The CONFIGURE mode and the SET $\backslash$ language

The CONFIGURE mode in OBS is not an observing mode. While OBS is in this mode, several commands are available to specify the current hardware configuration, all pertaining to the SET $\backslash$ language:

• ANTENNA to indicate the station and correlator entry for each antenna.
• DELAY to indicate the zero delay of one antenna
• PHASE to setup the zero phases (LO1 and LO3).
• OBSERVE to resume observations after a configuration change
• POINTING to change the Station and Antenna dependent parameters (IAZ, IEL, IVE, IVN, DVE, DVN)
• SHOW to list some configuration parameter
• XYZ to indicate the position offsets of one antenna on its station

The CONFIGURE mode is obtained by typing command OBS $\backslash$SET MODE CONFIGURE. The OBS $\backslash$ language is then turned off, the SET $\backslash$ language turned on, and the prompt changes to SETUP>. Observations can only resume using the SET $\backslash$OBSERVE command, which turns on the OBS $\backslash$ language, turns off the SET $\backslash$ language, and reset the prompt according to the previous observing mode.

Three commands change the Station.ANk files : SET $\backslash$DELAY, SET $\backslash$POINTING and SET $\backslash$XYZ. One command is placed in the INTER_BASE:START.OBS file : SET $\backslash$ANTENNA. A new INTER_BASE:START.OBS file is created each time a SET $\backslash$OBSERVE command is typed, to ensure that all configuration changes are remembered.