Ubiquitous Successful Bus: Hacking USB 2 Hubs

November 5, 2024 by Arya Voronova 28 Comments

We’ve been recently looking into USB 2.0 – the ubiquitous point-to-point communications standard. USB 2 is completely different from USB 3, the blue-connector next-generation USB standard. For instance, USB 2 is a full-duplex pseudo-differential bus, and it’s not AC-coupled. This makes USB2 notoriously difficult to galvanically isolate, as opposed to USB 3. On the other hand, USB 2 is a lot easier to incorporate into your projects. And perhaps the best way to do so is to implement a USB hub.

USB 2 hubs are, by now, omnipresent. it doesn’t cost much to add to your board, and you truly have tons of options. The standard option is 4-port hubs – one uplink port to your host, four downlink ports to your devices. If you only have two or three devices, you might be tempted to look for a hub IC with a lower amount of ports, but it’s not worth bothering – just use a 4-port chip, and stock up on them.

What about 7-port chips? You will see those every now and then – but take a close look at the datasheet. Some of them will be two 4-port chips inside a single package, with four of the ports bottlenecked compared to the three other ports – watch out! Desktop 7-port hubs are basically guaranteed to use two 4-port ICs, too, so, again, watch out for bottlenecks. lsusb -t will help you determine the hub’s structure in case you don’t want to crack its case open, thankfully.

Recommendations? I use SL2.1 chips – they’re available in an SO16 package, very unproblematic, to-the-point pinout and easily hand-solderable. CH334 is a close contender, but watch out because there are different variants of this chip that differ by both package and pinout, so if you’re buying a chip with a certain letter, you will want to stick to it. Not just that, be careful – different variants run out at different rates, so if you lock yourself into a CH334 variant, consider stocking up on it. Continue reading “Ubiquitous Successful Bus: Hacking USB 2 Hubs” →

Printed Case Lets Pair Of RTL-SDRs Go Mobile

May 29, 2024 by Tom Nardi 24 Comments

We’ll admit to not fully knowing what [Jay Doscher] has planned for the pair of RTL-SDR Blog V4 software defined radios (SDRs) that are enclosed in the slick 3D printed enclosure he’s designed. But when has that ever stopped us from appreciating a nice design when we see one?

Inside the ventilated enclosure is the aforementioned pair of RTL-SDR Blog V4 (SDRs), as well as a StarTech USB hub that they’re plugged directly into. It seems like it wouldn’t take much to adapt this design to any other pair of USB gadgets, such as flash drives or WiFi adapters.

In fact, if they’re smaller than the RTL-SDR [Jay] has used here, you could probably get away with only needing to modify the one side panel of the case.

The simple modularity of the design, with two end pieces and the top and bottom plates, makes such modifications easy as you don’t need to reprint the whole thing if you just want a different antenna aperture. It also makes it easy to print without support material, and with just a few tweaks, looks like it could be adapted to use laser-cut panels for the sides. This would not only be faster than printing, but depending on the material, could make for a very stout enclosure.

We’ve covered several designs from [Jay] over the years, including a number of heavy-duty mobile “doomsday” computers that certainly fit in with this same design aesthetic. After all, why not face the end of the world with a little style?

OSHW Framework Laptop Expansion Hides Dongles

April 1, 2024 by Tom Nardi 16 Comments

If you’ve got a wireless keyboard or mouse, you’ve probably got a receiver dongle of some sort tucked away in one of your machine’s USB ports. While modern technology has allowed manufacturers to shrink them down to the point that they’re barely larger than the USB connector itself, they still stick out enough to occasionally get caught on things. Plus, let’s be honest, they’re kind of ugly.

For owners of the Framework laptop, there’s now a solution: the DongleHider+ by [LeoDJ]. This clever open source hardware project is designed to bring these little receivers, such as the Logitech Unifying Dongle, into one of the Framework’s Expansion bays. The custom PCB is designed with a large notch taken out to fit the dongle’s PCB, all you need to do is solder it in with four pieces of stiff wire.

Continue reading “OSHW Framework Laptop Expansion Hides Dongles” →

Flip The Switch On This I2C Controlled USB Hub

September 11, 2023 by Tom Nardi 13 Comments

You’ve probably seen USB hubs with physical switches for each port, they provide a handy way to cut the power to individual devices, but only if you’re close enough to flip them. They won’t do you much good if you want to pull the plug on a USB gadget remotely.

That’s why [Jim Heaney] created the I2C-USB-Hub. The device takes your standard USB 2.0 hub circuit, and adds in a MT9700 P-MOSFET load switch for each port. The enable pin on each of these switches is in turn connected to one of the output pins of a PCA9557PW I2C I/O chip. That means controlling each port is as easy as sending the proper sequence of bits over the wire, though [Jim] says he does plan on writing up an Arduino library to make flipping the digital switches a little more user friendly.

Since the 8-bit chip had a few extra pins left over, [Jim] wired one up to serve as a master control for the LED indicator lights on the PCB. Another is used to adjust the current limit on the MT9700 between 500 mA and 1 A.

