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 |