A Simple Route To A Plug Top Pi

There are a host of tiny plug-top computers available for the experimenter who requires an all-in-one mains-powered computing platform without the annoyance of a full-sized PC or similar. But among the various models there has always been something missing, a plug-top Raspberry Pi. To address that gap in the market, [N-O-D-E] has created a fusion of Pi and plug using the official Raspberry Pi PSU accessory and a Raspberry Pi Zero, with a UUGear Zero4U USB hub sandwiched between the two.

It’s a pretty straightforward and simple build, the back of the PSU is formed into a flat surface with a bit of Sugru, then the power cable is stripped back to its wires which are then connected to the power pins on the USB hub. The hub is then attached to the Sugru — he doesn’t say how, but we suspect double-sided tape — and the Pi is mounted on top of the hub. Pogo pins make the required connections to the pads on the underside of the computer, so it can be removed and replaced at will.

The result is a useful addition to your Pi arsenal, one that could be used for a host of little stand-alone devices. It could use a cover, however we suspect a 3D printer owner could create themselves one with relative ease. The full description is shown in the video below the break.

Continue reading “A Simple Route To A Plug Top Pi”

Blob-less Raspberry Pi Linux Is A Step Closer

The Raspberry Pi single board computer has been an astounding success since its launch nearly five years ago, to the extent that as of last autumn it had sold ten million units with no sign of sales abating. It has delivered an extremely affordable and pretty powerful computer into the hands of hobbyists, youngsters, hackers, engineers and thousands of other groups, and its open-source Raspbian operating system has brought a useful Linux environment to places we might once have thought impossible.

The previous paragraph, we have to admit, is almost true. The Pi has sold a lot, it’s really useful and lots of people use it, but is Raspbian open-source? Not strictly. Because the Broadcom silicon that powers the Pi has a significant amount of proprietary tech that the chipmaker has been unwilling to let us peer too closely at, each and every Raspberry Pi operating system has shipped with a precompiled binary blob containing the proprietary Broadcom code, and of course that’s the bit that isn’t open source. It hasn’t been a problem for most Pi users as it’s understood to be part of the trade-off that enabled the board’s creators to bring it to us at an affordable price back in 2012, but for open-source purists it’s been something of a thorn in the side of the little board from Cambridge.

This is not to say that all is lost on the blob-free Pi front. Aided by a partial pulling back of the curtain of secrecy by Broadcom in 2014, work has quietly been progressing, and we now have the announcement from [Kristina Brooks] that a minimal Linux kernel can boot from her latest open firmware efforts. You won’t be booting a blob-free Raspbian any time soon as there are bugs to fix and USB, DMA, and video hardware has still to receive full support, but it’s a significant step. We won’t pretend to be Broadcom firmware gurus as we’re simply reporting the work, but if it’s your specialty you can find the code in its GitHub repository. Meanwhile, we look forward to future progress on this very interesting project.

We reported on the partial Broadcom release back in 2014. At the time, the Raspberry Pi people offered a prize to the first person running a native Quake III game on their hardware, sadly though they note the competition is closed they haven’t linked to the winning entry.

Raspberry Pi Home Automation for the Holidays

When you want to play around with a new technology, do you jump straight to production machinery? Nope. Nothing beats a simplified model as proof of concept. And the only thing better than a good proof of concept is an amusing proof of concept. In that spirit [Eric Tsai], alias [electronichamsters], built the world’s most complicated electronic gingerbread house this Christmas, because a home-automated gingerbread house is still simpler than a home-automated home.

fya59blixaq00y3-largeYeah, there are blinky lights and it’s all controlled by his smartphone. That’s just the basics. The crux of the demo, however, is the Bluetooth-to-MQTT gateway that he built along the way. A Raspberry Pi with a BTLE radio receives local data from BTLE sensors and pushes them off to an MQTT server, where they can in principle be read from anywhere in the world. If you’ve tried to network battery-powered ESP8266 nodes, you know that battery life is the Achilles heel. Swapping over to BTLE for the radio layer makes a lot of sense.

Continue reading “Raspberry Pi Home Automation for the Holidays”

Portable RetroPie Builds on the Shoulders of Giants

For anyone wanting to get that shot of nostalgia without the hassle of finding an NES Classic, the Retropie project is a great starting point. Of course, it’s not too noteworthy to grab a Raspberry Pi, throw a pre-built distribution on it, and plug in an SNES to USB converter. What is noteworthy, however, is building a Retropie that’s portable and that has the quality and polish of the latest build from [fancymenofcornwood].

render-blowup-of-retropieFor starters, the laser cut wood case was custom-made. From there, all of the PCBs were fitted including specific ones to handle each set of buttons (complete sets of D-pads, shoulder buttons, and joysticks) and another for the 5″ HDMI screen. It has stereo speakers and its own headphone jack (to the envy of all new iPhone owners), and is powered from a Raspberry Pi 2 running Retropie 4.1. The battery pack shouldn’t leave you stranded, either, especially not if you grew up playing the Sega Game Gear.

