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To connect two USB-A ports.
Basically the same as a USB-A to USB-A cable, just really short.
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.
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.
USB-A to USB-A cables do not exist
wtf are you talking about, of course they do.
They meant cables in spec with the USB specification at the time usb-a was new.
Now with usb-c, it's kinda moot, as most cables are male to male anyway.. of course that means we're more likely to see USB-C female to female adopters now
USB-C female to female adapters also are out of spec. The USB standard does not allow for extensions. USB cables only have male connectors (with the exception of USB-OTG dongles).
Show me where in the USB standards these are specified.
This is like saying that a building isn't a building if it's not up to code
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.
But those are actually part of the standard.
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.
You can find compliance requirements in the document linked here: https://www.usb.org/document-library/usb-type-c-connectors-and-cable-assemblies-compliance-document
You want to look at table 3-6 for requirements for USB-C to legacy USB adapters.
USB-A to USB-A cables do exist.
I have seen many (very cheap) peripherals use USB-A sockets. I figure those sockets must be a few cents cheaper than alternatives.
And there was a USB certified logo on these cables and devices?
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.
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.
USB-A to USB-A doesn't exist
*looks at old charger from an American device*
HOLY SHIT A CRYPTID CALL SCP
That’s not a USB charger.
HOLY SHIT AN UNIDENTIFIED CRYPTID CALL SCOOBYDOO!
They do exist, despite the USB standards not allowing them
See: cheapo video capture card for work, other side is just HDMI-IN and OUT
They shouldn't exist but don't mean they don't when you get the cheapest little devices you can find
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.
