What is a Program? | Mitsubishi Electronics FX1S specification

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.

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

Contents

Programming Manual Page Foreword FX Series Programmable Controllers FX Series Programmable Controllers FAX Back Combined Programming Manual J FX Series Programmable Controllers Software Warnings Hardware Warnings FX 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 Introduction What do You Need to Program a PLC? What is a Programmable Controller? Current Generation CPU all versions Special considerations for programming equipment Manual name Number FX Base Unit Hardware Assocciated Manuals Manual 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 Logic Load, Load Inverse OUT instructionProgram example Out Timer and Counter Variations Use of dual coils Last coil effectDouble Coil Designation Peripheral limitations And, And Inverse ORI Or, Or Inverse Single Operation flags M2800 to M3071 Load Pulse, Load Trailing Pulse LDF ANF OUT Pulse, And Trailing Pulse ORF ORB Or Pulse, Or Trailing Pulse Or Block Batch processing limitationsSequential processing limitations ANB Block MPS, MRD and MPP usage 13 MPS, MRD and MPP Multiple program examples MCR Master Control and Reset Nested MC program example Resetting timers and counters Set and Reset Timer, Counter Out & Reset Retentive timers16.1Basic Timers, Retentive Timers And Counters High Speed Counters Bit countersAvailability of devices Normal 32 bit Counters Leading and Trailing Pulse PLF Usages for INV Inverse No Operation No Operation Program scan 20 End Memo 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 programs Initial Steps Terminating an STL ProgramReturning to Standard Ladder Moving Between STL Steps Using SET to drive an STL coil Using 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 programs T001 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 Program Limits on the number of branches Using STL To Activate Multiple Flows Simultaneously Limits on the number of branches Instruction Format General Rules For Successful STL Branching General Precautions When Using The FX-PCS/AT-EE Software Simple STL Flow Programming Examples SET STL Identification of normally closed contacts Selective Branch/ First State Merge Example Program Points to note Full STL flow diagram/program Advanced STL Use Devices in Detail FX Series Programmable ControllersDevices in Detail Device Mnemonic Configuration detailsInputs Available devices Outputs Device Mnemonic YAlias O/P Auxiliary Relays Device Mnemonic MGeneral Stable State Auxiliary Relays External loads Battery Backed/ Latched Auxiliary Relays Special Single Operation Pulse Relays Special Diagnostic Auxiliary Relays State Relays Device Mnemonic SGeneral Stable State State Relays PLC FX 1S FX 1N FX 2N Battery Backed/ Latched State Relays IST instruction Assigned statesMonitoring STL programs STL/SFC programming Annunciator Flags Device Mnemonic P PointersJumping to the end of the program Device availability Pointer position Interrupt PointersAdditional applied instructions Nested levels Timer Interrupts Rules of useInput Interrupts Disabling Individual Interrupts Driving special auxiliary relaysDisabling high speed counter interrupts Additional notes Example device usage N/A Constant KConstant H Device Mnemonic K Timers Timer accuracyDevice Mnemonic T General timer operation Selectable TimersDriving special auxiliary coils Retentive Timers Using timers in interrupt or ‘CALL’ subroutines Condition Internal timer accuracyTimers Used in Interrupt and ‘CALL’ Subroutines Timer Accuracy Device Mnemonic C Setting ranges for countersCounters High speed counters General/ Latched 16bit UP Counters Battery backed/latched counters Battery backed/ latched counters Selecting the counting directionGeneral/ Latched 32bit Bi-directional Counters Further uses None Basic high speed counter operation Basic High Speed Counter Operation Driving high speed counter coils Input assignment Counter SpeedsAvailability of High Speed Counters Calculating the maximum combined counting speed on FX1S Using the SPD instruction Device specificationSetting range Direction setting RST Device size 11.5 2 Phase Bi-directional Counters C246 to C250 11.6 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 Registers Program memory registers Special caution when using FX1SWriting to file registers File Registers Uses Externally Adjusted Registers Available forms Index RegistersUse of Modifiers with Applied Instruction Parameters Device Mnemonic V,Z Using Multiple Index Registers Modifying a ConstantMisuse of the Modifiers Bit Devices, Individual and Grouped Bits, Words, BCD and Hexadecimal Moving grouped bit devices Assigning I/OAssigning grouped bit devices Interpreting Word Data Word Devices FX Series Programmable Controllers Word Data Summary Binary Coded Decimal value= Error Inverted7 Additional1 14.4 Two’s Compliment Some useful constants Floating Point And Scientific Notation Scientific Notation Floating Point Format FLT