Often, reprogramming a microcontroller involves placing it in reset, flashing the code, and letting it fire back up. It usually involves shutting the chip down entirely. However, [bor0] has built a virtual machine that runs on the ESP32, allowing for dynamic program updates to happen.
The code is inspired by the CHIP-8, a relatively ancient interpreter that had some gaming applications. [bor0] had already created a VM simulating the CHIP-8, and repurposed it here, taking out the gaming-related drawing instructions and replacing them with those that control IO pins. Registers have also been changed to 16 bits for added flexibility and headroom.
It’s probably not something with immediate ground-breaking applications for most people, but it’s a different way of working with and programming the ESP32, and that’s pretty neat.
In a sign that the United States government’s export restrictions on semiconductor sales to Russia due to its war against Ukraine have been enacted swiftly, multiplereports have emerged today that both Intel and AMD have suspended chip sales to Russia. In addition, reports have also emerged that TSMC’s decision to participate in the sanctions will thwart Russia’s supply of homegrown chips. We have reached out to Intel, AMD, and Nvidia for comment.
The Russian media outlets also claim that the suspensions have been confirmed by the Association of Russian Developers and Electronics Manufacturers (ARPE). Additionally, Chinese IT companies are said to have been notified by Intel that sales to Russia have been banned.
The extent of the halted sales is currently unclear. The new export restrictions are primarily aimed at chips for military purposes or dual-use chips that could be used for both civilian and military purposes. That means sales of most consumer-focused chips, like AMD’s Ryzen and Intel’s Core chips, likely won’t be impacted. However, it is widely expected that there will be a temporary halt for all semiconductor sales to Russia as companies work to decide which products are impacted. Additionally, the US DoC has added 49 Russian companies to the Entity List, and those companies aren’t eligible to purchase any type of chip.
The late 90s and early 2000s were a breakout time for mobile phones, with cheap GSM handsets ushering in the era in which pretty much everybody had a phone. Back then, a popular way to customize one’s phone was to install a sticker that would flash when the phone rang. These required no batteries or any other connection to the phone, and [Big Clive] has dived in to explain how they worked.
It’s an old-fashioned teardown that requires a bit of cutting to get inside the sticker itself. A typical example had three LEDs in series for a total voltage drop of around 7V, hooked up to two diodes and a PCB trace antenna. A later evolution used raw unpackaged components bonded to the PCB. Future versions went down to a single diode, using the LEDs to serve as the second. The basic theory was that the PCB traces would pick up RF transmitted by the phone when a call was coming in, lighting the LEDs.
In the 2G era, the freuqencies used were on the order of 300 MHz to 1.9GHz. A combination of the change in frequencies used by modern phone technology and the lower transmit powers used by handsets means that the stickers don’t work properly with modern phones according to [Big Clive].
The joint development team of Professor Shibata (the University of Tokyo), JEOL Ltd. and Monash University succeeded in directly observing an atomic magnetic field, the origin of magnets (magnetic force), for the first time in the world. The observation was conducted using the newly developed Magnetic-field-free Atomic-Resolution STEM (MARS). This team had already succeeded in observing the electric field inside atoms for the first time in 2012. However, since the magnetic fields in atoms are extremely weak compared with electric fields, the technology to observe the magnetic fields had been unexplored since the development of electron microscopes. This is an epoch-making achievement that will rewrite the history of microscope development.
Electron microscopes have the highest spatial resolution among all currently used microscopes. However, in order to achieve ultra-high resolution so that atoms can be observed directly, we have to observe the sample by placing it in an extremely strong lens magnetic field. Therefore, atomic observation of magnetic materials that are strongly affected by the lens magnetic field such as magnets and steels had been impossible for many years. For this difficult problem, the team succeeded in developing a lens that has a completely new structure in 2019. Using this new lens, the team realized atomic observation of magnetic materials, which is not affected by the lens magnetic field. The team’s next goal was to observe the magnetic fields of atoms, which are the origin of magnets (magnetic force), and they continued technological development to achieve the goal.
This time, the joint development team took on the challenge of observing the magnetic fields of iron (Fe) atoms in a hematite crystal (α-Fe2O3) by loading MARS with a newly developed high-sensitivity high-speed detector, and further using computer image processing technology. To observe the magnetic fields, they used the Differential Phase Contrast (DPC) method at atomic resolution, which is an ultrahigh-resolution local electromagnetic field measurement method using a scanning transmission electron microscope (STEM), developed by Professor Shibata et al. The results directly demonstrated that iron atoms themselves are small magnets (atomic magnet). The results also clarified the origin of magnetism (antiferromagnetism) exhibited by hematite at the atomic level.
Nature is a never-ending source of inspiration for scientists, but our artificial devices usually don’t communicate well with the real thing. Now, researchers at Linköping University have created artificial organic neurons and synapses that can integrate with natural biological systems, and demonstrated this by making a Venus flytrap close on demand.
The new artificial neurons build on the team’s earlier versions, which were organic electrochemical circuits printed onto thin plastic film. Since they’re made out of polymers that can conduct either positive or negative ions, these circuits form the basis of transistors. In the new study, the team optimized these transistors and used them to build artificial neurons and synapses, and connect them to biological systems.
