CFHT Information Bulletin, number 38, First Semester 1998

TCS IV Status Report

Bill Cruise, CFHT (

The project has encountered unanticipated delays due to loss of a key team member and to problems with implementation of a database system. Sky testing during December was canceled, due to a decision to delay further sky work until star catalog, object list, and observing log subsystems are completed. This decision was mainly based on the loss in observing efficiency during earlier TCS IV testing.

In order to get on the sky as soon as possible and continue testing of the core components, we have developed temporary, non-database versions of these key support subsystems. The user interfaces are similar to the intended, final versions, but the infrastructure uses simple, flat files. These interfaces should permit a good evaluation by the Observing Assistants, and much of them should be reusable in the final version, which is still intended to use a database approach. They should also permit more routine use of the system without losing observing efficiency.

Presently the plan is to test as much as possible, and to begin full time observing support during the first semester of 1998. TCS III should be eliminated for all observing by the end of the first semester, and fully retired by the end of the year.

Final decisions have been made to keep the present Prime Focus Bonnette control system until the Prime Focus upper end is retired. In order to accommodate control of this subsystem, TCS IV has implemented CAMAC support under EPICS. Initially included in the design, it was later eliminated when the PFB control system was to be rebuilt. With the reimplementation of CAMAC, it has also been decided to support dome rotation control and TV information displays under CAMAC. This will result in less overall work for both the TCS IV team and the Electronics Group, and will provide better switch back capability for using TCS III in case of emergency.

The project has upgraded to the latest stable version of EPICS, and has taken advantage of some of the features this version supports.

Editor: Dr. T. M. C. Abbott,
Copyright © 1998, CFHT Corporation. All rights reserved.