Mitsubishi Electronics FX1S manual Restrictions Of Some Instructions When Used With STL

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FX Series Programmable Controllers

STL Programming 3

3.6Restrictions Of Some Instructions When Used With STL

Although STL can operate with most basic and applied instructions there are a few exceptions. As a general rule STL and MC-MCR programming formats should not be combined. Other instruction restrictions are listed in the table below.

 

 

Basic Instructions

 

 

LD, LDI, AND,

 

 

Operational State

ANI, OR,ORI,

ANB, ORB,

 

NOP, OUT,

MPS,MRD,

MC, MCR

 

 

SET, RST,

MPP

 

 

PLS,PLF

 

 

 

 

 

 

Initial and general

STL

 

 

 

 

 

 

states

 

 

 

SET S**

 

 

 

 

 

 

 

 

 

 

 

STL

 

 

 

 

Branch-

Output

 

SET S**

processing

 

ing and

 

 

 

 

 

 

 

 

 

 

 

merging

 

 

 

 

 

 

states

Transfer

STL

STL

 

 

 

 

 

processing

 

SET S**

 

STL

 

 

 

Restrictions on using applied instructions

Most applied instructions can be used within STL programs. Attention must be paid to the way STL isolates each non-active step. It is recommended that when applied instructions are used their operation is completed before the active STL step transfers to the next step.

Other restrictions are as follows:

-FOR - NEXT structures can not contain STL program blocks.

-Subroutines and interrupts can not contain STL program blocks.

-STL program blocks can not be written after an FEND instruction.

-FOR - NEXT instructions are allowed within an STL program with a nesting of up to 4 levels.

For more details please see the operational compatibility listed in the two tables on pages 7-12,7-13.

Using ‘jump’ operations with STL

• Although it is possible to use the program jump operations (CJ instruction) within STL program flows, this causes additional and often unnecessary program flow complications. To ensure easy maintenance and quick error finding it is recommended that users do not write jump instructions into their STL programs.

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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