$50 10Gbps Mesh Network Uses USB4

You want to build a cluster of computers, but you need a high-speed network fabric that can connect anything to anything. Big bucks, right? [Fang-Pen] developed a 10 Gbps full-mesh network using USB4 that cost him under $50. The first part of the post is about selecting a low-power mini PC, but if you skip down to the “Networking” section, you’ll find the details on the cluster.

The machines selected have two USB4 ports. In theory, you can transfer 40 Gbps on these ports. In reality, the cluster only hit 11 Gbps, but that’s still well above common Ethernet speeds. [Fang-Pen] has yet to determine why he isn’t getting even faster speeds.

Since Linux is Linux, there is a module for networking over Thunderbolt, so the rest is basically set up. There are, of course, some limitations. First, it is only fully connected because the cluster has three computers. More computers would need more USB4 ports or more hardware.

In addition, the standard says you can only count on full speed with cables 0.8 meters or shorter. However, that’s the 40 Gbps number. We wondered if a 2 m cable, rated at 20 Gbps, would have still managed 11 Gbps in this setup. A 10GBASE-T network, on the other hand, should allow 100-meter cables. But for a cluster of computers, do you really care?

We’d be interested to see this idea extended to more nodes. High-speed fabric can be useful in networked disk servers, parallel computing, and probably some other scenarios. We’ve seen 10G Ethernet on the Pi, although the PCI bus limited it to about 3.6 Gbps. For reference, we saw another three computer networks with 10GBASE-T done for about $130 with similar limitations.

Reverse-Engineering The ESP32’s WiFi Binary Blob With A Faraday Cage

The Faraday cage constructed by Jasper Devreker.
The Faraday cage constructed by Jasper Devreker.

As part of a team reverse-engineering the binary blob driver for the ESP32’s WiFi feature at Ghent University, [Jasper Devreker] saw himself faced with the need to better isolate the network packets coming from the ESP32-under-test. This is a tough call in today’s WiFi and 2.4 GHz flooded airwaves. To eliminate all this noise, [Jasper] had to build a Faraday cage, but ideally without racking up a massive invoice and/or relying on second-hand parts scavenged from eBay.

We previously reported on this reverse-engineering project, which has since seen an update. Although progress has been made, filtering out just the packets they were interested in was a big challenge. The solution was a Faraday cage, but on a tight budget.

Rather than relying on exotic power filters, [Jasper] put a battery inside a Faraday cage he constructed out of wood and conductive fabric. To get Ethernet data in and out, a fiber link was used inside a copper tube. Initial testing was done using a Raspberry Pi running usbip and a WiFi dongle.  The Faraday cage provided enough attenuation that the dongle couldn’t pick up any external WiFi signals in listening mode.

The total cost of this build came down to a hair over €291, which makes it feasible for a lot of RF experiments by hobbyists and others. We wish [Jasper] and the rest of the team a lot of luck in figuring out the remaining secrets of Espressif’s binary WiFi blob using this new tool.

802.11ah Wi-Fi HaLOW: The 1 Kilometer WiFi Standard

You too can add long-distance WiFi to your laptop with this new not-quite dongle solution. (Credit: Ben Jeffery)
You, too, can add long-distance WiFi to your laptop with this new not-quite dongle solution. (Credit: Ben Jeffery)

The 802.11ah WiFi (HaLow) standard is fairly new, having only been introduced in 2017. It’s supposed to fall somewhere between standard WiFi used in domiciles and offices and the longer range but low-bitrate LoRaWAN, ZigBee, and others, with bandwidth measured in megabits per second. In a recent video, [Ben Jeffery] looks at the 802.11ah chipsets available today and some products integrating these.

The primary vendors selling these chipsets are TaiXin Semiconductor (TXW8301), Morse Micro (MM6108), and Newracom (NRC7394), with a range of manufacturers selling modules integrating these. Among the products using these, [Ben] found an Ethernet range extender kit (pictured) that takes 12V input as power, along with Ethernet. Running some distance tests in a quarry showed that 300 meters was no problem getting a strong signal, though adding some trees between the two transceivers did attenuate the signal somewhat.

Another interesting product [Ben] tested is what is essentially an 802.11ah-based WiFi extender, using an 802.11ah link between the server node – with an Ethernet socket – and a client that features a standard 2.4 GHz 802.11n that most WiFi-enabled devices can connect to. Using this, he was able to provide a solid ~10 Mbps link to a cabin near the main house (~10 meters) through two outside walls. What makes 802.11ah so interesting is that it is directly compatible with standard Ethernet and WiFi protocols and uses the 900 MHz spectrum, for which a wide range of alternative antennae exist that can conceivably extend the range even more.

