USB Everywhere All At Once
Introduction
With the arrival of USB C and the final collapse of the last corporate resistance to the standardization of digital interconnection, it is instructive to reflect on the evolution of these connectors and their electrical and signaling standards going back at least to the 1960s.
My first experience with remote computing connections came when I was in high school. Our school established a relationship with a time sharing operator and situated a Teletype Model 33 ASR device in a small windowless room in the high school. The device connected by telephone and acoustic coupler to the remote computer and we wrote and ran programs in BASIC.
The interconnection between the modem and the teletype was a bundle of wires presented through a DB-25 connector.
This connector was referred to at the time as a "D Subminiature," a designation that may have made sense to the engineers who developed it but that is now viewed with hilarity.
What was fascinating at the time was that the teletype devices actually used only two or perhaps three of the pins on the connector to carry the RS-232 signals. In the 1980s the connector was used to connect printers to early PCs, and in that application did use more than two or three pins.
Problems and annoyances
These connectors were big and heavy and inefficient, particularly because so few of the pins were actually used. As computing moved from big deskside towers to smaller and smaller laptops, engineers, and customers, demanded smaller connectors.
In addition, consumers were frustrated with the proliferation of oddly shaped and mutually incompatible connectors required to take advantage of their new digital devices. These connectors were used variously to power and interconnect devices.
And then cell phones became smaller yet and we discovered that it was useful to connect our phones to our laptops.
Enter USB
USB first entered the market in 1996, though it did not start making significant commercial headway until two years later.
USB was designed strictly for connecting one host to one device. It was not for host-to-host connections, though it has been adapted for that in recent times.
In the beginning the connectors were big and clunky. There was one end for the host computer, called Type A, …
and one for the device, called Type B.
The original Type B connector was too big for anything portable, so as near as I can tell it is only used to connect to printers. Of course, most printers connect to the network these days, so the classic Type B connectors are mostly vestiges.
Smaller Type B connections arrived to help address the need to support ever smaller devices - the mini and the micro in particular became quite popular.
Both the Mini B and the Micro A are intended to connect to devices, not hosts, so why the Micro is identified as "Micro A" and not "Micro B" is a mystery to me.
Symmetry shmimmitry
Meanwhile, Apple used a proprietary connector called Lighning for the iPhone and iPad devices.
One distinctive advantage that the Lightning connector had over the USB Micro was that it could be attached in either orientation, whereas all of the USB connections had a definite "up" and "down" that had to be honored.
With the tiny sockets on phones and other small devices, it was hard to determine the orientation, particularly in a darkened room at bedtime, resulting in the annoying experience of trying to plug in the connector and failing, not being sure whether you had it upside down or if you simply did not get alignment right.
Various jurisdictions demanded that all host and device makers adopt "standard" connectors and cables, but Apple demurred, despite threats of fines and public defenestrations.
Enter USB C
Finally, USB C arrived. For the first time there was a USB device-end connector that could be plugged in either way 'round and it would just work!
And no sharp edges to cut your fingers, either!
(USB connector images from https://www.cablestogo.com/learning/connector-guides/usb)
After USB C was established, Apple finally relented and started offering phones that accepted USB C instead of Lightning.
The aftermath
I have lots of little plastic bags with USB cables in them. Each one has an index card in it with markings to identify the kind of cable inside: "A to Micro," "A to B," "A to C," "C to C," and so on. There are a variety of devices that I connect with USB cables:
1 - Rechargeable batteries ("power banks") that I carry to replenish my phone's battery in emergency:
2 - Multiport USB chargers to let me recharge multiple devices all at once:
3 - Portable devices (phones and tablets)
4 - Computers (desktops and laptops)
5 - Peripheral gadgets
Speakers
Webcams
Backup disks
Newer devices come with Type C connectors, but older ones come with a built-in cable ending in a Type A connector or expect a Micro A or Mini B connector from the host.
Until I have refreshed my collection of gadgets, I will need regularly to have adapters like this, allowing me to connect a Type A male connector to a Type C plug on a host.
I already have a dusty collection of Type-A-to-Micro cables that I almost never use any more. Whenever a family member asks to borrow one, I tell them not to bother returning it. Sadly, they seem to have figured out that these cables are a drug on the market and return them assiduously.
Recently I had to purchase a bunch of Type-C-to-Type-C cables, since they seemed to be in short supply in my household.
Someday I predict that all I will have is Type-C-to-Type-C and Type-A-to-Type-C, but I don't know how long that will take.
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