Keysight Technologies 3458A Guide D'utilisation page 114

3 Configuring for Measurements
Autostart subprogram
When you entitle a subprogram 0, that subprogram will be executed whenever the
multimeter completes its power-on sequence or it is reset using the front panel
Reset key. This is particularly useful to automatically return the multimeter to its
previous state following a power failure. Whenever a power failure is detected, the
multimeter stores its present state as state 0 (states are discussed later in this
chapter). The following program stores an autostart program that returns the
multimeter to its power-down state and also sets the A/D converter's reference
frequency to the exact power line frequency (see
frequency
10 OUTPUT 722; "SUB 0"
20 OUTPUT 722;"RSTATE 0"
30 OUTPUT 722;"LFREQ LINE"
40 OUTPUT 722; "SUBEND"
50 END
You can also call the autostart subprogram (CALL 0 command) if you need to
execute the subprogram without having to cycle the multimeter's power.
Compressing subprograms
When you store a subprogram, the multimeter stores the ASCII text in continuous
memory and a compiled version of the subprogram in volatile memory. When you
call a subprogram, the multimeter executes the compiled version (this is why a
subprogram executes faster than the equivalent commands sent over the bus).
When power is removed, only the ASCII text is saved. When power is reapplied,
the multimeter uses the ASCII text to generate a compiled subprogram. You can
compress subprograms using the COMPRESS command. Compressing a
subprogram removes the ASCII text from continuous memory leaving only the
compiled version in volatile memory. This makes more continuous memory space
available but removes the subprogram from continuous memory (all record of the
subprogram will be destroyed when power is removed or the front panel Reset key
is pressed). The following program statement compresses the previously stored
subprogram named DCCUR1.
OUTPUT 722; "COMPRESS DCCUR1"
114
earlier in this chapter for details).
Changing the reference
Keysight 3458A User's Guide