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Motor Controller Tango Device Server

A server to expose a bliss motor controller over Tango. This can be used to share controllers that would normally handle a unique connection (e.g. PI_E753 controllers).

Launching the server process

(base) user@beamline:~/bliss$ conda activate bliss
(bliss) user@beamline:~/bliss$ export TANGO_HOST=localhost:20000

(bliss) user@beamline:~/bliss$ BlissMotorController -?
usage :  BlissMotorController instance_name [-v[trace level]] [-nodb [-dlist <device name list>]]
Instance name defined in database for server BlissMotorController :

(bliss) user@beamline:~/bliss$ BlissMotorController test
Ready to accept request

Server Configuration (with Beacon)

In a .yml file declare the motor controllers that should be served.

  - class: MotorControllerDevice  # one tango device class
    tango_name: id00/tango/remo_ctrl   # cf DeviceProxy( tango_name )
      beacon_name: remo_ctrl # name of the motor controller object (not the axis name)

# - [...]

personal_name: test
server: BlissMotorController
  • tango_name: the name of the Tango Device in the form domain/family/member
  • beacon_name: the name of the motor controller that will be served (it must already exist in the Beacon configuration)
  • personal_name: the name used in the command line to launch the server process

Client Configuration (with Beacon)

In a .yml file declare the motor controller objects. The only difference with usual controllers is the tango-server section.

- name: remo_ctrl
  class: mockup
      tango_name: id00/tango/remo_ctrl
      module: motors.tango_motor_controller
      class: TangoMotorController
    - name: remo
      steps_per_unit: 10
      velocity: 1000
      acceleration: 100

Now, from your Bliss session you can import the axis (and thus its controller) as usual:

BLISS [1]: config.get("remo")
  Out [1]: AXIS:
                name (R): remo
                unit (R): None
                offset (R): 0.00000
                backlash (R): 0.00000
                sign (R): 1
                steps_per_unit (R): 10.00
                tolerance (R) (to check pos. before a move): 0.0001
                motion_hooks (R): []
                limits (RW):    Low: -inf High: inf    (config Low: -inf High: inf)
                dial (RW): 0.00000
                position (RW): 0.00000
                state (R): READY (Axis is READY)
                acceleration (RW):  100.00000  (config:  100.00000)
                acctime (RW):        10.00000  (config:   10.00000)
                velocity (RW):     1000.00000  (config: 1000.00000)
                velocity_low_limit (RW):            inf  (config: inf)
                velocity_high_limit (RW):            inf  (config: inf)
           Controller: remo_ctrl (TangoMotorController)

           MOCKUP AXIS:
               this axis (remo) is a simulation axis


BLISS [2]:

The axis and its controller can now be used the same way as in local setup.

Note that the axis is purely local, only the controller is shared through Tango. Each session using this controller will own an axis instance, but all instances are kept in sync by Redis.