MEMCPY block

Short summary

Name

MEMCPY

→POU type

→function

Category

IEC-block, MemoryEnh, block with internal error diagnostic

Conform to →IEC-standard

images/s/b2ic8e/9012/1ca6q62/_/images/icons/emoticons/add.svg not defined in IEC-standard

Graphical interface

images/download/thumbnails/414781835/MEMCPY-version-1-modificationdate-1535027027963-api-v2.png

Available since

  • version 1.35.0 (for logi.CAD 3) – initial variant

  • version 2.0.9 (for library Standard) – graphical interface with in-out variables

Functionality

The block copies the memory of one connected input value to another connected input value.

You enter the first input value at input SRC and the second input value at input DEST. At input LEN, enter the numer of bytes to be copied.
By default, value 0 is specified for the number of bytes.

Special cases:

  • In case of LEN = 0, the block automatically calculates the number of bytes to copy for SRC and DEST.

  • If the value for LEN is > than the maximally possible size of the input values DEST and SRC, the block copies until the maximally possible size of the input value. In this case, the output ENO is set to value FALSE.

  • If a STRING element with a length is connected to SRC or DEST, the length of the STRING buffer is used. The length of the STRING buffer is determined by the declaration.
    STRING elements with a length are STRING variables declared by you; see " Declaration of STRING variables (incl. access)".

  • If a STRING element without a length is connected to SRC or DEST , the length of the STRING buffer is also used. However, the length of the STRING buffer is determined by the resulting value.
    STRING elements without a user-defined length are resulting, if you are using STRING functions or →character string literal.

Inputs, outputs

Identifier

→Data type

Description

In-outs
(VAR_IN_OUT):

DEST

REAL, LREAL, USINT, UINT, UDINT, ULINT, SINT, INT, DINT, LINT, TIME, BOOL, BYTE, WORD, DWORD, LWORD, STRING, CHAR, DATE_AND_TIME, DATE, TIME_OF_DAY or a →user-defined data type
Restriction: In case of →array data types, only one-dimensional arrays are allowed.

destination

SRC

REAL, LREAL, USINT, UINT, UDINT, ULINT, SINT, INT, DINT, LINT, TIME, BOOL, BYTE, WORD, DWORD, LWORD, STRING, CHAR, DATE_AND_TIME, DATE, TIME_OF_DAY or a →user-defined data type
Restriction: In case of →array data types, only one-dimensional arrays are allowed.

source

Inputs:

LEN

UDINT

the number of bytes to be copied

Input EN and output ENO are available when →calling the block. See "Execution control: EN, ENO" for information on input EN and output ENO.

See:

Internal error diagnostic for block

The block checks the value connected to the inpu ts before it is executed.
If the value for LEN is > than the maximally possible size of the input values SRC and DEST , the output ENO of the block is set to value FALSE (or an equivalent).

Example for usage within ST-editor

PROGRAM Test
VAR
Var1 : BYTE := 0;
Var2 : BYTE := 10;
Var3 : DINT := 0;
Var4 : DINT := 100;
Var5 : DINT := 0;
Var6 : DINT := 40000;
END_VAR
MEMCPY(DEST := Var1, SRC := Var2, LEN := 1); (* The variable 'Var1' evaluates to '10'. *)
MEMCPY(DEST := Var3, SRC := Var4, LEN := 1); (* The variable 'Var3' evaluates to '100'. *)
MEMCPY(DEST := Var5, SRC := Var6, LEN := 1); (* The variable 'Var3' evaluates to '64'. *)
END_PROGRAM

When creating your application within the ST-editor, enter a call of a block by typing the text as requested by the syntax or use Content Assist.