Slits configuration

This chapter presents a typical usage of BLISS to configure and test standard slits.

The example is based on configuration of secondary slits of ID21.

To ease readability, the configuration of only one pair of blade is described here, but the example can easily be extended to 2 pairs.

Real motors

First part of the file is the configuration of real motors. In the case of the slits of ID21, the real motors are driven by Icepap. Icepap configuration gives full details of Icepap motors configuration.

• Note the negative sign to fix cabling choice: user convention is to be positive when opening slits
• NB: name field is mandatory for Beacon Web Config tool to recognize device as a motor.

  -
    controller:
      class: IcePAP
      host: iceid219
      name: secondary_blades
      axes:
          -
              name: ssf
              address: 23
              steps_per_unit: -1000     <--- negative sign.
              velocity: 1
              acceleration: 8
              backlash: 0.05
          -
              name: ssb
              address: 24
              steps_per_unit: -1000
              velocity: 1
              acceleration: 8
              backlash: 0.05
  

Virtual axes

Second part is the configuration of new virtual axes based on real axes.

• The role of each blade is defined using the tags keyword
  • real means the axis is a real motor, declared elsewhere
  • front, back, hgap, hoffset are specifiers for each axis
• The plugin is not specified in secondary_slits.yml, because a __init__.yml with plugin: emotion already exists in the directory
• slit_type: can be horizontal or vertical or both (default value)

  -
    controller:
      class: slits
      name: secondary_slits
      slit_type: horizontal
      axes:
          -
              name: $ssf  <----------  The existing 'ssf' axis,
              tags: real front  <----  has got the role of *real front* axis.
          -
              name: $ssb
              tags: real back
          -
              name: sshg <------------ The (new) virtual axis 'sshg',
              tags: hgap      <------- is the *horizontal gap* axis.
              tolerance: 0.04
          -
              name: ssho <------------ The (new) virtual axis 'ssho',
              tags: hoffset   <------- is the *horizontal offset* axis.
              tolerance: 0.04