ReadPortB

Read bytes from a PC port

Declaration

Source position: x86.pp line 25

  function ReadPortB(Port: LongInt) : Byte;
  procedure ReadPortB(Port: LongInt; var Buf; Count: LongInt);

Description

The procedural form of ReadPortB reads Count bytes from port Port and stores them in Buf. There must be enough memory allocated at Buf to store Count bytes.

The functional form of ReadPortB reads 1 byte from port B and returns the byte that was read.

Note that you need permission to read a port. This permission can be set by the root user with the FpIOPerm call.

Errors

In case of an error (not enough permissions read this port), runtime 216 (Access Violation) will occur.

See also

Name Description
FpIOPerm Set permission on IO ports
ReadPort Read data from a PC port
ReadPortL Read longints from a PC port
ReadPortW Read Words from a PC port
WritePort Write data to PC port
WritePortB Write byte to PC port
WritePortL Write longint to PC port.
WritePortW Write Word to PC port