Yaskawa YASNAC PC NC Programming Manual - Manual (Page 291)

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YASNAC PCNC Programming Manual Chapter 4: Enhanced Level Commands
(6) Undefined Variables
Variables which have not been defined yet are called undefined variables, and their val-
ues are <empty>. The following variables are treated as undefined variables.
• Local variables and common variables (#100 to #299) when the power is turned ON or
the NC is reset.
• Local variables for which arguments are not specified where a microprogram is called
up.
• Local variables which belong to the level of the microprogram from which the execu-
tion of program returns by the execution of M99.
• Local variables and common variables where no values have been set in a micropro-
gram.
• Common variables where no values have been set at the NC operation panel.
• Variable “#0”. (This is always treated as <empty> and must not be entered in the left
side of an operation expression.)
(a) Meaning of <empty>
• If an undefined variable is assigned, the address itself for which it is assigned is disre-
garded.
• If an undefined variable is used in an operation expression, it is treated to have the
variable value of “0” with the exception that it is replaced with <empty>.
#2 = <empty> G00X#2; is equivalent to G00;.
#2 = 0 G00X#2; is equivalent to G00X0;
#2 = <empty> #3 = #2; indicates #3 = <empty>.
#2 = <empty> #3 = # [#2+#2]; indicates #3 = #0 = <empty>.
#2 = <empty> #3 = #1*#2; indicates #3 = <empty>.
#2 = <empty> #3 = #2+#2; indicates #3 = <empty>.
#2 = <empty> #3 = #2/#2; indicates #3 = <empty:>
#2 = <empty> #3 = 5*#2; indicates #3 = <empty>.
#2 = <empty> #3 = 2-#2; indicates #3 = 2.
#2 = <empty> #3 = 5/#2 causes division error.