Problems due to tasks

1. The control software has stopped and the displays are not updating.

   The likeliest problem is that the 10 Hz task has paused. There may be a message like TNHZ: ARITH-ERR AE5A on the System Console. Type

   D(ISPLAY) M(EMORY)

   on the System Console and look at the line beginning TNHZ. If the task is paused (P) rather than active (A), try continuing it:

   T(ASK) TNHZ; CO(NTINUE)

   If this doesn't work, restart it:-

   RESTART TNHZ

   If ARITH-ERR's occur on every cycle, then TNHZ is probably being fed rubbish by the time service or the encoders. Call the Duty Technician.

2. There is a continuous stream of LOGQ-ERR's on the System Console.

   If TNHZ is the task responsible, you will not be able to recover control without either removing the 10 Hz interrupt line from the box on the wall in the CLIP Centre (it may be labelled) or rebooting the computer. The latter is preferred.

3. The Autoguider Panel on the Control Desk is not working.

   Check that the task AUTOGUID is alive. If not:-

   RESTART AUTOGUID

4. The Acquisition & Guiding Panel on the Controle Desk is not working.

   Check that the task AGBX is active. If not:-

   RESTART AGBX

5. The Beckmann Displays are working, but the Information Display is not updating.

   In this case, the 10-Hz synchronous task (TNHZ) is running, but the Information Display task (INFODISP) is not. If the latter is paused, try to continue it:

   T(ASK) INFODISP; CO(NTINUE)

   and if this fails:

   RESTART INFODISP

6. The User Interface terminal hangs up and gives no response.

   Check on the System Console whether Task USER (or any other) has failed with an error message. Type on the System Console:-

   RESTART USER (or whichever task it was)

   If the User Interface does not now restart, try stopping and restarting the telescope control system with FINISH and GO INT.