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Will a USB-C Adaptor; fit into what Apple calls the USB 3 port on the new iMac 2021

Will a USB-C Adaptor; fit into what Apple calls the USB 3 port on the new iMac 2021? The port looks like it will only accept a USB-C.


Perplexed why Apple calls it a USB 3 port if one uses a USB -C dongle.

Posted on Jun 16, 2021 10:18 AM

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Posted on Jun 16, 2021 11:07 AM

Actually, Apple's own website refers to it as "USB 4" in conjunction with it being a Thunderbolt port. By the photo alone, one can visually identify them as USBc ports.


It's a little confusing, especially when "Thunderbolt" is mixed in. USB4/Thunderbolt is a protocol. USBc is a physical port.


USB4 is compatible and interchangeable with any prior flavors of USB, including USB3.1, USB2, and so on. The USB3 ports while slower than USB4, can still connect to slower USBA devices. It's just that those require require an adapter - as you noted - to plug a physical USBA device to the iMac's physical USBc port.

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Jun 16, 2021 11:07 AM in response to raspberryaddiction

Actually, Apple's own website refers to it as "USB 4" in conjunction with it being a Thunderbolt port. By the photo alone, one can visually identify them as USBc ports.


It's a little confusing, especially when "Thunderbolt" is mixed in. USB4/Thunderbolt is a protocol. USBc is a physical port.


USB4 is compatible and interchangeable with any prior flavors of USB, including USB3.1, USB2, and so on. The USB3 ports while slower than USB4, can still connect to slower USBA devices. It's just that those require require an adapter - as you noted - to plug a physical USBA device to the iMac's physical USBc port.

Jun 16, 2021 11:25 AM in response to raspberryaddiction

Do not entirely blame Apple for this one.


<rant>

The confusion stems from the USB Consortium (the council that defines and maintains the official USB specification). They have consistently messed up when it comes to clarity around USB-A, USB-B, USB-C, mini-USB, micro-USB (which are all physical port definitions) and USB1/USB2/USB3/USB3.1/USB3.2/USB4 (which are all protocol definitions).


They will say it's done in the name of backwards compatibility, but you almost need a Phd in astrophysics to understand the logic behind which physical/logical combinations actually work (not to mention the lack of clarity around cable standards (not all USB-C cables are created equally, but there is ZERO way to know this by looking at the cable).


In this case, ALL your ports are USB-C (the physical definition). SOME support USB-3(.1), SOME support USB4.

</rant>

Will a USB-C Adaptor; fit into what Apple calls the USB 3 port on the new iMac 2021

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