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Port Address Translation or Port Access Redirection

Modern parallel port cards for either PCI, PCIexpress, and ExpressCard (via PCIe) have fixed port base addresses above 0x1000, e.g. 0x3008. You cannot set their address to one of the well-known ISA addresses 0x378 or 0x278. (Note the address 0x3BC is not capable for EPP and ECP.)

Some older software cannot use an arbitrary port address, and you run into serious trouble. For example, the well-known avrdude command-line chip programmer.