T&T: Splitting the Signal of a USB GPS

[Peter Bennett]

Wednesday, February 25, 2009, 8:50:09 PM, Michael wrote:

M> If you are brave (or foolhardy) and good with a soldering iron you can
M> make a Y cable.  Most usb cables have a white, green, red, and black 
M> wire.  The better ones will have a separate shield.  The white wire and
M> the green wire are signal the red is +5 volts and the black is ground.
M> Cut one cable and attach the whites together and the greens together.
M> Don't connect the reds but the black and/or shield can also be 
M> connected.  You should have the white and green wires from the gps going
M> to each computer, only one computer should be feeding +5 volts to the 
M> gps and the grounds can be hooked together though the black wires.

I don't believe this will work. USB is a complex master/slave
communications protocol, with the computer being a master, and
everything else being a slave.  Your suggested Y-cord will have two
masters trying to communicate with the same slave.  It is highly
unlikely that either computer will communicate successfully with the
GPS, and the arrangement may mess up other USB communications on both
computers.

-- 
Peter Bennett, VE7CEI    Vancouver, B.C., Canada
Ennos 31 "Honeycomb"
GPS and NMEA info: http://vancouver-webpages.com/peter 
Vancouver Power Squadron: http://vancouver.powersquadron.ca