Build USB Long Cable

if you have low capacitance how ever, I would make a buffer driver system to beef up the current. They use to make these things call Black Boxes for RS-232 runs. they were nothing more than twisted balanced input and outputs which gives you lots length to work with.

actually, I think products already exist for that.

--
"I\'m never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5

USB is NOTHING like RS232 in its cabling requirements.

There are two conductors for data, power and ground. There are USB extenders on the market when you need a longer line. You run into timing errors with long cables, without using an extender. It is a bi-directional communications device that regenerates the USB signals.

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Service to my country? Been there, Done that, and I\'ve got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

Yes, I am aware of this, so isn't the RS-232 as 2 conductors RX and TX for data streams how ever, that doesn't change the facts that long haul units were made implementing twisted pair balanced lines to transport between to units and thus back into RS232 again. I know this because I have a whole load of these "Black Boxes" and they also work with USB, I'm using one to transport USB cable on a long haul from a machine to a PC to monitor settings in a machine... I simply made a conversion plug and used a couple of existing black boxes I have in my arsenal. These units claim a long distant but the 2 i'm currently using are running aprox 3000 Feet to get the signal into the shop. They have been working fine with no data problems that i know of.. on the scope the signal looks good.. Can't tell you the speed it's operating at because I don't know that..

P.S. we're using FEP cat 5 wire if that makes any difference, since we make that kind of wire there, it was just convenient at the time.

--
"I\'m never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5

You want a 'balanced RS232' ?

Use RS485.

Graham

Only two of the lines carry signals, the other two are power, however the spec says it won't work. But you can buy extender cables - try two of those and see if it works.

Go ahead and keep advising people to do things outside of the specs. You are obviously smarter than anyone else on Earth, including the people who develop the technology and write the standards. Let people waste their time tryting to make it work properly, what do you care?

--
Service to my country? Been there, Done that, and I\'ve got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

thanks all, but

I looking after cheap solution for long cable for long cable for my Point devices (USB Keyboard + USB mouse + Touchpad).

It's posible to achive this target with some trick?

5m than you'll need a hub, after that you can have another 5 metres (and then another hub if you want to go further).

--

Bye.
   Jasen

Circa Mon, 28 May 2007 01:19:32 GMT recorded as looks like "Homer J Simpson" sounds like:

This outfit:

is marketing a device that claims 150' range via cat5e cable interconnect.

Circa Sun, 27 May 2007 20:59:03 -0400 recorded as looks like Jamie sounds like:

It sounds like what you have is an RS232 to RS422/485 converter. Do you have a part number or some other identifying mark for these "black boxes?" I'm very interested in finding out how they buffer the input data.

Your shop is a half-mile from your home? That's a big property you have there. Here is the limitation of your setup: cable length vs. data rate. The data rate limit of RS422/485 varies with cable length. At 3000', you will have 20% jitter (that's a lot) at a data rate of 800kbps. (Nat'l Semiconductor Application Note 214, August 1993)

The USB 1.1 standard has two data rates, 1.5Mbps and 12Mbps. Apparently the slowest USB rate exceeds by double the capability of the RS422/485 standard at that cable length. Commercial USB->RS485 converters I've googled don't claim higher than 1Mbps (921.6kbps is a typical maximum). I'd also like to find out how these commercial devices handle the data rate difference. Anyone?

If you can see the signal on a scope, then you should be able to calculate the data rate. I'd be very interested in knowing what rate you are achieving.

At

I've used USB cable extenders, but except they had PS-2 mouse-type connectors. I got reliable USB over 12', which is close to 4 meters.

Good Luck! Rich

Yes :-) it can be done :-)

non-powered version: http://193.189.160.28/seibert/HP/UsbEnh/UsbLongCable2.gif

& this I use also for powering a wifi Usb stick at the same time http://193.189.160.28/seibert/HP/UsbEnh/UsbLongCable.gif

This last for example approx.15m long "fast DIY" made with ordinary TV coax I used it for my active wifi UsbKey antenna experiments : http://193.189.160.28/seibert/HP/UsbEnh/UsbProlAll.jpg http://193.189.160.28/seibert/HP/UsbEnh/UsbProlEnds.jpg

Ps.: if anybody would like to check (pics&data only of) that my 2,4GHz active WLAN UsbKey antenna DIY extending range experiments, you can do it here (text is in my native language-slovene & not in english, so you would not understand it probably, but you could get some clues) :

.. have fun ... :-)

-- Regards , SPAJKY ® mail addr. @ my site @

5y - "Tualatin OC-ed / BX-Slot1 / inaudible setup!"

Your a dumbass. Your the one who actually thinks they are the smartest person on Earth and you get pissed when someone doesn't do things your way or agree with your methods.