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ExpMgrConfigReadByte

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



 
OSErr ExpMgrConfigReadByte (

                     RegEntryIDPtr node,

                     LogicalAddress configAddr,

                     UInt8 *valuePtr);

node: A node identifier that identifies a device node. If you specify a node identifier that isn't in the device tree, ExpMgrConfigReadByte returns a result code of deviceTreeInvalidNodeErr.
configAddr: The configuration address (a value between 0 and 255).
valuePtr: The returned 8-bit value.

DESCRIPTION

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

RESULT CODES

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