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include vmm.inc
 
Dispatch_Byte_IO In_Proc, Out_Proc
 
The Dispatch_Byte_IO macro checks the size of the I/O request and dispatches
the request to either the Simulate_IO service or to the specified
single-byte input or output procedure. I/O callback procedures use this
macro to simplify processing of I/O requests.
 
Parameter  Description
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In_Proc    Specifies the name of the procedure to carry out a single-byte
           input operation. If this parameter is the Fall_Through keyword,
           the macro ignores input operations.
 
Out_Proc   Specifies the name of the procedure to carry out a single-byte
           output operation. If this parameter is the Fall_Through keyword,
           the macro ignores output operations.
 
Return Value
 
This macro has no return value.
 
Comments
 
The EAX, EBX, ECX, EDX, and EBP registers must contain values specified as
valid input parameters for the Simulate_IO service. Dispatch_Byte_IO checks
the ECX register for the I/O type. If this type specifies an I/O request
that is larger than a byte, the macro jumps to the Simulate_IO service.
 
See Also
 
Emulate_Non_Byte_IO, Simulate_IO
 
 
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