PT Telescope Control

Overall layout

The PT telescope control GUI looks like this:

The PT telescope control GUI is divided into 3 sections:

1. A row of buttons for controlling communications with and sending commands to TCS, the software which controls the PT (analogous to the TCC).
2. Two columns of status data.
3. A row of buttons for positioning the telescope.

Control buttons

The row of buttons along the top of the window perform a variety of tasks:

Refresh

The refresh button causes MOP to request a status update from TCS. This updates two MOP internal arrays which hold status information received from TCS: dfmData and dfmStat. While some MOP commands force these arrays to be updated, they are not always kept in perfect sync with their true (TCS) values. The refresh button can be used to force an update.

This button is the GUI equivalent of:

mt> dfmCoords -informGUI

mt> dfmStat -informGUI

Init

This button initializes TCS by setting the time and date to that from the sdssmth clock, turning on tracking (if the tracking switch in the dome is turned on), and updating the MOP array dfmData.

This button is the GUI equivalent of:

mt> initializeTelescope

Release

This button closes the connection to TCS and shuts down the telescope GUI. Be careful with this; if the connection to TCS is lost, many other routines which require the connection will fail.

This button is the GUI equivalent of:

mt> dfmNodeClose

mt> destroy $mopGUI(telescopeGUI)

Point to Zenith

Provided the switches in the dome are set properly for movement, this button will turn off the tracking and point the telescope at zenith. This button is not a replacement for the normal closing procedure.

This button is the GUI equivalent of:

mt> dfmParkAtZenith

Point to Dome Screen

Provided the switches in the dome are set properly for movement, this button will turn off the tracking and point the telescope at the dome screen. In general, pointing the telescope to the dome using MOP is not the preferred procedure. Using the TCS directly (from the dome) is. (If the dome screen is moved, or the coordinates of the dome screen are adjusted for some other reason, the values in TCS are more likely to be appropriately maintained.)

This button is the GUI equivalent of:

mt> pointToDomeScreen

Quit

This button exits the PT telescope GUI. This method of closing the window should only be used when the PT telescope GUI is run as a stand-alone, as opposed to being started with the other MOP GUI windows. In general, shutdownGUI should be used instead.

Status array display

The contents of the data array MOP uses to keep track of data from the TCS, dfmData and dfmStat, are displayed in the right and left columns of values, respectively. Detail on the meaning of each element can be found in the TCS manual, which belongs in the tool cabinet in the PT dome.

Most values displayed here can also be seen on the TCS display screen.

Two elements (those where the value boxes displayed with "sunken relief") of the dfmData array can be edited by changing the value directly and hitting return in the entry box. These are:

epoch

The display epoch used by TCS can be edited here.

If $epoch is the desired epoch, editing the value here and hitting return is the GUI equivalent of:

mt> dispEpoch $epoch

mt> dfmCoords -informGUI

mt> dfmStat -informGUI

focus

The telescope focus position can be changed by editing this box.

If $focus is the desired focus position, editing the value here and hitting return is the GUI equivalent of:

mt> focusPT $focus

mt> dfmCoords -informGUI

mt> dfmStat -informGUI

If this method is used to change these parameters, remember that you need to hit return in the entry box for the change to take effect.

Other pointing buttons

The three buttons on the lower left of the window can be used for other pointing tasks.

Set next object

This button brings up a dialog asking for coordinates. After coordinates are entered using this dialog, MOP loads them into TCS. You should see the new coordinates appear in the TCS display, together with the airmass and hour angle of those coordinates. To actually slew to these coordinate, use the "Slew to next object" button.

This is the GUI equivalent of the command

mt> nextObject $RAhours $RAminutes $RAseconds $DecDegrees $DecMinutes $DecSeconds $epoch

Slew to next object

This button asks the TCS to actually slew the PT to the set of coordinates previously loaded into TCS using the "Set next object" button, above, the nextObject command from the command line, or directly at the TCS.

This is the GUI equivalent of the command

mt> dfmSlew

Offset telescope pointing

This button is used to offset the telescope from its current position. After hitting the button, the user must enter the desired RA and Dec offsets, in arcseconds. MOP will then perform the requested offset.

This is the GUI equivalent of the command

mt> doOffset $raOffset $decOffset

where $raOffset and $decOffset are the offsets in RA and Dec, respectively, in arcseconds.

Last modified 6/21/2001 by E. H. Neilsen, Jr.