Mechanism of absolute rotary encoder. Rotary Encoders

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1 Mechanism of absolute rotary encoder Rotary Encoders 40

Gray to binary conversion by PLC is restricted by its program

2 Mechanism of absolute rotary encoder Rotary Encoders Gray to binary conversion by PLC etween TRD-N and D4-450,440/D2-250,240 Gray to binary conversion by PLC is restricted by its program execution speed. t 20 ms/scan, set the encoder speed to 8 rpm or less. 4

3 Mechanism of absolute rotary encoder Rotary Encoders etween TRD-N and D2-230 Gray to binary conversion by PLC is restricted by its execution speed. t 20 ms/scan, set the encoder speed to 8 rpm or less. 42

4 Chapter 5: Standard RLL Instructions - Number Conversion Gray Code (GRY) DS Used HPP Used DirectSOFT X The Gray code instruction converts a 6-bit gray code value to GRY a CD value. The CD conversion requires 0 bits of the accumulator. The upper 22 bits are set to 0. This instruction is designed for use with devices (typically encoders) that use the grey code numbering scheme. The Gray Code instruction will directly convert a gray code number to a CD number for devices having a resolution of 52 or 024 counts per revolution. If a device having a resolution of 360 counts per revolution is to be used you must subtract a CD value of 76 from the converted value to obtain the proper result. For a device having a resolution of 720 counts per revolution you must subtract a CD value of 52. In the following example, when X is ON the binary value represented by X0 X27 is loaded into the accumulator using the Load Formatted instruction. The gray code value in the accumulator is converted to CD using the Gray Code instruction. The value in the lower 6 bits of the accumulator is copied to V200. LDF X0 Handheld Programmer Keystrokes $ STR SHFT SHFT GX OUT K6 Load the value represented by X0 X27 into the lower 6 bits of the accumulator GRY Convert the 6 bit grey code value in the accumulator to a CD value OUT V200 Copy the value in the lower 6 bits of the accumulator to V200 L D NDST 3 G R 6 ORN SHFT ENT F 5 0 V ND Y MLS C 2 ENT 0 0 Gray Code CD X2 X X0 ON OFF ON cc cc ENT G 6 ENT X27 X26 X25 OFF OFF OFF V C D DL205 User Manual, 4th Edition, Rev. 5 4

5 GRY - Gray Code to Integer mk:@msitstore:c:\do-more%20designer\help\dmdesigner.chm::/instruction_set/gry_gray_co... Page of 2 0/29/202 Topic: DMD0024 GRY - Gray Code to Integer The Gray Code to Integer instruction (GRY) converts a 6 bit Gray code value to an integer value. This instruction is designed for use with devices that use the gray code numbering scheme. Gray codes are often used in linear encoders and rotary encoders in preference to straightforward binary encoding. This avoids the possibility that, when several bits change in the binary representation of an angle, a misread could result from some of the bits changing before others. Rotary encoders especially benefit from the cyclic nature of Gray codes, because the first and last values of the sequence differ by only one bit. The Gray Code to Integer instruction will directly convert a gray code number to an integer for devices having a resolution of 52 or 024 counts per revolution. For a device having a resolution of 360 counts per revolution you must subtract 76 from the converted value to obtain the correct result (360-Excess-76 Gray Code). For a device having a resolution of 720 counts per revolution you must subtract 52 from the converted value to obtain the correct result (720-Excess-52 Gray Code). Gray Code inary Decimal Parameters: 023 Note: Use the F9 key (Element rowser) or Down-rrow key (uto-complete) at any time to see a complete list of the memory locations that are valid in the current field of the instruction.

$GRY - Gray Code to Integer mk:@msitstore:c:\do-more%20designer\help\dmdesigner.chm::/instruction_set/gry_gray_co.$

6 GRY - Gray Code to Integer mk:@msitstore:c:\do-more%20designer\help\dmdesigner.chm::/instruction_set/gry_gray_co... Page 2 of 2 0/29/202 Input Value - designates the memory location that contains the Gray code value. This can be any constant value or any readable numeric location. Output Value - designates a memory location to store the converted value. This can be any writable numeric location. See lso: FREQCNT - Frequency Counter FREQTMR - Frequency Timer GRY - Gray Code to Integer SCLE - Scale Value SEG - Hex/CD to 7 Segment Display STR2INT - Convert String to Integer STR2REL - Convert String to Real SWP - Swap ytes Rung Example:

Topic: P220 and P44 Chapter 7: Instructions 2 3 4 5 6 7 8 9 0 2 3 4 C D Data Handling Purpose Instruction Parameters Instruction Configuration bsolute Encoder (SE) Instruction Mnemonic (Keyboard

7 Topic: P220 and P44 Chapter 7: Instructions C D Data Handling Purpose Instruction Parameters Instruction Configuration bsolute Encoder (SE) Instruction Mnemonic (Keyboard Shortcut) = SE Icon/utton = Decodes it Pattern from Gray Code or inary bsolute Encoder. Parameter Enable Encoder Type Encoder Counts Input Parameter Type Ladder Input Selectable Option Drop-down Menu Selection oolean Tag / Constant Requirements Must Have Note: The Output Tag Value is not forced to zero when the Enable is turned OFF. The Output Tag will contain the last value Written by the Instruction until it is overwritten by another Instruction or from an external device. Note: Tag Values are updated immediately as each Ladder Rung is executed, top to bottom. However, Tag Values representing physical Outputs are only applied to the physical Output after the END statement of the last Task to be scanned is reached. Outputs in Remote ase Groups have additional limitations regarding Update Intervals. When bsolute Encoder Instruction is selected the window shown on the right opens with defaults shown. Description Level-driven. When Enable is ON, the instruction will operate every scan. When Enable is OFF, instruction is not solved and its outputs are not updated. Selects Gray Code or inary Encoder type. Output Numerical Tag Current Encoder position. Selects one of these Resolutions for the bsolute Encoder: 32 pulses (5 bits) 52 pulses (9 bits) 64 pulses (6 bits) 720 pulses (0 bits) 28 pulses (7 bits) 024 pulses (0 bits) 80 pulses (8 bits) 2048 pulses ( bits) 256 pulses (8 bits) 4096 pulses (2 bits) 360 pulses (9 bits) Discrete Input Tags assigned to the bsolute Encoder Inputs. The number of required Tags depends on selected Encoder Counts Feedback to: docs@automationdirect.com Programming Software User Manual, st Ed., Rev.

Topic: P44 Chapter 7: Instructions pplication Example Rung Example bsolute Encoder (SE) Encoder Type Encoder Counts Input Output Parameter Configuration Table Notes: Select Gray Code or inary Encoder

8 Topic: P44 Chapter 7: Instructions pplication Example Rung Example bsolute Encoder (SE) Encoder Type Encoder Counts Input Output Parameter Configuration Table Notes: Select Gray Code or inary Encoder type. Select Encoder Resolution. Enter a Value or Tag for each Input. Select an Output Tag. In the following example, the current table position is calculated based on the Encoder Resolution and the bit pattern of the Gray Code bit pattern fed into the SE instruction C D Feedback to: docs@automationdirect.com Programming Software User Manual, st Ed., Rev. 7-39

Introduction. Getting Started. Getting Started. D2 HPP Handheld Programmer

Introduction. Getting Started. Getting Started. D2 HPP Handheld Programmer 1 2 Introduction D2 HPP Handheld Programmer The D2 HPP (Handheld Portable Programmer) is a general purpose tool for use with the DL105 or DL205 PLC products. It is well suited for performing basic PLC