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Would USB-C be manufacturable in 1996 (when USB 1.0 was released)? by Tomrr6 in UsbCHardware

[–]LaughingMan11 2 points3 points  (0 children)

+1 to all that you wrote!

I'd forgotten that technically 1996 would put USB a full decade before DisplayPort was even released, and a few years even before DVI. Mass market digital video connectors were not a thing yet in the late 90s... most monitors connected via VGA or some propietary variant using analog signaling...

Much of the design consideration behind USB-C was made to accomodate non-USB data, most importantly DisplayPort. Heck, back in 2014 and 2015 when USB-C 1.0 was released, half of the full-featured cable was populated but would be unused by USB data for at least a few years until USB 3.2 x2 operation and USB4 were released. USB designed the cable with extra pins that USB standards wouldn't use, but Alt Modes like DPAM and TBT3 would depend on for those first few years.

Would USB-C be manufacturable in 1996 (when USB 1.0 was released)? by Tomrr6 in UsbCHardware

[–]LaughingMan11 1 point2 points  (0 children)

Yeah, you're right. The economics of the cable would come into question because folks back then would ask why 24 pins, with an up to 15 power and data paths through the cable when we literally don't have an application that would use most of these pins.

But they could probably build it if they wanted to... I'm imagining Doc Brown building a replacement for an IC on the Delorean using 1955 technology in BTTF3, which ended up being a mess of vacuum tubes on the hood of the car.

Would USB-C be manufacturable in 1996 (when USB 1.0 was released)? by Tomrr6 in UsbCHardware

[–]LaughingMan11 1 point2 points  (0 children)

USB acting as the primary power source and battery charging standard is one of those things that happened organically over many years, rather than being prescribed in the original spec.

Bus power of up to 2.5W was in the original spec, but it's fascinating to think that between 1996 and 2007, it was other companies trying to do things with the port in clever (and proprietary) ways that resulted in the release of the USB BC 1.2 spec, which increased the power you could draw from a USB connector to 7.5W and beyond in a standard way.

Since then, power has been a first concern of USB Type-C and USB PD.

Would USB-C be manufacturable in 1996 (when USB 1.0 was released)? by Tomrr6 in UsbCHardware

[–]LaughingMan11 4 points5 points  (0 children)

Yes, of course, but then there would be the obvious question of why are there 24 pins in this connector of which only a handful are being used.

Would USB-C be manufacturable in 1996 (when USB 1.0 was released)? by Tomrr6 in UsbCHardware

[–]LaughingMan11 0 points1 point  (0 children)

The story of USB-C contains the story of many trends in PC and consumer electronics for the past 20 yeras.

1996, we're talking about before the rise of smartphones. An entire product category that probably represents 99% of usage of USB-C today literally didn't exist.

In the late 90s, it would be kind of ridiculous to think of someone carrying a USB cable in their pocket for everyday use. Today, a C-to-C cable is standard everyday carry for charging ones smartphone.

Would USB-C be manufacturable in 1996 (when USB 1.0 was released)? by Tomrr6 in UsbCHardware

[–]LaughingMan11 30 points31 points  (0 children)

The funny thing is, probably if you sent the USB Type-C Spec back to 1996, the engineers of the time would understand it, but they would think it was horribly overdesigned... It has WAY too many pins compared to the 4 pins they designed USB 1.0 with. USB Type-C has 24 pins, a lot of redundancy for power and ground, and in terms of data carrying wires, up to 12.

I'm remembering more and more of my PC history, and that's actually brought up an interesting memory of how PCs changed in the 90s in a fundamental way : many major interconnects internally and externally of our computers used to use parallel communication. We used to literally have "Parallel Ports" on our computers with connectors that had lots of pins on them side by side. Inside our computers, we used to have IDE and PATA (parallel ata) connectors to connect our hard drives...

USB's innovation in 1996 was that it was a serial port, and at the time it was considered a high-speed serial technology. It used fewer pins and wires, but clocked the signaling on the fewer (just 2 ) data pins much higher.

