Appendix B - Complete command list¶
- COMMAND TEMPORISATION All commands can be temporised (i.e.
- associated to a starting time) adding a proper suffix. There are two possibilities:
- absolute temporisation (the operation will be performed at the
@DOY-HH:MM:SS, where DOY is the Day-Of-Year (1-366) and HH:MM:SS is the UT time;
- iterative temporisation (the operation is performed now, then
periodically according to the indicated time interval):
@!DAYS-HH:MM:SS, where DAYS is the number of days and HH:MM:SS is hours, minutes, seconds.
Commands (temporised or not) can be used also in the init/pre-scan/post-scan procedures inside schedules. Observers are in charge of considering if and when the use of a certain command makes sense in their schedule, according to their specific needs and goals: this is something that no schedule parser can check!
Here follow all the commands exploitable in DISCOS:
sends the antenna to stow position
resets the alarm conditions
KKG, …) unstows the antenna, sets it to tracking mode and configures the pointing model according to the specified receiver. It does NOT perform the receiver and backend setup
stops the antenna. Activities can start again only commanding a mode change as
antennaTrack(which does not affect the overall setup) or a new setup
sets the antenna to PROGRAMTRACK mode. It does not change the pointing model or any receiver setup
PF) performs the setup of the active surface
sets the Az-El offsets (degrees). They are intended “on sky”, i.e. it is the actual offset run on the sky at the source Elevation.
switches the calibration mark on
switches the calibration mark off
selects the backend; string can be
selects the backend; string can be
zeroes the subreflector system-defined offsets (e.g. the ones resulting from a focus scan)
performs a cross-scan on the previously selected target (indicated using the
siderealcommands), along the scanFrame (
GAL), spanning span degrees in duration seconds
reads out the present dewar position angle (degrees)
[conf] can have one of the following values:
sets the dewar angle (degrees). Positive angles = CW. According to the derotator configuration in use, the command has different meanings. It is illegal for the
computes the beamsize, taking into account the present receiver and backend configurations relative to section sect
deletes the N-th element in the queue of temporised commands
deletes all the queue of the temporised commands
performs a focus scan over the tracked source, span is in mm along the z-axis, duration is expressed in
It collects all the required data from the antenna, the back-end and the front-end, plus the information provided by the user (see the
restFrequencycommands), then it tunes the telescope devices in order to centre the line(s) in each section bandwidth. The command lets the user select which device [dev] is asked to perform the tuning:
- LO: only the front-end local oscillator is moved
- ALL: the back-end performa a sub-tuning in the various sections
reads the attenuation values (dB) currently configured for the active sections, and lists them according to increasing section number
reads the signal intensity (raw counts) for the active sections, and lists them according to increasing section number
slews the antenna to an offset position, wrt a previously commanded target, along the longitude axis of the indicated coordinate frame (
GAL). The user provides the offset value expressed in beamsizes. If the frame is HOR and target lies beyond the Elevation cutoff limits, the offset is applied in Elevation.
sends the antenna, while in TRACKING mode, to the specified Az-El position.
Arguments are always rounded in the range 0-360 and 0-90 for azimuth and elevation respectively (in any case the ranges are limited to mechanical contraints). The jolly character is valid and is considered as: keep the present value. The differences from the
- once the antenna reaches the destination, the system will acknowledge the “on source” status;
- the pointing corrections (pointing model and refraction) are applied. In case they are not required they must be turned off explicitly.
completes the current scan and then stops the schedule
XK77, …) configures the backend using the default parameters relative to the selected receiver. It does not act on the receiver, pointing model or antenna mount mode.
sets the backend integration time (ms)
defines a custom name for the logfile (do not specify the extension)
sets the Galactic b-l offsets (degrees). They are intended “on sky”, i.e. it is the actual offset run on the sky at the source latitude.
points the antenna to the present coordinates of the center of the Moon
sends the antenna, if in PRESET mode, to the specified Az-El position, without applying any pointing correction. This is useful when needing to point to a position next to the zenith. Beware: the antenna will reach the destination but no “on source” flag will be raised.
lets the system know which project is observing (the code/name must correspond to the one provided by the TAC). This code/name is then considered as default when launching schedules: the system will search for them in a folder named “project/schedules”. This code/name also forms part of the output FITS filename. Notice that the PROJECT keyword indicated inside the schedule, which is then written in the “Project Name” keyword in the FITS main header, is a free string and might differ from the project official name.
sets the RA-Dec offsets (degrees). They are intended “on sky”, i.e. it is the actual offset run on the sky at the source Declination.
