canitpSessionSend (Function)

Send an ISO-TP message.

The destination of the message is set in the canitpSessionCreate function, using the dst parameter.

Input:

handle : SYSHANDLE

The handle of the ISO-TP session to send the data on.

data : PTR

The buffer with the message to send.

size : INT (1..4095)

The size of the message in bytes.

Returns: INT

Declaration:

FUNCTION canitpSessionSend : INT;
VAR_INPUT
  handle : SYSHANDLE;
  data   : PTR;
  size   : INT;
END_VAR;

Example:

INCLUDE rtcu.inc
VAR
  buf   : ARRAY [1..4096] OF SINT;
END_VAR;
 
FUNCTION CALLBACK canitpRecv
VAR_INPUT
  handle : SYSHANDLE; //Handle to session
  arg    : DINT; //User data
  size   : INT; //Size of the data received.
END_VAR;
  DebugMsg(message := strFromMemory(src := PTR(arg), len := size));
END_FUNCTION;
 
 
PROGRAM example;
VAR
  handle: SYSHANDLE;
  rc    : INT;
  str   : STRING;
  out   : ARRAY [1..4095] OF SINT;
  len   : INT;
END_VAR;
 
  // Open can
  canOpen(baud := 250, monitor := FALSE);
 
  // Create ISO-TP session
  rc := canitpSessionCreate(handle:=handle,
                  port     := 1,
                  src      := 16#12345678,
                  dst      := 16#12345679,
                  cb_receive := @canitpRecv,
                  cb_data    := ADDR(buf),
                  cb_arg     := DINT(ADDR(buf)),
                  cb_size    := SIZEOF(buf));
  IF rc < 1 THEN
    DebugFmt(message := "canitpSessionCreate=\1", v1 := rc);
    RETURN;
  END_IF;
 
  // Build message
  str := "Hello from RTCU device";
 
  // Send message
  len := strLen(str := str);
  strToMemory(str := str, dst := ADDR(out), len := len);
  rc  := canitpSessionSend(handle:=handle, data := ADDR(out), size := len);
  IF rc < 1 THEN
    DebugFmt(message := "canitpSessionSend=\1", v1 := rc);
    RETURN;
  END_IF;
 
BEGIN
 
END;
END_PROGRAM;