Copy (COP) - Synchronous Copy (CPS)

This information applies to the

CompactLogix

5370,

ControlLogix

5570,

Compact GuardLogix

5370,

GuardLogix

5570,

CompactLogix

5380,

CompactLogix

5480, and

ControlLogix

5580 controllers. Controller differences are noted where applicable.

The COP and CPS instructions copy the value(s) in the Source to the values in the Dest. The Source remains unchanged.

Available Languages

Ladder Diagram

Function Block

This instruction is not available in function block.

Structured Text

COP(Source,Dest,Length);

CPS(Source,Dest,Length);

Operands

IMPORTANT:

Unexpected operation may occur if:

Output tag operands are overwritten.

Members of a structure operand are overwritten.

Except when specified, structure operands are shared by multiple instructions.

Ladder Diagram

Operand	CompactLogix 5370, ControlLogix 5570, Compact GuardLogix 5370, and GuardLogix 5570 controllers Data Type	CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers Data Type	Format	Description
Source	SINT INT DINT LINT REAL String type structure	SINT INT DINT LINT USINT UINT UDINT ULINT REAL LREAL String type structure	tag	Initial element to copy. For controllers that support the REF_TO motion data types, the supported axis operand type can be replaced by an equivalent REF_TO type. The Reference (REF) Instruction associates a reference with an axis or coordinate system concrete tag.
Dest	SINT INT DINT LINT REAL String type structure	SINT INT DINT LINT USINT UINT UDINT ULINT REAL LREAL String type structure	tag	Initial element to be overwritten by the Source
Length	SINT INT DINT	SINT INT DINT	immediate tag	Number of Destination elements to copy

Structured Text

Operand	CompactLogix 5370, ControlLogix 5570, Compact GuardLogix 5370, and GuardLogix 5570 controllers Data Type	CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers Data Type	Format	Description
Source	SINT INT DINT LINT REAL String type structure	SINT INT DINT LINT USINT UINT UDINT ULINT REAL LREAL String type structure REF_TO_AXIS_VIRTUAL REF_TO_AXIS_CONSUMED REF_TO_AXIS_GENERIC_DRIVE REF_TO_AXIS_SERVO REF_TO_AXIS_SERVO_DRIVE REF_TO_AXIS_CIP_DRIVE	tag	Initial element to copy
Dest	SINT INT DINT LINT REAL String type structure	SINT INT DINT LINT USINT UINT UDINT ULINT REAL LREAL String type structure	tag	Initial element to be overwritten by the Source
Length	SINT INT DINT	SINT INT DINT	immediate tag	Number of Destination elements to copy

See Structured Text Syntax
for more information on the syntax of expressions within structured text.

Affects Math Status Flags

Major/Minor Faults

None specific to this instruction. See Index Through Arrays
for array-indexing faults.

Execution

Ladder Diagram

Condition/State	Action Taken
Prescan	N/A
Rung-condition-in is false	Set Rung-condition-out to Rung-condition-in.
Rung-condition-in is true	Set Rung-condition-out to Rung-condition-in. The instruction copies the data.
Postscan	N/A

Structured Text

Condition/State	Action Taken
Prescan	See Prescan in the Ladder Diagram table
Normal execution	See Rung-condition-in is true in Ladder Diagram table.
Postscan	See Postscan in the Ladder Diagram table.

During execution of the COP and CPS instructions, other controller actions may try to interrupt the copy operation and change the source:

If the source or destination is:	And need to:	Then select:	Notes
produced tag consumed tag I/O data data that another task can overwrite non-atomic tag that is written to by a remote device	Prevent the source data from changing during the copy operation	CPS	Tasks that attempt to interrupt a CPS instruction are delayed until the instruction is done. To estimate the execution time of the CPS instruction, refer to the ControlLogix System User Manual, publication 1756-UM001. Use interlock application code to ensure a remote client is not updating the source while the CPS instruction is executing.
	Allow the source data to change during the copy operation	COP
None of the above	--------------->	COP

The COP and CPS instructions operate on contiguous memory and perform a straight byte-to-byte memory copy.

