11.6 A/B Phase Counters C252 to C255 | Mitsubishi Electronics FX1S

FX Series Programmable Controllers

Devices in Detail 4

4.11.6A/B Phase Counters (C252 to C255)

With these counters only the input identified in the previous high speed counter tables can be used for counting. The counting performed by these devices is independent of the program cycle (scan) time. Depending on the counter used, start, reset and other associated inputs are automatically allocated.

The A phase, B phase input signal not only pro vide th e co un ted sig na ls b ut the ir relationship to each other will also dictate the counted direction.

While the wave form of the A phase is in the ON state and...

the B phase moves from OFF to ON the counter will be counting up.

However, if...

the B phase moves from ON to OFF the counter will be in a down configuration.

One count is registered after both A and B phase inputs have been given and released in the correct order.

C251 counts the ON/OFF events of input X0 (the A phase input) and input X1 (the B phase input) while X11 is ON.

C255 starts counting immediately when X7 is turned ON while X13 is ON. The counting inputs are X3 (A phase) and X4 (B phase).

C255 is reset when X5 is turned ON. It can also be reset with X12 in the sequence.

Up-count

A-phase

B-phase

Down-count A-phase

B-phase

X10

			RST		C251
			RST		C251
X11					C251


X12					K1234
			RST		C255
			RST		C255

X13

C255

D0

Device specification:

•A maximum of 2 points - 2 phase, 32bit, up/down counters can be used. The operation of the output contact in relation to the counted data is the same as standard 32bit counters described in section 4.11.

Setting range:

•-2,147,483,648 to +2,147,483,647

Direction setting:

•Check the corresponding special relay M8✰✰✰ to determine if the counter is counting up or down.

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Mitsubishi Electronics FX1S manual 11.6 A/B Phase Counters C252 to C255

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 Outline of Basic Devices Used in Programming What is a Program?Detailed device information Example How to Read Ladder Logic OUT instruction Load, Load InverseProgram example Out Timer and Counter Variations Last coil effect Use of dual coilsDouble 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 Batch processing limitations Or BlockSequential 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 Retentive timers Timer, Counter Out & Reset16.1Basic 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? Each step is a program How STL OperatesLook Inside an STL Activating new states How To Start And End An STL ProgramCombined SFC Ladder representation Embedded STL programs Terminating an STL Program Initial StepsReturning to Standard Ladder Moving Between STL Steps Using SET to drive an STL coil OUT is used for loops and jumps Using OUT to drive an STL coilOut is used for distant jumps Basic Notes On The Behavior Of STL programs Rules and Techniques For STL programs T001 K20 K50 Method 1 Using locking devices Single Signal Step ControlMethod 2 Special Single Pulse Flags Using ‘jump’ operations with STL Restrictions Of Some Instructions When Used 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 Device Mnemonic Y OutputsAlias O/P Device Mnemonic M Auxiliary RelaysGeneral Stable State Auxiliary Relays External loads Battery Backed/ Latched Auxiliary Relays Special Single Operation Pulse Relays Special Diagnostic Auxiliary Relays Device Mnemonic S State RelaysGeneral 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 Rules of use Timer InterruptsInput 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 Timer accuracy TimersDevice Mnemonic T Selectable Timers General timer operationDriving 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 Selecting the counting direction Battery backed/ latched countersGeneral/ Latched 32bit Bi-directional Counters Further uses None Basic high speed counter operation Basic High Speed Counter Operation Driving high speed counter coils Counter Speeds Input assignmentAvailability 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 Device Mnemonic D Data RegistersExample device usage None Data retention Data register updatesGeneral 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 Modifying a Constant Using Multiple Index RegistersMisuse of the Modifiers Bit Devices, Individual and Grouped Bits, Words, BCD and Hexadecimal Assigning I/O Moving grouped bit devicesAssigning 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