PC Move Program for the Perkins (72"), Hall (42"), LONEOS, Planet Search (PSST), 31", 18" Astrograph, and Wallace Telescopes

Version 4.84


Program MOVE controls telescope and autoguider operations and also provides access to control and status information by other computers via an RS232 port. The software is written in Microsoft FORTRAN/ASSEMBLER and will run on any standard PC.

Table of Contents

General Concepts
Auto Coordinate Lock
Moving by Object Name
Power Up
Program Initialization
Move Display

Summary of Move Commands

Guider Documentation (72"/42" only)

Guide to Remote Commands

General Concepts

1) All entries may be given in upper or lower case. Backspace (delete) may be used to delete typed characters. CTRL-U may be used to delete an entire line. ESC can be used at any time to abort any command. The only exception to this rule is that the ESC abort is disabled in all maintenance commands (see below for list).

2) Some MOVE commands (and many guider commands) use the numeric keypad. In MOVE, the keyboard is set up such that the four arrow keys will give the same result as the numeric keypad keys which have arrows on them. That is, the numeric 8 key is identical to the up arrow key. However, the six other numeric keys which have secondary marks (eg, the keypad 9 key is marked Page Up) are not identical in function to the six corresponding keys on the keyboard. Thus keypad 9 is different from the Page Up key even though it is marked Page Up.

3) Page Up toggles between guider and the default telescope display screens if autoguider or video guiding is enabled. All guider commands consist of three letters beginning with a G. Autoguider stages and focus motions can be controlled by the number pad arrow keys.

4) Entry of coordinates: Almost any reasonable form of entry will be accepted. When entering coordinates, a comma or a blank may be used to separate the hours (or degrees), minutes, and seconds. Leading zeroes or zero terms may be omitted. Thus, 3,0,3.123; 03,00,03.123; 3,,3.123; or 3 0 3.123 will all be accepted correctly. The parser also has no difficulty with the -0 declination problem. For example, -,,.1 or -00,00,0.100 will be accepted correctly. The program also accepts fractional minutes. Thus, -01,10.123 or 10 20.1 are also valid inputs. Note that one may request that the display be in fractional minutes (see the FN command, below). If an error is detected in the input, the program will ask for the value to be re-entered. Some commands ask that a negative RA be entered to terminate a sequence. For those commands, entering a single minus sign is sufficient.

5) Entry of times: Times follow the same rules as coordinates.

6) Entry of dates. Dates are entered in the form of 09-OCT-91. The month is not case sensitive and the leading zero on single digit days is not required. Only a two digit year will be accepted. Note that years between 81 and 99 will be considered as 1981 to 1999 and years between 00 and 80 will be considered as 2000 to 2080.

7) RA and DEC display: Mean coordinates, the default display, are those which have been corrected to the coordinates which would be found in a star catalog. Mean telescope positions account for all the effects of aberration, nutation, refraction, and all mechanical problems associated with the telescope. Mean coordinates can be displayed as those of the equinox of date, or can be precessed to any desired date.

8) Equinoxes: The MOVE program supports separate display and input equinoxes. There are two possible display equinoxes - that of date and that of some other, alternate equinox (which can be provided by the user - it is 2000.0 at startup). Input equinoxes can come in many forms: coordinates are entered in the keyboard equinox, positions read from an observing list file can be of any equinox, positions read from the guider catalog are of equinox 2000.0, ephemerides can be any equinox. If a move is requested to a position which is not given in the current display equinox, the position is precessed to the current display equinox and both the initial coordinates (as obtained by the program from the user, a file, an ephemeris, or from a catalog) and the final, precessed coordinates (as will match with the display when the move is completed) are shown on the screen.

