## The Tasks and Programs

The software is organised in two basic blocks:

- Real-time tasks that monitor the antenna and receivers:
  - INTERP: this task dialog with the antenna microprocessors every second, and occasionaly send command to them.
  - FLAG1S: this task is a time checker. It is activated every second through a dialog with the Clock microprocessor. It also handles the meteo parameters.
  - ASTRJ : this task does the astronomical computations to prepare the input to INTERP. It is activated every time a new source is requested.
- Tasks that control and perform the acquisition:
  - CORREL: this task controls the correlator data acquisition.
  - CORREL_SPECTRA: this task reads the data from the correlator micro when acquisition is finished.
  - OBS : High level observing program, with integrated observing procedures. Only one occurence of OBS can be running on BURE1.
  - RDI : interferometric data acquisition program.
- Control and display tasks:
  - XAFF : perform various display tasks, including computation of the running amplitudes and phases.
  - STSA : this program is used to display the antenna parameters related to the pointing.
  - STSH : this program is used to display antenna parameters related to “survival” (de-icing, etc...).

The OBS program is intended to provide complete normal operation of the instrument. Accordingly, OBS assumes it has complete control over the system.