Rockwell Automation 1771-QB Linear Pos. - Manual (Page 141)

Advanced Features
Chapter 9
9-10
Control Word 2: Bits 4 and 5 - Velocity/Position Trigger
These bits indicate if one of the velocity, relative position, or absolute
position triggers is active. If the velocity trigger is active, you must specify
in the trigger velocity/position word, the absolute velocity at which the
trigger condition will be satisfied. If the relative position trigger is active,
the trigger position you specify in the trigger velocity/position words is
relative to the current axis position when the current motion segment began
execution. If the absolute position trigger is active you must specify an
absolute position in the trigger velocity/position words.
Important: Since it is unlikely that the exact velocity/position of the axis
will precisely equal the trigger velocity/position specified, the trigger
condition is satisfied when the actual velocity/position reaches or crosses
the trigger velocity/position.
Control Word 2: Bits 6 and 7 - INPUT 1 and INPUT 2 Triggers
These bits indicate if INPUT 1 and/or INPUT 2 triggers are active. If an
input trigger is active, it means that the associated discrete input must be
satisfied, based on trigger sensitivity, to cause the execution of the next
motion segment. The trigger sensitivity is specified in the programmable
I/O control word (bits 12 to 15), and can be high/low level or
positive/negative edge.
Control Word 2: Bit 8 - Multiple Trigger Conditions
If more than one trigger condition is active, this bit controls whether all the
specified active trigger conditions (AND) or just one (OR) must be
satisfied. If you specify AND, the active trigger conditions do not
necessarily have to occur at the same time to trigger the next motion
segment. The active trigger conditions can occur in sequence.
Control Word 2: Bit 15 - Desired Position
This bit specifies that the movement profile’s desired position given in this
motion segment is incremental (1) or absolute (0).
Important: Absolute moves define a new endpoint in relation to the
zero-position offset specified in the parameter block. Incremental moves
define a new endpoint in relation to the current axis position at the start of
the current motion segment’s execution.