9) Limits: At the 72", 42", and LONEOS, there are two limit regions - slow slew and horizon, both reported on the screen. The slow slew region is entered first. The horizon limit is the final limit. If the telescope enters the slow slew region, a warning beep turns on and a message appears on the console. If you have slewed into the region, the telescope motion continues but at a slower speed (1200 arcsec/sec vs 4200 arcsec/sec normally). Tracking and or ephemeris rates stay on. You now have two minutes to hit the limit override button on the console. Once you do this, all behavior will be normal with the exception of the slower slew speed. If you do not hit the override button within the allotted time, the electronics will switch on all four paddle button directions (a message will appear on the screen about EW and NS conflicts). Also, the intermittent warning beep will become continuous. While in this state, you cannot use the paddle to move the telescope nor can you do computer-controlled moves. At this point, you must push the limit override to restore normal behavior. If you continue through the slow slew region, you will eventually reach the horizon limit. At this point, a message appears on the console, the continuous warning beep comes on, tracking and/or computer-controlled moves are disabled. At the horizon, you can only move the telescope with the paddle while simultaneously holding down the limit override switch. In addition, only paddle directions which will move the telescope away from the horizon are allowed. At the PSST and the 31" there is only a single hard limit switch in each of the four directions. If a limit is reached while manually moving the telescope, motion in that direction is stopped by the motor controller. If a limit is reached while moving the telescope under computer control, the move is aborted. Limits are reported on screen. At Wallace there is a hard limit switch in RA and a horizon limit sensor in Dec. The RA limit behaves like the PSST/31" limits. The horizon limit in Dec behaves like the horizon limit at the 72"/42"/LONEOS in that you must hold down the override button and only paddle directions which move the telescope away from the horizon are accepted.

10) Moving the telescope: The telescope can be moved by either keyboard commands or by the hand paddle. Any keyboard commanded move must be confirmed by the user before the telescope actually begins to move. The net distance for any move is always reported, and the user must give confirmation before the move will be attempted. Moves are aborted if a hard limit or horizon limit is sensed. The move is also aborted at all telescopes if the user presses any direction paddle button while the telescope is moving (N, S, E, or W; Focus In or Out) or if any key is typed on the keyboard. At the 72", any move over 15 degrees requires that the user go out on the observing floor and press the green delayed slew button before the telescope will move. This ensures that the observer will be watching any long move. If there is a problem with the move, the red button will abort the slew.

11) Any command which takes a single argument can be entered with the argument on the same line as the command, separated from it by a space (e.g. NE 1950.0). If the argument is omitted, the program will prompt for it.

12) Dome following is toggled on and off via the DM command. Dome following is not available at the PSST or Wallace telescopes. Dome following checks if the telescope is more than 0.8 of the distance to the position where the "Warning - Move Dome" message would come on. If that distance is exceeded, the program moves the dome to a position where tracking will carry the object to the center of the slit in 11 minutes at the 72", 42", 31" or Astrograph and the true center of the slit at LONEOS. Dome following is disabled whenever the dome position is not currently shown on the screen (in help (HP), for example) or when the telescope is being manually slewed. When the telescope is moved from point to point (via a CO or RF command, for example), the final azimuth of the telescope is computed and the dome is moved to a position to match the final position of the telescope. When the move completes, normal dome following is re-enabled. If the move is aborted, both the dome and telescope motion are stopped, Normal dome following will resume after the next commanded telescope move.

13) Focus Control: The focus is operated by a stepper motor and can be moved by either keyboard commands (FG/FR) or by the hand paddle (at slew, set, or guide rates). The position of the focus stepper motor is continuously displayed on the screen along with a mode letter (R or A). The "A" indicates that the focus position is an "absolute" position relative to a fixed zero point. The "R" indicates that the focus position is a "relative" position relative to an arbitrary user-selected zero point. Any location can be chosen as relative zero using the FZ command. Absolute zero is the center of the focus range and is reset using the FI command. Under most circumstances, the user should never need to issue an FI. The program keeps track of the focus absolute position, even while in relative mode and you may swich between the two modes using the FT command. A commanded focus move (see FR and FG) is aborted if a character is typed or if the paddle is used. It is also aborted if the focus motor goes into the limit region. Limits are reported on the screen.