(Thanks to [Keith Olson] for the tip)

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CH32 RISC-V MCUs Get Official Arduino Support

Like many of you, we’ve been keeping a close eye on the CH32 family of RISC-V microcontrollers from WCH Electronics. You can get the CH32V003, featuring 2 kB RAM and 16 kB of flash for under fifteen cents, and the higher-end models include impressive features like onboard Ethernet. But while the hardware is definitely interesting, the software side of things has been a little rocky compared to what we’ve come to expect from modern MCUs.

Things should start looking up a bit though with the release of an Arduino core for the CH32 direct from WCH themselves. It’s been tested on Windows, Linux, and Mac, and supports the CH32V00x, CH32V10x, CH32V20x, CH32V30x, and CH32X035 chips. Getting it installed is as easy as adding the URL to the Arduino IDE’s Boards Manager interface, though as the video below shows, running it on Linux does require an extra step or two.

So far, we’ve seen several projects, like this temperature sensor or this holiday gizmo that use [cnlohr]’s open-source toolchain. But there’s no question that plenty of hobbyists out there feel more comfortable in the Arduino environment, and if those folks are now able to pick up a CH32 and do something cool, that means more people jumping on board, more libraries developed, more demo code written…you get the idea.

Just like the ESP8266’s popularity exploded when it was added to the Arduino IDE, we’ve got high hopes for the CH32 family in the coming months.

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Parachute Drops Are Still A Viable Solution For Data Recovery From High Altitude Missions

Once upon a time, when the earliest spy satellites were developed, there wasn’t an easy way to send high-quality image data over the air. The satellites would capture images on film and dump out cartridges back to earth with parachutes that would be recovered by military planes.

It all sounds so archaic, so Rube Goldberg, so 1957. And yet, it’s still a viable method for recovering big globs of data from high altitude missions today. Really, you ask? Oh, yes indeed—why, NASA’s gotten back into the habit just recently!

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Raspberry Pi 5 Goes Under The X-ray

Most Hackaday readers will know to some extent what lies inside their computer, even if this is only at a block diagram level listing the peripherals. But what is physically on a modern computer board? [Jeff Geerling] has subjected a Raspberry Pi 5 to a medical imager, and shares with us the many layers of parts and PCB he found there. With a six-layer board and a heap of large BGA chips on it, there’s a lot to look at.

For readers who are used to working with printed circuit boards, it’s likely the techniques involved in the design will not be new. For us, the magic lies in the scale. The sheer number of interconnects on the board is impressive enough, but when it becomes possible to peer into the SoC package it becomes evident that there’s an internal PCB with some of the smallest vias we have ever seen. [Jeff] goes on to show us part by part around the board, on the way reminding us that some of the earliest Pi boards had to be reworked to replace Ethernet jacks without magnetics.

There’s a beauty to these ghostly images which might not be apparent to anyone who hasn’t stared obsessively at a PCB in a CAD package while it takes shape. The images show the work of the PCB designer’s art at a fine scale. We’d almost go as far as to suggest they be viewed as fine art instead of industrial design. Take a look, the video is below the break.

If this art is a bit big for you, then look at ASIC design – which takes things down to the microscopic level of the doped silicon structures within these amazing chips.

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Affordable Networking For Your Classic Mac

The Mac SE and in particular the Mac SE/30 number among the more sought-after of the classic all-in-one Apple computers, and consequently their peripherals including network cards are also hard to find and pricey. Even attempts at re-creating them can be expensive, usually because the chips used back in the day are now nearly unobtainable. But if the search is widened to other silicon it becomes possible to create substitutes, as [Richard Halkyard] is doing with a modern version of the SE Ethernet card.

The chip which makes this possible is the Microchip ENC624J600, an embedded 10/100 Ethernet controller with an impressively configurable interface that can be easily mated to the 68k bus. For The SE it’s mapped to a memory area, while for the /30 there can be a declaration ROM which informs the machine where it is.

This is an as yet unfinished project, a work in progress. But it deserves to succeed, and if we can provide encouragement by featuring it here then it’s definitely worth a look. Or course, this is by no means the only replacement for an original board.

SE/30 picture: Cornellanense, CC BY-SA 4.0.