The messy transition to USB-C

Technology continues to march forward. Back when I started using a computer printers and other peripherals used a variety of different cables, connectors and standards to communicate. We had serial ports, parallel ports, SCSI, DIN connectors, Apple Serial Bus, FireWire 400 and 800, and bunch of others that appeared and disappeared. We even had cards that inserted such as PCMCIA, PC Card and others that were meant to make it easier for use to add functionality to our computers.

Then, in 1990s, we saw the arrival of USB. The promise was that this one connector could replace all the others. Since then, we have been on that journey to have the one port that rules them all.

How USB was (and kind of still is)

The proponents of USB told us that this one connector and the associated communications standards it supports (more on that later) would be able to not only carry data from peripherals to our computers but also deliver power so it could be used to charge other devices. And it did this pretty well for over 20 years.

For most of that time, we only saw a limited number of USB connectors on cables. USB-A is the rectangular connector that we usually plug into a computer. Then there are some smaller connectors that typically go into peripherals. These were dubbed mini-USB and micro-USB. There’s also USB-B which is a squarish connector that was often used with printers.

While the number of different connectors was a pain, the world more or less consolidated on USB-A at one end and micro-USB at the other for most peripherals. And this was how most hardware makers, other than Apple and its love for proprietary connectors like Lightning, did things.

What prompted a change?

In short, people wanted to move more data, faster than ever before. And that wasn’t just stuff like files, images and videos – HDMI evolved so streaming content could be sent from our computers onto screens. That lead to the development of DisplayPort and Apple’s preferred version of that standard, Mini DisplayPort. The obvious solution to making life easier for consumers was to find a way to consolidate all these into a single standard.

USB-C became that standard. Well, it should have but it’s turned into a massive confusopoly. And the reason for that is that while most of us focus on the connector and expect something that plugs in to work, there’s much more this than meets the eye.

The USB-C connector is just a connector

The USB-C connector that replaces all the previous USB connectors is only one part of the puzzle. USB-C is incredibly versatile. It can carry almost any type of data that your computer can throw at it. You can connect a monitor to your Mac, iPad or iPhone using USB-C (and a Lightning adaptor for some devices). You can connect an external hard drive. Or a scanner. Or a microphone. Or a webcam.

But that connector doesn’t work in isolation. It is part of a more complex system. For example, a cable that has USB-C connectors at both ends might be good for charging a device but isn’t capable of connecting a computer to an external display. That’s because the connector is only part of the story.

The other part is standards that govern communication rates. These are recognisable as they use numbers rather than letters.

Standard	Connector Types	Max. Data Transfer Speed
USB 1.1	USB-A  USB-B	12 Mbps
USB 2.0	USB-A  USB-B  USB Micro A  USB Micro B  USB Mini A  USB Mini B  USB-C	480 Mbps
USB 3.2 Gen 1	USB-A  USB-B  USB Micro B  USB-C	5 Gbps
USB 3.2 Gen 2	USB-A  USB-B  USB Micro B  USB-C	10 Gbps
USB 3.2 Gen 2×2	USB-C	20 Gbps
USB 4	USB-C	20 Gbps
USB 4	USB-C	40 Gbps

What you can see from this is that USB-C connectors can be used by a number of different USB communications standards. But, looking at a cable or connector, it’s almost impossible to tell if a cable with a USB-C connector is limited to USB 2.0 or if it will work with USB 3.2.

Some real world challenges

We have an Asus laptop in the house with a USB-C port and a USB-C powered portable monitor. If I connect the monitor directly to the laptop it will not display an image. But if I connect the same monitor, using the same cable to my iPad Pro, it works just fine.

If we look at that scenario, without delving deep into the specs of the laptop, there’s no way of knowing that its USB-C port is not capable of sending video to that monitor (which as worked with a number of other devices and not just the iPad Pro).

Similarly, there are USB-C cables that are good for charging devices but can’t carry any data at all. Or some that can carry data but have a limited capacity for charging a device. If you search Amazon for a USB-C cable, you’re almost certainly spinning a roulette wheel to get a cable that does what you expect or want.

When you look at that table, it’s easy to see where the confusion comes from. The USB-C connector is backwards compatible with USB 2.0 – a standard that was established in 2000. While backwards compatibility is a useful thing, if the USB-C connector had been tied to USB 3, then we could have created assurance that a cable with USB-C connectors could carry power, data and video without the need to remember a bunch of standards.

And, remember, as USB-C can be used to charge devices it’s possible that a cable could look right but cause charging problems. It’s worth noting that the European Union is mandating that all mobile accessories use USB-C in order to reduce electronic wastage caused by the use of proprietary cables such as Apple’s Lightning.

What can you do?

I never kept track of USB cables in the past. Before USB-C came along, I was confident that whichever cable I grabbed from the draw would work. There was the odd exception (I had a voice recorder that was very finicky about which cable I used to transfer recordings to my Mac) but that was pretty rare.

With USB-C, when I buy an accessory, I label the cable so I know what it works with. For example, the USB-C portable monitor I have and its cable are never separated.

When buying USB-C cables, pay close attention to the exact specification of the cable. The table above is a useful reference. And buy from a reputable source. While that $3 cable on Amazon may be cheap, it’s wasted money if it doesn’t do what you want. And it’s a bigger pain if it’s not been made correctly and causes damage to a device. There are many reports of cables that have the right connectors on the ends but have not been wired correctly and have caused problems.

All of this leads us to one conclusion. While USB-C can be the one connector to replace them all, the way it has been brought to market has lacked direction and clarity. For over 20 years, we were trained to understand that once a USB cable was plugged in that it would work. USB-C, with its confusing link to different USB communications standards has changed the game.