The quality of the build here is outstanding, and its creator made a design choice to make it easily replicable, so if you’ve wanted to play N64 or PS1 games while on the go, this might be what you’ve been waiting for. There are lots of other options for getting some fun from a Retropie going though, from building one into a coffee table to re-purposing that infamous Game Gear.

Obligatory clip of this portable playing Doom is found after the break.

Continue reading “Portable RetroPie Builds on the Shoulders of Giants”

Give Your Raspberry Pi A Good Hammering

One of the features of the Raspberry Pi Zero is that it arrives with no GPIO header pins installed. The missing pins reduce the price of the little computer, as well as its shipping volume. A task facing most new Pi Zero owners has therefore been to solder a set of pins into the holes, and indeed many suppliers will sell you the pins alongside your new Zero.

The British Pi accessories supplier Pimoroni think they may have a solution to this problem, with a set of solderless pins that the user is expected to fit by tapping both pins and Pi with a hammer. Each pin is designed to deform under pressure, and grip the through-plated walls of the hole in the PCB. In reality they are push-fit pins designed to be fitted with a press or a special tool, but since the average Zero buyer will have neither they supply a small laser-cut jig and give instructions to tap carefully with a pin hammer or similar. They have a demonstration as part of their regular Bilge Tank podcast, which we’ve included below the break.

Pins like these can be quite reliable when installed with the proper tools. They are often used in military and aerospace systems. In this case though, we expect that a chorus of you will be limbering up to comment that it would be far better to solder the connector, and we can’t help agreeing with you. Of course this product isn’t really marketed at Hackaday readers. Instead, the target market of a board like the Zero are children. For them soldering may well be a step too far. We can’t help wondering though whether hammer installation will deliver a reliable enough contact, and whether we’ll see a horde of youngsters whose Pi HATs don’t work due to dodgy connectors. Aside from the ones who’ve broken their Zeros with hammering that was a bit enthusiastic, that is.

Continue reading “Give Your Raspberry Pi A Good Hammering”

Air Conditioner Speaks Serial, Just Like Everything Else

Like so many other home appliances, it’s likely that even your air conditioner has a serial interface buried inside it. If you’re wondering why, it’s because virtually every microcontroller on the planet has a UART built in, and it’s highly useful for debugging during the development process, so it makes sense to use it. Thus, it was only a matter of time before we saw a hacked airconditioner controlled by a Raspberry Pi.

[Hadley] was growing frustrated with the IR remote for his Mitsubishi air conditioner; it can issue commands, but it’s a one way interface – there’s no feedback on current status or whether commands are received, other then the occasional beep or two. Deciding there had to be a better way, [Hadley] grabbed a Saleae Logic Analyser and started probing around, determining that the unit spoke 5 V TTL at 2400 bps with even parity. The next step was to start talking back.

Continue reading “Air Conditioner Speaks Serial, Just Like Everything Else”

Alexa Robot Coffee Maker Brews Coffee, Speaks For Itself

To keep hackers fueled and hacking, why not hack a coffee maker into a coffee brewing robot? [Carter Hurd] and [David Frank] did just that at The Ohio State’s Hack OHI/O 24 hour Hackathon. They even won the “Best Hardware Hack”. The video below shows it in action but the guys sent us some extra details on how it’s made.

To give it a voice they put Alexa on a Raspberry Pi. Using an audio splitter they have the voice go both to a speaker and to an Arduino. The Arduino then uses the amplitude of the audio signal’s positive values to determine how much to open the “mouth”, the coffee maker’s hinged cover. As is usually the case, there’s some lag, but the result is still quite good.

The brewing is also controlled by the Arduino. They plan to add voice control so that they can simply ask, “Alexa, make me coffee”, but for now they added a switch on the side to start the brewing. That switch tells the Arduino to work one servo to open the cover, another to insert a coffee filter, and two more to scoop up some coffee from a container and dump it into the filter.

They replaced the coffee maker’s on/off switch with a relay so that after the Arduino closes the cover again, it uses the relay to start the brewing. The result is surprisingly human-like. We especially like the graceful movement achieved by the two servos for scooping up and dumping the coffee. Full disclosure: they did admit that it would often either not scoop enough coffee or scoop enough but spill a bunch on the group.

Continue reading “Alexa Robot Coffee Maker Brews Coffee, Speaks For Itself”