One of the best things about USB C and lightning is how you can connect them both ways. Why aren’t all cables like this? HDMI, Ethernet, display port, USB A, etc. Why weren’t these ever designed to go in both ways from the get go? It seems like a simple thing.
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Not exactly really necessary. Desktop computer connections typically are very rarely removed/reconnected, so it’s not really a high priority
Many of the older ports that were digital were parallel ports. Meaning that each wire corresponded to a bit in a digit. If your flipped them, the order of the digits flip.
Some of the older displays were analog. So the wires were different colors, which posed the same issue flipping.
Old ports are wired to receive data on certain pins and transmit data on certain pins. If the receive and transmit pins are not lined up correctly information cannot be transferred. If it’s a powered cable like USB swapping your power and signal pins could potentially damage the device.
for older interfaces its due ot their physical wiring, their connection pins represent actual wires that are expected to match 1:1 with their approriate port match.
having the interface be strict like this is also helpful at simplyfying controller logic as it doesnt need ot check for multiple working states: it either plugged correctly, or it will not work.
Because it requires extra logic in the port controllers that needs to determine how the cable was plugged in. Much easier to create a port hole that’s non-symmetric and avoid the extra cost of electronics.
I think identification is one reason. Most people know what an hdmi cable looks, some other connection types might get confusing if they all just start having various shapes as connection points (square, rectangle, octagon etc)
Some need additional measures to making sure the connection doesn’t get broken requiring them to be keyed (network cable)
> It seems like a simple thing.
The six dangerous words that will make a programmer or engineer slap you silly.
Some wires (power, USB2.0) are just mirrored (so, you have up to twice the number of wires and twice as large connector needed). Other wires in the USB-C connector are far from that simple.
USB-C has wires inside it that the two end devices use to configure the connection, including detecting the orientation. Afterwards, the two devices have to each set up their own dedicated multiplexer switch chips to arrange the connections on their end of the cable to properly meet up with the rest of the USB circuitry.
TL;DR: There is a tiny computer inside USB ports whose job it is to untangle the connections in the reversible C plug.
Ports are designed for functionality. Back when, we used circular barrel plugs for the power plug (remember your old nokia phone) – because the functionality required it to be human interactable. However USB devices weren’t meant to be plug in and out on a frequent basis.
The reason why they weren’t done that way is because it costs more for such a design, in terms of $, labour, and electronics space.
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