~-
`
`~ I
`
`I
`I
`
`Mfiabbb
`
`Page]T0f296:
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`RA V./AMS
`E%.1022
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`

`
`ALLEN·BRADLEY
`
`IMC-201
`Single-Axis Motion Controller
`
`GML V3.3 Programming Manual
`Firmware 2050x4.0, 17 June 1993, PIN 999-111
`
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`

`
`COPYRIGHT
`
`© 1993 by Allen-Bradley Company, Inc. All rights reserved. No part of
`this publication may be reproduced, transmitted, transcribed, stored in a
`retrieval system, or translated into any language in any form by any
`means without the express written permission of Allen-Bradley.
`
`DISCLAIMER
`
`The information contained in this document is subject to change without
`notice and should not be construed as a commitment by Allen-Bradley.
`Allen-Bradley assumes no responsibility for any errors that may appear.
`
`TRADEMARKS
`
`IBM-PC is a registered trademark of International Business Machines
`Corporation.
`MS-DOS is a registered trademark of Microsoft.
`
`Printed in USA
`
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`
`GML Programming Manual for IMC-201
`
`1
`
`TABLE OF CONTENTS
`
`Getting Started
`
`The Expression
`Builder
`
`Function Block
`Reference
`
`Introduction ............................................................................................ 1
`Configure the Workshop ........................................................................ 2
`The Definitions Menu ............................................................................ 3
`Hardware Options ..................................................................... 4
`Axis Use ..................................................................................... 6
`User Variables .......................................................................... 12
`General Purpose Inputs ........................................................... 16
`General Purpose Outputs ........................................................ 18
`General Purpose Input Groups ............................................... 20
`General Purpose Output Groups ............................................. 24
`RIO Inputs ................................................................................ 28
`RIO Outputs ............................................................................. 30
`RIO Input Groups ..................................................................... 32
`RIO Output Groups .................................................................. 36
`User Flags ................................................................................. 40
`User Constants ......................................................................... 42
`Display Configuration .............................................................. 44
`Display Fields ........................................................................... 4 7
`Communications ....................................................................... 54
`Documentation ......................................................................... 55
`
`Introduction ........................................................................................... 57
`The Calculator ....................................................................................... 61
`Expression Operators ........................................................................... 62
`Mathematical Operators .......................................................... 62
`Logical Operators ..................................................................... 64
`System Variables ................................................................................... 66
`Motion Variables ...................................................................... 66
`Other Controller Variables ...................................................... 7 4
`User Variables and Constants .............................................................. 76
`System Functions .................................................................................. 77
`Inputs and Outputs ............................................................................... 82
`
`Introduction ........................................................................................... 83
`Direct Control Blocks ............................................................................ 83
`Feedback On ............................................................................. 84
`Feedback Off ............................................................................. 84
`Set Output Limit ...................................................................... 85
`Wait For Output Limit ............................................................. 86
`Change Gain ............................................................................. 87
`Direct Drive Control ................................................................. 88
`Clear Axis .Fault ....................................................................... 88
`Redefine Position ...................................................................... 89
`
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`
`11
`
`GML Programming Manual for IMC-201
`
`Motion Blocks ........................................................................................ 91
`Set Motion Profile .................................................................... 92
`Set Maximum Velocity ............................................................. 94
`Set Maximum Accel ................................................................. 94
`Set Maximum Decel ................................................................ 94
`Home Axis ................................................................................ 95
`Move Axis ................................................................................. 98
`Jog Axis .................................................................................. 106
`Gear Axes ................................................................................ 107
`Configure Cam ....................................................................... 111
`Time Lock Cam ...................................................................... 114
`Position Lock Cam ................................................................. 115
`Disable PCAM ........................................................................ 119
`Wait for Done ......................................................................... 120
`Wait For Axis Lock ................................................................ 121
`Wait for Accelerated .............................................................. 122
`Wait for Homed ...................................................................... 122
`Wait for Gearing .................................................................... 123
`Change Dynamics .................................................................. 124
`Disable Gearing ..................................................................... 125
`Stop Motion ............................................................................ 126
`I/0 and Event Blocks .......................................................................... 128
`Output On .............................................................................. 128
`Output Off .............................................................................. 128
`Wait for Input On .................................................................. 129
`Wait for Input Off .................................................................. 130
`Set Timer ................................................................................ 131
`Wait for Timeout .................................................................... 131
`Set Registration ..................................................................... 132
`Wait for Registration ............................................................. 135
`Set Watch Position ................................................................. 136
`Wait for Position .................................................................... 137
`Status Blocks ...................................................................................... 138
`Show Axis Position ................................................................ 138
`Axis Status ............................................................................. 139
`Registration Status ................................................................ 140
`Position Status ....................................................................... 140