[vrad] (radial velocity) is in km/sec if vdef is not Z
[vref] (reference frame) can be one of the following:
- BARY: Solar System BARYCENTRE
- LSRK: Kinematic Local Standard of Rest
- LSRD: Dynamical Local Standard of Rest
- LGRP: Local Group
- GALCEN: Galactic Centre
- TOPOCEN: TOPOCENTRIC (observer’s frame)
[vdef] (velocity definition) can either be:
- RD: Radio Definition
- OP: Optical Definition
- Z: stands for Redshift
The specified velocity parameters are valid until a new target is commanded. The
radialVelocitycommand overrides any other velocity value that might have been differently expressed
configures the working mode of the receiver, according to its peculiar characteristics
> receiversSetup=[code] (CCB, KKG, etc...)
KKG, …) configures the receiver using the default parameters. It does not act on the backend, pointing model or antenna mount mode
[freq] is given in MHz and is a multiple argument: it can list a different value for each of the N sections - as long as XARCOS is the backend in use (not all the backends allow this sub-tuning). Specifying a single value assigns the rest frequency to all the sections. The specified values will hold until different ones are commanded, or until a new general setup command is entered.
stows the minor servo system
KKG, …) configures the minor servo system only
sets to att (dB) the attenuator of section sect
Local Oscillator frequency, in MHz (one per IF, separated by “;”, usually the values are identical) This LO frequency corresponds to: SkyFreq(@band start) – 100 MHz when using the TPB
configures the backend section sect.
> setServoASConfiguration=ON (or OFF)
chooses the subreflector pointing model according to the AS being enabled (ON) or disabled (OFF)
sets the subreflector to tracking mode, with OFF tracking is disabled
(see details in Antenna operations)
> setupCCB (setupLLP, setupKKG, etc…)
unstows the antenna, sets it to tracking mode, selects the pointing model, and configures the receiver and the backend using default parameters. In practice, it is a shortcut corresponding to this sequence:
> antennaSetup=[code] > receiversSetup=[receiverCode] > initialize=[receiverCode] > device=0 > calOff
points to the supplied RA-Dec position and temporarily assigns the sourcename label to it. Epoch can be
-1, the last one meaning that the provided coordinates are precessed to the observing epoch. The sector keyword forces the cable wrap sector, if needed: its value can be
NEUTRAL. The last option means the system will automatically choose the optimal alternative.
performs an OTF acquisition at the current azimuth position, spanning in elevation from El1 to El2 (both expressed in degrees, with ‘d’ suffix), in duration time, expressed as hh:mm:ss. A recorder must have previously been enabled in order to save the data, and a reference sky position must have been specified via a
runs schedule schedulename.scd (project is the ID of the observing project, it is optional if it has already been input through the
projectCodecommand), reading it from line N
immediately stops the running schedule, truncating the acquisition
stows the antenna and parks both the AS and the MS
lists all the active temporised commands
points the antenna, in sidereal tracking, to the specified source, which must be present in the local catalogue
measures the system temperature (K) in the position the antenna is pointing to. It returns a list of values, one for each section in use. Intermediate steps and calculations are stored in the active logfile
sets a delay (in seconds) which is applied before the system reads/executes the next command
activates the winking (i.e. fast switching) calibration mark for the TPB. The duty cycle is specified by the integer parameter, which indicates the number of off-cal samples after which an on-cal sample is acquired. To switch the mark off, simply command a zero-sample period. This must always be done when the winking mark is not needed anymore.
> winkingMark=3activates the mark so that it is ON for one sample every 3 samples OFF.
> winkingMark=0switches the mark off
returns the current weather parameters: ground temperature (°C), relative humidity (%), atmospheric pressure (hPa), wind speed (km/h).