796 HEIDENHAIN Technical Manual MANUALplus 620
Renewed 
traversing of the 
reference marks
Module 9220 Traverse the reference mark
The module starts the reference mark traverse in an axis or servo-controlled 
spindle. If the reference mark has already been evaluated, it can be evaluated 
again by this module. The module can be called in all operating modes.
Constraints:
 Software limit switches are not effective.
 The sequence of functions is determined by MP_refType.
 The velocity and the direction for traversing the reference marks are either 
taken from MP_refFeedHigh and MP_refDirection (CfgReferencing) or 
they are defined in the module.
 An axis cannot be started for referencing until all other axes are in position.
 If an axis is started for reference point traverse although the reference mark 
has already been traversed, NN_AxReferenceAvailable is reset and the 
reference mark is evaluated again. The same constraints apply as when 
traversing the reference mark for the first time.
 If the spindle is started for reference point traverse, the marker 
NN_SpiReferenceAvailable is set.
 The spindle must be started from a standstill to traverse the reference mark.
Call:
PS B/W/D/K <>Axis/spindle>
Index from CfgAxes/axisList
PS B/W/D/K <>Feed rate/shaft speed>
0: Feed rate/shaft speed from CfgReferencing/refFeedHigh
>0: Feed rate in mm/min or shaft speed in 1/1000 min
–1
 
PS B/W/D/K <>Direction of traverse>
–1: Negative direction
0: Direction from CfgReferencing/refDirection
1: Positive direction
CM 9220
PL B/W/D <>Error code>
0: Reference mark traverse is commanded
1: Non-existent axis or open-loop spindle
2: Inadmissible values for the feed rate / direction
3: Incorrect operating mode
4: Reference traverse already started
5: Axis is already being positioned or the spindle is in motion
6: Other axis is already being positioned
8: Programmed axis not in closed loop
The direction of traverse should be defined in the module only in 
exceptional cases. Since the reference end positions are not considered in 
this case, the limits of the traverse range may be violated.