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ExpMgrIOReadWord

You can use the ExpMgrIOReadWord function to read the word value at a specific address in PCI I/O space.



 
OSErr ExpMgrIOReadWord (

                     RegEntryIDPtr node,

                     LogicalAddress ioAddr,

                     UInt16 *valuePtr);

node: A node identifier that identifies a device node. If you specify a node identifier that isn't in the device tree, ExpMgrIOReadWord returns a result code of deviceTreeInvalidNodeErr.
ioAddr: The sum of the assigned-addresses base address of the device plus the offset to the desired I/O address.
valuePtr: The returned 16-bit value as it would appear on the PCI bus. The function performs the necessary byte swapping.

DESCRIPTION

The ExpMgrIOReadWord function reads the word at the I/O address for device node node determined by address ioAddr, returning its byte-swapped value in valuePtr.

RESULT CODES

`noErr`	0	No error
`deviceTreeInvalidNodeErr`	-2538	Device node not in the device tree