Reference Guide

PMAC Quick Reference Guide
78 Appendix B – PMAC I-Variables Summary
Motor Servo Loop Modifiers Range Default Units
Ix57 Motor x Continuous Current Limit 0 .. 32,767 0 Bits of a 16-bit DAC
Ix58 Motor x Integrated Current Limit 0 .. 8,388,607 0 230 (DAC bits)2 * servo cycles
Ix59 Motor x User Written Servo
Enable
0 .. 3 0 None
Ix60 Motor x Servo Cycle Period
Extension
0 .. 255 0 Servo Interrupt Periods
Ix63 Motor x Integration Limit -8,388,608 ..
8,388,607
4194304 1/16 count
Ix64 Motor x 'Deadband Gain' -32,768 .. 32,767 0 (no
deadband)
None
Ix65 Motor x Deadband Size 0 .. 32,767 16 (=1 count) 1/16 count
Ix67 Motor x Position Error Limit 0 .. 8,388,607 4,194,304 1/16 count
Ix68 Motor x Friction Feedforward -32,768 .. 32,767 0 DAC bits
Ix69 Motor x DAC Limit 0 .. 32,767 20,480
(~6.25V)
DAC bits
Commutation I-Variables Range Default Units
Ix70 Motor x Number of Commutation
Cycles
0 .. 255 1 Commutation cycles
Ix71 Motor x Counts/N Commutation
Cycles
0 .. 8,388,607 1000 Counts
Ix72 Motor x Commutation Phase
Angle
0 .. 255 85 (=120° e) 360/256 elec. deg. (1/256
commutation cycle)
Ix73 Motor x Phase Finding Value 0 .. 32,767 0 bits of 16-bit DAC
Ix74 Motor x Phase Finding Time 0 .. 255 0 Servo Interrupt Cycles (for Ix80 = 0
or 1)
Servo Interrupt Cycles*256 (for
Ix80 = 2 or 3)
Ix75 Motor x Power-On Phase Position
Offset
-8,388,608 --
8,388,607
0 Encoder counts * Ix70
Ix76 Motor x Velocity Phase Advance
Gain
0 .. 8,388,607 0 Angle/Vel
Ix77 Motor x Magnetization Current -32,768 .. 32,767 0 DAC bits
Ix78 Motor x Slip Gain 0 .. 8,388,607 0 238 (electrical cycles/update)/DAC
bit
Ix79 Motor x 2nd Phase DAC Bias -32,768 .. 32,767 0 DAC bits
Ix80 Motor x Power On Mode 0 .. 3 0 none
Ix81 Motor x Power-On Phase Position
Address
PMAC addresses $0 Extended PMAC or multiplexer-port
addresses
Ix83 Motor x Ongoing Position
Address
PMAC addresses see Ix83 table Legal PMAC 'X' and 'Y' addresses
Further Motor I-Variables Range Default Units
Ix85 Motor x Backlash Takeup Rate 0 .. 8,388,607 0 (1/16 Counts) / Background Cycle
Ix86 Motor x Backlash Size 0 .. 8,388,607 0 1/16 Count