CLEARREAD: perform clearing reads on the detectors

This page is part of the ING document INS-DAS-24: client-server interface for control of cameras

Purpose: remove image persistence from previous exposures from the detectors and prepare for an integration.

Actors: udas_run client; udas_camera server; camera.

Outline: the client invokes the clearread action, and the camera reads out the detectors a number of time depending upon the value of the clearreads configuration in the camera configuration file (see ins-das-25). This action is only invoked by the run client if the camera is capable of ndr (non destructive reads).

Normal course of events:

Client invokes the CLEARREAD action on the server, with no arguments.
Server tells the camera to perform clearing reads the detectors and waits for it to finish.
Camera performs readouts on the detectors and takes the detector electonics out of idle mode (i.e. stop the continual clearing of the detectors that happens between observations).
Camera reports that the clearing reads were successful; server returns good status to the client.

Variations:

Camera fails to perform the clearing reads on the detectors or does not respond to the server's command. Server returns an error message to the client and returns status UDAS__CAMCMDFAIL or UDAS__CAMLINKDOWN.