Mitsubishi Electronics FX1S manual Modifying a Constant, Misuse of the Modifiers

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FX Series Programmable Controllers

Devices in Detail 4

4.13.1Modifying a Constant

Constants can be modified just as easily as data registers or bit devices. If, for example, the constant K20 was actually written K20V the final result would equal:

K20 + the contents of V

Example:

K20

If V = 3276 then K20V ➭ V (3276) 3296

4.13.2Misuse of the Modifiers

Modifying Kn devices when Kn forms part of a device description such as KnY is not possible, i.e. while the following use of modifiers is permitted;

K3Z

K1M10V

Y20Z

Statements of the form:

K4ZY30

are not acceptable.

• Modifiers cannot be used for parameters entered into any of the 20 basic instructions, i.e. LD, AND, OR etc.

4.13.3 Using Multiple Index Registers

The use of multiple index registers is

sometimes necessary in larger programs or

programs which handle large quantities of

data. There is no problem from the PLC’s

point of view in using both V and Z registers

many times through out a program. The point

to be aware of is that it is som etimes

confusing for the user or a maintenance

X0

X1

X2

MOV K10 V

MOV K20 Z

person reading such programs, as it is not

always clear what the current value of V or Z

is.

Example:

V = 10 (K10)

Z = 20 (K20)

D5V = D15 (D5 + V = D5 + 10 = D15)

D15Z = D35 (D15 + Z = D15 + 20 = D35)

D40Z = D60 (D40 + Z = D40 + 20 = D60)

ADD D 5V D 15Z D40Z

M8000

MOV K0 V

X3

DADD D 0 D 2 D 4Z

Both V and Z registers are initially set to K10 and K20 respectively. The contents of D15 is added to that of D35 and store in D60.

V is then reset to 0 (zero) and both V and Z are used in the double word addition (DADD). The contents of D1, D0 are then added to D3, D2 and then finally stored in D25, D24.

