Page History

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1. Setting up 180 Hz timing:
   1. Navigate to astahome->Event/ASTA->LLRF->Experts->RF01 Triggers...
   2. This brings up the 'AS01 EVR RF01 Trigger Diags' panel as shown in figure above.
   3. Enable the IRQ button in the first row corresponding to 165. You will see the 'Rate' PV corresponding to this row display '180.0'
2. Setup the feedback rate to 180 Hz:
   1. Then bring up the PAU screen by clicking on 'PAU AS01 Gun' towards the bottom left of above VME panel.
      1. Ensure 'Activate PAU' button is 'ON'.
      2. Ensure Beam code for all the four data slots DS0,DS1,DS2 an DS3 are '0'. This corresponds to LCLS beamcode.
      3. Set the Time slot for DS0 to '2', for DS1 to '4' and for S2 to '6'. These correspond to the three included timeslots TS2, TS4, TS6.
      4. The last data slot is not included in the feedback loop - so it does not matter what it is set to. Leave it at '1'.
      5. For each time slot corresponding to a data slot, there are two sets of patterns.
         1. The first row of patterns are modifier bits that provide inclusion. The second row provide exclusion.
         2. Set the exclusion masks for 'Mod. 2' for DS0,DS1 and DS2 to '0x15'. This excludes TS1,TS3,TS5 timeslots.
      6. For DS4, set it to '0xffffff'. This will exclude the fourth dataslot.
      7. All other modifier bits for all data slots should be set to 0.
      8. Change the Pipeline Index to '1' (from '2').
      9. Reduce the 'Delay (usec)' to '850' (from '970'). We will have to play with this value till we optimize feedback performance.
         This is just a starter value.
      10. The 'Callback call rate (Hz):' field should show 180.00 after these changes. This means feedback is operating at 180 Hz.
          
          Image Added
3. Then bring up the PAU screen by clicking on 'PAU AS01 Gun' towards the bottom left of above VME panel.
   1. Ensure 'Activate PAU' button is 'ON'.
   2. Ensure Beam code for all the four data slots DS0,DS1,DS2 an DS3 are '0'. This corresponds to LCLS beamcode.
   3. Set the Time slot for DS0 to '2', for DS1 to '4' and for S2 to '6'. These correspond to the three included timeslots TS2, TS4, TS6.
   4. The last data slot is not included in the feedback loop - so it does not matter what it is set to. Leave it at '1'.
   5. For each time slot corresponding to a data slot, there are two sets of patterns.
      1. The first row of patterns are modifier bits that provide inclusion. The second row provide exclusion.
      2. Set the exclusion masks for 'Mod. 2' for DS0,DS1 and DS2 to '0x15'. This excludes TS1,TS3,TS5 timeslots.
   6. For DS4, set it to '0xffffff'. This will exclude the fourth dataslot.
   7. All other modifier bits for all data slots should be set to 0.
   8. Change the Pipeline Index to '1' (from '2').
   9. Reduce the 'Delay (usec)' to '850' (from '970'). We will have to play with this value till we optimize feedback performance.
      This is just a starter value.
   10. The 'Callback call rate (Hz):' field should show 180.00 after these changes. This means feedback is operating at 180 Hz.
       
   11. Image AddedFirst disable the VME feedbacks in the 'VME GN1' panel as shown below:
       Image Removed
   Then bring up the PAU screen by clicking on 'PAU AS01 Gun' towards the bottom left of above VME panel.
   1. Ensure 'Activate PAU' button is 'ON'.
   2. Ensure Beam code for all the four data slots DS0,DS1,DS2 an DS3 are '0'. This corresponds to LCLS beamcode.
   3. Set the Time slot for DS0 to '2', for DS1 to '4' and for S2 to '6'. These correspond to the three included timeslots TS2, TS4, TS6.
   4. The last data slot is not included in the feedback loop - so it does not matter what it is set to. Leave it at '1'.
   5. For each time slot corresponding to a data slot, there are two sets of patterns.
      1. The first row of patterns are modifier bits that provide inclusion. The second row provide exclusion.
      2. Set the exclusion masks for 'Mod. 2' for DS0,DS1 and DS2 to '0x15'. This excludes TS1,TS3,TS5 timeslots.
   6. For DS4, set it to '0xffffff'. This will exclude the fourth dataslot.
   7. All other modifier bits for all data slots should be set to 0.
   8. Change the Pipeline Index to '1' (from '2').
   9. Reduce the 'Delay (usec)' to '850' (from '970'). We will have to play with this value till we optimize feedback performance.
      This is just a starter value.
   10. The 'Callback call rate (Hz):' field should show 180.00 after these changes. This means feedback is operating at 180 Hz.
       
       Image Modified

6. Navigate to astahome->RF/Global->Gun->Mux for PDES
This brings up the 'GUN:AS01:1:PDES' panel.

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