Auto Coordinate Lock

Unless manually turned off, the telescope automatically does coordinate lock at all times. Any commanded point-to-point move to a fixed target (CO, RF, PP, etc) will put the telescope into "sidereal rate" lock (the current state of the lock is always shown on the display). While in sidereal lock the current display coordinate is held fixed. Since the display coordinate is corrected for flexure, refraction, aberration, and nutation, holding the display coordinate fixed should also hold the star position fixed. Sidereal lock mode is also entered when sidereal tracking is turned on. An alternate lock mode is "track rate" lock. Executing an EG command (ephemeris go, see below) computes the current rates of the desired object from its ephemeris, moves to the ephemeris point and locks to the derived rate. Lock is turned off when sidereal track is turned off. The state of the lock may be manually set via the LM command (see below). If the paddle is used while locked (in sidereal or rate lock), the lock will be broken while the telescope is moved, and the same lock state resumed on completion of the move. Relative moves (via the RM command, remote commands, or the KM command) are treated the same way as paddle moves during lock. That is, the lock state at the start of the move is resumed at the completion of the move. During guiding with the Lowell Guider, the screen will show that lock is "Off - Guiding."  

Moving by Object Name

One may move the telescope by object name via the OG (Object Go) command. Catalog objects which are recognized are the Messier catalog (M n); the IC and NGC catalogs (IC n and NGC n); and the HR catalog (HR n; BS n and YBS n are also permitted). For all of these designations, n represents a number. The name is case insensitive and the space is optional (eg Hr1234, HR 1234, NgC1, ngc30, hgc 101 are all valid requests). The program also recognizes the Flamsteed and Bayer designations. The only constraint is that the last three characters of the request be a valid constellation abbreviation. Again, case is ignored. Thus, the following are all valid requests: a sco, asco,ASCO, Alpha Sco, 11 Sco, 11sco, 11SCO, etc. Lastly, the program recognizes a large number of items by their names: all the planets and the Moon, most of the common named stars (Vega, Deneb, Antares, etc) as well as over 300 named stellar and galactic objects (Ring Nebula, Hubble's Variable Nebula, etc). For named objects, the match is word-by-word. It is case insensitive and ignores special characters such as - or '. Thus a request for "h v n" will match both Hubble's Variable Nebula and Hind's Variable Nebula. If more than one object matches, the user is asked to select one. Note that one may search the list by asking for a single letter which will return everything which begins with that letter. As with other commands which take a single argument, one may give the command on one line (eg OG vega or OG 11sco). 


One may enter up to 999 ephemerides (either manually or via data files: see EE command). Each ephemeris can have as many points as needed to adequately define the ephemeris. While in track rate lock, the program recalculates the track rate after a time DT. where DT is the separation between the entered ephemeris points. Thus for objects whose rates are changing rapidly (Io, for example), one should provide an ephemeris with very short DT (5 minutes for Io).
When requesting an ephemeris (with the EG, EO, or SE commands), you may give the command with no argument (eg, EG) in which case the program will list all the available epherides and ask you to choose one. You can follow the command with an ephemeris number (eg, EG 34) which will request a move to the 34th ephemeris. Or, you can follow the command with an object's name (eg, EG Hale-Bopp). The comparison between the requested name and the name in the ephemeris file is made in upper case, with all blanks removed. If there are multiple matches found, they are reported, and the user is asked to choose one. Any part of the name can match so that EG Bopp will also find Hale-Bopp. If you are requesting a match with a name which is just a number, preceed the name with a # sign. For example, EG #5 will match with 5 Astraea.
If there is only one ephemeris currently entered EG, EO & SE default to EG 1, EO 1, & SE 1, respectively. 

