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The MTRotator CSC controls the camera rotator on the Simonyi Survey Telescope.

User Guide

Start the MTRotator CSC

Start the MTRotator CSC as follows:


Enable the MTRotator CSC

The enable sequence is slightly unusual because the MTRotator and MTMount are closely linked. The MTRotator will go to fault if it is enabled and not receiving camera cable wrap telemetry from MTMount, or if it is connected, but the angle difference gets too large. But MTMount will stop following the rotator if it does not get rotation telemetry from MTRotator.

The recommended sequence is as follows:

  • Send the MTRotator to disabled state. If this fails, fix the problem before continuing.

  • Send the MTMount to enabled state. This will give it a chance to center the camera cable wrap on the rotator.

  • Enable the MTRotator.

To Recover from Fault State

  • To recover from the FAULT state (after fixing whatever is wrong): send the CSC to standby and then enable it. In detail: issue the standby, start, and enable commands.


The CSC includes a simulation mode. To run using CSC’s internal simulator:

run_mtrotator --simulate

Enable With the EUI

The control mode must be DDS in order for the CSC to control the low-level controller. If the control mode is GUI, use the EUI’s Parameters panel to change it to DDS.


  • The EUI shows the control mode on the main panel, but that display is read-only. You must use the Parameters panel to change the control mode.

  • If you issue any hexapod command in the EUI, control mode will switch back to GUI. So if you want the CSC to retain control, please be careful what you touch when using the GUI.

Developer Guide

Version History