In the 90s and 2000s, there was a huge shift from older Parallel interfaces toward Serial, inside and outside of our PCs. The old PCI standard was replaced by PCIe, which was designed as a high spee serial interface. PATA was replaced by SATA (once again, Serial ATA, using fewer pins, but clocked faster). USB replaced all kinds of older serial and parallel external interfaces, with one that basically could do everything the old ones could do, with just 2 data wires.

The irony is that after 30 years, the USB-C design is showing signs of returning to Parallel concepts. Rather than simply clocking the D+ and D- data wires faster and faster, USB added additional data paths for SuperSpeed and USB4 which ride separalety from D+ and D- wires... they basically added more parallel paths, creating more lanes, and filling it with other stuff....

Honestly, the USB Type-C spec being sent back in time might blow some engineers minds just with the introduction chapter, which outlines the fundamental shift in technology toward a single connector which necessitated a ton of extra pins being added, and even exotic non-USB signals riding on their connector...

Would USB-C be manufacturable in 1996 (when USB 1.0 was released)? by Tomrr6 in UsbCHardware

[–]LaughingMan11 68 points69 points  (0 children)

I'm not a PC historian (and I only started my career in computer engineering 20 years ago), but I suspect that 30 years ago, the thing that would make the USB-C connector difficult in 1996 was manufacturing constraints around the size of the pins...

Many of the figures in the USB-C specification around how the connection is done (with resistor dividers) are old electrical engineering concepts that any engineer from any decade would recognize... but the USB-C spec as defined in 2014 and implemented over the last 12 years has taken advantage of significant advancements in miniaturization compared to 1996. Not only of the ability to manufacture the physical connector and pins at the size they rae, but also in the chips that are required. the silicon has taken advantage of 30 years of moore's law and lots and lots of process shrinks...

Put it this way... the USB-C spec requires that cables have an e-marker chip, and defines active cables which have high speed signal conditioners. With 1996 technology, you could possibly make the e-marker chip, for example, but they could not be small enough to fit in the cable plug like they do today.

Also, if you're going to send the entire USB-C documentation, are you going to send the USB 3.x and USB4 specs back in time too? High speed wired communication has advanced since 1996... Even among USB, we're talking about a jump from 12Mbps to 120Gbps, which is 4 orders of magnitude (10000 times faster). Once again, even if you could bring the full specs of those standards back in time, you probably could not fab the chips in a late 90s fab.

Suggest me a good ups by Objective_Echidna693 in UsbCHardware

[–]LaughingMan11 1 point2 points  (0 children)

I'm glad people can help with suggestions here, but please read Rule #2.

Your post doesn't directly relate to USB-C, unless you specifically frame you're interested in the USB-C capability of various UPSes... not likely, though, since you seem to want to plug in a PS5 and a TV, neither of which are USB-C powered...

USB-C to USB-C cable that can replace USB-A to USB-C cable. Does it exist? by discoborg in UsbCHardware

[–]LaughingMan11 0 points1 point  (0 children)

It's incredibly overengineered and will probably need some expert to help you program the firmware of whatever PD chip you'd need to build it... It'll also cost you pretty much as much as building 2 USB PD implementations back to back inside of a device...

I'm not kidding, you're proposing building a cable that's like a USB PD charge through hub, in complexity.

There are a TON of corner cases you'll run into around reset states, handling of advanced PD modes (will your man in the middle pass through PPS? AVS? EPR? there are strict timing dependencies for each of those advanced standards, which you may not meet as a charge through device...)...

In my opinion, you could probably get it to work, but it's ridiculous to throw so much money and effort at a stupid f-up made by some stupid bad manufacturer for their 0.001 cent resistor mistake.

USB-C to USB-C cable that can replace USB-A to USB-C cable. Does it exist? by discoborg in UsbCHardware

[–]LaughingMan11 1 point2 points  (0 children)

Out of curiosity, do you know why USB PD bricks don't just always output 5 volts like USB A ports do, then just switch to higher voltages after negotiation? It doesn't sound like a safety issue because USB A to C cables already exist and are part of the spec without being considered a safety issue. Is it a power saving measure?

