STE 58762 2-11
Should you change the contents of a system variable related to movement control, that change will
not take effect until the next motion; it will have no effect at all on a motion in progress at the time;
However, by using a WITH construct, it is possible to temporarily set a system variable with regards
to one motion command. For example:
MOVE Al WITH SPEED = 50
Furthermore, be warned that SCOL does not check to see whether a value substituted into a
system variable is within the permissible range. Sho uld the value not be in the permissible range,
SCOL will do one of two things:
• Sh ould you try to insert a value less than the minimum permissible value, the minimum
permissible value will be entered in its place.
• Sh ould you try to insert a value greater than the maximum permissible value, the maximum
permissible value will be entered in its place.
Refer to Chapter 3 for details on how to use system variables.
2.4.4 System Constants
In order to make programs easier to read (and thereby debug), SCOL provides the system
constants shown in Table 2.2. These names can be substituted into the program in place of
numbers in order to make it easier to see what you are doing. However, be sure to use them only
in the locations specified in the Comments column of Table 2.2. If you use them in other locations,
trying to debug your program can become a real nightmare.
Table 2.2 List of system constants
Name Value Comments (Locations for use)
FREE
LEFTY
RIGHTY
0
1
2
In the system variable CONFIG
In the POINT command
COARSE
FINE
0
1
In the system variable ACCUR
OFF
ON
0
1
In the system variable GAIN
In the SETGAIN command
PAI 3.141593 Pi value
CONT
CYCLE
SEGMENT
0
1
2
In the MODE command