`Home Status ........................................................................... 141
`Lock Status ............................................................................. 141
`Output Limit Status .............................................................. 142
`Input Status ........................................................................... 143
`Memory Status ....................................................................... 144
`Communication Blocks ....................................................................... 146
`Serial Port Override .............................................................. 146
`Query Slave Control .............................................................. 14 7
`Show RIO Status .................................................................... 149
`Wait for RIO Status ............................................................... 149
`If RIO Status .......................................................................... 150
`Wait for RIO Block Transfer ................................................. 152
`If RIO Block Transfer ............................................................ 154
`Reset RIO ............................................................................... 154
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`
`Table of Contents
`
`111
`
`Conditional and Program Control Blocks ......................................... 155
`Repeat Loop ........................................................................... 155
`If Axis Status ......................................................................... 156
`If Fault ................................................................................... 162
`If Homed: ............................................................................... 163
`If Locked ................................................................................ 164
`If Accelerating ....................................................................... 165
`If Gearing ............................................................................... 167
`If Input ................................................................................... 168
`If Timeout .............................................................................. 169
`If Registration ....................................................................... 169
`If Position ............................................................................... 1 70
`If Output Limit ...................................................................... 170
`If Flag ...................................................................................... 171
`End Program.......................................................................... 1 71
`When End Program ............................................................... 172
`Calculation Blocks .............................................................................. 173
`Equation ................................................................................ 173
`If Expression .......................................................................... 175
`Store to Memory .................................................................... 1 77
`Get from Memory .................................................................. 177
`Build Table ............................................................................ 178
`Display and Operator Interface Blocks ............................................. 183
`Print to Display ..................................................................... 183
`Edit Value .............................................................................. 186
`Toggle Choice ......................................................................... 188
`Wait for Key ........................................................................... 191
`If Key ...................................................................................... 193
`Interrupt Editing ................................................................... 195
`Refresh Display ..................................................................... 195
`Adjust Auto Display .............................................................. 196
`Enter Setup Menu ................................................................. 198
`Enter Runset Menu ............................................................... 198
`Alarm and Event Action Blocks ........................................................ 199
`Set Alarm ............................................................................... 199
`Cancel Alarm ......................................................................... 201
`Registration Event Action ..................................................... 202
`Cancel Registration ............................................................... 203
`Position Event Action ........................................................... 204
`Cancel Watch Position .......................................................... 205
`Flag Control Blocks ............................................................................ 206
`Set Flag .................................................................................. 206
`Clear Flag .............................................................................. 206
`Wait for Flag Set ................................................................... 207
`Wait for Flag Cleared ............................................................ 207
`Multitasking Blocks ............................................................................ 208
`Start New Task ...................................................................... 210
`Stop Current Task ................................................................. 211
`Stop Other Task .................................................................... 211
`Stop Dispatcher ..................................................................... 212
`Restart Dispatcher ................................................................ 212
`
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`
`lV
`
`GML Programming Manual for IMC-201
`
`Appendix A
`
`AppendixB
`
`Analog Control Blocks ........................................................................ 213
`Analog Control Loop .............................................................. 213
`Analog Input Event Action .................................................... 216
`Clear Analog Monitor ............................................................ 217
`Miscellaneous Blocks .......................................................................... 218
`Adjust Control Setting ........................................................... 218
`Show Control Setting ............................................................. 222
`Patch ....................................................................................... 222
`Debug Breakpoint .................................................................. 223
`Show Firmware ID ................................................................ 223
`New Module ........................................................................... 223
`
`ASCII Reference .................................................................................. 225
`
`A CC EL Reference ............................................................................... 227
`User Variables ....................................................................... 227
`Internal Variables .................................................................. 227
`Functions ................................................................................ 228
`Expressions ............................................................................ 231
`Strings .................................................................................... 232
`Direct Commands .................................................................. 232
`Program Flow Commands ..................................................... 254
`Conditional Branch Commands ............................... 256
`System Commands ................................................................ 267
`
`AppendixC
`
`Data Parameter Reference ................................................................. 269
`
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`

`
`Getting Started
`
`1
`
`GETTING STARTED
`
`Introduction
`
`GML-the exclusive Graphical Motion Control Language from
`Allen-Bradley-is a revolutionary tool which reduces the learning
`curve of motion control programming and makes problem-solving eas(cid:173)
`ier for non-programmers.
