Rockwell Automation 57C610 Enhanced Basic Language, AutoMax - Manual (Page 51)

6Ć11
When BASIC executes a GOSUB, it stores the return location of the
statement following a GOSUB.
Each time a GOSUB is executed, BASIC stores another location.
Each time a RETURN is executed,BASIC retrieves the last location
and transfers control to it. In this way, no matter how many
subroutines there are or how many times they are called, BASIC
always knows where to transfer control.
100 IF MOTOR_SPEED%
110 GOSUB 200
120...
130...
140...
.
.
.
200 ! THIS IS A COMMENT
210 MOTOR_SPEED%=MOTOR_SPEED%+(GAIN%/2)
.
.
.
290 RETURN
The ON GOSUB statement has the following format:
ON integer_expression GOSUB line number_1,...,line number_N
where:
integer_expression =
any arithmetic expression that results in an
integer value
line_number_1,..., line_number_N =
line numbers to which control is transferred
depending on the evaluated expression
Line numbers always correspond to the value of the expression. The
value 1 transfers control to the first line number listed. The value 2
transfers control to the second line number listed, etc. There is no
corresponding line number for zero (0). Fractional numbers are
truncated to an integer value. If no corresponding line number exists
for the result of the integer expression, control falls to the next
sequential statement after the ON GOSUB. When a RETURN is
executed from one of the subroutines referenced in the ON GOSUB,
it returns to the next statement after the ON GOSUB.
The following are valid ON GOSUB statements:
20 ON (A% + B% + C%) GOSUB 103,220,475,650
30 ON GAIN% GOSUB 200,300,400,500