Servo Operational Commands

The central control station sends commands to a group of antennas via an optical fiber link (see Chapter 24). Some of the operational commands, related to the servo is described next.

1. COLDSTART: On receiving this command, the servo system removes the stow-lock pins, releases the motor brakes, enables the servo amplifiers, holds both the axes at the current angle and waits for next command.
2. MV arg1,arg2: Move along the azimuth and elevation axes to the angles arg1 and arg2 respectively. The servo system releases the motor and moves the antenna.
3. TRACK arg1,arg2,arg3: Track in azimuth and elevation axes with the destination angle as arg1 and arg2 and the time parameter as arg3.
4. HOLD: Holds both the axes. On receiving this command, servo system releases brakes of both axes motors and holds the antenna in position.
5. STOP: Stops both the axes. On receiving this command, servo system disables amplifiers & applies brakes to both axes motors.
6. CLOSE: Close the observations. On receiving this command, servo system positions the elevation axis to 90:00:00 deg., disables all amplifiers, applies brakes to all motors & inserts the stow-lock pin.
7. STOW: Inserts the stow-in pin in the elevation axis and locks the axis.
8. SWRELE: Releases stow-in pin from the elevation axis and frees the axis.
9. RSTSERVO: Resets the station servo computer.