Rockwell Automation 57C610 Enhanced Basic Language, AutoMax - Manual (Page 84)

6Ć44
The number of variables in the READ statement does not have to
match the number of expressions in a specific DATA statement.
BASIC will simply go to the next sequential DATA statement in the
program to acquire the value. The variable type and expression
must match.
A READ statement is not legal without at least one DATA statement.
However, you can have more than one DATA statement as long as
there is one READ statement in the program:
10 READ A,B,C,D,E,F
20...
30...
40...
50 DATA 17,25,30
60 DATA 43,76,29
A READ statement can be placed anywhere in a multiĆstatement
line. A DATA statement, however, must be the only statement on a
line.
If you build your READ statement with more variables than you
include in the data block, the system will print an error message
when it attempts to access the next DATA expression and finds one
is not there.
The following is an example of a READ and DATA sequence:
10 READ A%,B,C1!,D2%,E4@,E6$,Z$
20 DATA 2,32.9987,(83+19),-6, TRUE, CAT",'DOG'
30 PRINT A%,B,C1!,D2%,E4@,E6$,Z$
In the example above, BASIC assigns these values:
A% = 2
B = 32.9987
C1! =102
D2% =-6
E4@ = TRUE
E6$ = CAT
Z$ = DOG
READ and DATA are useful to initialize the values of variables and
arrays at the beginning of a program. To do this, place READ
statements at the beginning of the program. You can put the DATA
statements anywhere in the program. It is often useful to put them all
at the end of the program just before the END statement. See also
the RESTORE statement.
6.8.10 RESTORE Statement
The RESTORE statement is used when reading from a DATA
statement more than once. When you READ data from a series of
DATA statements, BASIC advances an internal pointer to the next
item in the data list every time a READ is done. Once you have read
all the items in the data list, this internal pointer points to the end of
the data list. If you want to read starting with the first DATA
statement, the RESTORE statement tells BASIC to reset its pointer to
the beginning of the DATA statements. The RESTORE statement has
the format:
RESTORE
or
RESTORE line_number(expression)