LASCO/EIT On-Board Observing Programs (LP)
An LP is software that has been designed to perform a particular task called
observation program. The various LPs together provide the functionality of the
OBE (observation Executive) which is the operating system of the LEB (LASCO/EIT
Electronics Box) main processor. An LP may be
to be performed at a particular time (delta from the current time) and to
when a certain condition is met. Together the scheduled LPs form the various
tasks that will be performed during the subsequent hours.
The following is a list of the currently defined LPs and a brief description
- Take Normal Image
- This observation program is used to take normal images, using shutters,
from C2,C3 and EIT. C1 images can be taken, but no commanding of the FP
- Take FP Scan Line
- This observation program is used to build a set of single Fabry-Perot
wavelength images to obtain a complete line profile scan.
- Wobble Inside FP Sequence
- Take an image sequence using the C1 in dynamic imaging mode. The M1
mirror is moved to the four corners of a square, 1/2 pixel on a side,
at each wavelength in a Fabry-Perot sequence.
- Wobble Outside FP Sequence
- Take an image sequence using the C1 in dynamic imaging mode. A full
Fabry-Perot sequence is taken at each position of the M1 mirror. The M1
mirror is moved to the four corners of a square, 1/2 pixel on a side.
- Take Polarization Sequence
- This observation program will take a sequence of images at a given
filter wheel position, but changing the polarizer (or sector) wheel
position for each image.
- Take inter-sum of images
- This observation program is used to take normal images, from C2,C3
and EIT. C1 may also be imaged, but no FP commands are sent. An
initial image is taken, and then subsequent images are added to or
differenced from the image prior to transmission to the ground. The
processing is determined by the contents of the image processing table.
- Take Sequence of Images
- This observation program is used to take a sequence of "normal" images
from C1, C2, C3 and EIT. The desired sequence is specified by the input
- Take Concurrent images
- This observation program will take simultaneous (concurrent) images
from one or more of the telescopes.
- Block Schedule
- This observation program use the preloaded schedule block to schedule
LPs. The schedule block can contain up to 500 schedule commands.
The schedule block command consists of a schedule type and time
block and a set of LP parameters which are uploaded for later use.
- Take Dark Current Image
- This Observation Program is used to take dark images, from C1, C2, C3
and EIT. The filter, polarizer and shutter mechanisms are not moved.
- Take calibration lamp image
- This observation program is used to take internal calibration lamp
images, possibly using shutters, from C1, C2, C3 and EIT.
- Perform FP and Camera
- This observation program will perform various calibration functions
of the FP which require a close coordination between the camera and
the FP. These FP functions are scan central aperture, measure finesse,
- Take Pseudo-continuous Images
- This observation program takes images using the pseudo-continuous mode,
in which the image is read out while the shutter is open. Thus each
pixel in a column on the CCD is exposed to the same scene. It is
primarily used for CCD calibration.
- Perform FP Check and Correct
- This observation program is used to command the Fabry-Perot electronics to
perform a check and correct algorithm of the FP to calibrate the correspondance
between plate separation and wavelength.
- Status Request Peripherals
- This LP is used to explicitly solicit status from each peripheral
(four cameras and the Fabry-Perot interferometer). Status will be
obtained for the telescope that is being commanded by an imaging LP,
and this LP will be automatically performed whenever the LEB is not
performing some other LP.
- Take M1 Measurements
- Command the C1 M1 Measurement unit to turn on and return the values of
the LVDTs and the M1 temperatures.
- Dump memory
- This observation program will send a memory dump from any of the LEB
processors (OBE, TCE, ICE, PCE) down to the ground via the science
- Open/Close M1 Lid or Move
- This observation program is scheduled to either move the M1 DACS to a
commanded position or to open / close the M1 lid.
- Process ground to
- This observation program is used by the ground operator to explicitly
command the camera or Fabry-Perot. Commanding of the camera and
FP are normally done by the imaging LP. This LP is only used to
configure a camera or FP into a mode that is not normally needed.
- Process loading of peripherals
- This observation program is used to load software into the five
peripherals (cameras and FP). This is not normally used directly by
Parameter Table LPs
- Load Default Camera Parameters
- This observation program enables one of the three parameter tables
(primary, alternate, or calibration) for a camera to be modified at a
specific time in the schedule.
- Schedule Mechanism Command
- This observation program will command a mechanism motion at the
scheduled time. Filter wheel, polarizer wheel, sector wheel and
shutter motions are commanded from within an observation program,
but other mechanisms (door, focus, etc) are not.
Last revised 16 Jul 1996 - DW