F_iecCopyStreamToBuffer

Syntax

FUNCTION F_iecCopyStreamToBuffer: UDINT
VAR_INPUT
    pBuffer : PVOID;
    cbBuffer: UDINT;
END_VAR
VAR_IN_OUT
    stream  : ST_IEC870_5_101Stream;
END_VAR

Inputs

pBuffer: Pointer (address) of an external buffer variable.

cbBuffer: Maximum number of data bytes to be copied from the stream variable to the external buffer.

Inputs/outputs

stream: Source data buffer.

Sample in ST

A rising edge at bRx results in copying of the first four data bytes of the stream variable to the rxBufferA and rxBufferB variables.

PROGRAM P_iecCopyStreamToBuffer
VAR
    stream    : ST_IEC870_5_101Stream := ( length := 4, data := [16#01, 16#02, 16#03, 16#04] );
    rxBufferA : ARRAY[0..3] OF BYTE;
    rxBufferB : ARRAY[0..3] OF BYTE;
    cbResult  : UDINT;
    bRx       : BOOL;
END_VAR

IF bRx THEN
    bRx := FALSE;
    cbResult := F_iecCopyStreamToBuffer ( ADR( rxBufferA ), SIZEOF( rxBufferA ), stream );
    cbResult := F_iecCopyStreamToBuffer ( ADR( rxBufferB ), SIZEOF( rxBufferB ), stream );
END_IF

Memory representation of the stream variable after the program start:

Memory representation of the stream variable after the first and second F_CopyStreamToBuffer function calls:

The rxBufferA and rxBufferB array variables have the following values after the call: [16#01, 16#02, 16#03, 16#04].

Requirements