Multiply (MUL)

This information applies to the CompactLogix 5370, ControlLogix 5570, Compact GuardLogix 5370, GuardLogix 5570, Compact GuardLogix 5380, CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, and GuardLogix 5580 controllers. Controller differences are noted where applicable.
When enabled, the MUL instruction and the operator '*' multiplies Source A with Source B.
Available Languages
Ladder Diagram
L5K_MUL_LD_avail_v31
Function Block Diagram
Function Block Diagram supports these elements:
FBD Block
MUL_FBD_avail_v31
FBD Function
TIP:
FBD Function is applicable to CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers only.
MUL_avail lang
Structured Text
This instruction is not available in structured text.
TIP:
Use the operator '*' in an expression to compute the same result. Refer to
Structured Text Syntax
for more information on the syntax of expressions and assignments within structured text.
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.
There are data conversion rules for mixing numeric data types within an instruction. See Data Conversions.
Ladder Diagram
Operand
Data Type
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
Format
Description
Source A
SINT
INT
DINT
REAL
SINT
INT
DINT
LINT
USINT
UINT
UDINT
ULINT
REAL
LREAL
immediate
tag
Value of the multiplicand.
Source B
SINT
INT
DINT
REAL
SINT
INT
DINT
LINT
USINT
UINT
UDINT
ULINT
REAL
LREAL
immediate
tag
Value of the multiplier.
Dest
SINT
INT
DINT
REAL
SINT
INT
DINT
LINT
USINT
UINT
UDINT
ULINT
REAL
LREAL
tag
Tag to store the result of the instruction.
Function Block Diagram
FBD Block
Operand
Data Type
Format
Description
MUL
FBD_MATH
tag
MUL structure
FBD_MATH Structure
Input Members
Data Type
Description
EnableIn
BOOL
Enable input. If false, the instruction does not execute and outputs are not updated.
Default is true.
SourceA
REAL
Value of the multiplicand.
SourceB
REAL
Value of the multiplier.
Output Members
Data Type
Description
EnableOut
BOOL
Indicates if the instruction executed without fault when it was enabled.
Dest
REAL
Result of the instruction.
FBD Function
TIP:
FBD Function is applicable to CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers only.
Input Operands (Left Pins)
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers
Data Type
Description
SourceA (top)
SINT
USINT
INT
UINT
DINT
UDINT
LINT
ULINT
REAL
LREAL
Value of the multiplicand.
SourceB (bottom)
SINT
USINT
INT
UINT
DINT
UDINT
LINT
ULINT
REAL
LREAL
Value of the multiplier.
Output Operand (Right Pin)
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers
Data Type
Description
Dest
DINT
UDINT
LINT
ULINT
REAL
LREAL
Result of the function.
See
FBD Functions
.
Affects Math Status Flags
Controllers
Affects Math Status Flag
CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers
Conditional
CompactLogix 5370, ControlLogix 5570, Compact GuardLogix 5370, and GuardLogix 5570 controllers
Yes
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
Dest = Source A x Source B
Postscan
N/A
Function Block Diagram
Condition/State
Action Taken
Prescan
N/A
EnableIn is false
Set EnableOut to EnableIn
EnableIn is true
Dest = SourceA x SourceB
If overflow occurs
Clear EnableOut to false
else
Set EnableOut to true
Instruction first run
N/A
Instruction first scan
N/A
Postscan
N/A
FBD Function
TIP:
FBD Function is applicable to CompactLogix 5380, CompactLogix 5480, ControlLogix 5580, Compact GuardLogix 5380, and GuardLogix 5580 controllers only.
Condition/State
Action Taken
Prescan
N/A
Normal Scan
Dest = Source A x Source B
Instruction first run
N/A
Instruction first scan
N/A
Postscan
N/A
Examples
Ladder Diagram
MUL_LD_ex_v31
Function Block Diagram
FBD Block
FBD Function
Structured Text
REAL_dest := REAL_srcA * REAL_srcB;
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