4 ms·

Infinite USB Plug

37 points by Flemlord 17y ago

NateLawson 17y ago
I don't think this guy understands USB. It isn't a matter of not having passthrough connectors, it's a matter of one device per port is how it fundamentally works. Unless he is planning to put a small 2-port hub in each connector (one for the device, one for the downstream port), this kind of thing just won't work. I'm guessing this is an issue of an industrial designer thinking "those silly computer engineers, why didn't they think to add passthrough?" without understanding how USB works.
- axod 17y ago
  Surely a 2 port hub would work and would be simple enough? That's how I assumed it'd work. Obviously you'd run out of power after 3 or 4 maybe, but that'd be enough to be useful. You can get pretty tiny 4 port hubs now.
  - pmjordan 17y ago
    From the Wikipedia page on USB: Additional USB hubs may be included in the tiers, allowing branching into a tree structure with up to five tier levels. So by "infinite" they mean "five", unless the connectors can make use of a non-standard communications mechanism between each other which makes them appear as only one big hub. The other downside of daisy-chaining is that you have to unplug everything to remove a lower-level device.
    - jules 17y ago
      And more than 5 of these sticking out of your device could easily break.
    - mmphosis 17y ago
      Up to 127 devices, including the hub devices, may be connected to a single host controller.
fnid2 17y ago
The question is, will usb device manufacturers pay for the extra hardware at the end of the wire?
- chaosmachine 17y ago
  Most USB devices aren't hardwired to a cable (except mice/keyboards). You just need to buy a few cables with these ends on them. It would also be possible to create an extension cable with one of these ends, for devices that are hardwired.
- trafficlight 17y ago
  Even if only a few of them do, we still win.
spamizbad 17y ago
Well, power-wise it's limited to a 5 unit load (100mW each) for USB 2.0. USB 3.0 can go to 900mW (150mW per load). This means you probably couldn't daisy-chain charging USB devices. Not infinite but still a compelling design.
- bugmenot 17y ago
  It would be trivial to give the system its own power bus. Right now each piece has a male USB port and a female port. Just add a male power plug and a female power plug to each. The last one takes power from an external power supply. If needed to isolate the systems, make each piece a full fledged hub so everything isn't considered on the same circuit. Indeed the article mentions the creator already arranged for external power input, so he may already have thought of this or a comparable solution.
potatolicious 17y ago
This has always been the reason I liked Firewire more than USB...
deleted 17y ago
[deleted]
tezza 17y ago
Ok, I need to remove a device in the middle of the chain... Now what will I be disconnecting to make this happen? I hope it's not my external HDD 2 hours into a transfer with 30 minutes left to go.

37 points by Flemlord 17y ago

I don't think this guy understands USB. It isn't a matter of not having passthrough connectors, it's a matter of one device per port is how it fundamentally works. Unless he is planning to put a small 2-port hub in each connector (one for the device, one for the downstream port), this kind of thing just won't work. I'm guessing this is an issue of an industrial designer thinking "those silly computer engineers, why didn't they think to add passthrough?" without understanding how USB works.

axod 17y ago
Surely a 2 port hub would work and would be simple enough? That's how I assumed it'd work. Obviously you'd run out of power after 3 or 4 maybe, but that'd be enough to be useful. You can get pretty tiny 4 port hubs now.
- pmjordan 17y ago
  From the Wikipedia page on USB: Additional USB hubs may be included in the tiers, allowing branching into a tree structure with up to five tier levels. So by "infinite" they mean "five", unless the connectors can make use of a non-standard communications mechanism between each other which makes them appear as only one big hub. The other downside of daisy-chaining is that you have to unplug everything to remove a lower-level device.
  - jules 17y ago
    And more than 5 of these sticking out of your device could easily break.
  - mmphosis 17y ago
    Up to 127 devices, including the hub devices, may be connected to a single host controller.

fnid2 17y ago

The question is, will usb device manufacturers pay for the extra hardware at the end of the wire?

chaosmachine 17y ago
Most USB devices aren't hardwired to a cable (except mice/keyboards). You just need to buy a few cables with these ends on them. It would also be possible to create an extension cable with one of these ends, for devices that are hardwired.
trafficlight 17y ago
Even if only a few of them do, we still win.

spamizbad 17y ago

Well, power-wise it's limited to a 5 unit load (100mW each) for USB 2.0. USB 3.0 can go to 900mW (150mW per load). This means you probably couldn't daisy-chain charging USB devices. Not infinite but still a compelling design.

bugmenot 17y ago
It would be trivial to give the system its own power bus. Right now each piece has a male USB port and a female port. Just add a male power plug and a female power plug to each. The last one takes power from an external power supply. If needed to isolate the systems, make each piece a full fledged hub so everything isn't considered on the same circuit. Indeed the article mentions the creator already arranged for external power input, so he may already have thought of this or a comparable solution.

potatolicious 17y ago

This has always been the reason I liked Firewire more than USB...

deleted 17y ago

[deleted]

tezza 17y ago

Ok, I need to remove a device in the middle of the chain... Now what will I be disconnecting to make this happen? I hope it's not my external HDD 2 hours into a transfer with 30 minutes left to go.