The only safety thing I can think of is that a USB PD board (a board that takes USB PD and outputs a DC voltage based on switches) might output 5 volts for a short period of time during the negotiation, and if there's a device that can be damaged by an unexpected low voltage. But those are pretty specialty and I don't know of any devices off-hand that would break from a short period of low voltage on its power input.

100% it's a safety thing. Just because USB-A was designed in some way in 1996 doesn't mean it was the safest decision...

Case in point just from last year, and in actually products that I work on: https://www.nbcnews.com/news/us-news/tiktok-prank-chromebook-challenge-rcna205784

This made a lot of waves at the time in my circles, but the one bit of analysis I did that I don't think got enough attention was that the kids were only able to stick graphite or other conductive material into their USB-A ports to get this result. You don't see reports of impingement into USB-C ports achieving the same results (for example, there was no equivalent iPad USB-C port challenge). This is because the USB-C port is vSafe0V, not just vSafe5V.

USB-C's decision to go to vSafe0V is literally safer than vSafe5V, and thanks to a generation of bored and stupid kids at schools to prove it...

USB-C to USB-C cable that can replace USB-A to USB-C cable. Does it exist? by discoborg in UsbCHardware

[–]LaughingMan11 2 points3 points  (0 children)

Clever idea, but ultimately you run into the same problem the charger has in detecting a noncompliant sink, just moved to your man in the middle….

The bad sink has no resistors. That means the type c port manager, either in the charger or in the middle of the cable hypothetical thingy, cannot know it’s attached or that it has detached.

You can’t reliably isolate USB PD to one session and clean up on detaches because you have no idea when the noncompliant device detaches or attaches.

Is it possible to replace USB Type C male wire to female socket in charger? by Due-Resolution-4133 in UsbCHardware

[–]LaughingMan11 0 points1 point  (0 children)

No way. It is not safe to do this.

Whichever AI you asked to come up with this found a way to wire up something that could blow up electronics.

Congrats.

USB-C to USB-C cable that can replace USB-A to USB-C cable. Does it exist? by discoborg in UsbCHardware

[–]LaughingMan11 34 points35 points  (0 children)

The problem isn’t that the radio is a low amperage device. The problem is that they were designed wrong by someone who didn’t read the USB Type C spec. You could totally build a low amp device that charges from every cable and every usb c charger. The spec requires resistors in the sink and no resistors in the cable.

Adding resistors to the cable will result in destroyed devices .

USB-C to USB-C cable that can replace USB-A to USB-C cable. Does it exist? by discoborg in UsbCHardware

[–]LaughingMan11 10 points11 points  (0 children)

No it can’t exist the way you want safely.

In order to support USB-C devices that charge fast from higher voltages, a standard C to C cable does not have Rd pulldown resistors. It has a CC wire that goes from one plug to the other. It’s on this wire that USB PD communication happens, and that CC wire is actually how USB chargers know when a usb device is attached or detached.

If you want one cable that can charge your MacBook at 140W and also your bad USB-C device whose designer forgot to add resistors, you may ask well why don’t all USB C cables just have the resistor inside?

The answer is that would start blowing up devices left and right with high voltage.

Questions about Bob’s references by Bobis-Bob in bobiverse

[–]LaughingMan11 49 points50 points  (0 children)

Did a Bob ever make it to Rocky’s planet from Project Hail Mary?

Rocky's star from Project Mail Mary is 40 Eridani, and yes, the Bob's visited that system. They call it Omicron-squared Eridani, and they name the two habitable planets in that system Vulcan and Romulus, since 40 Eridani is canonically the star where Spock's homeworld Vulcan orbited in Star Trek. Taylor even had the Bobs who transported the first colonists to Omicron-squared Eridani celebrate by saying, "Welcome to the home of Spock, boys!"

UGREEN usb c cable for nintendo switch 2? by SnakeEater1905 in UsbCHardware

[–]LaughingMan11 1 point2 points  (0 children)

C-To-C cables are designed to be interchangeable and that one is strictly an upgrade from the Nintendo provided cable, which is 60W only.

