A common sight on factory floors, stack lights are used to indicate the status of machinery to anyone within visual range. But hackers have found out you can pick them up fairly cheap online, so we’ve started to see them used as indicators in slightly more mundane situations than they were originally intended for. [Tyler Ward] recently decided he wanted his build own network controlled stack light, and thought it would double as a great opportunity to dive into the world of Power Over Ethernet (PoE).
Now the easy way to do this would be to take the Raspberry Pi, attach the official PoE Hat to it, and toss it into a nice enclosure. Write some code that toggles the GPIO pins attached to the LEDs in the stack light, and call it a day. Would be done in an afternoon and you could be showing it off on Reddit by dinner time. But that’s not exactly what [Tyler] had in mind.
On the software side [Tyler] has developed a firmware for the ESP32 that supports both Art-Net and RDM protocols, which are subsets of the larger DMX protocol. That means the controller should be compatible with existing software designed for controlling theatrical lighting systems. If you’d rather take a more direct approach, the firmware also sports a web interface and simple HTTP API to provide some additional flexibility.
Using a pair of Dell laptops connected back to back with an Ethernet cable, the same speed-switching trick was employed. However, most hardware takes longer to switch speeds than the Pi 4; usually on the order of 2-5 seconds. This limited the signalling speed, but [Jacek] was able to set this up to exfiltrate data using QRSS, also known as very slow speed Morse code. The best result was picking up a signal from 10 meters away, although [Jacek] suspects this could be improved with better antenna hardware.
The Gigablox takes its mission seriously, with its compact size the ultimate design goal. The entire switch fits on a tiny 45 mm x 45 mm PCB. To this end, it eschews the common RJ45 connector, which is bulkier than necessary. Instead, thin Molex PicoBlade connectors are used for the five ports on board. Cables are included to convert between the two connectors, and obviously crimping ones own is easy to do, too. For those who need to connect more devices, several Gigablox can be hooked up in the same way as any other Ethernet switch. The Gigablox is a non-blocking switch, too – meaning all five ports can run at full speed simultaneously.
The design is the sequel to the SwitchBlox, and the later SwitchBlox Nano, both designed by [Josh Elijah] earlier this year. The pace of development is impressive, and it’s great to see [Josh] bring Gigabit speeds to the compact form factor. We can imagine a few good uses for these boards; share your best ideas in the comments below! Video after the break.
September 30th, 1980 is the day when Ethernet was first commercially introduced, making it exactly forty years ago this year. It was first defined in a patent filed by Xerox as a 10 Mb/s networking protocol in 1975, introduced to the market in 1980 and subsequently standardized in 1983 by the IEEE as IEEE 802.3. Over the next thirty-seven years, this standard would see numerous updates and revisions.
Included in the present Ethernet standard are not just the different speed grades from the original 10 Mbit/s to today’s maximum 400 Gb/s speeds, but also the countless changes to the core protocol to enable these ever higher data rates, not to mention new applications of Ethernet such as power delivery and backplane routing. The reliability and cost-effectiveness of Ethernet would result in the 1990 10BASE-T Ethernet standard (802.3i-1990) that gradually found itself implemented on desktop PCs.
As far as consumer network hardware goes, we’re all expected to be pretty happy with 802.11n WiFi and Gigabit Ethernet over Cat 6 cables. For most home users, that’s plenty of bandwidth for streaming movies and posting K-pop fancams to Twitter on a daily basis. If you want a fatter pipe, things can get expensive, fast. However, [TobleMiner] found a way to use surplus server-grade cards in a regular PC – providing huge bandwidth on a budget.
HPE’s FlexibleLOM standard consists of a special edge connector on HPE servers that lets the end-user fit a variety of network adapters in a form factor designed specifically for blade and rack mount servers. At the electrical level, it’s simply PCI-Express 8x. FlexibleLOM network cards are built for high-speed data center use, often featuring SFP+ and QSFP+ interfaces capable of 10 gigabit and 40 gigabit speeds, respectively.
These cards can be had for under $20 on eBay, but won’t fit in a standard PCI-Express slot. Enter [ToberMiner]’s adapter, which hooks up the relevant PCI-Express lines to where they need to go, and mechanically adapts the FlexibleLOM hardware to fit in a regular ATX PC case.
[PMercier] clearly loves his old Tektronix TDS3014 scope, which did however lack essentially modern connectivity such as an Ethernet port for control and a USB port for a convenient way to capture screenshots. So he decided to do some in-depth reverse engineering and design his own expansion card for it. The scope already has an expansion port and an expansion card, but given this model was first released in 1998, purchasing an OEM part was not going to be an option.
They don’t make ’em like they used to. Test equipment is today is built to last a decade — but usually lives on much longer. This is certainly true for the previous generations of kit. It’s no surprise that for most of us, hand-me-downs from universities, shrewd eBay purchasing, and even fruitful dumpster dives are a very viable way to attain useful and relevant test equipment. Now, while these acquisitions are more than adequate for the needs of a hobbyist lab, they are admittedly outdated and more to the point, inaccessible from a connectivity and communication standpoint. A modern lab has a very high degree of automated data acquisition and control over ethernet. Capturing screen dumps on a USB is a standard feature. These modern luxuries don’t exist on aging equipment conceived in the age of floppy disks and GPIB.
It was only last August that PJRC released Teensy 4.0. At that time, the 4.0 became the fastest microcontroller development board on the planet, a title it still holds as of this writing — or, well, not exactly. Today the Teensy 4.1 has been released, and using the same 600 MHz ARM Cortex M7 under the hood, is now also the fastest microcontroller board. What the 4.1 brings to the table is more peripherals, memory, and GPIOs. While Teensy 4.0 used the same small form factor as the 3.2, Teensy 4.1 uses the larger board size of the 3.5/3.6 to expose the extra goodies.
The now slightly older Teensy 4.0 — released on August 7th of last year — is priced at $19.95, with the new 4.1 version offered at $26.85. It seems that the 4.1 isn’t intended as a replacement for the 4.0, as they serve different segments of the market. If you’re looking for an ultra-fast affordable microcontroller board that lives up to its Teensy name, the 4.0 fits the bill. On the other hand, if you need the additional peripherals broken out and can afford the space of the larger board, the not-as-teensy-sized 4.1 is for you. How big is it? The sample board I measured was 61 x 18 mm (2.4 x 0. 7″), not counting the small protrusion of the micro-usb jack on one end.