Debugging USB Wireless

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Probe the internal dongle

For debugging, it may be useful to put a USB analyer on the internal wireless unit to take advantage of the EC wakeup and other signals on the board that are not available when using a dongle. Here are some rework instructions to accomplish this (many thanks to AMD's Mike Stember for the instructions):

  • Remove R464 and R465. This will disconnect the internal wireless dongle from its USB port.
  • Cut a standard USB cable in half so you are left with the A connector and the very shortest wires you can manage.
  • The green wire should be soldered to pin 6 of the wireless unit (D+)
  • The white wire should be soldered to pin 5 of the wireless unit (D-)
  • The black wire should be soldered to pin of C419 closest to the edge of the card. (GND) This point is selected as it is a large round point to accommodate the typically large ground wire.
  • Plug a standard USB cable into one of the standard USB ports and then into your protocol analyzer. Use a short (1 meter) cable to ensure good signal quality.
  • Plug the other end of the analyzer into the very short cable on the wireless unit (you may need to maneuver around to do that).

You can now use the system as usual. The only difference is that the wireless module will appear on a different USB port than normal but this doesn't make a difference to any of the software.

Pictures

Connecting the dongle to the analyzer
Connecting the short wire to the dongle
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