USB-A to USB-A cables do not exist, the USB standard does not allow them, if you have a cable with two USB-A connectors then it’s not actually a certified USB cable. The same goes for USB extension cables and this adapter. Note how there isn’t a ‘USB certified’ logo on the package.
Or like saying usb-a to usb-c adapters don’t exist because they’re not part of the standard but we all have like six of those damn things even though we’ve never actually bought a single one.
Are they? Everything I can find seems to say they aren’t.
I remember when the first usb-c Macbooks hit stores Apple didn’t have usb-a to c adapters for sale because they weren’t in spec, a lot of reviews mentioned that.
The cables exist; they just don’t follow the standard. I’ve used them when developing consumer electronics: the host controller on the device switches to device mode in the bootloader, allowing a host machine to connect and debug/flash the device.
China stuff loves to slap logos on there that do not apply, so probably without having seen this particular abomination myself. Fake CE markings are super common though.
They do exist, despite the USB standards not allowing them
A USB cable is a cable that conforms to the USB specification. If a cable does not conform to the USB specification then it isn’t an USB cable by definition
I’m not saying a cable with 2 USB-A style connectors doesn’t exist, I’m just saying that it is not a USB cable. Just like a glass of Pepsi is not a glass of Coca-Cola even though it may look like one.
It’s not hard to imagine a product that would require one, though. It’s how every phone charging cable works, just with a different size male USB on one end.
It’s how every phone charging cable works, just with a different size male USB on one end.
No, it’s exactly not how every phone charging cable works, at least not for non USB-C cables.
Pre-USB-C cables are explicitly unidirectional. In USB there are ‘hosts’ (usually computers) and ‘devices’ (flashdrives, camera’s, mice, keyboards, etc.). The host side always has a female USB-A connector, a device either has a female USB-B connector (if it’s intended to be used with a cable), or a male USB-A (if it’s intended to be plugged in directly into a host, like a flash drive). A real, standard-conformant USB cable can only go from USB-A male to USB-B male (with the addition of USB-C, it can also go from A-to-C, from C-to-B, or C-to-C). Never A-to-A or B-to-B, extension cables (male to female) of any type, A, B or C, are not allowed either.
USB was specifically designed like this so you can never connect a device to a device or a host to a host.
On the host side, you pretty much only see full size USB-A ports. On the device side there are 3 common types of USB-B ports: standard size (you can for example see these on printers and scanners), mini-USB-B used a lot on older phones, and later micro-USB-B. On each side the male part is on the cable, the female part is on the host or device.
Such A-to-A adaptors and cables always have been prohibited by the USB spec, but people built them anyway. A common usecase for “illegal” A-A cables i remember was connecting PCIe cards (especially GPUs and mining cards) externally to riser sockets.
I bought a breadboard power supply and the options to feed it power are a barrel jack and usb-a. Considering the size of the thing mini or micro would have made way more sense.
The ones I have go trough the onboard voltage regulator and you can use them to power USB-devices. I suppose they’ve skipped diodes and other protective components so it can feed back to the circuit, but I haven’t tested that.
So you have 2 USBC devices you want to connect together, a laptop and a phone for example, but for some reason you can’t find your USBC to USBC cable but you do have 2 USBC to USBA cables.
Well by breaking the USB specifications you can connect the 2 cables together to make a janky USBC to USBC cable.
Alternatively you can get single circuit boards with USBA ports on them and you can use this jank of an adaptor to link them together.
I have a cheap HDMI capture device that takes in video input, exposes it to the computer as a regular webcam, and then outputs it back to HDMI. It gets the job done.
It uses an USB male to male for power, and a regular one for data.
That said, not sure how a short one like that would help.
I actually have a APC UPS at work that uses a USB-A to USB-A cable. You can look up the cable online, it's part number 940-0504. I was surprised APC used such a cable. I think if you tried to do something dumb like connect two PCs together with it, one of the USB ports would fry.
Not that you probably need to know this, but for some other stranger: there’s a max functional length to USB cables. At work I remember pulling my hair out troubleshooting a printer until we swapped cables for something shorter.
He said printer though that’s what’s what threw me off. That’s a cutter. My bad I thought he was talking about a USB large format printer, I only replied because I’m looking for a slightly smaller printer for my smaller decals, and I’d be interested in a serial or USB printer.
My PC is in the basement and I’ve got USB and serial going everywhere running different cutters, 3d printers, CNC, etc upstairs and down, also in the garage. Works great.
We have smart boards in most classrooms, but in an entire wing of my department the smart board doesn’t work. Reason? When we built the wing, 8 or 10 years ago, the installers fitted their own low grade plugs on the USB connection for the boards, before figuring out that they snipped the cables too short. Instead of running new cabling the installers then introduced another extension.
Nobody cared to check it out before accepting delivery and my complaints went unheard by management, until it was too late to RMA it.
Not one that short but I do have A to A cord like that in use. In my case it’s with a KVM that I lost and AC adapter for but found that if I plugged in to one of the rear console connections it could get it to power on from the USB device. Cable it to a USB charging port on the front of one of the UPS and away it goes.
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