A small circuit board glowing purple inset with computer code

Power Cycling Museum Computers On The Cheap

March 18, 2022 by Chris Wilkinson 32 Comments

Flicking a circuit breaker to power cycle hundreds of desktop computers inside interactive museum exhibits is hardly ideal. Computers tend to get cranky when improperly shutdown, and there’s an non-zero risk of data loss. However, financial concerns ruled out commercial computer management solutions, and manually shutting down each exhibit at the end of the day is not practical. Tasked with finding a solution, [Jeff Glass] mixed off-the-shelf UPS (uninterruptible power supply) hardware, a Featherwing and some Python to give the museum’s computer-run exhibits a fighting chance.

Without drastically changing the one-touch end-of-day procedure, the only way to properly shutdown the hundreds of computers embedded in the museum exhibits involved using several UPS units, keeping the PCs briefly powered on after the mains power was cut. This in itself solves nothing – while the UPS can trigger a safe shutdown via USB, this signal could only be received by a single PC. These are off-the-shelf consumer grade units, and were never intended to safely shut down more than one computer at a time. However, each 300 watt UPS unit is very capable of powering multiple computers, the only limitation is the shutdown signal and the single USB connection.

To get around this, the Windows task scheduling service was setup to be triggered by the UPS shutdown signal, which itself then triggered a custom Python script. This script then relays the shutdown signal from the UPS to every other computer in the museum, before shutting itself down for the evening.

While many computers can be enabled to boot on power loss, the UPS and safe shutdown scripts meant that this wasn’t an option. To get around this, an ESP32 Featherwing and a little bit if CircuitPython code sends out WOL (wake-on-LAN) signals over Ethernet automatically on power up. This unit is powered by a non-UPS backed power outlet, meaning that it only sends the WOL signal in the morning when mains power is restored via the circuit breaker.

There are undoubtedly a variety of alternative solutions that appear ‘better’ on paper, but these may gloss over the potential costs and disruption to a multi-acre museum. Working within the constraints of reality means that the less obvious fix often ends up being the right one. How would you have tackled this problem? Sound off in the comments below. And while you’re here, make sure to check out our coverage of other UPS solutions, like this supercap UPS.

An Old Typewriter Speaks To The World

March 17, 2022 by Jenny List 20 Comments

Typewriters are something which was once ubiquitous, yet which abruptly faded away and are now a rare sight. There was a period of a few years in which electric typewriters and computers existed side-by-side though, and it’s one of these which [Jonah Brüchert] has experimented with connecting to a computer for use as a printer or terminal.

The machine in question is a SIGMA SM 8200i typewriter, which is a rebadged version of the East German Erika S3004. It has an intriguing 26-pin connector on its side which provides access to a 1200 baud serial port. It uses its own character encoding dubbed “gdrascii”, for which there is a Python library that he could port to Rust. The result is a terminal in the old style, from the days when access to a computer was through a teletype rather than a screen. All that’s missing is a punched tape reader at its side!

We’ve featured a lot of typewriters here over the ears, but this isn’t the first that has received a terminal conversion.

Mini PC with the mod described, a large tower fan sticking out of a hole in the top cover

MiniPC Surgery Makes It 50% Cooler

March 13, 2022 by Arya Voronova 27 Comments

[G3R] writes to us about a mod they did on a HP ProDesk/EliteDesk 400 G3 miniPC they use as a home emulation center. The miniPC would overheat as soon as the CPU load increased, resulting in frame drops and stutters, as well as throttling CPU. [G3R] took the original cooling solution, threw out half of it and modified the remaining half to accept a tower CPU cooler.

The modification is invasive in all the right ways. [G3R] shows how to de-fin the current heatsink and smooth it over with a… welder? Our guess is that the heatsink fins were soldered to the heatsink base, and in that case, a heat gun should also work. Afterwards, you’re supposed to cut a hole in the upper case, then re-wire the fan connections, and create custom brackets to attach the tower fan – [G3R] explains how to do it all and what to watch out for.

