HP 54501A Programming Reference Manual page 96

Common Commands
5
The
common commands are defined
by
the
IEEE
488.2
standard. These
commands will be common to all
instruments that
comply with this
standard.
They control
some
of the basic instrument functions, such as
instrument identification and reset, reading the learn (instrument setup)
string, how status is read
and cleared, and how commands and
queries
are
received and processed by
the instrument.
Common commands
can be received and processed
by
the
HP 54501A
whether they are
sent
over the
HP-IB
as
separate
program messages or
within other program
messages.
If
an instrument subsystem
has been
selected and
a common command
is
received
by
the instrument, the
instrument
will remain
in the selected subsystem.
For example, if
the
program message
"ACQUIRE:COUNT 1024; *CLS; TYPE AVERAGE"
is
received
by
the instrument, the instrument will
set
the acquire count and
type, and clear the status information.
This would
not be the case
if
some
other type
of
command were received within the program message. For
example the program
message
":ACQUIRE:COUNT 1024;
:AUTOSCALE;
:ACQUIRE:TYPE AVERAGE" would
set
the acquire count, complete the
autoscale,
then
set
the acquire type.
In
this
example
:ACQUIRE
must be
sent
again in order to reenter the acquire subsystem and
set
the
type.
Refer
to figure 5-1 for common commands syntax diagram.
Note
Each of
the status
registers
mentioned
in
this chapter has an
enable (mask) register.
By
setting the bits in the enable register
you can
select
the status
information
you wish to
use.
For
a
complete discussion of
how
to read
the status registers
and how
to use
the status information available
from
this instrument refer
to chapter
3.
HP 54501A
Programming
Common Commands
5-1