SPEC is a UNIX-based software package for instrument control and data acquisition widely used for X-ray diffraction at synchrotrons around the world. It is used on the MX beamlines to control beamline motors, etc. There are shell windows on each beamline in which SPEC runs. The sessions have different names depending on which beamline you are on:

Beamline Spec session name (Experimental hutch) Spec session name (Optics hutch)
ID14-4 eh4 oh2
ID23-1 eh1 oh1
ID23-2 eh2 oh2
ID29 exp oh
BM29 exp optics
ID30A-1 massif1 -
ID30A-2 massif2 -
ID30A-3 massif3 -
ID30B - -

The spec session must be running to collect data. This can be started and stopped from the icons on the control computer of each beamline control PC. If it is not running you will not be able to move any motors and the motor values in MxCuBE will be shaded red.