Electronics Maximum USB extension?

Hey all,

I'm getting a TV for my room soon, and I still have an old nintendo SNES and N64, but my little brother still plays on them. So I've been using an emulator (only on games I own, even though nintendo still regards these images as illegal). However, playing in a cheap desk chair on a 15" monitor is not the most relaxing experience. I plan on hooking up my telly to my PC and using my adaptoid (N64 controller -> USB converter) for a control device. In any case I need a h00ge extension cable to make the distance. From where I'll be setting to the TV is at least 2.5m, and then I'll need about another 3m to get to my PC. I can get 5m extension cables for €8,- but I'm poor and could just hack up my 1m extension cable and add some length to it. But I'm worried about interference.

So how long can I make a USB cable before it starts to get unstable? I don't think it matters wether it can handle USB2.0 but it needs to work in the first place

 

pretty sure its 7meters...

 

the USB2 standards say 5 meter extension is max and that you can use a maximum of 5 repeaters, giving you 30 meters of extension (5 x 5 + 5 meters from the last repeater to the computer)

Repeaters are pretty expensive thou.

IIRC, the USB1.1 standard says 3 meters.

You could probably go a bit longer if you use a well shielded wire with a little thicker wires than the original.

I am not sure if the data wires should be twisted, but probably.

 

Bah! i have a couple of unpowered USB extension cables (16 ft each) and have run USB 2.0 over two strung in sucession without any problems (32 ft)

Also, i have heard of people runing USB 1.1 over 80 ft of unshielded cat5 cable without problems. *the guy was sticking a USB nic on his roof, with a cantenna.*

 

Cool Now I have to find a cheap wire source, no point in buying 10 euros worth of 4-conductor wire so I don't have to spend 8 euros on an extension cable

 

Buy an 'active usb cable', we use them at work, very useful.

 

yeh these adaptors will be HID class probably USB slow, 1.5mbits.

just get some cat 5, and put ground in all the un-used wires, u'll be fine.

 

buying shelded 4 conductor wire is probably worth you while, if you want full usb 2.0.

 

Hmm there's a PC-discount convention on may 29th. I can prolly get my folks to pay the entrance fee, and there's this german dude who always sells PC cables cheep. A buddy got a really huge 5m headphone extension cable for a euro, mebbe he has something good to offer.

BTW, what exactly is 'active' USB?

 

it means that there is some sort of powered buffer and a higher level signal running along the length of the cable, so USB -> RS485 (for example) -> USB again. this allows much longer cable runs (this case, 1200m) , but at the expense of the speed of the intermittent protocol (theoretically 10mb/s). usually active cables require power at both ends, or at least at one end if a power lead runs the length of the cable

 

1200m? think of the size monitor you'd need to play games from that distance!!