Instruction Set

PLCLogix 500 features 65 instructions and PLCLogix 5000 has 80 instructions. These instructions encompass all of the main programming commands associated with either the Logix 500 or 5000 PLC. The PLCLogix Instruction Set consists of the following groups of commands: Bit Instructions, Timer and Counter Instructions, Program Control, Compare, Math, Advanced Math, Move/Logical, Array Shift and Sequencer Instructions.

Select the instruction set by choosing either PLCLogix 500 or 5000 in the Instruction Set Groups shown below:

Instruction Set Groups

Bit Instructions
Mnemonic	Name	Symbol	Description
XIC	Examine If Closed		Examines a bit for an On (set, high) condition.
XIO	Examine If Open		Examines a bit for an Off (cleared, low) condition.
OTE	Output Energize		When rung conditions are true, the OTE will either set or clear the data bit.
OTL	Output Latch		When enabled, the instruction signals to the controller to turn on the addressed bit. The bit remains on, regardless of the rung condition.
OTU	Output Unlatch		When enabled, it clears (unlatches) the data bit. The bit remains Off, regardless of rung condition.
ONS	One Shot		Enable/disable outputs for one scan when rung is true. The status of the storage bit determines whether this instruction enables or disables the rest of the rung.
OSR	One Shot Rising		This instruction is a retentive input instruction that triggers an event to occur once. It either sets or clears the output bit, depending on the storage bit status
OSR	One Shot Rising		This instruction is a retentive input instruction that triggers an event to occur once. It either sets or clears the output bit, depending on the storage bit status
OSF	One Shot Falling		This instruction either sets or clears the output bit, depending on the storage bit’s status.

Timer and Counter Instructions
Mnemonic	Name	Symbol	Description
TON	Timer On Delay		A non-retentive timer that accumulates time when the instruction is enabled. The accumulated value is reset when rung conditions go false.
TOF	Timer Off Delay		A non-retentive timer that accumulates time when the rung makes a true-to-false transition.
RTO	Retentive Timer On		A retentive timer that accumulates time when the instruction is enabled. Retains its accumulated value when rung conditions become false.
TON	Count Up		An instruction that counts false-to-true rung transitions. It counts upward and the accumulated value is incremented by one count on each of these transitions.
TOF	Count Down		This instruction counts downward on each false-to-true rung transition. The accumulated value is decremented by one count on each of these transitions.
RTO	Retentive Timer On		A retentive timer that accumulates time when the instruction is enabled. Retains its accumulated value when rung conditions become false.
CTU	Count Up		An instruction that counts false-to-true rung transitions. It counts upward and the accumulated value is incremented by one count on each of these transitions.
CTD	Count Down		This instruction counts downward on each false-to-true rung transition. The accumulated value is decremented by one count on each of these transitions.
RES	Reset		This instruction is used to reset a timer, counter or control structure. The accumulated value of these instructions are cleared when the RES instruction is enabled.

Program Control Instructions
Mnemonic	Name	Symbol	Description
JSR	Jump to Subroutine		This instruction jumps execution to a specific routine and initiates the execution of this routine, called a subroutine.
SBR	Subroutine		Stores recurring sections of program logic.
RET	Return		Used to return to the instruction following the a JSR operation.
JMP	Jump to Label		Skips sections of ladder logic.
LBL	Label		Target of the JMP instruction with the same label name.
MCR	Master Cont. Res.		Used in pairs to create a program zone that can disable all rungs between the MCR instructions.
AFI	Always False		Disables all instructions on a rung.
NOP	No Operation		This instruction functions as a placeholder.
TND	Temporary End		When enabled, it lets the controller execute logic only up to this instruction.
IOT	Immediate Output		This instruction immediately updates the specified output data.

Compare Instructions
Mnemonic	Name	Symbol	Description
EQU	Equal		This instruction is used to test whether two values are equal. If Source A is equal to Source B, the instruction is logically true.
GEQ	Greater Than or Equal To		Determines whether Source A is greater than or equal to Source B. If the value at Source A is greater than or equal to the value at Source B, then the instruction is true.
GRT	Greater Than		This instruction is used to test whether one value (Source A) is greater than another value (Source B).
LEQ	Less Than or Equal To		Determines whether one value (Source A) is less than or equal to another (Source B).
LES	Less Than		This instruction determines whether Source A is less than Source B.
LIM	Limit		This instruction is used to test for values within the range of the Low Limit to the High Limit.
MEQ	Mask Equal To		Passes the Source and Compare values through a Mask and compares the results.
NEQ	Not Equal To		This instruction tests whether Source A is not equal to Source B.

Math Instructions
Mnemonic	Name	Symbol	Description
ADD	Add		Adds Source A to Source B and stores the result in the Destination.
SUB	Subtract		Subtracts Source B from Source A and places the result in the Destination.
MUL	Multiply		Multiplies Source A by Source B and stores the result in the Destination.
DIV	Divide		Divides Source A by Source B and places the result in the Destination.
MOD	Modulo		Divides Source A by Source B and stores the remainder in the Destination.
SQR	Square Root		Calculates the square root of the source and places the integer result in the Destination.
NEG	Negate		Changes the sign (+, -) of the Source and stores the result in the Destination.
ABS	Absolute		Takes the absolute value of the Source and places the result in the Destination.
CPT	Compute		Performs the arithmetic operations defined in the Expression and stores the result in the Destination.

