Galil DMC-2X00 - Manual (Page 97)

To specify vector commands the coordinate plane must first be identified. This is done by issuing the
command CAS to identify the S plane or CAT to identify the T plane. All vector commands will be
applied to the active coordinate system until changed with the CA command.
Specifying Vector Segments
The motion segments are described by two commands; VP for linear segments and CR for circular
segments. Once a set of linear segments and/or circular segments have been specified, the sequence is
ended with the command VE. This defines a sequence of commands for coordinated motion.
Immediately prior to the execution of the first coordinated movement, the controller defines the current
position to be zero for all movements in a sequence.
NOTE: This ‘local’ definition of zero does not affect the absolute coordinate system or subsequent
coordinated motion sequences.
The command, VP xy specifies the coordinates of the end points of the vector movement with respect
to the starting point. Non-sequential axes do not require comma delimitation. The command, CR r,q,d
define a circular arc with a radius r, starting angle of q, and a traversed angle d. The convention for q
is that zero corresponds to the positive horizontal direction and, for both q and d, the counter-clockwise
(CCW) rotation is positive.
Up to 511 segments of CR or VP may be specified in a single sequence and must be ended with the
command VE. The motion can be initiated with a Begin Sequence (BGS) command. Once motion
starts, additional segments may be added.
The Clear Sequence (CS) command can be used to remove previous VP and CR commands which
were stored in the buffer prior to the start of the motion. To stop the motion, use the instructions STS
or AB1. ST stops motion at the specified deceleration. AB1 aborts the motion instantaneously.
The Vector End (VE) command must be used to specify the end of the coordinated motion. This
command requires the controller to decelerate to a stop following the last motion requirement. If a VE
command is not given, an Abort (AB1) must be used to abort the coordinated motion sequence.
It is the responsibility of the user to keep enough motion segments in the DMC-2x00 sequence buffer
to ensure continuous motion. If the controller receives no additional motion segments and no VE
command, the controller will stop motion instantly at the last vector. There will be no controlled
deceleration. LM? or _LM returns the available spaces for motion segments that can be sent to the
buffer. 511 returned means the buffer is empty and 511 segments can be sent. A zero means the
buffer is full and no additional segments can be sent. As long as the buffer is not full, additional
segments can be sent at PC bus speeds.
The operand _CS can be used to determine the value of the segment counter.
Additional commands
The commands VS n, VA n and VD n are used for specifying the vector speed, acceleration, and
deceleration.
VT is the s curve smoothing constant used with coordinated motion.
Specifying Vector Speed for Each Segment:
The vector speed may be specified by the immediate command VS. It can also be attached to a motion
segment with the instructions
VP a,b < n >m
CR r,
θ,δ
< n >m
DMC-2X00 Chapter 6 Programming Motion y 87