When the transistors detect concentrations of ions with certain charges, they switch, producing a signal that can then be picked up by other neurons. Importantly, biological neurons operate on these same ion signals, meaning artificial and natural nerve cells can be connected.
Using a new fabrication technique, NIMS has developed a diamond field-effect transistor (FET) with high hole mobility, which allows reduced conduction loss and higher operational speed. This new FET also exhibits normally off behavior (i.e., electric current flow through the transistor ceases when no gate voltage is applied, a feature that makes electronic devices safer). These results may facilitate the development of low-loss power conversion and high-speed communications devices.
Diamond has excellent wide bandgap semiconductor properties: its bandgap is larger than those of silicon carbide and gallium nitride, which are already in practical use. Diamond therefore could potentially be used to create power electronics and communications devices capable of operating more energy efficiently at higher speeds, voltages and temperatures. A number of R&D projects have previously been carried out with the aim of creating FETs using hydrogen-terminated diamonds (i.e., diamonds with their superficial carbon atoms covalently bonded with hydrogen atoms). However, these efforts have failed to fully exploit diamonds’ excellent wide bandgap semiconductor properties: the hole mobility (a measure of how quickly holes can move) of these diamond-integrated transistors was only 1–10% that of the diamonds before integration.
The NIMS research team succeeded in developing a high-performance FET by using hexagonal boron nitride (h-BN) as a gate insulator instead of conventionally used oxides (e.g., alumina), and by employing a new fabrication technique capable of preventing the surface of hydrogen-terminated diamond from being exposed to air. At high hole densities, the hole mobility of this FET was five times that of conventional FETs with oxide gate insulators. FETs with high hole mobility can operate with lower electrical resistance, thereby reducing conduction loss, and can be used to develop higher speed and smaller electronic devices. The team also demonstrated normally-off operation of the FET, an important feature for power electronics applications. The new fabrication technique enabled removal of electron acceptors from the surface of the hydrogen-terminated diamond.
Humans have been trying to understand how the brain works and how it acquires information for centuries. While neuroscientists now have a pretty good understanding of how different parts of the brain work and what their function is, many questions remain unanswered; thus, a unified neuroscience theory is still lacking.
In recent years, computer scientists have been trying to create computational tools that artificially recreate the functions and processes of the human brain. New neuroscience theories clarifying how the brain makes predictions could help to significantly enhance these tools so that they replicate neural functions in increasingly realistic ways.
Researchers at the Canadian Centre for Behavioural Neuroscience in Lethbridge, Canada have recently carried out a study investigating how individual neurons learn and make predictions about the future. Their findings, published in Nature Machine Intelligence, suggest that the ability of single neurons to predict their future activity could offer a new learning mechanism.
Whether you live in an apartment downtown or in a detached house in the suburbs, if your mailbox is not built into your home you’ll have to go outside to see if anything’s there. But how do you prevent that dreadful feeling of disappointment when you find your mailbox empty? Well, we’re living in 2022, so today your mailbox is just another Thing to connect to the Internet of Things. And that’s exactly what [fhuable] did when he made a solar powered IoT mailbox.
The basic idea was to equip a mailbox with a camera and have it send over pictures of its contents. An ESP32-Cam module could do just that: with a 1,600 × 1,200 camera sensor, a 160 MHz CPU and an integrated WiFi adapter, [fhuable] just needed to write an Arduino sketch to have it take a picture every few hours and upload it to an FTP server.
But since running a long cable all the way from the house was not an attractive option, the whole module had to be completely wireless. [fhuable] decided to power it using a single 18,650 lithium ion cell, which gets topped up continuously thanks to a 1.5 W solar panel mounted on the roof of the mailbox. The other parts are housed in a 3D-printed enclosure that’s completely sealed to keep out moisture.
More recently, digital twins have been the focus of a European Union-funded project that seeks to clone a patient’s entire brain. Dubbed Neurotwin, the research project aims to create virtual models that can be used to predict the effects of stimulation for the treatment of neurological disorders—including epilepsy and Alzheimer’s disease. When it comes to epilepsy, non-invasive stimulations (where electrical currents are painlessly delivered to the brain) have proven effective in tackling seizures. Given how drugs don’t help a third of epilepsy patients, the technology is coveted yet needs refinement. This is where virtual clones come in.
“The digital avatar is essentially a mathematical model running on a computer,” Giulio Ruffini, coordinator of the Neurotwin project, told WIRED. Including a network of embedded “neural mass models,” the technology hopes to create a map of the neural connections in the brain—a concept termed as the ‘connectome’. “In the case of epilepsy, some areas of the connectome could become overexcited,” the outlet mentioned. “In the case of, say, stroke, the connectome might be altered.” Once the digital clone has been created by the team, with about half an hour-worth of magnetic resonance imaging (MRI) data and ten minutes of electroencephalography (EEG) readings to capture electrical activities and realistically simulate the brain’s main tissues (including the scalp, skull, cerebrospinal fluid, and grey and white matter), it can then be used to optimise stimulation of the real patient’s brain.
According to Ruffini, this is possible “because we can run endless simulations on the computer until we find what we need. It is, in this sense, like a weather forecasting computational model.”
