Motion-Controlled KVM Switch

Once upon a time, [hardwarecoder] acquired a Gen8 HP microserver that he began to toy around with. It started with ‘trying out’ some visualization before spiraling off the rails and fully setting up FreeBSD with ZFS as a QEMU-KVM virtual machine. While wondering what to do next, he happened to be lamenting how he couldn’t also fit his laptop on his desk, so he built himself a slick, motion-sensing KVM switch to solve his space problem.

At its heart, this device injects DCC code via the I2C pins on his monitors’ VGA cables to swap inputs while a relay ‘replugs’ the keyboard and mouse from the server to the laptop — and vice-versa — at the same time. On the completely custom PCB are a pair of infrared diodes and a receiver that detects Jedi-like hand waves which activate the swap. It’s a little more complex than some methods, but arguably much cooler.

Using an adapter, the pcb plugs into his keyboard, and the monitor data connections and keyboard/mouse output to the laptop and server stream out from there. There is a slight potential issue with cables torquing on the PCB, but with it being so conveniently close, [hardwarecoder] doesn’t need to handle it much.

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Sound Isolated Server Rack

Servers are most often found in climate controlled data centers. This means they aren’t exactly built for creature comforts like quiet operation. Quite the contrary — many server chassis include fans which absolutely scream when the machine is under load. [Whiskykilo] needed to set up a 12 U rack in his basement for working from home. He knew the sound would get on anyone’s nerves, but especially on those of his wife.

To solve this problem, he built a sound isolated rack. The build started with a standard 12 U metal rack frame. This is wrapped in 1/2″ MDF coated with automotive sound deadening material. An outer frame built of 1×4 lumber and another layer of 1/2″ MDF. Isolating the inner and outer boxes made the biggest contribution to quieting down the noisy servers.

Computers need to breathe, so the front and back doors of the rack enclosure include banks of intake and exhaust fans to keep air flowing through the servers. Two AC Infinity controllers keep the fans operating and monitor temperature. These machines do generate some heat – so 64 °F (18C) intake and 81 °F (27C) exhaust is not unheard of. The servers don’t seem to mind running at these temperatures. A Raspberry Pi 3 keeps an eye on UPS operation and displays the data on a 7″ HDMI LCD.

Interested in running a server at home? You don’t have to go to the lumberyard – check out this server made with Ikea components, or this server built from 96 MacBook Pros.

Hackaday Prize Entry: Minimalist HTTP

For his Hackaday Prize entry, [Yann] is building something that isn’t hardware, but it’s still fascinating. He’s come up with a minimalist HTTP compliant server written in C. It’s small, it’s portable, and in some cases, it will be a bunch better solution than throwing a full Linux stack into a single sensor.

This micro HTTP server has two core modules, each with a specific purpose. The file server does exactly what it says on the tin, but the HTTaP is a bit more interesting. HTTaP is a protocol first published in 2014 that is designed to be a simpler alternative to WebSockets.

[Yann] has been experimenting with HTTaP, and the benefits are obvious. You don’t need Apache to make use of it, HTTaP can work directly with an HTML/JavaScript page, and using only GET and POST messages, you can control hardware and logic circuits.

As this is a minimalist HTTP server, the security is dubious at best. That’s not the point, though. This is just a tool designed for use in a lab or controlled environments with an air gap. Safety, scheduling, encryption, and authentication are not part of HTTaP or this micro HTTP server.

The Silence of the Fans

The good thing about using a server-grade machine as your desktop is having raw computing power at your fingertips. The downside is living next to a machine that sounds like a fleet of quadcopters taking off. Luckily, loud server fans can be replaced with quieter units if you know what you’re doing.

Servers are a breed apart from desktop-grade machines, and are designed around the fact that they’ll be installed in some kind of controlled environment. [Juan] made his Dell PowerEdge T710 tower server a better neighbor by probing the PWM signals to and from the stock Dell fans; he found that the motherboard is happy to just receive a fixed PWM signal that indicates the fans are running at top speed. Knowing this, [Juan] was able to spoof the feedback signal with an ATtiny85 and a single line of code. The noisy fans could then be swapped for desktop-grade fans; even running full-tilt, the new fans are quieter by far and still keep things cool inside.

But what to do with all those extra fans? Why not team them up with some lasers for a musical light show?

IOT Startup Bricks Customers Garage Door Intentionally

Internet of Things startup Garadget remotely bricked an unhappy customer’s WiFi garage door for giving a bad Amazon review and being rude to company reps. Garadget device owner [Robert Martin] found out the hard way how quickly the device can turn a door into a wall. After leaving a negative Amazon review, and starting a thread on Garadget’s support forum complaining the device didn’t work with his iPhone, Martin was banned from the forum until December 27, 2019 for his choice of words and was told his comments and bad Amazon review had convinced Garadget staff to ban his device from their servers.

The response was not what you would expect a community-funded startup. “Technically there is no bricking, though,” the rep replied. “No changes are made to the hardware or the firmware of the device, just denied use of company servers.” Tell that to [Robert] who can’t get into his garage.

This caused some discontent amoung other customers wondering if it was just a matter of time before more paying customers are subjected to this outlandish treatment. The Register asked Garadget’s founder [Denis Grisak] about the situation, his response is quoted below.

 It was a Bad PR Move, Martin has now had his server connection restored, and the IOT upstart has posted a public statement on the matter.– Garadget

This whole debacle brings us to the conclusion that the IoT boom has a lot of issues ahead that need to be straightened out especially when it comes to ethics and security. It’s bad enough to have to deal with the vagaries of IoT Security and companies who shut down their products because they’re just not making enough money. Now we have to worry about using “cloud” services because the people who own the little fluffy computers could just be jerks.

Bench Power Supply Uses Server Voltage Regulator

If you stuff a computer into a rack with a bunch of other machines, you’d better make it a tough machine. Server-grade means something, so using server parts in a project, like this high-wattage power supply using server voltage regulators, can take it to the next level of robustness.

But before [Andy Brown] could build this power supply, he had to reverse-engineer the modules. Based on what he learned, and armed with a data sheet for the modules, he designed a controller to take advantage of all the capabilities of them and ended up with a full-featured power supply. The modules are rated for 66 watts total dissipation at 3.3 volts and have a secondary 5-volt output. Using an ATmega328, [Andy] was able to control the module, provide a display for voltage and current, temperature sensing and fan control, and even a UART to allow data logging to a serial port. His design features mainly through-hole components to make the build accessible to everyone. A suitable case is yet to come, and we’re looking forward to seeing the finished product.

Can’t scrape together some of these modules on eBay? Or perhaps you prefer linear power supplies to switched- mode? No worries – here’s a super stable unregulated supply for you.

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Cheap Cat Feeder Enhances Sleep

We’ll admit it: we sometimes overcomplicate things. Look at [Peter Weissbrod’s] automated cat feeder, for example. It isn’t anything more than a bottle, a servo, some odds and ends, and an Arduino. However, it lets him sleep in without his cat waking him for service.

We looked at the code and thought, “This thing will just dispense food all the time! That’s not what you want!” Then we looked closer. [Peter] uses a common household timer to just turn the device on in the morning, let it run for a bit, and then turns it off. You can see a video of the mechanism, below.

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