Math Conversions
Mnemonic	Name	Symbol	Description
TOD	Convert to BCD		This instruction converts a decimal value to a BCD value and stores the result in the Destination.
FRD	Convert to Integer		Converts a BCD value (Source) to a decimal value and stores the result in the Destination.
DEG	Degrees		Converts the Source (in radians) to degrees and places the result in the Destination.
RAD	Radians		Converts the Source (in degrees) to radians and stores the result in the Destination.
TRN	Truncate		Removes the fractional part of the Source and places the result in the Destination.

Advanced Math Instructions
Mnemonic	Name	Symbol	Description
SIN	Sine		Takes the sine of the Source value (in radians} and places the result in the Destination.
COS	Cosine		Takes the cosine of the Source value (in radians) and places the result in the Destination.
TAN	Tangent		Takes the tangent of the Source value (in radians) and stores the result in the Destination.
ASN	Arc Sine		Takes the arc sine of the Source value and places the result in the Destination (in radians).
ACS	Arc Cosine		Takes the arc cosine of the Source value and stores the result in the Destination (in radians).
ATN	Arc Tangent		Takes the arc tangent of the Source value and stores the result in the Destination (in radians).
LN	Natural Log		Takes the natural log of the Source value and stores the result in the Destination.
LOG	Log to the Base 10		Takes the log base 10 of the Source value and stores the result in the Destination.
XPY	X to the power Y		Takes Source A (X) to the power of Source B (Y) and stores the result in the Destination.

Move/Logical Instructions
Mnemonic	Name	Symbol	Description
MOV	Move		Copies the Source (which remains unchanged) to the Destination.
MVM	Masked Move		Copies the Source to a Destination and allows segments of the data to be masked.
CLR	Clear		Clears all the bits of the Destination.
DTR	Data Transitional		Passes the Source value through a Mask and compares the result with the Reference value.
SWPB	Swap Byte Instruction		Rearranges the bytes of a tag and stores the bytes in the new order.
SWP	Swap Byte Instruction		Swaps the lower and higher bytes of a specified number of words.
BTD	Bit Field Distribute		Copies the specified bits from the Source, shifts the bits to the appropriate position, and writes the bits into the Destination.
AND	Bitwise AND		Performs a logical AND operation by using the bits in Source A and Source B and placing the result in the Destination.
OR	Bitwise OR		Performs a logical AND operation by using the bits in Source A and Source B and placing the result in the Destination.
XOR	Bitwise Exclusive OR		Performs a bitwise XOR operation using the bits in Source A and Source B and stores the result in the Destination.
NOT	Bitwise NOT		Executes a bitwise NOT operation by using the bits in the Source and placing the result in the Destination

Array Shift Instructions
Mnemonic	Name	Symbol	Description
BSL	Bit Shift Left		Shifts the specified bits within the Array one position left.
BSR	Bit Shift Right		Shifts the specified bits within the Array one position right.
COP	Copy File		Copies the value in the Source to the Destination.
FLL	File Fill		Fills elements of an array with the Source value, while the Source remains unchanged.
AVE	File Average		Calculates the average of a set of values.
FFL	FIFO Load		Copies the Source Value into a FIFO stack on successive false-to-true transitions.
FFU	FIFO Unload		Unloads the Source value from the first position of the FIFO and stores that value in the Destination.
LFL	LIFO Load		Copies the Source value to the LIFO.
LFU	LIFO Unload		Unloads the value at .POS of the LIFO and stores 0 in that location.
SRT	File Sort		Sorts a set of values in one dimension of the Array into ascending order.
STD	File Standard Deviation		Calculates the standard deviation of a set of values in one dimension of the Array and stores the result in the Destination.
SIZ	Size in Elements		Determines the size of a dimension of an array and stores the number of elements in the specified dimension of the array
SIZE	Size in Elements		Determines the size of a dimension of an array and stores the number of elements in the specified dimension of the array

Sequencer Instructions
Mnemonic	Name	Symbol	Description
SQI	Sequencer Input		Detects when a step is complete in a sequence pair of SQO/SQI instructions.
SQO	Sequencer Output		Sets output conditions for the next step of sequence pair of SQO/SQI or SQO/SQC instructions.
SQL	Sequencer Load		Loads reference conditions into a sequencer array.
SQC	Sequencer Compare		Detects when a step is complete in a sequence pair of SQO/SQC instructions. RSLogix 500 instruction, supported by PLCLogix.

PID Instruction
Mnemonic	Name	Symbol	Description
PID	Proportional Integral Derivative		Uses an algorithm to control physical properties based on a Process variable that stores input values and a Control variable that represents the output value.

AOI Instruction
Mnemonic	Name	Description
AOI	Add-On Instruction	A collection of logic that contains a commonly used function or algorithm and cabe combined into a single instruction and enhance or extend the capabilities of the built-in instruction set.

UDT Instruction
Mnemonic	Name	Description
UDT	User Defined Data Type	A convenient method of combining all the storage required for a particular function in a single location, and enables easier reuse of code.

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