HP 8920B, Руководство программиста

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Chapter 7, IBASIC Controller
PROGram Subsystem
For simple string variables the value is returned as a quoted string (“This is an
example.”). For string arrays the values are returned as a comma separated list of
quoted strings (“This is an example.”,“This is an example.”). The string array
elements are returned in ascending order (Array$(0), Array$(1), Array$(2), etc.).
If an attempt is made to query the value of a string variable or array and no IBASIC
program is in the Test Set an
IBASIC Error: -283 Illegal variable name
is
generated. If an attempt is made to query the value of a string variable or array and
the string variable specified in <varname> does not exist in the program an
IBASIC
Error: -283 Illegal variable name
is generated.
Syntax
PROGram[:SELected]:STRing? <varname>
NOTE: The program commands and syntax used to enter string data from the Test Set into the external
controller will depend upon the programming language used in the external controller. The
examples which follow represent the capabilities of HP Rocky Mountain BASIC programming
language running on an HP 9000/300 Series Controller.
Example of querying the value of a simple string variable
OUTPUT 714;"PROGram:SELected:STRing? Variable"
ENTER 714;Value$
or
OUTPUT 714;"PROG:STR? Variable"
ENTER 714;Value$
Example of querying the value of a string array with 3 elements of 5 characters each, such
as Array$(2)[5]
OUTPUT 714;"PROGram:SELected:STRing? Array"
ENTER 714 USING "3(X,5A,2X)";Result_array$(*)
or
OUTPUT 714;"PROG:STR? Array"
ENTER 714 USING "3(X,5A,2X)";Result_array$(*)
This example assumes that the string array named Result_array$(*) is dimensioned exactly the
same as the array named Array in the IBASIC program and that each element in the string ar-
ray Array has five characters in it.