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USB driver enumeration failure at high levels

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MacGyverS2000

Programmer
Jun 27, 2004
12
US
Not quite a C# question, but figured this was the best place to ask...

On an embedded system project, we're in need of a lot of USB ports. The motherboard itself has two hubs. Hub level 1 has several ports (which we do not have direct access to), and the hubs connect here. Therefore, the ports on the hubs become level 2. We have custom designed a board that mirrors a similar architecture (due to the number of ports we need), and this board plugs into the level 2 ports. So, ports here are at level 3, and ports off of the custom board's hub are at level 4 (confused yet?).

Some peripherals we plug in have their own hubs and associated ports, pushing any items plugged into those ports to level 5. So here's where it gets sticky.

Any items plugged into level 1-4 ports are found by the driver (the hubs are all FTDI chips), but items plugged into the level 5 ports are not (and I can only assume any higher levels would also not be found).

Is this a limitation I'm missing in the USB standard, or could it be a limitation in the driver. It is causing a number of headaches and I would like to resolve it.
 
Some more info, just in case anyone has suggestions:

If the driver is installed while the peripheral is plugged in to a high-level port (say level 5), it will continue to operate appropriately. If the peripheral is unplugged and plugged back into a lower-level port (say level 4), it will no longer work when plugged into the high-level port(5). To work at level 5 again, the driver must be uninstalled and reinstalled while the peripheral is plugged into a level 5 port.
 
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