Each Offset Mirror System is accessible from the LFE/KFE home screens in the "Mirrors" row.
One should request positions to the "<axis> user setpoint" field, where <axis> is of the following: "y up", "y dwn", "x up", "x dwn", "pitch", or "bender"
Detailed Python Documentation: https://pcdshub.github.io/pcdsdevices/generated/generated/pcdsdevices.mirror.XOffsetMirror.htm
happi entries : found by searching for device name (same as system name but all lower case):
$ happi search name=mr1l0_homs$ happi search name=mr2l0_homs$ happi search name=mr1k4_soms
Essential PVs
Each device has a prefix including the device name and fungible term. Fungible terms can be found here: Device Names
Ex: MR1L0:HOMS, MR2L0:HOMS, MR1K4:SOMS
Axis Setpoint/Readback Suffixes
| Suffix | Description |
|---|---|
| :MMS:YUP (:MMS:YLEFT for MR1K2) | Yup (Yleft for MR1K2) User Setpoint |
| :MMS:YUP.RBV (:MMS:YLEFT.RBV for MR1K2) | Yup (Yleft for MR1K2) User Readback |
| :MMS:YDWN (:MMS:YRIGHT for MR1K2) | Ydwn (Yright for MR1K2) User Setpoint |
| :MMS:YDWN.RBV (:MMS:YRIGHT.RBV for MR1K2) | Ydwn (Yright for MR1K2) User Readback |
| :MMS:XUP | Xup User Setpoint |
| :MMS:XUP.RBV | Xup User Readback |
| :MMS:XDWN | Xdwn User Setpoint |
| :MMS:XDWN.RBV | Xdwn User Readback |
| :MMS:PITCH | Pitch User Setpoint |
| :MMS:PITCH.RBV | Pitch User Readback |
| :MMS:BENDER | Bender User Setpoint |
| :MMS:BENDER.RBV | Bender User Readback |
- i.e a complete PV for MR2L0's pitch readback would be:
MR2L0:HOMS:MMS:PITCH.RBV- Note: one can specify the precision returned by
cagetusing-f <N>, where<N>is the desired number of decimal places, i.e$ caget -f 5 MR2L0:HOMS:MMS:PITCH.RBV
- Note: one can specify the precision returned by
Encoder Readback Suffixes
The PLC pushes encoder arrays of 1000 elements sampled at 1 kHz for each upstream (master) axis' actual position readback to epics. The mean, standard deviation, rms deviation from the setpoint, and the entire array itself are accessible from the following PVs:
| Suffix | Description |
|---|---|
| :ENC:Y:ACTPOSARRAY_RBV | Array of 1000 encoder readback values for Yup sampled at 1 kHz |
| :ENC:Y:SETPOSARRAY_RBV | Array of 1000 axis set point values for Yup sampled at 1 kHz |
| :ENC:Y:MEAN_RBV | Mean of Yup encoder actual position array |
| :ENC:Y:STDEV_RBV | Standard deviation of Yup encoder actual position array |
| :ENC:Y:RMS_RBV | RMS deviation from setpoint for Yup encoder actual position array |
| :ENC:X:ACTPOSARRAY_RBV | Array of 1000 encoder readback values for Xup sampled at 1 kHz |
| :ENC:X:SETPOSARRAY_RBV | Array of 1000 axis set point values for Xup sampled at 1 kHz |
| :ENC:X:MEAN_RBV | Mean of Xup encoder actual position array |
| :ENC:X:STDEV_RBV | Standard deviation of Xup encoder actual position array |
| :ENC:X:RMS_RBV | RMS deviation from setpoint for Xup encoder actual position array |
| :ENC:PITCH:ACTPOSARRAY_RBV | Array of 1000 encoder readback values for Pitch sampled at 1 kHz |
| :ENC:PITCH:SETPOSARRAY_RBV | Array of 1000 axis set point values for Pitch sampled at 1 kHz |
| :ENC:PITCH:MEAN_RBV | Mean of Pitch encoder actual position array |
| :ENC:PITCH:STDEV_RBV | Standard deviation of Pitch encoder actual position array |
| :ENC:PITCH:RMS_RBV | RMS deviation from setpoint for Pitch encoder actual position array |
| :ENC:BENDER:ACTPOSARRAY_RBV | Array of 1000 encoder readback values for Bender sampled at 1 kHz |
| :ENC:BENDER:SETPOSARRAY_RBV | Array of 1000 axis set point values for Bender sampled at 1 kHz |
| :ENC:BENDER:MEAN_RBV | Mean of Bender encoder actual position array |
| :ENC:BENDER:STDEV_RBV | Standard deviation of Bender encoder actual position array |
| :ENC:BENDER:RMS_RBV | RMS deviation from setpoint for Pitch encoder actual position array |
Raw Encoder Counts and Reference Values
| Suffix | Description |
|---|---|
| :ENC:YUP:CNT_RBV | Yup encoder raw count (nm) |
| :ENC:YUP:REF_RBV | Yup encoder reference count (nm) |
| :ENC:YDWN:CNT_RBV | Ydwn encoder raw count (nm) |
| :ENC:YDWN:REF_RBV | Ydwn encoder reference count (nm) |
| :ENC:XUP:CNT_RBV | Xup encoder raw count (nm) |
| :ENC:XUP:REF_RBV | Xup encoder reference count (nm) |
| :ENC:XDWN:CNT_RBV | Xdwn encoder raw count (nm) |
| :ENC:XDWN:REF_RBV | Xdwn encoder reference count (nm) |
| :ENC:PITCH:CNT_RBV | Pitch encoder raw count (nm) |
| :ENC:PITCH:REF_RBV | Pitch encoder reference count (nm) |
Encoder Readback Data Storage Script
- Script to read encoder array PVs and write to .csv file with timestamps.
- See GitHub README for detailed usage: https://github.com/jsheppard95/encoder_data_storage
Other Useful Suffixes For Motor Records
- Any motor PV can include the following suffix for additional parameters:
| PV Suffix | Function |
|---|---|
| .VELO | Setpoint Velocity |
| .RDBD | Epics deadband |
| :PLC:bReset | Reset an axis error in Epics |
| :PLC:bPowerSelf_RBV | Motor power PV, should be TRUE in normal operation |
XRT Mirror PVs
The following are showing for XRT-M1. Substitute M1H for M2H and M3H as needed.
Position Set Point and Read Back
| PV | Function |
|---|---|
| XRT:M1H:Y:P:VAL | Y master axis set point position |
| XRT:M1H:Y:S:VAL | Y slave axis set point position |
| XRT:M1H:X:P:VAL | X master axis set point position |
| XRT:M1H:X:S:VAL | X slave axis set point position |
| MIRR:XRT:M1H:VAL | Pitch axis set point position |
| XRT:M1H:Y:P:RBV | Y master axis read back position |
| XRT:M1H:Y:S:RBV | Y slave axis read back position |
| XRT:M1H:X:P:RBV | X master axis read back position |
| XRT:M1H:X:S:RBV | X slave axis read back position |
| MIRR:XRT:M1H:RBV | Pitch axis read back position |
Pitch Deadbands
These PVs control the handoff between the pitch stepper and piezo motion. For the stepper, this indicates the distance from the set point at which point the stepper will disable and allow the piezo to finish the move. For the piezo, this indicates the distance from the set point at which point the move is determined to be "complete".
| PV | Function | Run 18 Value (urad) |
|---|---|---|
| MIRR:XRT:M1H:DBD | Stepper motor deadband | 2 |
| PIEZO:XRT:M1H:DBD | Piezo motor deadband | 1 |
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