Agilent Technologies 8504B, User Manual

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FINAL TRIM SIZE : 7.5 in x 9.0 in
Programming
Controlling the Instrument
Send commands as
ASCII strings
Commands are sent to the precision reectometer as ASCII strings . The
method used depends on the programming language and environment. Using
an PC with the HP-IB Interface and Command Library (and programming in
C), send a command as follows:
iooutputs(716L, "PRES;", 5);
Using an HP 9000 Series 300 technical computer with the HP-B ASIC language ,
the same command would be sent as follows:
OUTPUT 716;"PRES;"
Use a semicolon (;) to terminate each input string of program commands . A
line feed can also serve as a terminator . F or example , either of the following
is acceptable .
OUTPUT 716;"PRES;CLEARALL;"
OUTPUT 716;"PRES;CLEARALL"
Returning data to the
controller
Some precision reectometer commands can be issued as a query . A query
causes data to be returned to the computer from the instrument. The data is
returned as an ASCII string. Queries are formed by adding the question mark
(?) character to the command. Refer to the command listing in this chapter
to determine if a command can be used as a query . syntax listed for each
command .
F or example , sending the following command turns the HP-IB command
debug mode on:
OUTPUT 716;"DEBUOFF;"
Upon receiving this command, the precision reectometer sends a \1" to
the computer . (A \1" indicates an \on" condition; a \0" indicates an \o"
condition.)
Querying a settable functions such as SCAL , returns the current function
value then clears the instrument entry area. Querying a command that does
not have a dened response returns a zero . The following example returns a
value to the computer and then prints the value:
OUTPUT Hp8504;"SCAL?;"
ENTER Hp8504;Scale
PRINT Scale
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