Mitsubishi Electronics FX1S What is a Program?, Outline of Basic Devices Used in Programming

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FX Series Programmable Controllers

Basic Program Instructions 2

2.Basic Program Instructions

2.1What is a Program?

A program is a connected series of instructions written in a language that the PLC can understand. There are three forms of program format; instruction, ladder and SFC/STL. Not all programming tools can work in all programming forms. Generally hand held programming panels only work with instruction format while most graphic programming tools will work with both instruction and ladder format. Specialist programming software will also allow SFC style programming.

LD X10

OUT Y7

AND M38

SET S5

LD X21

OUT T01

K40

Instruction format

Ladder Format

SFC Format

2.2Outline of Basic Devices Used in Programming

There are six basic programming devices. Each device has its own unique use. To enable quick and easy identification each device is assigned a single reference letter;

-X: This is used to identify all direct, physical inputs to the PLC.

-Y: This is used to identify all direct, physical outputs from the PLC.

-T: This is used to identify a timing device which is contained within the PLC.

-C: This is used to identify a counting device which is contained within the PLC.

-M and S: These are used as internal operation flags within the PLC.

All of the devices mentioned above are known as ‘bit devices’. This is a descriptive title telling the user that these devices only have two states; ON or OFF, 1 or 0.

Detailed device information:

•Chapter 4 contains this information in detail. However, the above is all that is required for the rest of this chapter.

2-1

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Contents Programming Manual Page Foreword FX Series Programmable ControllersFX Series Programmable Controllers FAX Back Combined Programming Manual J FX Series Programmable Controllers Software Warnings Hardware 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 Overview IntroductionWhat do You Need to Program a PLC? What is a Programmable Controller?Current Generation CPU all versions Special considerations for programming equipmentManual name Number FX Base Unit Hardware Assocciated ManualsManual name Number FX DU, GOT and DM units Memo Basic Program Instructions FX Series Programmable ControllersBasic Program Instructions What is a Program? Outline of Basic Devices Used in ProgrammingDetailed device information Example How to Read Ladder LogicLoad, Load Inverse OUT instructionProgram example Out Timer and Counter VariationsUse of dual coils Last coil effectDouble Coil Designation Peripheral limitations And, And InverseORI Or, Or InverseSingle Operation flags M2800 to M3071 Load Pulse, Load Trailing PulseLDF ANF OUT Pulse, And Trailing PulseORF ORB Or Pulse, Or Trailing PulseOr Block Batch processing limitationsSequential processing limitations ANB BlockMPS, MRD and MPP usage 13 MPS, MRD and MPPMultiple program examples MCR Master Control and ResetNested MC program example Resetting timers and counters Set and ResetTimer, Counter Out & Reset Retentive timers16.1Basic Timers, Retentive Timers And Counters High Speed Counters Bit countersAvailability of devices Normal 32 bit CountersLeading and Trailing Pulse PLFUsages for INV InverseNo Operation No OperationProgram scan 20 EndMemo STL Programming FX Series Programmable ControllersSTL Programming General note What is STL, SFC And IEC1131 Part 3?How STL Operates Each step is a programLook Inside an STL Activating new states How To Start And End An STL ProgramCombined SFC Ladder representation Embedded STL programsInitial Steps Terminating an STL ProgramReturning to Standard Ladder Moving Between STL Steps Using SET to drive an STL coilUsing OUT to drive an STL coil OUT is used for loops and jumpsOut is used for distant jumps Basic Notes On The Behavior Of STL programs Rules and Techniques For STL programsT001 K20 K50 Single Signal Step Control Method 1 Using locking devicesMethod 2 Special Single Pulse Flags Restrictions Of Some Instructions When Used With STL Using ‘jump’ operations with STLRestrictions on using applied instructions STL OUT SET Using STL To Select The Most Appropriate ProgramLimits on the number of branches Using STL To Activate Multiple Flows SimultaneouslyLimits on the number of branches Instruction Format General Rules For Successful STL BranchingGeneral Precautions When Using The FX-PCS/AT-EE Software Simple STL Flow Programming ExamplesSET STL Identification of normally closed contactsSelective Branch/ First State Merge Example Program Points to noteFull STL flow diagram/program Advanced STL Use Devices in Detail FX Series Programmable ControllersDevices in Detail Device Mnemonic Configuration detailsInputs Available devicesOutputs Device Mnemonic YAlias O/P Auxiliary Relays Device Mnemonic MGeneral Stable State Auxiliary Relays External loads Battery Backed/ Latched Auxiliary RelaysSpecial Single Operation Pulse Relays Special Diagnostic Auxiliary RelaysState Relays Device Mnemonic SGeneral Stable State State Relays PLC FX 1S FX 1N FX 2N Battery Backed/ Latched State RelaysIST instruction Assigned statesMonitoring STL programs STL/SFC programmingAnnunciator Flags Device Mnemonic P PointersJumping to the end of the program Device availabilityPointer position Interrupt PointersAdditional applied instructions Nested levelsTimer Interrupts Rules of useInput Interrupts Disabling Individual Interrupts Driving special auxiliary relaysDisabling high speed counter interrupts Additional notesExample device usage N/A Constant KConstant H Device Mnemonic KTimers Timer accuracyDevice Mnemonic T General timer operation Selectable TimersDriving special auxiliary coils Retentive Timers Using timers in interrupt or ‘CALL’ subroutinesCondition Internal timer accuracyTimers Used in Interrupt and ‘CALL’ Subroutines Timer AccuracyDevice Mnemonic C Setting ranges for countersCounters High speed countersGeneral/ Latched 16bit UP Counters Battery backed/latched countersBattery backed/ latched counters Selecting the counting directionGeneral/ Latched 32bit Bi-directional Counters Further uses None Basic high speed counter operationBasic High Speed Counter Operation Driving high speed counter coilsInput assignment Counter SpeedsAvailability of High Speed Counters Calculating the maximum combined counting speed on FX1S Using the SPD instruction Device specificationSetting range Direction settingRST Device size 11.5 2 Phase Bi-directional Counters C246 to C25011.6 A/B Phase Counters C252 to C255 Data Registers Device Mnemonic DExample device usage None Data register updates Data retentionGeneral Use Registers Special Diagnostic Registers Using the FX2-40AW/APUse of diagnostic registers Battery Backed/ Latched RegistersProgram memory registers Special caution when using FX1SWriting to file registers File RegistersUses Externally Adjusted RegistersAvailable forms Index RegistersUse of Modifiers with Applied Instruction Parameters Device Mnemonic V,ZUsing Multiple Index Registers Modifying a ConstantMisuse of the Modifiers Bit Devices, Individual and Grouped Bits, Words, BCD and HexadecimalMoving grouped bit devices Assigning I/OAssigning grouped bit devices Interpreting Word Data Word DevicesFX Series Programmable Controllers Word Data Summary Binary Coded Decimal value= ErrorInverted7 Additional1 14.4 Two’s ComplimentSome useful constants Floating Point And Scientific NotationScientific Notation Floating Point Format FLT