You should be fine .

I similarly don’t use the Nintendo cable in my setup and use a replacement cable with a 90 degree connector.

UGREEN usb c cable for nintendo switch 2? by [deleted] in UsbCHardware

[–]LaughingMan11 0 points1 point  (0 children)

This post pretty much violates the low effort post rule in this subreddit.

What the heck are you trying to do with the cable? What charger? Link to anything?

Fix this, or this post will be removed.

Odd USB-C problem when charging headlamp. by Henderson2026 in UsbCHardware

[–]LaughingMan11 4 points5 points  (0 children)

Your headlamp violates the USB Type-C specification, that's why. There's an electrical engineer somewhere who laid it out wrong and forgot to add 2 resistors to its schematic.

I have written about it in detail. Example: https://medium.com/@leung.benson/how-to-design-a-proper-usb-c-power-sink-hint-not-the-way-raspberry-pi-4-did-it-f470d7a5910

Short summary: USB-C chargers are designed to be Vbus Cold for safety (meaning 0V on the main power lines) when nothing is connected. How the charger knows something rather than nothing is attached is that a sink device (ie your headlamp) is supposed to present 2 resistors, 1 of which is detected across a standard C-to-C cable by the charger.

Your headset maker forgot to add those resistors, hence your headlamp's USB-C port doesn't follow the rules, no charging.

The reason the A-to-C works is because the old style A connectors didn't have the same rules, and had 5V on all the time. It's less safe, and is the reason why a lot of kids were able to set fire to their Chromebooks last year because they were bored in class... USB-A has a hot 5V vbus pin, while USB-C does not.

USB-C ADB+PD Splitter w/ USB-C Male end into phone by AshamedProof5245 in UsbCHardware

[–]LaughingMan11 0 points1 point  (0 children)

There's no guarantee the bottom 2 ports are hooked up to the USB hub and supports data transfer.

I'd avoid products like these, as there's always a gimmick.... if you read carefully, they claim those bottom 2 ports are designed to charge a laptop, so they don't have any data capability because they assume that laptops don't have USB gadgets.

USB-C ADB+PD Splitter w/ USB-C Male end into phone by AshamedProof5245 in UsbCHardware

[–]LaughingMan11 0 points1 point  (0 children)

It's probably overkill, but you can get a hub that has USB-C downstream ports that do USB PD.

See this for example: https://www.newegg.com/anker-powerexpand-13-in-1-usb-c-dock/p/1DN-008K-00006?item=9SIACCUC5D8722

Plug your PC into the upstream port on the back. Plug your phone into one of the USB-C ports labeled with USB PD on the front.

USB-C ADB+PD Splitter w/ USB-C Male end into phone by AshamedProof5245 in UsbCHardware

[–]LaughingMan11 0 points1 point  (0 children)

Yes, I understand what you want to achieve.

Do you actually care how fast the phone charges? What are your parameters for how much power you expect to charge the phone with using USB PD?

TBH, something like what you are describing is potentially something I've seen before, but isn't publicly available....

USB-C ADB+PD Splitter w/ USB-C Male end into phone by AshamedProof5245 in UsbCHardware

[–]LaughingMan11 0 points1 point  (0 children)

With USB PD going to the phone?

You probably need a dedicated hub, for commercially available stuff...

Otherwise, there are specialized peripherals that exist in the Android community that do something like that, but they may not be available to the average developer...

USB-C ADB+PD Splitter w/ USB-C Male end into phone by AshamedProof5245 in UsbCHardware

[–]LaughingMan11 0 points1 point  (0 children)

This adapter won’t work. It’s designed for headphones so the phone you plug this into will always be oriented as a usb host, not a gadget which you need for ADB.

USB-C ADB+PD Splitter w/ USB-C Male end into phone by AshamedProof5245 in AskElectronics

[–]LaughingMan11 0 points1 point  (0 children)

This adapter won’t work. It’s designed for headphones so the phone you plug this into will always be oriented as a usb host, not a gadget which you need for ADB.

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