The Nintendo Switch CPU Exposed

December 14, 2023 by 8 Comments

Ever wonder what’s inside a Nintendo Switch? Well, the chip is an Nvidia Tegra X1. However, if you peel back a layer, there are four ARM CPU cores inside — specifically Cortex A57 cores, which take up about two square millimeters of space on the die. The whole cluster, including some cache memory, takes up just over 13 square millimeters. [ClamChowder] takes us inside the Cortex A57 inside the Nintendo Switch in a recent post.

Interestingly, the X1 also has four A53 cores, which are more power efficient, but according to the post, Nintendo doesn’t use them. The 4 GB of DRAM is LPDDR4 memory with a theoretical bandwidth of 25.6 GB/s.

The post details the out-of-order execution and branch prediction used to improve performance. We can’t help but marvel that in our lifetime, we’ve seen computers go from giant, expensive machines to the point where a game console has 8 CPU cores and advanced things like out-of-order execution. Still, [ClamChowder] makes the point that the Switch’s processor is anemic by today’s standards, and can’t even compare with an outdated desktop CPU.

Want to program the ARM in assembly language? We can help you get started. You can even do it on a breadboard, though the LPC1114 is a pretty far cry from what even the Switch is packing under the hood.

How Germany’s Troubled Pebble Bed Reactor Came Of Age In China

December 14, 2023 by 57 Comments

Although the concept of nuclear fission is a simple and straightforward one, the many choices for fuel types, fuel design, reactor configurations, coolant types, neutron moderator or reflector types, etc. make that nuclear fission reactors have blossomed into a wide range of reactor designs, each with their own advantages and disadvantages. The story of the pebble bed reactor (PBR) is among the most interesting here, with its development winding its way from the US Manhattan Project over the Atlantic to Germany’s nuclear power industry during the 1960s, before finding a welcoming home in China’s rapidly growing nuclear power industry.

As a reactor design, PBRs do not use fuel rods like most other nuclear reactors, but rather spherical fuel elements (‘pebbles’) that are inserted at the top of the reactor vessel and extracted at the bottom, allowing for continuous refueling, while helium acts as coolant. With a strong negative temperature coefficient, the design should be extremely safe, while providing high-temperature steam that can be used for applications that otherwise require a coal boiler or gas turbine.

With China recently having put its twin-PBR HTR-PM plant into commercial operation, why is it that it was not the US, Germany or South Africa to first commercialize PBRs, but relative newcomer China?

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Polish Train Manufacturer Threatens Hackers Who Unbricked Their Trains

December 14, 2023 by 62 Comments

A week ago we covered the story of a Polish train manufacturer who was caught using software to brick their products after they had been repaired by in independent railway workshop. Now 404 Media has a follow-up story with more information, including the news that the hackers responsible for the discovery are now being threatened by the manufacturer.

The more we learn about this story the more interesting it becomes, as the Newag trains in question began failing after service as far back as 2021. In desperation after services were affected by the number of non-functional units, an employee searched online for Polish hackers and found a group called Dragon Sector. The group was able to find the issue, and are now being threatened with legal action by the manufacturer, who are citing possible safety issues.

It’s clear from where we are standing that Newag have been caught red-handed in some extremely dubious practices, and seem to have little sense of how their actions might not be the best in terms of protecting their reputation. We are guessing that the European regulators will become very interested in this case, and that meanwhile the order books of a company which puts DRM in its trains will start to look very empty indeed. You can catch our original coverage as the story broke, here.

Thanks [JohnU] for the tip.

When Is A Typewriter A Printer? When It Has A Parallel Port

December 14, 2023 by 13 Comments

If you want to talk to a typewriter using something other than your fingers on the keys, you could do a lot worse than to pick up a specimen featuring a Centronics parallel port. That’s what happened to [mlupo], who came across an old Swintec 1146 CMP and decided to hack it into an art installation.

At the push of a giant, clicky button, the typewriter now spits out family stories. This is all thanks to an Adafruit KB2040 keyboard driver being used in a new, exciting way — as a printer driver.

More specifically, the CircuitPython program running on the KB2040 takes in a text file and then sends the data one character at a time until a newline is reached. At that point, the typewriter sends a busy signal and the characters are typed.

As soon as the typewriter is no longer occupied, the data stream picks back up until the next newline or until the file is completely typed out.

Once [mlupo] figured out enough of the parallel port protocol, they were able to build a custom breakout board with the KB2040, a female parallel port, and a row of LEDs for debugging that [mlupo] kept because they look cool.

