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1. Optionally, create a group .
2. Create a knob
3. Add devices:
   1. Do this "by hand" if you know the PV. Eg YCOR:IN20:492:BDES
   2. Do this by "drilldown" (which uses physics name). In the Editor:
      1. Select a model sequence: Eg BXG TO BX01. Note that sequences are in alphabetical order. That is on the fix list.
      2. Select a device "type". Note that the type names given are:
         1) SNS type names, which themselves use >1 name eg hcorr == dch == horrzcorr => X correctors.
         2) and also flattened hierarchy of types, eg type "dipole" includes hcorr and vcorr.
      3. Select a device name, by "physics name".
      4. Select FieldSet (not FieldRB). (issue: FieldRB should not be offered).
   3. Or calculate bump knobs
      1. Select a section of contiguous sequence of sections (a "combo sequence") Accelerator->Sequences
         BXG TO BX01 - BX01 to BX02 works.
      2. Knobs->(Make Horizontal Bumps | Make vertical bumps) Make Horizontal Bumps (Make Vertical Doesn't work, since it seems so many of our correctors are SLC!)
      3. For Horizontal Bumps: These setups were tested.
         1. Design Offset 3 (default) magnets - works (4 magnet doesn't work!)
         2. Design Angle 5 (default) magnets - works
         3. Live Offset 3 - works
         4. Live Angle 5 works - works
      4. For Vertical Bumps, select sections BXG to BX01 - QM15 to FV2
         1. Design Offset 3 (default) magnets - works, but they're mostly SLC magnets, so you can't connect and can't set them.

Problems and Issues

1. Knobs app can't set non-EPICS devices (eg correctors), so;
   1. In "drilldown" mode it offers you devices to set that it can't in fact set (eg having selected BX02 TO QM15, you select Y corrector YC21303 (which is in fact an SLC CS corrector), select FieldSet (whch which you shouldn't have been able to do) and then it can't connect.
      WORK AROUND: Be conscious of what's SLC and what EPICS. See resources 0,1.
   2. It makes bumps using correctors it can't set!
      Eg: Select sequence indexes 2,3,4,5. Make Vertical design offset knobs. The first knob created is BPM21301. This contains 3 correctors, all SLC! Eg YXC21303 - YCOR:LI21:303. So, knob can't be implemented. This problem seems particularly acute for Vertical bumps! Are more of our horizontal correctors EPICS?
      NO work around. *Will have to fix so that that elements which are not settable="true" in the xdxf file, are not included.
2. Knobs->"Proprotional Coefficients" spelt wrongly.
3. Knobs Editor uses SNS type names, which themselves use >1 name eg hcorr == dch == horrzcorr => X correctors.