Every control command has a full and an abbreviated form which in most cases can be inferred from the DISPLAY output. For example, DISPLAY lists the collimator focus position as ` Col_Focus', from which the commands COL_FOCUS and CF can be inferred. This is not infallible; the short--form command to insert the beam rotator is not R (= READ) but BR (which appears in parentheses on the display).
All low-level commands are of the form:
command value [units] [apply]
where the bracketed items units and apply can be omitted.
value can in addition take the special values MIN and MAX
where it makes sense to do so.
units specifies other than default units (which are mm or degrees
depending on the mechanism) for value.
apply
governs whether offsets are applied to the slit and echelle angles, and
defaults to TRUE.
An acknowledgement is sent immediately after the request for a mechanism to move and a later asynchronous message informs the user when the movement is complete.