`
`GML uses a natural, flowchart-oriented approach to motion con(cid:173)
`trol programming. A diagram of the desired application solution is
`produced by placing function blocks representing the desired actions
`on the screen and connecting them in the proper order to achieve the
`desired sequence of operations. Motion and process details are en(cid:173)
`tered later using a fill-in-the-form approach. The complete GML dia(cid:173)
`gram is then translated into an application program and downloaded
`to an IMC-201 motion controller for execution. This manual provides
`detailed information on using GML for programming the IMC-201
`·
`motion controller.
`
`GML Programmer's Workshop provides an integrated software
`development and debugging environment for using GML to solve your
`motion control problem. GML Programmer's Workshop includes facil(cid:173)
`ities for drawing and editing diagrams and an Online Manager which
`allows you to communicate directly with an IMC-201 motion con(cid:173)
`troller for setup and diagnostics.
`
`Development of the GML diagram is carried out using the GML
`Programmer's Workshop software running on your MS-DOS PC or
`Macintosh computer. See the GML Programmer's Workshop User's
`Manual (PIN 999-101) for information on using the workshop tools to
`create, edit, translate, download, save, and print diagrams.
`
`A Word to
`the Wise
`
`GML is designed to reduce the learning curve of motion control
`programming and make problem solving easier for non-programmers.
`Make no mistake, however-you still need a basic understanding of
`the problem you are trying to solve and how to use GML to solve it.
`Advanced planning is necessary; GML cannot divine the functions
`and operations you need to solve your particular application problem.
`
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`
`2
`
`GML Programming Manual for IMC-201
`
`Configure the
`Workshop
`
`Before starting your GML diagram, take a few moments to con(cid:173)
`figure GML Programmer's Workshop for proper operation with your
`motion controller.
`
`Choose Preferences from the File menu and then choose
`MAX/IMC-201 Family from the Control Family pop-up menu as
`shown below.
`
`~Control Family
`~MRH/IMC-201 Family
`
`Set any other preferences to your requirements, and then click OK or
`Save to close the Preferences window. OK stores your preferences as
`part of the current GML diagram only, while Save stores them in a
`separate GML Preferences file as well. See the GML Programmer's
`Workshop User's Manual (999-101) for more information on GML
`preferences.
`
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`

`
`Getting Started: The Definitions Menu
`
`3
`
`The Definitions
`Menu
`
`The Definitions menu is used to define the configuration of the
`specific motion controller you are using. As shown below, menu
`choices let you define how you are using the available motion axes,
`variables, discrete I/0, flags, etc. Each menu choice is explained be(cid:173)
`low.
`
`Definitions
`Hardware Options •..
`RHiS Use •••
`User Uariables ...
`General Purpose Inputs ...
`General Purpose Outputs ••.
`Gen. Purpose Input Groups •••
`Gen. Purpose Output Groups ..•
`RIO Inputs •..
