Open topic with navigation
Port IO Functions
Control Functions
The following functionsare available to access Port I/O control services:
- RtEnablePortIo enables the direct Port I/O access for the specified range of I/O
addresses.
- RtDisablePortIo
disables the direct Port I/O access for the specified range of I/O addresses.
- Port I/O Data
Transfer functions (described in the following section)
Data Transfer Functions
The following functions are available to access Port I/O data transfer
services:
- RtReadPortUchar,RtReadPortUshort,RtReadPortUlong directly reads a one-, two-, or four-byte datum from the specified
I/O port.
- RtWritePortUchar,RtWritePortUshort,RtWritePortUlong
directly writes a one-, two-, or four-byte datum to the specified I/O
port.
- RtReadPortBufferUchar,RtReadPortBufferUshort,RtReadPortBufferUlong
copies a series of one-, two-, or four-byte datum from the specified I/O
port to a buffer.
- RtWritePortBufferUchar,RtWritePortBufferUshort,RtWritePortBufferUlong
copies a one-, two-, or four-byte datum from the specified I/O port to
a buffer.
General Programming Considerations
The RTX interfaces are coded in assembly and use the
__stdcall convention, indicating that the subroutines handle the
stack cleanup. You should not use other calling conventions.
Example
See the Interrupt Management and Port I/O Calls Programming Example in the RTX Example Reference. It demonstrates the use of RTX interrupt management and port I/O calls.
