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Daisy-chaining USBs

"I also want daisy-chaining put back in the [USB] spec." - Philo

Thank goodness you wrote this, because all this time I thought I was hallucinating when I remembered early discussion of the daisy-chaining aspects of USB. I was sure I had imagined it because I have never ever ever seen a USB device that also included a USB port for the next device. (I briefly thought my new Dell monitor was providing this, until I realized it just had a built-in hub and was not itself a USB device.)

Can anyone tell me what happened to this functionality?

Zahid
Monday, January 19, 2004

The hub is the daisychain.  You connect hubs together (thus reducing the number of connections to two for hubs in the middle (using the original 4 port hubs) which is obviously pointless. 

So you end up with 8 port hubs which are effectively daisychained internally but stick two power sucking devices on there and one will probably fail.

And as for USB printers jeeze...

Simon Lucy
Monday, January 19, 2004

I believe the apple USB keyboard is an example of this. It contains a single USB port, presumably for the mouse or any other type of USB device.

m
Monday, January 19, 2004

I've seen PC USB keyboards that can daisy-chain USB mice.

However, I suspect the keyboard is simply acting as a two port hub, one for the keyboard and one for the mouse.

Steve Jones (UK)
Monday, January 19, 2004

[nod] when you plug in a USB keyboard you'll see the computer recognize a hub first, then a keyboard.

Philo

Philo
Monday, January 19, 2004

Interesting, but still you get the desired effect.

m
Monday, January 19, 2004

And where are the USB hubs in the monitors? These things have an AC connection, for god's sake. They could provide any amount of power required. There should be (at least) 4 USB ports hanging off every monitor made, in my opinion. It's the perfect place for casual device usage.

Brad Wilson (dotnetguy.techieswithcats.com)
Monday, January 19, 2004

"It's the perfect place for casual device usage. "

The taiwanese, although forward thinking economically, are very conservative socially. Casual device usage is considered decadent and generally frowned upon.


Monday, January 19, 2004

My LG Flatron 19" CRT has got one. However with the market being price conscious there are reasons for manufacturers to shy away form adding another $10 or so to the price

Stephen Jones
Monday, January 19, 2004

Those printer/scanner 300-in-1 + steak knives combos have a hub built in too, but I haven't seen any with daisy chain capability.

From the PC point of view, it sees a 2 port hub, with a printer on one port, and a scanner on the other.  (The hub probably supports 4 ports, so plugging your keyboard into your printer could happen.)

Much swearing ensures when the scanner is recognised, but not the printer.  More swearing occurs when trying to explain the above configuration to people who don't care - 'If it scans, why won't it print?'

AJS
Monday, January 19, 2004

The sad part about daisy chaining USB devices is that you end up taking a performance hit with each additional USB device...

SC
Monday, January 19, 2004

Actually, there seems to be a cycle here.

First you started off adding everything externally. Then along came expansion cards and everybody was overjoyed they didn't have to clutter up their desktop anymore.

Then, after the IRQ problems had been successfully sorted out with the PCI bus, everybody suddenly went back to small form PC's and having their desktop all clogged up with peripherals again.

The thing that most irritates me is to see perfectly good peripherals become obsolete. I can tolerate buying a new scanner every time I upgrade the OS, because at  least the replacement is way better than the old one (though for the half-dozen faxes I send a year it hardly matters) but I suspect when I upgrade my present 1999 motherboard I'm going to have to retire a seraia port 3com modem, and worst of all the serial port Wacom tablet that I haven't even got round to doing the tutorial for yet!

Stephen Jones
Monday, January 19, 2004

Philo, you wouldn't happen to be doing any product development for a new Microsoft Desktop computer would you?

;-)

www.MarkTAW.com
Monday, January 19, 2004

No, but I'm thinking of making it a personal agenda to find out how BillG deals with his power bricks...

Philo

Philo
Monday, January 19, 2004

He has a very small wasted boy under his desk for such menial tasks.


He may even have  a very small waist as well.

Simon Lucy
Monday, January 19, 2004

re peripherals:

I could care less about brick proliferation. At least I can stuff them in a huge tangle under the desk! And daisy chained USB seems to work well with the hub concept.

What drives me INSANE is this perpheral bloat. Freaking desktop covered with the damn things. Wires everywhere.

And worse than that - consumer home entertainment systems. Shit. Looks like a damn electronics shop in my living room. Get a wireless stereo component and it doesn't have the same wireless protocol as the damn DVD so I hve to use wires anyway. And these horrid horrid speakers with their wires and ugly case designs. Either go without the home entertainment system or look like you live in a junkyard, or hire someone to tear out your walls for $20,000 and make everything built in - until next year when all the formats change and you have to rewire again.

This stuff is really a mess. A big mess. And its getting worse.

Tony Chang
Monday, January 19, 2004

Tony,

What kind of wireless audio components do you have?

apw
Monday, January 19, 2004

Hi Guys can you Daisy chain just keyboards... say 5 boards?

Gaz Jackson
Thursday, April 15, 2004

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