`RIO Outputs ..•
`RIO Input Groups •..
`RIO Output Groups •.•
`User Flags •..
`User Constants ...
`Display Configuration ..•
`Display Fields ...
`Communications ...
`Documentation ..•
`
`NOTE: Be sure to
`set up at least the.
`Hardware Options and
`Documentation Defini(cid:173)
`tions before starting
`vour GML dia_aram.
`
`While most of the items in the Definitions menu need not be de(cid:173)
`fined until used, the following ones should be defined before starting
`your GML diagram to ~void later confusion and problems.
`
`• Hardware Options
`• Documentation
`
`See Hardware Options and Documentation later in this section for
`information on defining these items.
`
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`

`
`4
`
`Hardware
`Options
`
`GML Programming Manual for IMC-201
`
`The Hardware Options choice in the Definitions menu defines the
`specific motion controller you are using and any options it includes.
`Hardware Options should be defined prior to starting your GML dia(cid:173)
`gram to ensure that all the features of your specific motion controller
`are available within GML.
`
`Click the appropriate button to select the IMC-201 and choose 4.0
`(or later) from the AOS Version pop-up menu as shown below.
`
`Control Type ® I MC-201
`QMRH
`QMRH4
`I 4.0
`..,...,
`
`ROS Uersion
`
`AOS stands for ACCEL Operating System, which is the name of
`the firmware on the motion controller. The AOS version number se(cid:173)
`lected in the Hardware Options Definition must match the AOS ver(cid:173)
`sion on the motion controller to be used, otherwise all the capabilities
`of the motion controller may not be accessible through GML. The
`IMC-201 always uses AOS Version 4.0 or later.
`
`Cam Profiling
`
`If you plan to use the electronic cam feature of the IMC-201 in
`your application, select Cam Profiling as shown below.
`
`181 Cam Profiling
`
`If you do not need electronic cams in your application, do not select
`Cam Profiling.
`
`TI0-4848
`
`If you are using an optional TI0-4848 Thumbwheel and 1/0
`Expander with the motion controller in your application, select TI0-
`4848 Expanded 1/0 as shown below.
`
`181Tl0-4848 EHpanded I /O
`
`If you are not using a TI0-4848 in your application, do not select this
`option.
`
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`

`
`Getting Started: The Definitions Menu
`
`5
`
`TWP-1584
`
`If you are using an optional TWP-1584 Thumbwheel Panel with
`the motion controller in your application, select TWP-1584
`Thumbwheel Panel as shown below.
`181 TWP-1584 Thumbwheel Panel
`
`If you are not using a TWP-1584 in your application, do not select this
`option.
`
`SBX-RIO
`
`SBX-•.•
`
`IMC-201x-R models include an Allen-Bradley Remote 1/0
`Adapter. This option allows certain aspects of the IMC-201 to be con(cid:173)
`trolled and monitored from an Allen-Bradley PLC using a Remote 1/0
`Scanner. If you are using an IMC-201x-R model motion controller, se(cid:173)
`lect SBX-RIO as shown below.
`181 SBH-RIO
`
`If you are using an IMC-201x model motion controller, do not select
`this option, since your motion controller does not include the optional
`Remote 1/0 Adapter.
`
`The IMC-201 motion controller does not use the SBX-G2, SBX(cid:173)
`AI412, or SBX-G2Al412 options available with other members of the
`MAX Control Family and shown in the SBX- pop-up menu. Deselect
`the SBX- check box as shown below.
`
`0 SBH-
`
`G2
`
`.....,
`
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`
`6
`
`Axis Use
`
`WARNING: Always
`review the setup para(cid:173)
`meters using the IMC-
`201 Setup Menus affer
`downloading a new
`application program
`(generated from the
`GML diagram) to the
`motion controller .
`
`GML Programming Manual for IMC-201
`
`The Axis Use choice in the Definitions menu defines how you are
`using the available motion axes on your motion controller. Each axis
`can be named and configured as required for your application using
`the Axis Use definition. While axes need not be defined prior to start(cid:173)
`ing your GML diagram, if you know which axis on the motion con(cid:173)
`troller (hardware axis) will be used for what function in your applica(cid:173)
`tion, defining the axes before starting your GML diagram can save
`time and confusion later.
