Windows equivalent of inb(), outb(), low level i/o

Question

I have some Linux code that monitors our hardware by collecting temperatures, voltages, and fan speeds, from the motherboard using inb(), outb(), inl(), etc. low level i/o functions.

My challenge is to port that code over to run under Windows as a simple console app. But am puzzled in what functions Win32 (or .NET) provide that allow me permission to access direct memory mapped ports.

I don't want to code a system driver either.

My Windows tool preference is VS2008. (fyi)

Is this possible?

Answer 1

The default protection level for I/O ports in Windows prevents a user-mode program from using inp and out instructions on any port. Your program will die with a GPF. There are several freely available drivers around that change that protection level so that ring 3 code can access the ports. Which is okay if you're interested in killer pokes.

The canonical one is inpout32.

Answer 2

Most hardware locations are mapped in areas not accesible from userspace, so you are going to need a device driver that provides the desired API.

You can also check the UNIX Application Migration Guide ad MSDN.

Answer 3

Well, after much searching with some trial and error, the two most useful bits I found to be helpful are:

WinRing0 and IO.DLL .

They pretty much do the same thing, the difference is the samples of code you will find to help you get started using them.

Hope this helps for others.