How do I access memory-mapped USB host controller registers?

Question

I'm trying to read memory-mapped registers of usb host controller. As I understand, the content of the registers should be placed into memory, starting from some address, which can be retrieved from PCI configuration registers of controller (USBBASE in particular).

I managed to get this address, and it seems to be valid. At least it is equal to one I can get via everest. The problem is that any attempt to read data from memory using this address results into "access violation" error. Stuff like memcpy just doesn't work. Maybe somebody knows the way to read host controller capability registers and host controller operational registers? Thanks in advance. PS. I'm working on windows 7.

Answer 1

Well, it seems that at least on x64 system it can't be achieved without using any special libraries. Things might be easier with x32 systems, but I didn't try it. Anyway, things like that is not for user space programs. PS. Wrote this just to close the thread.