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ExpMgrConfigReadWord

You can use the ExpMgrConfigReadWord function to read the word value at a specific address in PCI configuration space.



 
OSErr ExpMgrConfigReadWord (

                     RegEntryIDPtr node,

                     LogicalAddress configAddr,

                     UInt16 *valuePtr);

node: A node identifier that identifies a device node. If you specify a node identifier that isn't in the device tree, ExpMgrConfigReadWord returns a result code of deviceTreeInvalidNodeErr.
configAddr: The configuration address (a value between 0 and 255).
valuePtr: The returned 16-bit value as it would appear on the PCI bus. The function performs the necessary byte swapping.

DESCRIPTION

The ExpMgrConfigReadWord function reads the word at the address in PCI configuration space for device node node determined by offset configAddr, returning its byte-swapped value in valuePtr.

RESULT CODES

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