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• If Se<>0, we are likely experiencing a hard reset. In that case:
  • Signal state change to 80 (Hard Reset Initialization)
  • Set Ve (MCode version) to 3 and Pu (Power-Up flag) to 0.
  • Set EL (Encoder lines) to 4096, giving 4096 lines * 4 steps/line = 16384 steps/rev
  • Set MS (Microsteps) to 8, giving 8 uSteps/step * 200 step/rev = 1600 uSteps/rev
  • Set EE (Encoder enabled) to 0, forcing open-loop step mode. Closed-loop mode is too slow because of a 1kHz loop rate.
  • Set S3 (I/O 3 settings) to 16,0,1. This is used for encoder power - sourcing output, active low.
  • Set O3 (Output 3) to 1, turning the encoder on.Set S4 (I/O 4 settings) to 16,0,0. This is used for fan power - sinking power, active low.
  • Set O4 (Output 4) to 1, turning the fan on.Set S13 (I/O 13 settings) to 60,0,0. This is used for input signaling, and makes it available to the input capture trip (interrupt)
  • Set FC (Filter Capture) to 9. This sets a debounce filter on input 13 with a 12.9usec delay time.
  • Set HT (Hold Time) to 5, setting the hold current delay time to 5ms.
  • Set RC (Run Current) to 100, making 100% of current available for movement.
  • Set HC (Holding Current) to 5.
  • Set NE (Numeric Enable) to 0, to prevent errant communications as being interpreted as movement commands.
  • Set Sw (Sweep Distance) to 50 steps.
  • Set Sr (Encoder Sweep Distance) to 512 counts.
  • Reset Dr (Drift) to 0.
  • Reset Dl (Drift limit) to 23.
  • Reset P0 (Open position) to 0.
  • Reset P1 (Positive closed position) to P0+Sw = 512.
  • Reset P2 (Negative closed position) to P0-Sw = -512.
  • Reset N0 (Open encoder position) to 0.
  • Reset N1 (Positive closed encoder position) to N0+Sr.
  • Reset N2 (Negative closed encoder position) to N0-Sr.
  • Pre-load shadow register Cs=C2 (this doesn't actually do anything and may be eliminated in a future revision)
  • Set Ec=1 to turn error checking on.
  • Reset drift violation counters Ud and Ld to 0.
  • Reset Df to 99 (current slit position is unknown)
• For both hard and soft resets, we do the following
  • Signal state change to 81 (Soft Reset Initialization)
  • Disable any trips (TE=0)
  • Hold for 100ms to let things stabilize.
  • Reset Hb (heartbeat) to 0.
  • Set Se (Mode Select) to 0
  • Goto Mode Select Loop

Mode Select Loop (LB Za)

• • Set O3 (Output 3) to 1, turning the encoder on. This is necessary because O3 is not saved in NVRAM.
  • Set O4 (Output 4) to 1, turning the fan on. This is necessary because O4 is not saved in NVRAM.
  • Goto Mode Select Loop

Mode Select Loop (LB Za)

• Mode Select Loop START (forever):
  • Signal state change to 0 (Mode Select)
  Mode Select Loop START (forever):
  • Signal state change to 0 (Mode Select)
  • If Se=1, branch to Mode 1: One-Shot
  • If Se=2, branch to Mode 2: Flip-Flop
  • If Se=3, branch to Mode 3: Burst
  • If Se=4, branch to Mode 4: Fast Open
  • If Se=5, branch to Mode 5: Fast Close
  • If Se=7, branch to Mode 7: Home
  • Increment heartbeat
  • Hold for 100ms
• Mode Select Loop END

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The magic offsets are normally stored in IMS NVRAM, but in case they are lost, refer to the table above.

Changelog

Version Ns=

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93 (pcds_motion R2.3.

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13)

• Moved O3 and O4 initializers to run on soft resets as well as on hard resets. This avoids a power-up edge case where, if the motor is powered up with Se=0, the encoder would not power up, making the spindle run haywire upon homing.

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• Release version of Ns=91
• Adjusted default drift limit Dl to 46 encoder counts (~1 degree)
• Wishlist for next revision:
  • Test realignment subroutine (X7) and add it to every mode change (especially fast open/close modes)
  • Further velocity tuning? We could possibly go faster.

Version Ns=92 (pcds_motion R2.3.12)

• Release version of Ns=91
• Adjusted default drift limit Dl to 46 encoder counts (~1 degree)

Version Ns=91 (Non-Release)

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