Writing Scripts
The Gemini user interface software provides a script or macro capability that allows the user to put together any number of commands to be executed sequentially as a group, in much the same way as a UNIX shell-script or a VMS command procedure. This feature is especially useful for carrying out a repetitive observing/operation sequence, such as making a mosaic and doing repetitive engineering tests. The script tool is provided in both the menu interface mode and the command line mode.
List of Script Commands
Create a Script File
Execute a Script File
Example Script File
Script writing tool Currently does basic dithering scripts.
| System Commands | |
| BEEP 0-10000 | generate beeps for 0-10000 milliseconds |
| CONFIRM str | print confirmation information str |
| DISKSPACE | check free disk space |
| DO 1-1000 | iteration operator for script file |
| ENDDO | iteration operator for script file |
| ECHO str | echo string str |
| PAUSE num str | pause system num sec (0=indefinite) and print str |
| Observing Setup Commands | |
| COADDA 1-9999 | set number of co-adds for channel A |
| COADDB 1-9999 | set number of co-adds for channel B |
| FILENUMA 1-9999 | change image file running number for channel A |
| FILENUMB 1-9999 | change image file running number for channel B |
| FILTERA filtername | change filter for channel A |
| FILTERB filtername | change filter for channel B |
| ITIMEA 0.000-999 | set itime (seconds) for channel A |
| ITIMEB 0.000-999 | set itime (seconds) for channel B |
| MULTIA 2-9999 | set number of samples for multi-sampling mode, channel A |
| MULTIB 2-9999 | set number of samples for multi-sampling mode, channel B |
| OBJECT str | set current object name |
| SAMPMODEA 1-6 | set sampling mode for channel A (1=single, 2=CDS, etc) |
| SAMPMODEB 1-6 | set sampling mode for channel B (1=single, 2=CDS, etc) |
| OBSMODE Imaging|Polar|SpPolar | change observing mode |
| STPAP Open|Spot|Sinslit|Dblslit | change aperture wheel position |
| SPTAUX Open|Calcite|Polariz | change auxiliary wheel position |
| STPDIC K@LW|K@SW | change dichroic slide position |
| STPWPS Out|In | change wave plate (IO) position |
| STPWPR 0|22.5|45|67.5 | change wave plate (rotation) position |
| STP_INIT Ap|Aux|SWF|LWF|Dic|Pol|WPS|WPR | initialize stepper motor |
| Observing Commands | |
| Go A|B|2 | start integration for channel A, B, or both |
| MOVIE A|B|2 | start movie mode for channel A, B, or both |
| TEST A|B|2 | take test frame(s) for channel A, B, or both |
| TV Display Commands | |
| TV A|B|2|filename | display channel A/B frame or FITS file filename |
| TV_DISP On|Off | turn on/off TV auto-display |
| TV_GAINA 0.001-1000 | set TV display gain for channel A |
| TV_GAINB 0.001-1000 | set TV display gain for channel B |
| TV_OFFSETA +/-32767 | set TV display offset for channel A |
| TV_OFFSETB +/-32767 | set TV display offset for channel B |
| Math & File I/O Commands | |
| IMDIFF A|B|2 | calculate image difference and display |
| IMSTATS A|B|file | calculate statistics for channel A or B frame or file |
| SAVE A|B|2 | save test frame from channel A or B or both |
| WDISK A|B | write channel A or B frame to disk in FITS |
| Telescope Control Commands | |
| TELMOVE x y | move telescope by x arcsec in RA and y arcsec in DEC |
| TELPOSN | read current telescope position (RA, DEC, HA) |
| AUTRETSET p x y | set autoguider reticle positions p=0 for guide reticle, p=1 for background reticle, x and y are the pixel positions of the reticle |
| AUTRETGET | read current autoguider guide and background reticle positions |
A few of the commands in the list are specifically designed for the script tool, such as BEEP, CONFIRM, ECHO, and PAUSE and the iteration operators DO and ENDDO.
Create a Script File
A script file is created or edited using the DOS screen editor. The
DOS text editor can be invoked from inside the Gemini user interface
program. In the menu mode, select Edit Script under the root menu item
Option. In the command line mode, escape to DOS and run the editor
directly. Script files are placed in the directory C:\GEMINI\SCRIPT
and have the file name extension .SCR. When editing a script file in
the menu mode, simply give the name of the script and the Gemini
program will add the directory path and extension to it.
Each command must have one line in a script file, but it can start
from any position in the line. Blank lines are allowed and a comment
line starts with #. The following is an example.
The script tool provides a syntax check feature which checks the
validity of a command and the validity and value range of its
parameter. For example, a script with the following two lines
To run the syntax check in the menu mode, select Check Script in the
Option item. In the command line, type CHKSCRIPT {filename}.
Execute a Script File
The Gemini program always makes a syntax check first when running a
script. If an error is found, the script execution is aborted before
any command is executed. To run a script, select Run Script in the
Option item (hot key CF3) in the menu mode or type SCRIPT
{filename} in the command line mode.
During the execution, the command currently being executed is
displayed in both interface modes. The next command will also be
displayed in the menu mode. For example, the script execution status
A script execution can be aborted by pressing the function key CTRL
F2. Note: the software will say press
CTRL F3 to abort the script - this is incorrect. CTRL F2
is the abort command. The execution stops only after the current
command execution is finished. Therefore, to abort and active command
in a script such as an integration immediately, press CTRL F2
first and then use the normal abort command.
IMPORTANT NOTES: If you are in the TV mode when a command execution is
finished, you must come back to the text mode in order for the next
command in the script to get started. Also, do not switch between the
menu mode and the command line mode or escape to DOS during a script
execution or the execution status display will get messed up.
Example Script File
# A test script file
# set parameters
ITIMEA 10
COADDA 3
# integrate
DO 3
GO A
ENDDO
Like in the command line mode, if a command parameter is not supplied
in a script file, the program will prompt for the parameter during the
execution.
ITIME 10
COADDA 0
will yield the following error messages when running a syntax check:
CL Error: invalid command - line 1 > ITIME 10
No syntax error is generated if a command parameter is not supplied in
a script. The program will not make a syntax check when the parameter
is entered during the execution.
CL Error: parameter value out of range - line 2 > COADDA 0
Script syntax check: 2 error(s) found
3:7 > GO A
4:7 > FILTERA H
shows that the script file has a total of 7 command lines and the
command being executed is the 3rd command line GO A; the next command
to be executed is FILTERA H.
# script to make a 1x9 mosaic
ECHO script to make a 1x9 mosaic
# set observing mode
OBSMODE imaging
# turn on tv display
TV_DISP on
# set observing parameters
OBJECT
SAMPMODEA 2
SAMPMODEB 2
FILTERA j
FILTERB kp
ITIMEA 30
ITIMEB 6
COADDA 2
COADDB 10
# confirm setup; Y to continue and N to quit
CONFIRM Is the setup correct?
# start 1st integration
GO 2
# loop 8 times
DO 8
# pause to turn off guider
PAUSE 0 Turn off guider
# offset 160 arcsec north
TELMOVE 0 160
# pause to find guide star
PAUSE 0 Find guide star
# integrate
GO 2
ENDDO
# beep 3 sec to wake up
BEEP 3000
Last modified: Thu Feb 15 15:49:05 PST 2007
by Elinor Gates