Manual

Detailed Descriptions of ACL Commands 3-67
VA <x1>, <y1>, <x2>, <y2>, <varid> Compute Vector Angle
The VA command computes the angle of a vector which passes through the specified points.
<x1> and <y1> define the start of the vector, while <x2> and <y2> define its endpoint;
these parameters can range from -32768 through 32767 and are rounded to the nearest
integer.
The angle is computed in degrees, with zero degrees being to the right (i.e., along the
positive X axis) and positive angles being counterclockwise from zero. The angle result is
placed in the variable given by <varid>; the range of values is 0.0000 through 359.9999.
If (<x1>, <y1>) and (<x2>, <y2>) are the same point then the VA command returns 0.0000
as the angle.
For more information about ACL variables, please see Chapter 10.
VC <varid> Variable Capture
The VC command modifies the behavior of the next ACL output command (OA, OC, etc.).
Instead of sending the numeric values to the host computer, the output command places the
values into the variable whose i.d. is given by <varid> and, if necessary, in subsequently-
numbered variables. For example, the sequence VC 5; OL; causes the current travel limits
to be placed in variables 5, 6, 7, and 8.
An OI ("Output Identification") command following VC causes the numeric values of the
two ROM version numbers to be captured. For example, if OI outputs AUTOMOVE REV
3.11, 3.1 the captured values will be 3.11 and 3.1.
If an IN ("Initialize") command occurs after the VC but before any ACL output command,
the effect of the VC is canceled.
For program clarity it is suggested that the VC command be immediately followed by the
ACL output command. In any case, if the VC is in a Download Sequence, the ACL output
command must be in the same Download Sequence. The output command must not be in a
Download Sequence called by the one containing the VC, and must not be in a Download
Sequence which called the one containing the VC.
Note: VC does not work with escape sequences in the ES command. For example, there
is no way to capture the output of the
ESC.E ("Output Communications Error")
command.
For more information about ACL variables, please see Chapter 10.
VL <x1>, <y1>, <x2>, <y2>, <varid> Vector Length
This command computes the length of a vector. The Pythagorean theorem is used, where the
length of the vector is the square root of: the square of the X coordinate change plus the
square of the Y coordinate change.