The KB2040 sets the values high on a series of the parallel port’s data pins, along with the port’s STROBE pin, which pulls low when data is ready. During each STROBE cycle, the high and low pins are read by the Swintec as a binary character.

Of course, you can always use the power of Pi to build your own modern typewriter.

Thanks to [foamyguy] for the tip!

Porting CP/M To A Z80 Thing

December 13, 2023 by 13 Comments

It is hard to describe the Brother SuperPowerNote. It looks like a big old Z80-based laptop, but it says it is a notebook. The label on it says (with lots of exclamation marks) that it is a word processor, a communications system, a personal scheduler, and a spreadsheet organizer. Brother also promises on the label that it will “Increase your power to perform on the job, on the road or at home!” Plenty of exclamation marks to go around. The label also touts DOS or Windows, but [Poking Technology] didn’t want that. He wanted CP/M. See how he did it in the video below.

This is a very early laptop-style word processor with a floppy and a strange-looking screen. It also had serial and parallel ports, odd for a word processor, and probably justified the “communication system” claim on the label.

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The Geometry Of Transistors

December 13, 2023 by 10 Comments

Building things in a lab is easy, at least when compared to scaling up for mass production. That’s why there are so many articles about fusion being right around the corner, or battery technology that’ll allow aviation to switch away from fossil fuels, or any number of other miraculous solutions that never come into being. They simply don’t scale or can’t be manufactured in a cost effective way. But even when they are miraculous and can be produced on a massive scale, as is the case for things like transistors, there are some oddities that come up as a result of the process of making so many. This video goes into some of the intricacies of a bipolar junction transistor (BJT) and why it looks the way it does.

The BJT in this video is a fairly standard NPN type, with three layers of silicon acting as emitter, base, and collector. Typically when learning about electronics devices the drawings of them are simplified two-dimensional block diagrams, but under a microscope this transistor at first appears nothing like the models shown in the textbook. Instead it resembles more of a bird’s foot with a few small wires attached. The bird’s foot shape is a result of attempting to lower the undesirable resistances of the device and improve its performance, and some of its other quirks are due to the manufacturing process. That process starts with a much larger layer of doped silicon that will eventually become the collector, and then the other two, much smaller, layers of the transistor deposited on top of the collector. This also explains while it looks like there are only two layers upon first glance, and also shows that the horizontal diagram used to model the device is actually positioned vertically in the real world.

For most of the processes in our daily lives, the transistor has largely been abstracted away. We don’t have to think about them in a computer that much anymore, and unless work is being done on high-wattage power electronics devices, radios, or audio amplifiers it’s not likely that an average person will run into a transistor. But this video goes a long way to explaining the basics of one of the fundamental building blocks of the modern world for those willing to take a dive into the physics. Take a look at this video as well for an intuitive explanation of the close cousin of the BJT, the field-effect transistor.

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Bluetooth As Proxy For Occupancy

December 13, 2023 by 59 Comments

During [Matt]’s first year of college, he found in a roundabout way that he could avoid crowds in the dining hall by accessing publicly available occupancy data that the dining hall collected. Presumably this was data for the dining hall to use internally, but with the right API calls anyone could use the information to figure out the best times to eat. But when the dining hall switched providers, this information feed disappeared. Instead of resigning himself to live in a world without real-time data on the state of the dining hall, he recreated the way the original provider counted occupancy: by using Bluetooth as a proxy for occupancy.

Bluetooth devices like smartphones, fitness sensors, and other peripherals often send out advertising packets into the aether, to alert other devices to their presence and help initiate connections between devices. By sniffing these advertising packets, it’s possible to get a rough estimate of the number of people in one particular place, assuming most people in the area will be carrying a smartphone or something of that nature. [Matt]’s Bluetooth-sniffing device is based on the ESP32 set up to simply count the number of unique devices it finds. He had some trouble with large crowds, though, as the first ESP32 device he chose didn’t have enough RAM to store more than a few hundred IDs and would crash once the memory filled. Switching to a more robust module seems to have solved that issue, and with a few rounds of testing he has a workable prototype that can run for long periods and log at least as many Bluetooth devices passing by as there are within its range.

While [Matt] hasn’t deployed this to the dining hall yet, with this framework in place most of the work has been done that, at least in theory, one of these modules could be easily placed anywhere someone was interested in collecting occupancy data. He has plans to submit his project to the university, to research the topic further, and potentially sell these to businesses interested in that kind of data. This isn’t an idea limited to the ESP32, either. We’ve seen similar projects built using the Raspberry Pi’s wireless capabilities that perform similar tasks as this one.

Thanks to [Adrian] for the tip!