Updating The Language Of SPI Pin Labels To Remove Casual References To Slavery

June 29, 2020 by 287 Comments

This morning the Open Source Hardware Association (OSHWA) announced a resolution for changing the way SPI (Serial Peripheral Interface) pins are labelled on hardware and in datasheets. The protocol originally included MOSI/MISO references that stand for “Master Out, Slave In” and “Master In, Slave Out”. Some companies and individuals have stopped using these terms over the years, but an effort is being taken up to affect widespread change, lead by Nathan Seidle of Sparkfun.

The new language for SPI pin labeling recommends the use of SDO/SDI (Serial Data Out/In) for single-role hardware, and COPI/CIPO for “Controller Out, Peripheral In” and “Controller In, Peripheral Out” for devices that can be either the controller or the peripheral. The change also updates the “SS” (Slave Select) pin to use “CS” (Chip Select).

SPI is widely used in embedded system design and appears in a huge range of devices, with the pin labels published numerous times in everything from datasheets and application notes to written and video tutorials posted online. Changing the labels removes unnecessary references to slavery without affecting the technology itself. This move makes embedded engineering more inclusive, an ideal that’s easy to get behind.

[2022 Editor’s Note: The OSHWA changed its recommended naming to PICO/POCI for “Peripheral In, Controller Out” and “Peripheral Out, Controller In”. Fine by us! I’ve updated this throughout the rest of the article because it doesn’t change Mike’s original argument at all.]

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Does PHP Have A Future, Or Are Twenty Five Years Enough?

June 29, 2020 by 54 Comments

In June, 1995, Rasmus Lerdorf made an announcement on a Usenet group. You can still read it.

Today, twenty five years on, PHP is about as ubiquitous as it could possibly have become. I’d be willing to bet that for the majority of readers of this article, their first forays into web programming involved PHP.

Announcing the Personal Home Page Tools (PHP Tools) version 1.0.

These tools are a set of small tight cgi binaries written in C.

But no matter what rich history and wide userbase PHP holds, that’s no justification for its use in a landscape that is rapidly evolving. Whilst PHP will inevitably be around for years to come in existing applications, does it have a future in new sites?

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DIY Pocket MP3 Player

June 29, 2020 by 14 Comments

When [Neutrino-1] saw DFRobot’s DFPlayer module, he decided he wanted to make his own retro MP3 player. This tiny module comes packed with a ton of interesting capabilities such as EQ adjustment, volume control, and a 3 watt amplifier amongst other things. It can even play ads in between songs, should you want such a thing.

Controlling the DFPlayer module is easy using serial commands from a microcontroller, making it a convenient subsystem in bigger projects, and a potential alternative to the popular VLSI chips or the hard to come by WT2003S IC. [Neutrino-1] does a good job walking readers through the build making it fairly easy to remix, reuse, and reshare.

With the hardware sorted, all you’ve got to do is flash the firmware and load up an SD card with some MP3s. There’s even a small Python GUI to help you get your new player up and running. [Neutrino-1] also introduces users to the U8g2 display library which he says is a bit more feature-rich than the common Adafruit SSD1306 library. Great job [Neutrino-1]!

While you’re here, take a look at some of our other MP3 projects.

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An Affordable Home Made Vacuum Chamber

June 29, 2020 by 31 Comments

The term “vacuum” means many different things depending whether you are working on space equipment, scientific instruments, or even internal combustion engines. In our sphere it is so often used as a means to draw bubbles out of resin castings, for which it is a relatively easily achievable partial vacuum. It’s something [Fab] is using, in a vacuum chamber made from Plexiglass.

A simple Plexiglass box would collapse under the air pressure on its own, so to mitigate that it’s made from a piece of tube, and with an internal frame of aluminium extrusion with 3D printed joints to strengthen it from the inside. A pressure sensor allows regulation of the pump that drives the vacuum, and connections are made to the chamber using pneumatic hose connectors. It’s not immediately clear how it is sealed, whether there are nay gaskets or other sealant, or whether air pressure pushing the parts together provides enough of a seal.

We’ve featured a lot of vacuum chambers made for this purpose over the years, and we’d be interested to know what vacuum pump is being used here. If  you’re curious too and want to build your own, perhaps you could try a fridge compressor.

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Faux Vintage Radio Gets AirPlay Upgrade

June 28, 2020 by 1 Comment

There’s plenty of vintage-styled hardware out these days, with quality and functionality being mixed at best. [Huan] found such a device in the form of an attractively-styled Bluetooth speaker. Deciding he could improve on the capabilities while retaining a stock look, he got down to hacking.

The aim of the project was to keep the original volume knob, buttons and screen, while replacing the internals with something a bit more capable. A Raspberry Pi Zero was sourced as the brains of the operation, with the Google Voice AIY hardware used as the sound output after early attempts with a discrete amplifier faced hum issues. An Arduino Pro Micro was pressed into service to read the volume encoder along with the buttons and drive the charlieplexed LED screen. Shairport Sync was then installed on the Pi Zero to enable Airplay functionality.

