Address passed in FireWire Register function calls

[inge at mandli.com]

Steve,

I've been trying to call IOXGetFireWireDeviceRegister and
IOXSetFireWireDeviceRegister. However, the address passed was only 32-bit.
According to IIDC-1394 specification, the base address is FFFF Fxxx xxxx.
According to Point Grey documentation, the base address of the Scorpion
camera is FFF F0F0 0000. While calling IOXGetFireWireDeviceRegisteri and
IOXSetFireWireDeviceRegister, how could I know what's the full or upper
part of the address of the register I'm accessing (i.e. the first 16-bit
of the address-FFFF)?

Thanks,
Inge