SerializeInPLCopen motion icon

Description

Extract the value of a variable from a binary frame. This function is commonly used for extracting data from a communication frame in binary format.

In LDClosed"Ladder diagram" Ladder logic is a method of drawing electrical logic schematics. It is now a very popular graphical language for programming Programmable Logic Controllers (PLCs). It was originally invented to describe logic made from relays. The name is based on the observation that programs in this language resemble ladders, with two vertical "rails" and a series of horizontal "rungs" between them language, the operation is executed only if the input rung (EN) is TRUE. The output rung (ENO) keeps the same value as the input rung.

The FRAME input must fit the input position and data size. If the value cannot be safely extracted, the function returns 0. The DATA input must be directly connected to a variable, and cannot be a constant or complex expression. This variable will be forced with the extracted value.

The function extracts the following number of bytes from the source frame:

1 byte BOOL, SINT, USINT and BYTE variables
2 bytes INT, UINT and WORD variables
4 bytes DINT, UDINT, DWORD and REAL variables
8 bytes LINT and LREAL variables

  • The function cannot be used to serialize STRING variables.

The function returns the position in the source frame, after the extracted data. Thus the return value can be used as a position for the next serialization

Arguments

Input

En Description Execute the function
  Data type BOOL
  Range [0,1]
  Unit n/a
  Default
FrameClosedIn networking dialect, a message is called a frame[] Description Source buffer - must be an array.
  Data type USINT
  Range [0,+65535]
  Unit n/a
  Default n/a
Data Description Destination variable to be copied
  Data type any except STRING
  Range
  Unit n/a
  Default
Pos Description Position in the source buffer
  Data type DINT
  Range [0,+65535]
  Unit n/a
  Default n/a
BigEndian Description TRUE if the frame is encoded with Big Endian format.
  Data type BOOL
  Range ?
  Unit ?
  Default ?

Output

OK Description Returns true when the function successfully executes. See Function - General rules.
  Data type BOOL
  Unit n/a
NextPos Description Position in the source buffer after the extracted data. 0 in case or error (invalid position / buffer size).
  Data type DINT
  Unit n/a

Examples

Structured Text

NextPos := SerializeIn(Frame[](*USINT*), @Data(*ANY*), Pos(*DINT*), BigEndian(*BOOL*)); //Read the position