PCA Software Provided To The SOF
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The Rossi X-ray Timing Explorer (RXTE) Science Operations Center (SOC) 
consists of:
 
(1) The Guest Observer Facility (GOF). This supports all post observation
    activities for guest observers (GO's) and is their main point of contact
    with the RXTE support structure at the Goddard Space Flight Center (GSFC). 

(2) The Science Operation Facility (SOF). This supports the real time 
    operations of the experiments on RXTE. It also provides a service to GO's
    who wish to be present in real time to experience their observation or
    interactively evaluate and change it. The SOF also supports remote
    monitoring of real time data at a GO's home institution. This service has
    to be arranged in advance with the SOF and remote display is only
    permitted for the specific duration of the observation.

The SOF software system was created in C++ and is quite distinct from the 
GOF which operates largely in a FORTRAN FTOOLS and FITS environment. The SOF
software effort was widely distributed and the Instrument Teams (IT's) were
contracted to deliver a considerable amount of supporting code for their
hardware experiment. The PCA C++ code was developed using Object Centre from
CenterLine Software Inc. and the GUI used was TAE+ which is a commercially
available NASA product. All documentation associated with the SOF was produced
using FrameMaker from Frame Technology Corporation. 

A detailed Build delivery schedule was maintained during the development period
which ran from early 1993 until a pre-launch freeze in mid 1995. These Builds
spanned numbers zero to four with a final revision Build 4.5.3 being used for
the In Orbit Checkout (IOC) period from 1-30 January 1996. Since the software
freeze bug fixes, enhancements and new features have all been performed under 
a Configuration Control Board (CCB) which regularly meets to review submissions
and track approved changes.

The documents associated with the PCA software are listed below. Postscript
versions of each are available. The simulator document is included for
completeness since it played a vital part in proving the end to end quality of
the PCA Housekeeping data. Simulated data packets can easily be compared to the
final contents of the PCA Housekeeping FITS files to form a canonical test for
future SOF Builds. 

The PCA detectors output all their events to an Experiment Data System (EDS)
supplied to RXTE by the Massachussetts Institute of Technology (MIT). Details 
on the EDS itself can be found in the MIT EDS WWW pages. Once the EDS science
data arrives in the SOF it again becomes of prime concern to the PCA team who
provided the real time science monitoring software display tools.

Guest observers will most likely only be interested in the Science Monitoring
Overview, Users Guide and poster paper documents.