Coordinate Classes and Saved Coordinates

There are three "classes" of coordinates: accurate, approximate and unknown. If the program considers the coordinates to be unknown, the RA/Dec are displayed in red on the screen. If the program considers the coordinates to be approximate, the RA/Dec are displayed in yellow. If the program considers the coordinates to be accurate, they are displayed in a normal white. Accurate coordinates are those defined by setting on a star and resetting the cooredinates. Thus one must do a UC (Update Coordinates) or an RE (REset coordinates) for the coordinates to be accurate. Setting the coordinates on the fiducial switches makes the coordinates approximate. In most cases the user will never see unknown coordinates as one has to bypass the normal startup procedures to get this class of coordinates. On normal exit of MOVE (via the QU (QUit) command) the current coordinates (and their class) are saved. When MOVE is next started the user is informed if the current coordinates are "likely invalid" (ie unknown), "based on fiducial switches" (ie approximate) or "valid" (ie accurate).

Power up

At the 72" the CPU resides in the computer room downstairs, the terminal and keybard are in the warm room. The computer is normally left on. At the 42", the CPU resides in the computer room; the terminal and keyboard are in the warm room. Turning on power to the telescope powers up the CPU; the terminal is turned on and off manually. At LONEOS, the computer resides in the computer room and is turned on/off separately. Startup at the Planet Search telescope is done remotely via the Sun computer. At the 31" the computer is in the cabinet in the lower level of the telescope and is left on all the time. The terminal is in the control building. The current arrangement at Wallace is unknown. When the computer boots in, the computer sets its default directory to C:\USER and begins MOVE. The initialization choices are prompted.  

Program initialization

Seven initialization procedures may be required on start up; guider, filter wheel, paddle interrrupt, dome, focus, and coordinate initialization. Starup at the 31" and PSST is automatic. MOVE fully stars without user intervention.

1) Guider initialization (42"/72"): The program asks if you will be using no guider (N), the Lowell guider (G), or another RS170 video source for guiding (V). See the Guider document for more details on guider initialization.

2) Filter wheel initialization(42"/72"/PSST): The filter wheel is moved to its index position and is left in filter position 1. If there is a problem with initialization or if the filter wheel is not connected, the filter wheel is designated as "unavailable" and commands to it are ignored.

3) Paddle interrupt initialization (LONEOS only): The user is asked to hit a paddle key two or three times and then type a carriage return to continue.

4) Dome initialization at telescopes with encoders (72", LONEOS, Astrograph): The program asks that the user move the dome to the right of the encoder sensor switch. At this point you can either move the dome and type carriage return or you may type escape to skip the dome initialization entirely. Follow the directions as to where to place the dome. If you skip this step, you can do it manually later via the ID (Dome Init) command. The program moves the dome to the left over the switch and then back to the right. If the switch is not seen, you may abort out of the routine by typing escape. This completes the dome initialization at LONEOS and the Astrograph. However, at the 72", if you intend to use dome following, you must also determine the dome coast distances. Again, at this point, you are asked to type carriage return to continue or escape to skip this step. If you continue, the program moves the telescope left or one second, then right; then left for two seconds, then right; etc. The total number of moves depends on the coast distance determined in the first phase of the initialization, but will be a maximum of five seconds left and then right. Each time the coast initialization is performed, a file containing the parameters is written to DOMPAR.DAT (in C:\MOVE). If dome initialization is skipped, this file is read back and used instead. Note that, if you skip the dome initialization, it may be done later via the ID command. Dome initialization at the 42" and 31" is somewhat simpler since these telescopes have a barcode reader. On startup the computer simply moves the telescope until it sees the first barcode. These two telescopes do not have an ID command as simply moving the dome is the initialization.

4) Focus initialization (at all telescopes) The program reads the saved position of the focus (and its mode -- A or R) and uses that as the startup value. If this file is missing (which should almost never happen), the program will do a a focus initialization (see the FI command).