`
`To configure an axis, select the desired hardware axis from the
`list in the Axis Configuration window and click the Edit button. Enter
`a name for this axis (up to 10 characters) and define the axis using
`the pop-up menus and data entry boxes as explained below. After
`configuring all the axes required for your application, click Done to
`close the Axis Use window.
`
`When the application program (generated from the GML dia(cid:173)
`gram) is downloaded to the motion controller, the axis configuration
`entered using the Axis Use definition may change the Setup Menus in
`the motion controller by enabling or disabling certain prompts.
`Always review the setup parameters for all axes after downloading a
`new GML diagram to ensure proper operation.
`
`The IMC-201 provides two axes called the X Axis and the Y Axis.
`The X Axis is the servo controlled axis and the Y Axis is a master en(cid:173)
`coder input. See the Installation and Hookup section of the IMC-201
`Installation and Setup Manual for information on connecting the mo(cid:173)
`tion controller axes to servo drives, encoders, etc.
`
`For example, to configure the X Axis, select X as shown below and
`click Edit.
`
`./H
`y
`z
`w
`
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`

`
`Getting Started: The Definitions Menu
`
`7
`
`Naming an Axis
`
`Each axis should be given a name representing its function in
`your application. This name is used within the GML blocks to identify
`the axis. Enter a name for the axis in the Axis Name data entry box.
`
`For example, if the X Axis in your application controls a rotary
`cutter, you might name it "Cutter'', as shown below.
`
`H aHis name I Cutter
`
`Up to 10 upper or lower case letters or numbers may be used for
`the axis name, but the first character must be a letter. Do not use
`spaces or underline (_) characters in the name.
`
`Axis Use
`
`Each axis in the motion controller may be independently enabled
`or Disabled as required. In addition, enabled axes may be configured
`as either a full closed-loop Servo axis or for position monitoring only
`(Master Only). Choose the desired use of the axis from the Use pop-up
`menu.
`
`NOTE: Disabled
`axes need not be con(cid:173)
`figured, other than
`choosing Disabled from
`the Use menu.
`
`·The X Axis of the IMC-201 is the servo controlled axis. Thus the X
`Axis should be configured as a full Servo axis for most applications.
`Choose Servo from the Use pop-up menu as shown below
`
`Use
`
`Seruo
`
`to configure the X Axis as a full servo axis. If only the encoder input of
`the X Axis is to be used (to monitor position for example), choose
`Master Only from the Use pop-up menu.
`
`The Y Axis of the IMC-201 is only an encoder input which is nor(cid:173)
`mally used as the master axis for electronic gears and cams. Thus the
`Y Axis should be configured as a Master Only axis for most applica(cid:173)
`tions. Choose Master Only from the Use pop-up menu as shown below
`Master Only •I
`
`Use
`
`to configure the Y Axis. If you are not using the Y Axis in your appli(cid:173)
`cation, it should be disabled.
`
`All hardware axes which are not used in your application should
`be Disabled. With the IMC-201, the Zand Waxes should always be
`disabled. Choose Disabled from the Use pop-up menu as shown below
`
`Use
`
`Disabled
`
`to disable the Z and W axes. The X and Y axes may also be disabled if
`one or the other is not required in your application.
`
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`
`8
`
`GML Programming Manual for IMC-201
`
`Transducer
`
`If you are using an incremental encoder (or a synthesized incre-
`mental encoder signal from a servo drive) for feedback with this axis,
`choose Incremental Encoder from the Transducer pop-up menu as
`shown below.
`Transducer
`
`Inc. Encoder ...,.,
`
`In general, always choose Incremental Encoder unless you are specifi(cid:173)
`cally using one of the Allen-Bradley transducer converters discussed
`below.
