2317: Pinouts

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Pinouts
The other side of USB-C is rotationally symmetric except that the 3rd pin from the top is designated FIREWIRE TRIBUTE PIN.
Title text: The other side of USB-C is rotationally symmetric except that the 3rd pin from the top is designated FIREWIRE TRIBUTE PIN.

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: Created by a FIREWIRE TRIBUTE PIN. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.
If you can address this issue, please edit the page! Thanks.

Connecters are designed to transport both data and power. Each pin on a connecter can only carry either 1 bit at a time or 1 voltage of power. In this comic there is an absurd alternative to the actual pins used in connecters


HDMI

Label Explanation
Data TODO
+5V Many actual pin configurations use +5 volts to supply power to a device.
+6VI V is usually used to represent volts, but here, VI represents the Roman numeral 6.
+7VII V is usually used to represent volts, but here, VII represents the Roman numeral 7, continuing the pattern from above.
Antidata TODO
Water TODO
Vacuum TODO
Amazon Copyright Pin TODO
Decorative TODO
+3.3V DC TODO
-3.3V DC TODO
Tx TODO
Wx TODO
Rx Only TODO
Unknown TODO
+240V DC TODO
5V AC TODO
GND GND typically refers to "ground" on pinout diagrams.
Ground Compared to the above pin, this appears to be the same ground pin. However, the presence of both GND and Ground seems to imply that GND represents something other than the standard "ground" pin.

Micro USB

A ground pin is commonly found on USB and other pin connectors. However, it generally serves no data purpose. Therefore, it seems rather silly for the micro USB to have 5 ground ports and only 1 functional "USB" port. It also does not give much information about what the "USB" port would do, as opposed to a standard pinout diagram.

Label Explanation
GND TODO
GND TODO
GND TODO
USB TODO
GND TODO

USB-C

Label Explanation
+5V DC TODO
+3.3V DC TODO
+120V AC TODO
Boobytrap Pin (Pure Solder) TODO
Mechanical TODO
+3.3eV/C TODO
Candlepin TODO
Facebook Use TODO
+5V (Positrons) TODO
Pin Roulette TODO
GND TODO
SKY Reference to the ground pin, which refers to the common grounding on the larger metal body. There is no corresponding "sky" pin, although sky is often thought as the opposite of ground.

Coax

Label Explanation
Pin A coax connector only has one conductive part; while it may satisfy the standard definition of a "pin", this is not a useful label.

Transcript

[Caption at top]
Pinouts
Quick Reference Guide
[Four common connectors are depicted - vertically, rather than the usual horizontal orientation.]
[The first connector is a 19-pin HDMI connector.]
[The nine pins on the left are labeled:]
  • Data
  • +5V
  • +6VI
  • +7VII
  • Antidata
  • Water
  • Vacuum
  • Amazon Copyright Pin
  • Decorative
[The ten pins on the right are labeled:]
  • +3.3V DC
  • -3.3V DC
  • Tx
  • Wx
  • Rx Only
  • Unknown
  • +240V DC
  • 5V AC
  • GND
  • Ground
[The second connector is a 5-pin Micro USB connector.]
[The five pins are labeled:]
  • GND
  • GND
  • GND
  • USB
  • GND
[The third connector is a 24-pin USB-C connector, with only the right side labeled.]
[The twelve pins on the right are labeled:]
  • +5V DC
  • +3.3V DC
  • +120V AC
  • Boobytrap Pin (Pure Solder)
  • Mechanical
  • +3.3eV/C
  • Candlepin
  • Facebook Use
  • +5V (Positrons)
  • Pin Roulette
  • GND
  • SKY
[The fourth and final connector is a 1-pin COAX connector.]
[The one pin in the center is labeled:]
  • Pin


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Discussion

Can we add this one to a new category, "Comics that Randall makes just to screw with xkcd wiki contributors"? I can think of plenty of candidates for this category! Cosmogoblin (talk) 21:42, 8 June 2020 (UTC)

Wouldn't be more useful to make a category for comics that Randall DOESN'T make to screw with xkcd wiki contributors? Might be smaller ... -- Hkmaly (talk) 22:26, 10 June 2020 (UTC)

The claim that a coax has only one conductive part is incorrect. It has two. The pin is the inner conductor. The shield is the outer conductor. Without both it wouldn't work.

yes, but it's a "pin" out. Hence, "pin" WhiteDragon (talk) 21:37, 9 June 2020 (UTC)

I'd also say that the claim at the top that a pin can have only one bit or one voltage of power at a time is incorrect. Power over Ethernet is a perfect example of power and data at the same time. There are also plenty of types of signals which transmit multiple bits at once. A simple example would be a signal using four voltage levels to transmit two bits simultaneously, but there are many more fancy analog encodings that use phase and frequency and other characteristics to transmit data. Plus, you can often included two signals on the same conductors. For example, ADSL combined a normal phone signal and a higher frequency data signal on the same lines. Also cable TV combined many signals on one set of conductors.