When the Source and Dest are different data types the number of bytes copied equals the smaller of:

Requested amount equals Length x (the number of bytes in a destination element)

The number of bytes in the destination tag

For

Compact GuardLogix

5380,

CompactLogix

5380,

CompactLogix

5480,

ControlLogix

5580, or

GuardLogix

5580 controller

s: the number of bytes in the source tag

TIP:

The end of the destination or source tag is defined as the last byte of the base tag. If the tag is a structure, the end of the tag is the last byte of the last element of the structure. This means the COP and CPS instruction could write past the end of a member array but will never write past the end of the base tag.

IMPORTANT:

Test and confirm that the instruction does not change data that it should not change.

Examples

Example 1

Copy an array.

When enabled, the COP instruction copies 40 bytes from array_4 to array_5.

array_4 is a DINT (4 bytes per element) and contains 10 elements (total size = 40 bytes)

array_5 is a DINT (4 bytes per element) and contains 10 elements (total size = 40 bytes).

The Length says 10 destination elements should be copied so 40 bytes are copied.

Ladder Diagram

Structured Text

COP(array_4[0],array_5[0],10);

Example 2

Copy a structure.

When enabled, the COP instruction copies the structure timer_1 into element 5 of array_timer.

timer_1 is a TIMER (total size = 12 bytes).

array_timer is a TIMER (12 bytes per element) and contains 10 elements (total size = 120 bytes).

The Length says 1 destination elements so 12 bytes are copied.

Ladder Diagram

Structured Text

COP(timer_1,array_timer[5],1);

Example 3

Copy array data while preventing the data from being changed until the copy is complete.

The project_data array (100 elements) stores a variety of values that change at different times in the application. To send a complete image of project_data at one instance in time to another controller, the CPS instruction copies project_data to produced_array. While the CPS instruction copies the data, no I/O updates or other tasks can change the data. The produced_array tag produces the data on a ControlNet network for consumption by other controllers.

project_data is a DINT (4 bytes per element) and contains 100 elements (total size = 400 bytes)

produced_array is a DINT (4 bytes per element) and contains 100 elements (total size = 400 bytes).

The Length says 100 destination elements so 400 bytes are copied.

Ladder Diagram

Structured Text

CPS(project_data[0],produced_array[0],100);

Example 4

Copy data to a produced tag while preventing the data from being sent until the copy is complete.

Local:0:I.Data stores the input data for the DeviceNet network that is connected to the 1756-DNB module in slot 0. To synchronize the inputs with the application, the CPS instruction copies the input data to input_buffer. While the CPS instruction copies the data, no I/O updates can change the data. As the application executes, it uses for its inputs the input data in input_buffer.

Local:O:I.Data is a DINT (4 bytes per element) and contains 2 elements (total size = 8 bytes)

input_buffer is a DINT (4 bytes per element) and contains 20 elements (total size = 80 bytes).

The Length says 20 destination elements should be copied (4 X 20 = 80 bytes). However the source can only provide 8 bytes so 8 bytes are copied.

Ladder Diagram

Structured Text

CPS(Local:0:I.Data[0], input_buffer[0], 20);

Example 5

Initialize an array structure, initialize the first element and the use COP to replicate it to the rest of the array.

This example initializes an array or timer structures. When enabled, the MOV instructions initialize the .PRE and .ACC values of the first array_timer element. When enabled, the COP instruction copies a contiguous block of bytes, starting at array_timer[0]. The length is nine timer structures.

array_timer is a TIMER (12 bytes per element) and contains 15 elements (total size = 180 bytes)

The Length says 10 destination elements so 120 bytes are copied.

Ladder Diagram

Structured Text

IF S:FS THEN

array_timer[0].pre := 500;

array_timer[0].acc := 0;

COP(array_timer[0],array_timer[1],10);

END_IF;

Example 6

Copy different sized arrays.

When enabled, the COP instruction copies bytes from SINT array_6 to DNT array_7.

array_6 is a SINT (1 byte per element) and contains 5 elements (total size = 5 bytes)

array_7 is a DINT (4 bytes per element) and contains 10 elements (total size = 40 bytes).

The Length says 20 destination elements should be copied (4 X 20 = 80 bytes). However the dest can only accept 40 bytes and the source can only provide 5 bytes so 5 bytes are copied.

Ladder Diagram

Structured Text

COP(array_4[0],array_5[0],10);

Array File-Misc Instructions

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