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ExpMgrConfigReadLong

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



 
OSErr ExpMgrConfigReadLong (

                     RegEntryIDPtr node,

                     LogicalAddress configAddr,

                     UInt32 *valuePtr);

node: A node identifier that identifies a device node. If you specify a node identifier that isn't in the device tree, ExpMgrConfigReadLong returns a result code of deviceTreeInvalidNodeErr.
configAddr: The configuration address (a value between 0 and 255).
valuePtr: The returned 32-bit value as it would appear on the PCI bus. The function performs the necessary byte swapping.

DESCRIPTION

The ExpMgrConfigReadLong function reads the long word starting 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