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ExpMgrIOWriteByte

You can use the ExpMgrIOWriteByte function to write a byte to an address in PCI I/O space.



 
OSErr ExpMgrIOWriteByte (

                     RegEntryIDPtr node,

                     LogicalAddress ioAddr,

                     UInt8 value);

node: A node identifier that identifies a device node. If you specify a node identifier that isn't in the device tree, ExpMgrIOWriteByte 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.
value: The 8-bit value.

DESCRIPTION

The ExpMgrIOWriteByte function writes the value of value to the I/O address for device node node determined by address ioAddr.

RESULT CODES

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