So, anyway, I'd remove the claim. Mootstrap (talk) 23:00, 8 June 2020 (UTC)

Just because it’s interesting: DCC with RailCom+ allows some cool stuff. It allows many-to-many high-power power transmission, robust many-to-many bidirectional data transmission, hot-swap with automatic configuration and collision resolution, physical position tracking of the connected devices, some way of short-circuit resolution with continued communication, mixing with other protocols, and all with only two pins, which may be arbitrarily interchanged at any time. Admittedly it has a much lower data rate than Power over Ethernet and terrible EMI, but potentially much higher power. 162.158.89.193 08:22, 9 June 2020 (UTC)

For that matter, the RF cable connecting a regular TV antenna, or the wire in a car that connects the radio antenna, carries the signals of all the channels.172.69.33.65 02:20, 9 June 2020 (UTC)

I think "Pin Roulette" is a pun on Penn Jillette, the talkative half of the Penn & Teller magic act, and maybe also a reference to chatroulette. Barmar (talk) 23:10, 8 June 2020 (UTC)

Possible, but I'd stick with the simple explanation - that the "Pin Roulette" pin selects a random function when the connector's plugged in. 108.162.245.64 23:18, 8 June 2020 (UTC)
Modern conectors additionally tend to have multi-purpose pins, which might be dangerous if you guess the current meaning of the pin wrong.Gunterkoenigsmann (talk) 06:15, 9 June 2020 (UTC)

In addition to pins being able to carry both data and power, or to carry multiple bits at a time, some pins function as clock signal pins that indicate bit boundaries rather than themselves carrying data; therefore I also think the claim should be either omitted or changed entirely. Vaedez (talk) 23:33, 8 June 2020 (UTC)

Firstly, no Soup? Secondly, GNDN might easily have been referenced. Thirdly, would a pin made of solder melt, as pins connected to wires/boards by solder do not melt the solder (under proper range of use). 141.101.107.158 23:38, 8 June 2020 (UTC)

i think the implication is that it could melt, which is a trap--Vaedez (talk) 23:48, 8 June 2020 (UTC)

Perhaps we should add the actual usage of the pins to help those who actually want to know? 162.158.62.245 00:08, 9 June 2020 (UTC)

Wouldn't 3.3eV/C be a tiny fraction of 3.3V, since a columb is a much greater value of charge than that of the electron?--172.69.63.203 00:24, 9 June 2020 (UTC)

Depending on how you read it, the third pin from the top might match the 120V AC. This would make it a different kind of "tribute" to FireWire... EHusmark (talk) 07:52, 9 June 2020 (UTC)

AFAIK FireWire allows many-to-many communication, while USB never did. The FireWire tribute pin could be a way to establish many-to-many communication. Alternatively, FireWire allows daisy-chaining, while USB supports only a tree network trough hubs. The FireWire pin could be somehow physically strange, so a second USB-C cable could be connected to it. 162.158.89.193 08:22, 9 June 2020 (UTC)

The "FireWire tribute pin" bit actually probably was intended to be about the 110V pin. Providing 110V is, of course, absurd, but FireWire was (I think) the first computer bus to use a relatively high bus voltage to send lots of power over the wire. The spec actually requires hardware to handle up to 30 VDC. In fact, I once heard lore about an early prototype PowerMac G4 (I think) that was nicknamed "FireBurner". Apple built it at one point in the distant past, and actually provided 30V worth of bus power. They didn't ship that configuration to the public as far as I know, but they used to make it available to companies who wanted to test their FireWire hardware for compatibility. Unfortunately, a lot of hardware manufacturers in the early days didn't pay attention to that 30V number and assumed that the hardware would always provide 12V like the Macs that had shipped up to that point. When they actually encountered 30V, a lot of those early devices didn't survive. Dgatwood (talk) 19:49, 6 August 2020 (UTC)

Added a little more description to the coax cable section, just in case it wasn't obvious to a layman what an example of the cable would be or why it was included with a cartoon about digital data cables.--172.69.68.195 22:46, 10 June 2020 (UTC)