# SANS Special Commands

Some special initializations for SANS Instruments:

MakeMulti name
  SANS uses a special syntax feature where several motors are grouped into a component group. For example beamstop or detector. MakeMulti creates such a group with the name name. Once such a group has been created, it has to be configured. For this a few configuration commands are available:
  name alias motname compname
    This command makes motor motname available as component motor compname. For example: bs alias bsx x makes motor bsx available as x in the beamstop group. Then the bsx motor can be driven by the command bx x = 12..
  name pos posname motname value motname value ....
    The group command supports the notion of named positions. This means that a special combination of angles can be accessed through a name. This commands defines such a named position with the name posname. posname is followed by pairs of motorname value which define the position.
  name endconfig
    Once a group has been completely defined the configuration process must be ended with endconfig.
MakeSANSWave name velo_name
  > Installs a velocity selector wavelength variable into SICS. The variable will have the name given as first parameter. Usually lambda is a good idea. The second parameter, velo_name, is the name of the velocity selector which is controlled by this wavelength variable. This module contains a hard coded formula which may only be applicable to the SANS at PSI.
MakePSDFrame
  This installs a command into SICS which allows to retrieve a detector image from the histogram memory, even in TOF-mode.

Many other commands for controlling collimators, attenuators, beamstops and shutters are implemented in Tcl. These commands use non standardizable hardware such as the Siematic SPS.