The results are fascinating. After performing the mod, both idle and under-load temps got cut down by 50%! Idle temps went from 50 to 25 °C, and under-load temps dropped from 79 to 40 °C – surely, with way less throttling involved. Not only this lets [G3R] play Breath Of The Wild without hiccups, it also certainly improves overall lifespan of the mini-PC, despite the intervention being mechanically harsh.

Making our devices, quite literally, cooler is a venerable tradition of hackers. Just a few weeks ago, we covered a simple 3D printable LGA 1700 CPU bracket which can gain you some much-desired thermal contact. Sometimes we encounter proprietary and weird cooling fans that fail, and then we understand their workings and build a substitute. And, even if your GPU was never meant to have a fan, you can add one anyway!

Modular Pockit Computer Is More Than Meets The Eye

March 12, 2022 by Ryan Flowers 38 Comments

“Modular” and “Computer” have historically been on the opposite ends of a rather awkward spectrum. One could argue that a hobbyist grade PC is modular, but only to a point. Re-configuring it on the fly is not readily possible. Modular laptops are slowly happening, but what about handheld devices, where our needs might change on a regular basis?

Enter the Pockit: a fully modular IoT/edge computing device that can be reconfigured on the fly without having to reprogram it. Don’t browse away from this page without watching the demonstration video below the break. It just might be the “mother of all demos” for the current decade.

A modular base provides basic computing power in the form of a Raspberry Pi, like many other projects. The base has twelve magnetic connectors, each with twenty I/O and power pins. When a module is added, the operating system detects the new module and loads an appropriate program on the fly. When more modules are loaded, it automatically configures itself so that all modules have a purpose. This allows the Pockit to be an integrated IoT device, an edge computing powerhouse, a desktop computer, a Blackberry-esque handheld, or a touch screen tablet, and so many more things.

For example, if a camera is added, it displays an image on a screen — if there’s a screen. If a button is added, it automatically takes a picture when the button is pressed. If you want the camera to be motion activated, just add a motion sensor. Done. External devices can be controlled with relays and home automation integrates almost seamlessly.

There are a great number of features that we’re glossing over for the sake of getting to the point: Go watch the video and when you’re done, perhaps you’ll be as astonished as we are. We’ve expressed our love of modular hardware like the Pockit in the past, and after watching this demo, we can only hope that this is what the future of computing and electronics looks like!

Continue reading “Modular Pockit Computer Is More Than Meets The Eye” →

Top side of the VL670 breakout board, with two USB connectors and the VL670 chip in the center.

A Chip To Bridge The USB 2 – USB 3 Divide

March 7, 2022 by Arya Voronova 35 Comments

On Twitter, [whitequark] has found and highlighted an intriguing design – a breakout board for the VL670, accompanied by an extensive yet very easy to digest write-up about its usefulness and inner workings. The VL670 is a chip that addresses a surprising problem – converting USB 2.0 signals into USB 3.0.

If you have a USB 2.0 device and a host with only USB 3.0 signals available, this chip is for you. It might be puzzling – why is this even needed? It’s about the little-known dark secret of USB3, that anyone can deduce if they ever have to deal with a 9-pin USB 3.0 connector where one of the three differential pairs doesn’t quite make contact.

When you see a blue “3.0” port, it’s actually USB 2 and USB 3 — two separate interfaces joined into a single connector. USB 3 uses two single-directional differential pairs, akin to PCI-E, whereas USB 2 uses a single bidirectional one, and the two interfaces on a blue connector operate basically independently of each other. There’s many implications to this that are counterintuitive if you simply take “USB 3.0” for “faster backwards-compatible USB”, and they have painful consequences.

For instance, USB 3 hub ICs have two separate hub entities inside – one for USB 3 and one for USB 2. Even if you have a USB 3 hub plugged into a USB 3 port, multiple USB 2 devices plugged into it still cannot break through the USB 2 uplink limit of 480 MBps. If you ever thought that a faster hub with a faster uplink would fix your USB 2 device speed problems – USB-IF engineers, apparently, thought differently; and you might have to find a workaround for your “many cheap SDRs and Pi 4 in a box” setup. Continue reading “A Chip To Bridge The USB 2 – USB 3 Divide” →

Are Apple Trying To Patent The Home Computer 45 Years Too Late?

