Use Case:  Select observing instrument

Description:  This command is used to select the observing instrument.
After this command ATCS is configured with all the parameters for this instrument.
All instrument configuration data can be changed at any time with Set instrument data

Role(s)/Actor(s): 
Primary: VLTICS-ISS
Secondary: All sub-systems

Priority: Major

Performance:  Some seconds

Frequency:  Every time a new instrument or a new configuration of an instrument is selected.

Package Assignment:  Mode Switching.

Preconditions:

• ATCS is ONLINE or STANDBY

• Send command to select instrument
  Exception course: Command failed
• ATCS checks if a configuration is available
  Exception Course:No instrument configuration available
• ATCS marks selected configuration as active
• ATCS configures all sub-systems to use the new active configuration
• ATCS returns OK reply

Exception Course: Command failed

• ATCS returns ERROR reply

Exception Course:No instrument configuration available

• ATCS returns ERROR Reply

Postconditions:

• Configuration of selected instrument is marked active and used by all concerned sub-systems

Issues to be Determined or Resolved:

Notes:if msw focus is used for setting the location of the AT, remember that if the instrument is configured to be allocated to a specific station, the software would refuse to do it.
The UC is kept although it seems no need is identfied yet.

Last modified: Thu Jun 28 13:33:23 UTC 2001