CJ2 CPU Unit Software User's Manual - CIP ETI

5 Understanding ProgrammingInstruction VariationsThe following variations are available for instructions to differentiate executing conditions and to refreshdata when the instruction is executed (immediate refresh).Variation Symbol DescriptionDifferentiation ON @ Instruction that differentiates when the execution condition turns ON.OFF % Instruction that differentiates when the execution condition turns OFF.Immediate refreshing ! Refreshes data in the I/O area specified by the operands or the SpecialI/O Unit words when the instruction is executed.@ MOVInstruction (mnemonic)Differentiation variationImmediate refresh variationExecution ConditionsThe following two types of basic and special instructions can be used.• Non-differentiated instructions: Executed every cycle• Differentiated instructions: Executed only once55-6 Instructions Non-differentiated InstructionsOutput instructions (Instructions That Require Input Conditions):These instructions are executed once every cycle while the execution conditions are satisfied (ON orOFF).Non-differentiatedoutput instructionInput Instructions (Logical Starts and Intermediate Instructions):These instructions read bit status, make comparisons, test bits, or perform other types of processingevery cycle. If the results are ON, power flow is output (i.e., the execution condition is turned ON).Non-differentiated input instructionExampleExampleMOV5-6-1 Basic Understanding of Instructions Input-differentiated InstructionsUpwardly Differentiated Instructions (Instruction Preceded by @)Output Instructions:The instruction is executed only during the cycle in which the execution condition changed from OFFto ON and are not executed in the following cycles.(@) Upwardly differentiatedinstructionExample1.02@MOVExecutes the MOV instruction once whenCIO 1.02 goes OFF → ON.CJ2 CPU Unit Software User’s Manual5-63