March 4, 2022 by Jenny List 64 Comments

In our recent piece marking the 10th anniversary of the Raspberry Pi, we praised their all-in-one Raspberry Pi 400 computer for having so far succeeded in attracting no competing products. It seems that assessment might be premature, because it emerges that Apple have filed a patent application for “A computer in an input device” that looks very much like the Pi 400. In fact we’d go further than that, it looks very much like any of a number of classic home computers from back in the day, to the extent that we’re left wondering what exactly Apple think is novel enough to patent.

A Raspberry Pi 400 all-in-one keyboard console computer — Looks pretty similar to us.

Reading the patent it appears to be a transparent catch-all for all-in-one computers, with the possible exception of “A singular input/output port“, meaning that the only port on the device would be a single USB-C port that could take power, communicate with peripherals, and drive the display. Either way, this seems an extremely weak claim of novelty, if only because we think that a few of the more recent Android phones with keyboards might constitute prior art.

We’re sure that Apple’s lawyers will have their arguments at the ready, but we can’t help wondering whether they’ve fallen for the old joke about Apple fanboys claiming the company invented something when in fact they’ve finally adopted it years after the competition.

Thinking back to the glory days of 8-bit computers for a moment, we’re curious which was the first to sport a form factor little larger than its keyboard. Apple’s own Apple ][ wouldn’t count because the bulk of the machine is behind the keyboard, but for example machines such as Commodore’s VIC-20 or Sinclair’s ZX Spectrum could be said to be all-in-one keyboard computers. Can anyone provide an all-in-one model that predates those two?

You can read our Raspberry Pi 400 review if the all-in-one interests you.

Via Extreme Tech.

A purple 3D-printed case with an LCD screen on the front and Pikachu on top

Avoid Repetitive Strain Injury With Machine Learning – And Pikachu

March 4, 2022 by Robin Kearey 1 Comment

The humble mouse has been an essential part of the desktop computing experience ever since the original Apple Macintosh popularized it in 1984. While mice enabled user-friendly GUIs, thus making computers accessible to more people than ever, they also caused a significant increase in repetitive strain injuries (RSI). Mainly caused by poor posture and stress, RSI can lead to pain, numbness and tingling sensations in the hand and arm, which the user might only notice when it’s too late.

Hoping to catch signs of RSI before it manifests itself, [kutluhan_aktar] built a device that allows him to track mouse fatigue. It does so through two sensors: one that measures galvanic skin response (GSR) and another that performs electromyography (EMG). Together, these two measurements should give an indication of the amount of muscle soreness. The sensor readout circuits are connected to a Wio Terminal, a small ARM Cortex-M4 development board with a 2.4″ LCD.

However, calculating muscle soreness is not as simple as just adding a few numbers together; in fact the link between the sensor data and the muscles’ state of health is complicated enough that [kutluhan] decided to train a TensorFlow artificial neural network (ANN), taking into account observed stress levels collected in real life. The network ran on the Wio while he used the mouse, pressing buttons to indicate the amount of stress he experienced. After a few rounds of training he ended up with a network that reached an accuracy of more than 80%.

[kutluhan] also designed a rather neat 3D printed enclosure to house the sensor readout boards as well as a battery to power the Wio Terminal. Naturally, the case was graced by a 3D rendition of Pikachu on top (get it? a mouse Pokémon that can paralyze its opponents!). We’ve seen [kutluhan]’s fondness for Pokémon-themed projects in his earlier Jigglypuff CO2 sensor.

Although the setup with multiple sensors doesn’t seem too practical for everyday use, the Mouse Fatigue Estimator might be a useful tool to train yourself to keep good posture and avoid stress while using a mouse. If you also use a keyboard (and who doesn’t?), make sure you’re using that correctly as well.

Continue reading “Avoid Repetitive Strain Injury With Machine Learning – And Pikachu” →