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--- mycnc:linear_encoder_setup [2019/12/05 13:07] – ivan
+++ mycnc:linear_encoder_setup [2021/03/11 15:06] (current) – ivan
@@ Line 28: / Line 28: @@
 {{:mycnc:encoders-003-m4e.png}}
+====Step-by-step setup example====
+THIS SECTION OF THE MANUAL IS A WORK-IN-PROGRESS. Please contact the myCNC Support Team should any questions arise.
+Going through the setup process for linear encoder feedback one step at a time:
+.
+In this step, we want to make sure that the PID number, motor output and encoder channel number are equal (the current implementation requires that they should always be "lined up" in such a manner)
+For example:
+^ PID ^ Motor ^ Encoder # ^
+| PID0 | Motor0 | Encoder0 |
+| PID1 | Motor1 | Encoder1 |
+| PID2 | Motor2 | Encoder2 |
+It is possible to customize these arbitrarily, but as of the time of writing this manual (November 2020) it is strongly discouraged.
+{{:mycnc:linear-encoders-001.png}}
+.
+Registers for displaying the magnitude of the PID error are registers 9016, 9017, 9018, 9019, etc for PIDs 0, 1, 2, 3, etc respectively,
+.
+X1366M4E profile should be used when working with linear encoders and PIDs.
+For PID tuning, it is recommended to output these registers to display the error value on the error indicator
+and on the corresponding "oscillograms" that will be visible to the user.
+The following XML files are modified from the original implementation.
+. Error magnitude display is done via the following block of code in the ''coordinates-4.xml'' file
+<code XML><!--Encoder values -->
+<gitem where="x-coordinates" position="74;40" width="120" height="30"
+ displayAlignment="left;vcenter"
+ fgColor="##f-machinepos" format="%8.3f" fontFamily="Open Sans"
+ fontSize="16" type="display" deviation="0.0005"
+ name="display-cnc-gvariable-9016"
+ tooltip="Encoder error value for axis X"
+ bgColor="##b-display" displayWidth="120" fontStyle="bold"></gitem>
+<gitem where="x-coordinates" position="74;100" width="120" height="30"
+ displayAlignment="left;vcenter"
+ fgColor="##f-machinepos" format="%8.3f" fontFamily="Open Sans"
+ fontSize="16" type="display" deviation="0.0005"
+ name="display-cnc-gvariable-9017"
+ tooltip="Encoder error value for axis Y"
+ bgColor="##b-display" displayWidth="120" fontStyle="bold"></gitem>
+<gitem where="x-coordinates" position="74;160" width="120" height="30"
+ displayAlignment="left;vcenter"
+ fgColor="##f-machinepos" format="%8.3f" fontFamily="Open Sans"
+ fontSize="16" type="display" deviation="0.0005"
+ name="display-cnc-gvariable-9018"
+ tooltip="Encoder error value for axis Z"
+ bgColor="##b-display" displayWidth="120" fontStyle="bold"></gitem>
+<gitem where="x-coordinates" position="74;200" width="120" height="30"
+ displayAlignment="left;vcenter"
+ fgColor="##f-machinepos" format="%8.3f" fontFamily="Open Sans"
+ fontSize="16" type="display" deviation="0.0005"
+ name="display-cnc-gvariable-9019"
+ tooltip="Encoder error value for axis A"
+ bgColor="##b-display" displayWidth="120" fontStyle="bold"></gitem> </code>
+In the current version, registers 9232, 9233, etc are used instead (you may need to edit your XML file if using an older version).
+. Display of the error graphs is done via editing the ''x-bottab-left-mill.xml'' file. In general, the ''myscope'' type is responsible for displaying oscillograms. For older profiles, find and correct the displaying 3 graphs with variables 9016, 9017, 9018 (for PID0, PID1, and PID2 errors)
+<code XML><gitem where="x-graph" position="10;10" width="880" height="380"
+ name="myscope1" type="myscope" yrange="-300;300" K="1"
+ source="cnc-gvariable-9016;cnc-gvariable-9017;cnc-gvariable-9018" sampling="50" /></code>
+{{:mycnc:linear-encoders-002.png}}
+.
+In order for registers 9016, etc to show an error, the PID must be enabled.
+This requires 2 steps -
+) Check the ''Enable'' setting in the PID settings pulse-dir closed-loop
+) Start the Servo-ON procedure by writing "1" to register 60000
+<code>gvarset (60000,1); // run Servo ON procedure </code>
+For automatic servo on procedure, this line can be added to _HANDLER_INIT. For manual start, there is a Servo-ON button, which, in turn, starts the _HANDLER_SERVO_ON procedure. In it, in turn, is the necessary command to write to the in the register (after any other required actions, for example, after sending the Servo-ON signals to drives, etc.)
+{{:mycnc:linear-encoders-003.png}}
+{{:mycnc:linear-encoders-004.png}}
+By means of a multiplier and a divider, the "software" resolution of the linear encoder must be brought to be in the "pulse-per-mm" units. In the "Linear Encoder Dimension" field, you must specify the resolution taking into account these factors and divisors, after which the controller will then operate with this program value.
+If the PIDs are turned off and not used, but you simply need to have a position indication, then a different set of registers is used for display, and the multiplier and divider fields are not used. If that is the case, then the real resolution of the linear encoder is indicated in the "Linear Encoder Dimension".
+At this point, it is necessary to input the correct coefficient "K" for displaying graphs and error values.