PoE-powered GPIB Adapter With Ethernet And USB-C Support

May 10, 2025 by 9 Comments

In the world of (expensive) lab test equipment the GPIB (general purpose interface bus) connection is hard to avoid if you want any kind of automation, but nobody likes wrangling with the bulky cables and compatibility issues when they can just use Ethernet instead. Here [Chris]’s Ethernet-GPIB adapter provides an easy solution, with both Power over Ethernet (PoE) and USB-C power options. Although commercial adapters already exist, these are rather pricey at ~$500.

Features of this adapter include a BOM total of <$50, with power provided either via PoE (802.3af) or USB-C (5V-only). The MCU is an ATmega4809 with the Ethernet side using a Wiznet W5500 SPI Ethernet controller. There is also a serial interface (provided by a CH340X USB-UART adapter), with the firmware based on the AR488 project.

The adapter supports both the VXI-11.2 and Prologix protocols, though not at the same time (due to ROM size limitations). All design documents are available via the GitHub repository, with the author also selling assembled adapters and providing support primarily via the EEVBlog forums.

Wireless USB Autopsy

May 7, 2025 by 22 Comments

It might seem strange to people like us, but normal people hate wires. Really hate wires. A lot. So it makes sense that with so many wireless technologies, there should be a way to do USB over wireless. There is, but it really hasn’t caught on outside of a few small pockets. [Cameron Kaiser] wants to share why he thinks the technology never went anywhere.

Wireless USB makes sense. We have high-speed wireless networking. Bluetooth doesn’t handle that kind of speed, but forms a workable wireless network. In the background, of course, would be competing standards.

Texas Instruments and Intel wanted to use multiband orthogonal frequency-division multiplexing (MB-OFDM) to carry data using a large number of subcarriers. Motorola (later Freescale), HP, and others were backing the competing direct sequence ultra-wideband or DS-UWB. Attempts to come up with a common system degenerated.

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Adding An Atari Joystick Port To TheC64 USB Joystick

April 24, 2025 by 1 Comment

“TheC64” is a popular recreation of the best selling computer of all time, the original Commodore 64. [10p6] enjoys hacking on this platform, and recently whipped up a new mod — adding a 9-pin Atari joystick connector for convenience.

When it comes to TheC64 units, they ship with joysticks that look retro, but aren’t. These joysticks actually communicate with the hardware over USB. [10p6]’s hack was to add an additional 9-pin Atari joystick connector into the joystick itself. It’s a popular mod amongst owners of TheC64 and the C64 Mini. All one needs to do is hook up a 9-pin connector to the right points on the joystick’s PCB. Then, it effectively acts as a pass-through adapter for hooking up other joysticks to the system.

While this hack could have been achieved by simply chopping away at the plastic housing of the original joystick, [10p6] went a tidier route. Instead, the joystick was granted a new 3D printed base that had a perfect mounting spot for the 9-pin connector. Clean!

We’ve seen some great hacks from [10p6] lately, like the neat reimagined “C64C” build that actually appears in this project video, too.

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Hacking A Cheap Rechargeable Lamp With Non-Standard USB-C Connector

April 12, 2025 by 40 Comments

Recently [Dillan Stock] bought a $17 ‘mushroom’ lamp from his local Kmart that listed ‘USB-C rechargeable’ as one of its features. Unfortunately while this is technically true, there’s a pretty major asterisk. This Inaya-branded lamp comes with a USB-C cable with a rather prominent label attached to it that tells you that this lamp requires that specific cable. After trying with a regular USB-C cable, [Dillan] indeed confirmed that the lamp does not charge from a standard USB-C cable. So he did what any reasonable person would do: he bought a second unit and set about to hacking it.

The "USB C" cable that comes with the Inaya Portable Rechargeable Lamp. (Credit: The Stock Pot, YouTube)
The “USB C” cable that comes with the Inaya Portable Rechargeable Lamp. (Credit: The Stock Pot, YouTube)

[Dillan] also dug more into what’s so unusual about this cable and the connector inside the lamp. As it turns out, while GND & VCC are connected as normal, the two data lines (D+, D-) are also connected to VCC. Presumably on the lamp side this is the expected configuration, while using a regular USB-C cable causes issues. Vice versa, this cable’s configuration may actually be harmful to compliant USB-C devices, though [Dillan] did not try this.

With the second unit in hand, he started hacking in earnest. The changes include a regular USB-C port for charging, an ESP32 board with integrated battery charger for the 18650 Li-ion cell of the lamp, and an N-channel MOSFET to switch the power to the lamp’s LED. He’s made the full plans and schematics available on his website.