It’s a basic hack that nonetheless gives [Huan] an attractive AirPlay speaker, along with plenty of useful experience working with Arduinos and Raspberry Pis. We’ve seen similar hacks before, too. If you’re working on your own stereo resurrection at home, be sure to drop us a line!

Hantek 3-in-1 Instrument Reviewed

June 28, 2020 by 22 Comments

What kid doesn’t want a Swiss Army knife? Maybe that was the idea behind Hantek’s 3-in-1 instrument that [Rui Santos] reviewed in a recent blog post. You can also watch the video version, below. The instrument is a combination oscilloscope, multimeter, and signal generator. The device is pretty inexpensive and comes in 40 MHz and 70 MHz versions. You can also get versions that drop the function generator if you want to save a little bit more.

The multimeter does 4000 counts and has the usual scales along with capacitance measurements. Rechargeable batteries make it portable, and the signal generator is capable up to 25 MHz. The scope is dual channel, but the sampling drops in half (125 megasamples per second) when using both channels.

The 2.8 inch color screen isn’t as big as your bench scope, but it’s good for a portable device. The review also mentions that there are few buttons so many operations require a lot of menu navigation, but — again — that’s a function of being small. Overall, [Rui] seemed to like the meter well enough. We’ve spent more on a good digital meter, so if this can do that function plus also give you a reasonable scope and signal generator, it seems like a fair deal.

This reminded us of a very polished version of the EM125 we took a look at a few years ago, although that didn’t have a color screen, a second channel, or a signal generator. Of course, signal generators are cheap enough if you want to keep it separate.

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Hackaday Links: June 28, 2020

June 28, 2020 by 8 Comments

You can imagine how stressful life is for high-power CEOs of billion-dollar companies in these trying times; one is tempted to shed a tear for them as they jet around the world and plan their next big move. But now someone has gone and upset the applecart by coming up with a way to track executive private jets as they travel across North America. This may sound trivial, but then you realize that hedge fund managers pay big money for the exact same data in order to get an idea of who is meeting with whom and possibly get an idea of upcoming mergers and acquisitions. It’s also not easy, as the elites go to great lengths to guard their privacy. Luckily, the OpenSky Network lists all ADS-B traffic its web of ground stations receives, unlike other flight monitoring sites which weed out “sensitive” traffic. Python programs scrape the OpenSky API and cross-reference plane registrations with the FAA database to see which company jets are doing what. There are plenty of trips to Aspen and Jackson Hole to filter out, but with everyone and his little brother fancying themselves a day trader lately, it’s another tool in the toolbox.

We got a nice note from Michelle Thompson this week thanking us for mentioning the GNU Radio Conference in last week’s Links article, and in particular for mentioning the virtual CTF challenge that they’re planning. It turns out that Michelle is deeply involved in designing the virtual CTF challenge, after having worked on the IRL challenges at previous conferences. She shared a few details of how the conference team made the decision to go forward with the virtual challenge, inspired in part by the success of the Hack-A-Sat qualifying rounds, which were also held remotely. It sounds like the GNU Radio CTF challenge will be pretty amazing, with IQ files being distributed to participants in lieu of actually setting up receivers. We wish Michelle and the other challenge coordinators the best of luck with the virtual con, and we really hope a Hackaday reader wins.

Amateur radio is often derided as a hobby, earning the epithet “Discord for Boomers” according to my son. There’s more than a grain of truth to that, but there are actually plenty of examples where a ham radio operator has been able to make a big difference in an emergency. Case in point is this story from the Western Massachusetts ARRL. Alden Jones (KC1JWR) was hiking along a section of the Appalachian Trail in southern Vermont last week when he suddenly got light-headed and collapsed. A passing hiker who happened to be an emergency medical technician rendered aid and attempt to contact 911 on his cell phone, but coverage was spotty and the dispatcher couldn’t hear him. So Alden, by this point feeling a little better, pulled out his handy talkie and made an emergency call to the local repeater. Luckily the Western Massachusetts Traffic Net was just about to start, so they went into emergency mode and coordinated the response. One of the hams even went to the rescue staging area and rigged up a quick antenna to improve the signal so that rescuers could finally get a helicopter to give Alden a ride to the hospital. He’s fine now, and hats off to everyone who pitched in on the eight-hour rescue effort.

And finally, there are obviously a lot of details to be worked out before anyone is going to set foot on the Moon again. We’ve got Top People™ working on all the big questions, of course, but apparently NASA needs a little help figuring out how and where the next men and first women on the Moon are going to do their business. The Lunar Loo Challenge seeks innovative designs for toilets that can be used in both microgravity and on the lunar surface. There is $35,000 in prize money for entrants in the Technical division; NASA is also accepting entries in a Junior division, which could prove to be highly entertaining.