"Wireless" Cables

Got a hardware problem? ask for help

Re: "Wireless" Cables

Postby Stryker » November 20th, 2012, 2:27 pm

asheets wrote:Sorry. AP == wireless access point. USBIP reciever == software you install on your computer.

As an example, I once had a requirement for running several USB JTAG devices remotely (over the company network). The JTAGs were in a secure room that didn't have a network or serial wiring, but there was wireless internet nearby. So, I hook the JTAGs up to a wireless laptop (which would be the RasPi, in your case), load up the USBIP server software, and send the USB connection over the wireless network.

On the other end (the next building over), I had a desktop computer wired into the company network that I loaded the USBIP receiver software on. I do a network query and detect the JTAGs on the network, and configure them for local use. With just a little bit of latency, the JTAGs worked just like they were hooked up to directly to the desktop.

Potentially, your could configure USBIP to work over the Internet (WWW), though I really wouldn't try it with anything more than a printer or a webcam, due to the latency induced by such a long connection.

Hmm. If I had a second laptop or computer, could I use that instead of an rPi? Also, how much latency is 'just a little bit'... this would be used by midi controllers for live music performances. Latency, aside from unexpected hardware disconnects, is the greatest problem a DJ faces...
User avatar
Stryker
 
Posts: 92
Joined: January 31st, 2011, 6:41 pm
Location: North Carolina

Re: "Wireless" Cables

Postby asheets » November 20th, 2012, 3:14 pm

Stryker wrote:Hmm. If I had a second laptop or computer, could I use that instead of an rPi? Also, how much latency is 'just a little bit'... this would be used by midi controllers for live music performances. Latency, aside from unexpected hardware disconnects, is the greatest problem a DJ faces...


It might be easier to use a 2nd laptop or computer that fuss with the RasPi. Then again, I haven't worked with a RasPi yet, and I tend to have spare laptops around. I originally proposed the RasPi because it is small and cheap, and potentially would work well. For a USB midi controller, I'd probably appreciate having the extra horsepower a nice i5 or i7 laptop would provide.

That could be a show-stopper... The sourceforge project for USBIP is nice and all that, but I wouldn't trust it if it absolutely, positively, has-to-be-there. I'm not sure I would trust a commercial USB-over-IP product for your application -- hell, I barely trust wireless microphones when I do sound at my church. Disconnects would be a major concern of mine. Hard wired == best, IMHO.

Latency? You'd have to test to say how bad it would be. You are going from a 480Mbps protocol (USB) to a potentially sub-100Mbps protocol (802.11G wireless ethernet). Incidentally, hardwired USB extensions using a variety of physical media (CAT6, XLR, power line, etc) may or may not run into similar issues.
asheets
 
Posts: 255
Joined: February 17th, 2011, 4:30 pm

Re: "Wireless" Cables

Postby Stryker » November 20th, 2012, 3:27 pm

asheets wrote:It might be easier to use a 2nd laptop or computer that fuss with the RasPi. Then again, I haven't worked with a RasPi yet, and I tend to have spare laptops around. I originally proposed the RasPi because it is small and cheap, and potentially would work well. For a USB midi controller, I'd probably appreciate having the extra horsepower a nice i5 or i7 laptop would provide.

That could be a show-stopper... The sourceforge project for USBIP is nice and all that, but I wouldn't trust it if it absolutely, positively, has-to-be-there. I'm not sure I would trust a commercial USB-over-IP product for your application -- hell, I barely trust wireless microphones when I do sound at my church. Disconnects would be a major concern of mine. Hard wired == best, IMHO.

Latency? You'd have to test to say how bad it would be. You are going from a 480Mbps protocol (USB) to a potentially sub-100Mbps protocol (802.11G wireless ethernet). Incidentally, hardwired USB extensions using a variety of physical media (CAT6, XLR, power line, etc) may or may not run into similar issues.

Hah. The new computer I got is an i5, the now old laptop is a Core 2 Duo.

That aside, what you're saying makes sense. Unfortunately loose cable connections is a show stopper right now and I'm trying to come up with a solution me and a buddy can use for performances, and going semi-wireless seemed the best solution. Right now we're thinking of building a thin plywood box that would hold a power strip, laptop/microcontroller (my laptop opens past 180°, so it would fit quite well), and some female sockets/holes for the cables to go through. We were thinking of mounting the controllers to the top of the box (which would be more like a tabletop in size and shape) and then connecting the controllers to the computer/microcontroller inside the box, running off the internal power supply or battery pack. At that point, the music application laptop(s) would be within a few feet of the box so as to maintain strong signals, so I think that's about all the kinks we can work out ahead of time.

Does that sound like a good idea?
User avatar
Stryker
 
Posts: 92
Joined: January 31st, 2011, 6:41 pm
Location: North Carolina

Previous

Return to Help me! Hardware

Who is online

Users browsing this forum: Yahoo [Bot] and 5 guests