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Contents Programming Manual Page FX Series Programmable Controllers ForewordFX Series Programmable Controllers FAX Back Combined Programming Manual J FX Series Programmable Controllers Hardware Warnings Software WarningsFX Series Programmable Controllers Contents STL Programming Applied Instructions Rotation And Shift Functions 30 to External FX Serial Devices Functions 80 to Execution Times And Instructional 10-1 Viii FX Series Programmable Controllers Chapter Contents Introduction OverviewWhat is a Programmable Controller? What do You Need to Program a PLC?Special considerations for programming equipment Current Generation CPU all versionsAssocciated Manuals Manual name Number FX Base Unit HardwareManual name Number FX DU, GOT and DM units Memo Basic Program Instructions FX Series Programmable ControllersBasic Program Instructions Detailed device information What is a Program?Outline of Basic Devices Used in Programming How to Read Ladder Logic ExampleProgram example Load, Load InverseOUT instruction Timer and Counter Variations OutDouble Coil Designation Use of dual coilsLast coil effect And, And Inverse Peripheral limitationsOr, Or Inverse ORILoad Pulse, Load Trailing Pulse Single Operation flags M2800 to M3071Pulse, And Trailing Pulse LDF ANF OUTOr Pulse, Or Trailing Pulse ORF ORBSequential processing limitations Or BlockBatch processing limitations Block ANB13 MPS, MRD and MPP MPS, MRD and MPP usageMultiple program examples Master Control and Reset MCRNested MC program example Set and Reset Resetting timers and counters16.1Basic Timers, Retentive Timers And Counters Timer, Counter Out & ResetRetentive timers Normal 32 bit Counters Bit countersAvailability of devices High Speed CountersPLF Leading and Trailing PulseInverse Usages for INVNo Operation No Operation20 End Program scanMemo STL Programming FX Series Programmable ControllersSTL Programming What is STL, SFC And IEC1131 Part 3? General noteLook Inside an STL How STL OperatesEach step is a program Embedded STL programs How To Start And End An STL ProgramCombined SFC Ladder representation Activating new statesReturning to Standard Ladder Initial StepsTerminating an STL Program Using SET to drive an STL coil Moving Between STL StepsOut is used for distant jumps Using OUT to drive an STL coilOUT is used for loops and jumps Rules and Techniques For STL programs Basic Notes On The Behavior Of STL programsT001 K20 K50 Method 2 Special Single Pulse Flags Single Signal Step ControlMethod 1 Using locking devices Restrictions on using applied instructions Restrictions Of Some Instructions When Used With STLUsing ‘jump’ operations with STL Using STL To Select The Most Appropriate Program STL OUT SETUsing STL To Activate Multiple Flows Simultaneously Limits on the number of branchesLimits on the number of branches General Rules For Successful STL Branching Instruction FormatGeneral Precautions When Using The FX-PCS/AT-EE Software Programming Examples Simple STL FlowIdentification of normally closed contacts SET STLPoints to note Selective Branch/ First State Merge Example ProgramFull STL flow diagram/program Advanced STL Use Devices in Detail FX Series Programmable ControllersDevices in Detail Available devices Configuration detailsInputs Device MnemonicAlias O/P OutputsDevice Mnemonic Y General Stable State Auxiliary Relays Auxiliary RelaysDevice Mnemonic M Battery Backed/ Latched Auxiliary Relays External loadsSpecial Diagnostic Auxiliary Relays Special Single Operation Pulse RelaysGeneral Stable State State Relays State RelaysDevice Mnemonic S Battery Backed/ Latched State Relays PLC FX 1S FX 1N FX 2NSTL/SFC programming Assigned statesMonitoring STL programs IST instructionAnnunciator Flags Device availability PointersJumping to the end of the program Device Mnemonic PNested levels Interrupt PointersAdditional applied instructions Pointer positionInput Interrupts Timer InterruptsRules of use Additional notes Driving special auxiliary relaysDisabling high speed counter interrupts Disabling Individual InterruptsDevice Mnemonic K Constant KConstant H Example device usage N/ADevice Mnemonic T TimersTimer accuracy Driving special auxiliary coils General timer operationSelectable Timers Using timers in interrupt or ‘CALL’ subroutines Retentive TimersTimer Accuracy Internal timer accuracyTimers Used in Interrupt and ‘CALL’ Subroutines ConditionHigh speed counters Setting ranges for countersCounters Device Mnemonic CBattery backed/latched counters General/ Latched 16bit UP CountersGeneral/ Latched 32bit Bi-directional Counters Battery backed/ latched countersSelecting the counting direction Basic high speed counter operation Further uses NoneDriving high speed counter coils Basic High Speed Counter OperationAvailability of High Speed Counters Input assignmentCounter Speeds Calculating the maximum combined counting speed on FX1S Direction setting Device specificationSetting range Using the SPD instructionRST 11.5 2 Phase Bi-directional Counters C246 to C250 Device size11.6 A/B Phase Counters C252 to C255 Example device usage None Data RegistersDevice Mnemonic D General Use Registers Data register updatesData retention Battery Backed/ Latched Registers Using the FX2-40AW/APUse of diagnostic registers Special Diagnostic RegistersFile Registers Special caution when using FX1SWriting to file registers Program memory registersExternally Adjusted Registers UsesDevice Mnemonic V,Z Index RegistersUse of Modifiers with Applied Instruction Parameters Available formsMisuse of the Modifiers Using Multiple Index RegistersModifying a Constant Bits, Words, BCD and Hexadecimal Bit Devices, Individual and GroupedAssigning grouped bit devices Moving grouped bit devicesAssigning I/O Word Devices Interpreting Word DataFX Series Programmable Controllers Binary Coded Decimal value= Error Word Data Summary14.4 Two’s Compliment Inverted7 Additional1Floating Point And Scientific Notation Some useful constantsScientific Notation Floating Point Format FLT