
59
K-Cube Brushed DC Servo Motor Driver
Output Trigger Modes
When the
Trig 1 Mode
and
Trig 2 Mode
parameters are configured as outputs, the
TRIG ports can be used as a general purpose digital output, or to indicate motion
status or to produce a trigger pulse at configurable positions as follows:
Digital Output
- General purpose logic output (set using the LLSetGetDigOPs
method).
Trig Out In Motion
- Trigger output active (level) when motor 'in motion'. The output
trigger goes high (5V) or low (0V) (as set in the Trig 1. Polarity and Trig. 2 Polarity
parameters) when the stage is in motion.
Trig Out Max Vel
- Trigger output active (level) when motor at 'max velocity'.
Trig Out Pos. Steps Fwd
- Trigger output active (pulsed) at pre-defined positions
moving forward. Only one Trigger port at a time can be set to this mode. See
Trigger Out Position Steps for further details.
Trig Out Pos. Steps Rev
- Trigger output active (pulsed) at pre-defined positions
moving backwards. Only one Trigger port at a time can be set to this mode. See
Trigger Out Position Steps for further details.
Trig Out Pos. Steps Both
- Trigger output active (pulsed) at pre-defined positions
moving forwards and backward. Only one Trigger port at a time can be set to this
mode. See Trigger Out Position Steps for further details.
Trigger Out Position Steps
In the last three modes described above, the controller outputs a configurable number
of pulses (set in the
Num. Pulses Fwd
and
Num. Pulses Rev
parameters), of
configurable width (
Trig Pulse Width
), when the actual position of the stage matches
the position values configured as the Start Position and Position Interval (
Start Pos.
Fwd/Start Pos. Rev. and Pos Interval Fwd/Pos Interval Rev
). These modes allow
external equipment to be triggered at exact position values.
The position pulses are generated by dedicated hardware, allowing a very low latency
of less than 1 usec. The low latency of this triggering mode provides a very precise
indication of a position match (assuming a stage velocity of 10 mm/sec, the less than
1 usec latency would in itself only result in a 10 nm position uncertainty, which is
normally well below the accuracy limitations of the mechanics.)
Using the last three modes above, position triggering can be configured to be
unidirectional (
Trig Out Pos. Steps Fwd
or
Trig Out Pos. Steps Rev
) or bidirectional
(
Trig Out Pos. Steps Both
). In bidirectional mode the forward and reverse pulse
sequences can be configured separately. A cycle count setting (
Num. of Move
Note
If the trigger mode is not set to one of the three position modes described
previously, then the following parameters are not applicable and will be
greyed out.