Documentation

Open Port

Port opening

Function name

OPENPORT

Function

Function opens a port communication according to the entered data. The communication available is TCP, UDP, or serial line.

Inputs

Input Type Description
DEFINITION STRING_REF Access parameters of the communication.

Outputs

Output Type Description
=> IO.COMMHANDLE Parameters of a running communication

Example of a ST call:

PROGRAM main
(program's body)
var
def : string;
handle : io.commhandle;
state : int := 0;
data : array[0..31] of byte;
dataRecv : array[0..31] of byte;
received : int;
end_var
case state of
0:
(*def := 'tcp:192.168.1.4:7';*)
(*def := 'udp:192.168.1.4:7';*)
def := 'serial:10:9600,8,N,1';
handle := io.openport(def);
if handle >= 0 then
state := 1;
end_if;
1:
if io.getportstatus(handle) = 0 then (* OperationStatus_Ok *)
(* connection established *)
data[0] := 5;
data[1] := 10;
data[2] := 6;
data[3] := 11;
if io.writeport(handle, adr data[0], 10) then
state := 2;
end_if;
end_if;
2:
if io.getportstatus(handle) = 0 then (* OperationStatus_Ok *)
(* all data sent *)
state := 3;
end_if;
3:
received := io.readport(handle, adr dataRecv[0], 20);
if received > 0 then
(* some data received *)
io.closeport(handle);
state := 4;
else
io.getportstatus(handle);
end_if;
else
state := 4;
end_case;
END_PROGRAM