Optima DMC-1xxx and DMC-18x2 Command Reference
LI
i
122
LI
FUNCTION: Linear Interpolation Distance
DESCRIPTION:
The LI a,b,c,d command specifies the incremental distance of travel for each axis in the
Linear Interpolation (LM) mode. LI parameters are relative distances given with respect
to the current axis positions. Up to 511 LI specifications may be given ahead of the
Begin Sequence (BGS) command. Additional LI commands may be sent during motion
when the controller sequence buffer frees additional spaces for new vector segments.
The Linear End (LE) command must be given after the last LI specification in a
sequence. This command tells the controller to decelerate to a stop at the last LI
command. It is the responsibility of the user to keep enough LI segments in the
controller's sequence buffer to ensure continuous motion.
LM ? Returns the available spaces for LI segments that can be sent to the buffer. 511 returned
means the buffer is empty and 511 LI segments can be sent. A zero means the buffer is
full and no additional segments can be sent. It should be noted that the controller
computes the vector speed based on the axes specified in the LM mode. For example,
LM ABC designates linear interpolation for the A,B and C axes. The speed of these axes
will be computed from VS
2
=AS
2
+BS
2
+CS
2
where AS, BS and CS are the speed of the
A,B and C axes. If the LI command specifies only A and B, the speed of C will still be
used in the vector calculations. The controller always uses the axis specifications from
LM, not LI, to compute the speed. The parameter n is optional and can be used to define
the vector speed that is attached to the motion segment.
The LI command will apply to the selected coordinate system, S or T. To select the
coordinate system, use the command CAS or CAT.
ARGUMENTS: LI n,n,n,n,n,n,n,n <o >p or
LIA=n where
n is a signed integer in the range -8,388,607 to 8,388,607 and represents the incremental move
distance (at least one n must be non-zero).
o specifies a vector speed to be taken into effect at the execution of the linear segment. o is an
unsigned even integer between 0 and 12,000,000 for servo motor operation and between
0 and 3,000,000 for stepper motors.
p specifies a vector speed to be achieved at the end of the linear segment. Based on vector
accel and decal rates, p is an unsigned even integer between 0 and 12,000,000 for servos,
and between 0 and 3,000,000 for steppers.
USAGE: DEFAULTS:
While Moving
Yes
Default Value
-
In a Program
Yes
Default Format
-
Command Line
Yes
Controller Usage
ALL CONTROLLERS
RELATED COMMANDS:
"LE "
Linear end
"LM "
Linear Interpolation Mode
EXAMPLES:
LM ABC
Specify linear interpolation mode
LI 1000,2000,3000
Specify distance
LE Last
segment