`
`Choose REC-4096 from the Transducer pop-up menu as shown
`below
`I REC-4096
`
`Transducer
`
`...,.,
`
`if you are using an Allen-Bradley REC-4096 Resolver-to-Encoder
`Converter to interface a resolver to this axis.
`
`Choose TEC-242 from the Transducer pop-up menu as shown be(cid:173)
`low
`I TEC-242
`
`Transducer
`
`...,.,
`
`if you are using an Allen-Bradley TEC-242 Temposonics™-to-Encoder
`Converter to interface a magnetostrictive transducer to this axis.
`
`Choose AEC-216 from the Transducer pop-up menu as shown be(cid:173)
`low
`I REC-216
`
`Transducer
`
`...,.,
`
`if you are using an Allen-Bradley AEC-216 Absolute-to-Incremental
`Encoder Converter to interface an absolute encoder to this axis.
`
`Axis Mode
`
`All Servo or Master Only axes must be ·configured as either
`Linear or Rotary axes. Choose Linear from the Mode pop-up menu as
`shown below
`
`Mode
`
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`

`
`Getting Started: The Definitions Menu
`
`9
`
`NOTE: Always
`choose Linear unless
`you specifically need
`the Electronic Unwind
`feature of rotary axes.
`
`to configure this axis as a linear axis. In general, always choose
`Linear unless you specifically need the Electronic Unwind feature of
`rotary axes as discussed below.
`
`Choose Rotary from the Mode pop-up menu as shown below
`
`Position Units
`
`Mode
`
`ROTARY
`
`.,...,
`
`to configure this axis as a rotary axis. Rotary axes use a feature called
`Electronic Unwind to provide infinite position range by electronically
`"unwinding" the axis position whenever the axis moves through a
`complete physical revolution. In general, do not choose Rotary unless
`you specifically need the Electronic Unwind feature ofrotary axes.
`
`Rotary Axes require an Unwind value in the Machine Setup
`Menu of the motion controller to specify the position at which the axis
`is unwound.
`
`The IMC-201 allows user-defined engineering units rather than
`feedback counts to be used for measuring and programming all mo(cid:173)
`tion-related values (position, velocity, etc.). These Position Units or
`User Units can be different for each axis and should be chosen for
`maximum ease of use in your application. For example, linear axes
`might use Position Units of Inches, Meters, or mm while rotary axes
`might use units of Revs or Degrees.
`
`Enter the text string to be used in the Machine and Servo Setup
`Menus of the motion controller to request values for motion-related
`parameters in the Units data entry box. A maximum of eight charac(cid:173)
`ters may be used.
`
`For example, to use position units of millimeters for this axis, en(cid:173)
`ter mm in the Units data entry box as shown below.
`
`Units
`
`... I m_m _____ __.
`
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`

`
`10
`
`GML Programming Manual for IMC-201
`
`Display
`Format
`
`The Runtime Display as well as the Machine and Setup Menus in
`the motion controller use fixed length fields to display and enter all
`motion-related values (position, velocity, etc.). Enter the desired
`Display Format for the axis using the# character as a place holder.
`Use a decimal point (.) as required if fractional information is to be
`displayed.
`
`For example, a Display Format of
`
`Display
`Format
`
`I+••·····
`
`might be appropriate for a Linear axis using Position Units of mil(cid:173)
`limeters. With this Display Format, positions between ±9,999.99 mm
`(10 meters) can be displayed with a resolution of ±0.01 mm.
`
`The number of characters used to display axis position, velocity,
`acceleration, and deceleration in the Runtime Display and the Setup
`Menus is always the same (the total number of characters in the dis(cid:173)
`play format plus 1 for the sign) regardless of the value. Leading
`spaces and trailing zeros are automatically added to fill out the
`defined format. Note that the Display Format affects the values dis(cid:173)
`played in the Runtime Display, the Setup Menus, and the values
`which may be used in GML blocks.
`
`If axis position, velocity, acceleration, or deceleration ever become
`too large to be displayed using the defined display format, a field of Xs
`is displayed. For example, using the display format from the example
`above, if the current position o