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GBT Balance Usage

• GBT Balance Usage
• 1. Balancing from the python command line
• 2. Balancing from the astrid "Command Console"

1. Balancing from the python command line

To balance the prime focus receiver and the IFRack

• From python import the Balance module by typing:

          from Balance import *
is this correct? didn't work during integ tests 2/9; had to use gbt.something.config.Balance

• Create a Balance object with a list of the devices to be balanced. Supported devices are "acs" (Spectrometer), "ifrack" (IF Rack), "pf" (Prime Focus Receivers) and "sp" (Spectral Processor).

          b = Balance(("pf", "ifrack"))   
Are inside parens supposed to be brackets??

• To perform the balance, the balance method is called.

 
        b.balance()

An optional parameter to the balance method can be provided. This parameter must be a dictionary that contains 1 or more of the following balancing options. Items which are not in the dictionary are assigned their default values. Non applicable options are ignored.

The default values are:

             target_level =  -11   Applicable when balancing the SpectralProcessor (sp)    :
             port = (1..41)        Applicable when balancing the Spectrometer (acs)   
             sample_time = 2       Applicable when balancing thePrimeFocusReceivers(pf)  
             cal = 'off'           Applicable when balancing the PrimeFocusReceivers(pf)  
              

Supported dictionary keys/value type are:

        target_level / float
        sample_time  / int
        cal / string containing "on" or "off" -- other values will be treated as if "on" was specified
        port/ tuple containing integers from 1 to 41

An example of a dictionary containing valid options and its use in a balance method call is:

         b = Balance(("pf", "ifrack, acs"))   

         opt = { "target_level": 4, 
                 "sample_time" : 5,
                 "cal"         : "on",
                 "port"        : (9,13)
                }
         b.balance(opt)

• The IF target level for the Prime focus receiver is 4.

• The sample time used in the prime focus receiver is 5 seconds.

• The cal diodes will not shut off during balancing.

• The duty cycles for ACS ports 9 and 13 will be displayed after completion of the ACS balancing.

2. Balancing from the astrid "Command Console"

Directions are the same as for "Balancing from the Python Command Line" (step 1 above), but the

import

3. Balancing from the Config Tool

The config tool provides its own interface to the Balance API. The interface is through one method called bal().

The bal() method accepts the following optional parameters:

• mgrs = a list of devices to be balanced ( Supported devices are "acs", "ifrack", "pf" and "sp" )

• options = a python dictionary that contains balancing options

• sim = a simulation flag . Setting sim = 1 will cause the bal method to not actally balance the devices

All the parameters are optional. The default values for these parameters are:

• mgrs : ("ifrack",)

• options : { "target_level" : -11, "sample_time" : 2, "cal" : "off", "port" : (1..41) }

• sim : 0

To perform a balance from the config tool interface type :

   g = gbtsetup()

   g.bal()

The command:

   g.bal(mgrs=("pf", "ifrack", "acs"))

Alternately to specify balancing options

         opt = { "sample_time" : 5,
                 "cal"         : "on",
                 "port"        : (9,13)
                }
   
      b.bal(mgrs=("pf", "ifrack", "acs"), options = opt)

The Prime Focus receiver will be balanced with the sample_time of 5 and the cal diodes "on" (if they are currently "on")

The IFRack will be balanced. Note that there are no balancing options for the IFRack

The Spectrometer will be balanced with the resulting duty cycles displayed for ports 9 and13

4. Core Team

-- MelindaMello - 07 Dec 2004