6) Coordinate initialization

a) At the 72",42" or Wallace: If the program exited cleanly (via QU) the previous night, the coordinates of the telescope were saved and can be used to restart. The next question asks if you want to use the saved coordinates (by entering a carriage return); define the current position of the telescope as being at home (enter HO); set coordinates by the fiducials (enter IC); or enter the actual coordinates of the current location (enter RE). In most cases, just type carriage return which will bring up MOVE with the saved coordinates. If coordinates were not saved, you are given only the three remaining choices (IC, RE or HO). Note that entering IC is equivalent to doing an IC command (see below) and RE is similar to doing an RE command (see below). If IC is selected, the home (stow) position of the telescope is the correct location for executing this command.

b) At the 31": No user action is required. if the program exited cleanly (via QU) the previous night, the coordinates of the telescope were saved and are used to restart the telescope. If the saved coordinates is not found, the program assumes the telescope is at its home position (-5 deg Dec, 12m East hour angle) and starts the program at that position.

c) At LONEOS: Startup is the same as for the 42" or 72", but for this telescope, the fiducial switches are near HA=0/Dec=0 and the "stow" or home position is not. Should you choose the IC mode. the telescope must be moved so that it is positioned a degree or two south and east of the switches.

d) PSST: No user action is required. If the program exited cleanly (via QU) the previous night, the coordinates of the telescope were saved and are used to restart. If the saved coordinates file is not found the telescope slews south and east until it hits the limit switches. This telescope has a "home" switch built into the controller. The limit switches define which side of the switch it is on and it then initializes on the home switches.

e) Astrograph: No user action is required. If the program exited cleanly (via QU) the previous night, the coordinates of the telescope were saved and are used to restart. If the saved coordinates file is not found, the telescope starts up with undefined coordinates.

Move Display

Four information areas are supported on the display screen: telescope position and time, status information, data files, and command input. An alternate display, toggled by the page up key, provides guider information.

1) The first (topmost) area contains telescope position and time information:

a) The mean RA and DEC of the current display equinox and that equinox.
b) The hour angle of the mean RA and DEC
c)The sidereal time.
d) The UT or local time.
e) The JD (to four significant places after the decimal point).
f) The zenith distance of the mean RA and DEC.
g) The air mass.
h) The location of the dome relative to the telescope for the 72", 42", 31" and LONEOS telescopes. For the Planet Search telescope and Wallace, the telescope azimuth is shown.
i) The parallactic angle.
j) Moon or Sun data (see SM command). The moon display shows the distance of the Moon from the telescope, the phase of the Moon (percent illuminated), and the altitude of the Moon followed by an R if it is rising and an S if it is setting. The Sun display is the same except that the phase is blanked. When the Moon is requested, the entire display is blanked if the Moon is below -5 degrees altitude. When the Sun is requested, the full display is always shown.

2) The second area shows the telescope status, dome status, limits and other control status items. This part of the display contains:

a) The telescope status which indicates when the telescope is guiding, setting, or slewing, and the direction(s) as well as any motion conflicts.
b) Dome status indicates if dome following is on. If so, a message is given when the dome is moving. If dome following is off, then dome warning messages are given on this line if the dome is close to or actually occulting the telescope. The "close to" warning comes on when the telescope is within 2 degrees of the edge of the slit.
c) Status of the sidereal tracking (on/off; see TR).
d) Status of the coordinate lock (coordinate/tracking/off); the current rates in RA (s/hr) and DEC ("/hr); the number of the ephemeris from which the rates were derived.
e) If any limits are in effect (slow slew or horizon).
f) Telescope focus position.
g) The status of the remote port (on/off; see RT).
h) The position of the filter wheel (see GFW).
i) The name of the current object.
j) The status of the dome lights at the 31' and 72" (see LI).

3) The third area contains information about data files and star positions entered from the keyboard:

a) The keyboard coordinates equinox (default is current display equinox).
b) The name of any currently open star coordinates file. If no file is currently open, it is so indicated, and the next two items are not shown.
c) The number of entries in the file (if a file is open).
d) The ASCII descriptor for the file (if a file is open).

4) The fourth area of the display (on the bottom) scrolls and is the area in which the user provides command input.


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