Response Header Options - HP 54501A Programming Reference Manual

Response Header
The format of
the returned
ASCII string depends on the current settings
Options
of the
SYSTEM
HEADER
and
LONGFORM
commands. The general
format
is:
<
header
> <
separator
>
<data>
< terminator >
The
header identifies the data that follows and
is controlled by issuing
a
:SYSTEM:HEADER ON/OFF
command.
If
the
state
of the header
command
is
OFF,
only
the data
is
returned
by
the
query.
The format of
the header
is
controlled
by
the
:SYSTEM:LONGFORM ON/OFF
command.
If
longform is
OFF,
the header will be in
its shortform and the
header will vary
in
length depending on
the
particular query. The
following
would be returned from
a
:MEASURE:FREQUENCY?
frequency measurement query:
< data > < terminator >
(with
HEADER
OFF)
:MEAS:FREQ
<
separator
>
<
data
> <
terminator >
(with HEADER ON/LONGFORM OFF)
:MEASURE:FREQUENCY
< separator > <
data
> <
terminator
>
(with
HEADER ON/LONGFORM ON)
Note
A
command or query may
be
sent
in either longform or
shortform,
or
in any combination
of longform and shortform.
The
HEADER
and
LONGFORM
commands only control
the
format of
the returned data and have
no effect on
the way
commands are
sent.
Common commands
never
return
a
header.
Refer
to the
chapter "System Subsystem" for information on
turning
the
HEADER
and
LONGFORM
commands on and off.
Introduction to Programming
an Oscilloscope
HP 54501A
1-14
Programming