With all of the raw power from the ESP32 available, the two lamps got integrated into the Home Assistant network which enables features such as turning the lamps on when the alarm goes off in the morning. All of this took about $7 in parts and a few hours of work.

Although we commend [Dillan] on hacking his device instead of just returning it to the store, it’s worrying that apparently there’s now a flood of ‘USB C-powered’ devices out there that come with non-compliant cables. It brings back fond memories of hunting down proprietary charging cables, which was the issue that USB power was supposed to fix.

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Why USB-C Splitters Can Cause Magic Smoke Release

April 7, 2025 by 40 Comments

Using USB for powering devices is wonderful, as it frees us from a tangle of incompatible barrel & TRS connectors, not to mention a veritable gaggle of proprietary power connectors. The unfortunate side-effect of this is that the obvious thing to do with power connectors is to introduce splitters, which can backfire horribly, especially since USB-C and USB Power Delivery (USB-PD) were introduced. The [Quiescent Current] channel on YouTube recently went over the ways in which these handy gadgets can literally turn your USB-powered devices into a smoldering pile of ashes.

Much like Qualcomm’s Quick Charge protocols, USB-PD negotiates higher voltages with the power supply, after which this same voltage will be provided to any device that’s tapped into the power supply lines of the USB connector. Since USB-C has now also taken over duties like analog audio jacks, this has increased the demand for splitters, but these introduce many risks. Unless you know how these splitters are wired inside, your spiffy smartphone may happily negotiate 20V that will subsequently fry a USB-powered speaker that was charging off the same splitter.

In the video only a resistor and LED were sacrificed to make the point, but in a real life scenario the damage probably would be significantly more expensive.

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Multifunctional USB controlled PCB on blue background

How A Tiny Relay Became A USB Swiss Army Knife

April 5, 2025 by 17 Comments

Meet the little board that could: [alcor6502]’s tiny USB relay controller, now evolved into a multifunction marvel. Originally built as a simple USB relay to probe the boundaries of JLCPCB’s production chops, it has become a compact utility belt for any hacker’s desk drawer. Not only has [alcor6502] actually built the thing, he even provided instructions. If you happened to be at Hackaday in Berlin, you now might even own one, as he handed out twenty of them during his visit. If not, read on and build it yourself.

This thing is not just a relay, and that is what makes it special. Depending on a few solder bridges and minimal components, it shape-shifts into six different tools: a fan controller (both 3- and 4-pin!), servo driver, UART interface, and of course, the classic relay. It even swaps out a crystal oscillator for USB self-sync using STM32F042‘s internal RC – no quartz, less cost, same precision. A dual-purpose BOOT0 button lets you flash firmware and toggle outputs, depending on timing. Clever reuse, just like our mothers taught us.

It’s the kind of design that makes you want to tinker again. Fewer parts. More function. And that little smile when it just works. If this kind of clever compactness excites you too, read [alcor6502]’s build log and instructions here.

PPS Is The Hottest USB-C Feature You Didn’t Know About

March 24, 2025 by 28 Comments

USB Power Delivery is widely considered to be a good thing. It’s become relatively standard, and is a popular way for makers to easily power their projects at a number of specific, useful voltages. However, what you may not know is that it’s possible to get much more variable voltages out of some USB chargers out there. As [GreatScott!] explains, you’ll want to meet USB-C PPS.

PPS stands for Programmable Power Supply. It’s a method by which a USB-C device can request variable voltage and current delivery on demand. Unlike the Power Delivery standard, you’re not limited to set voltages at tiers of 5V, 9V, 15V and 20V. You can have your device request the exact voltage it wants, right from the charger.  Commercially, it’s most typically used to allow smartphones to charge as fast as possible by getting the optimum voltage to plumb into the battery. However, with the right techniques, you can use PPS to get a charger to output whatever voltage you want, from 3.3 V to 21 V, for your own nefarious purposes. You can choose a voltage in 20 mV increments, and even set a current limit in 50 mA increments. Don’t go mad with power, now.

However, there’s a hitch. Unlike USB PD, there isn’t yet a whole ecosystem of $2 PPS breakout boards ready to gloop into your own little projects. As [GreatScott!] suggests, if you want to use PPS, you might want to take a look at the AP33772S IC. It’s a USB PD3.1 Sink Controller. You can command it over I2C to ask for the voltage and current you want. If that’s too hard, though, [CentyLab] has a solution on Tindie to get you going faster. It’s also got some exciting additional functionality—like USB-C AVS support. It offers higher voltage and more power, albeit with less resolution, but chargers with this functionality are quite obscure at this stage.

We’ve actually touched on PPS capability before in our exploration of the magic that is USB-C Power Delivery. Video after the break.

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