TMC 188/40 Motion Control Module
Appendix C: QSBX/40 Module
Delta Computer Systems, Inc. 360/254-8688
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Readback Parameters
TRANSDUCER COUNTS
This field contains the number of counts read from the quadrature encoder. (Quadrature encoder
counts per revolution = 4 x pulses per revolution.) Since the quadrature encoder counts can
exceed 65535, this field will roll over (reset to zero) every 65536 counts.
NOTE:
If an application uses the Transducer Counts field, it must keep track of the rollovers (the number
of times the counts pass 65,535 and rolls over to 0).
STATUS Word
STATUS Word Bit 6 - Transducer Not Responding
When using an quadrature encoder, Status Word bit 6 is set when the count rate exceeds 800,000
quadrature encoder counts per second (200,000 pulses per second). The bit is not latched and will
be cleared when the count rate falls below 800,000 quadrature encoder counts per second.
NOTE:
An emergency stop will be made when bit 6 is set.
STATUS Word Bit 7 - Out of Limit
Bit 7 equals zero (0) when the Limit input is Active (Within-Limits). It is one (1) when the Limit is
inactive (Out-of-Limit). Since the Limit input is designed to be fail-safe, an inactive input is taken as
an 'Out-of-Limit' condition.
