of that packet format to figure out the LED display protocols.

But the LCDs on the crosspoint switch were a more difficult nut to crack. He ended up going back to the original source of the equipment (eBay) to get a working control unit that he could sniff. He laid out a man-in-the-middle board that has a connector on either side with a pin header in the middle for his logic analyzer. As with most LCDs, the secret sauce was the initialization sequence — an almost impossible thing to brute force, yet exceedingly simple to sniff when you have a working system. So far he has them running under USB control, and if you are lucky enough to have some of this gear in your parts box, [Glen] has painstakingly recorded all of the details you need to get them up and running.