While naturally we’re big fans of spinning up your own hardware here at Hackaday, we’ve also seen similar results achieved by modifying an off-the-shelf USB hub.

A small touchscreen displaying the Runbox GUI

Touchscreen-Powered USB Hub Selectively Powers Down Devices

December 6, 2021 by Robin Kearey 12 Comments

One of the most useful features of the Universal Serial Bus is its hot-plugging capability. You simply plug in your device, use it, and unplug it when you’re done. But what if you’ve got a huge number of USB devices? You might not want to use all of them all of the time, but repeatedly unplugging and re-plugging them is inconvenient and wears out the connectors. [Matt G] fixed this problem by building the RUNBOX: a USB hub that can be controlled through a touchscreen.

The USB hub part consists of a Yepkit YKUSH 3, which is a USB 3.1 hub that support software-controlled disconnecting of devices. [Matt] hooked up a Raspberry Pi to its ports so that it could switch devices on and off through a software command. To make it more user-friendly he added a touch screen controller and created an app using the Electron framework. This allowed him to enable or disable separate devices with a single touch: turn on the mic and webcam for video-conferencing, or fire up the VR headset and game controller for a gaming session.

The modified USB hub is housed in a laser-cut enclosure with plenty of space to hook up a variety of USB devices. The touchscreen neatly fits just above [Matt]’s keyboard; this setup was inspired by head-down displays used in aircraft which similarly use a small additional screen for peripheral functions.

Although we’ve seen switchable USB hubs before, they usually require you to either press a manual switch or run dedicated software on your PC. We’ve also seen other sleek builds combining a Raspberry Pi with a USB hub.

A Tiny USB Hub For All Your Hardware Modding Needs

February 2, 2020 by Tom Nardi 28 Comments

Going all the way hack to the heady days of Eee PC modding, hardware hackers have been on the hunt for small USB hubs that can easily be liberated from their enclosures and integrated into whatever project they happen to be working on. From time to time you see recommendations out there for makes and models which lend themselves to this sort of repurposing, but it’s seemed more difficult than necessary to source such a basic component.

Which is why [RETROCUTION] has developed a USB hub that’s not only extremely small, but relatively easy to assemble with only six components. Plus best of all, they are dirt cheap.

When you add up the cost of getting the PCBs made and buying all the SMD components, the per-unit price of these hubs is only going to be a few dollars. If you’ve got what it takes to make the PCBs in-house, even better. Considering how much easier these things could make other projects, it seems more than worth the upfront cost.

The star of the show is the FE1.1s, a four port USB 2.0 controller in a SSOP-28 package. As of this writing, it goes for about 25 cents from the usual overseas sources (even less, for larger orders). Add to the mix a few 10 μF ceramic capacitors, a 2.7 kΩ resistor, and a 12 MHz crystal.

There’s no provision for actual USB ports in the design, but they would just take up space anyway; this hub is intended to be directly soldered to the other devices. Incidentally, to reduce the number of traces and pads on the PCB, there aren’t power lines for the downstream devices either. So you’ll need to power them separately.

The passives are 0603, but the crystal is a good old fashioned through-hole component. [RETROCUTION] assembles the boards with a solder paste stencil and a hot air station, but if you’ve got a little practice, it’s certainly something you could do with an iron. With such a straightforward design, you could build a lifetime supply of these itty-bitty hubs in an afternoon. That’s certainly our plan, anyway.

Continue reading “A Tiny USB Hub For All Your Hardware Modding Needs” →

Keeping A 3D Printed NAS Updated With The Times

January 26, 2020 by Tom Nardi 28 Comments

Back in 2018, [Paul-Louis Ageneau] created a 3D printed network-attached storage (NAS) enclosure for his Raspberry Pi. The design worked well, the Internet liked it when he posted the details on his blog, and all was right with the world. But of course, such glories are fleeting. Two years later that design needs updating, and thanks to the parametric nature of OpenSCAD, he’s been able to refresh his design for another tour of duty.

In our book, this is as much a cautionary tale as it is a success story. On one hand, it’s a testament to the power of CAD and desktop 3D printing. That a design can be tweaked and reproduced down the line with only minimal hassle is great for folks like us. But it’s also a shame that he didn’t get more than two years before some of the parts he used in the original NAS became unobtainium.

The main issue was that the integrated USB hub he used for the first version is no longer available, so the design had to be modified to accept a similar board. Unfortunately, the new hub is quite a bit wider than the old one. Resizing the entire case isn’t really an option since the Pi has to slide into it, so the hub now bumps out a bit on one side. He’s added a printable cover that cleans it up a bit, but the asymmetrical look might be a problem for some. While fiddling with the design, he also changed around the cooling setup so a larger fan could be mounted; now that the Raspberry Pi 4 is out, it can use all the cooling help it can get.

We covered the original version of the printed NAS back when it was first released, and it’s always good to see a creator coming back and keeping a project updated; even if it’s because hardware availability forced their hand.