prog.book : chapter1.fm 68 Mon Feb 15 09:24:37 1999
Power Meter Remote Operation
Getting the Best Speed Performance
1-68
HP E4418B/E4419B Programming Guide
For example, with a filter length of 4 and
SENS:SPE
set to
20
,
approximately 5 readings/sec will be calculated by the power meter.
In general, free run mode will provide the best speed performance from
the power meter (especially in 200 readings/sec mode).
Output Format
The power meter has two output formats for measurement results:
ASCii
and
REAL
. These formats can be selected using the
FORMat
command.
When
FORMat
is set to
REAL
, the result returned is in IEEE 754
floating-point format (note that the byte order can be changed using
FORMat:BORDer
).
The
REAL
format is likely to be required only for 200 readings/sec mode as
a means to reduce bus traffic.
Units
The power meter can output results in either linear or log units. The
internal units are linear and therefore optimal performance will be
acheived when the results output are also in linear units (since the
overhead of performing a log function is removed).
Command Used
In free run trigger mode,
FETC?
must be used to retrieve a result.
In other trigger modes, there are a number of commands which can be
used, for example,
MEAS?, READ?, FETC?
Note that the
MEAS?
and
READ?
commands are compound commands i.e., they perform a
combination of other lower level commands. In general, the best speed
performance will be achieved using the low level commands directly.
200 Readings/Sec
In the highest speed setting, the limiting factor tends to be the speed of
the controller being used to retrieve results from the power meter and to a
certain extent the volume of HP-IB traffic. The latter can be reduced using
the
FORMat REAL
command to return results in binary format. The
former is a combination of two factors:
Содержание E4418B
Страница 22: ...prog book progLOF doc 12 Mon Feb 15 09 24 37 1999 Contents 12 HP E4418B E4419B Programming Guide ...
Страница 24: ...prog book progLOT doc 14 Mon Feb 15 09 24 37 1999 Contents 14 HP E4418B E4419B Programming Guide ...
Страница 25: ...prog book chapter1 fm 1 Mon Feb 15 09 24 37 1999 1 Power Meter Remote Operation ...
Страница 138: ...prog book ch2meas fm 1 Mon Feb 15 09 24 37 1999 2 MEASurement Instructions ...
Страница 200: ...prog book ch3calc fm 1 Mon Feb 15 09 24 37 1999 3 CALCulate Subsystem ...
Страница 228: ...prog book ch4cal fm 1 Mon Feb 15 09 24 37 1999 4 CALibration Subsystem ...
Страница 242: ...prog book ch5disp fm 1 Mon Feb 15 09 24 37 1999 5 DISPlay Subsystem ...
Страница 260: ...prog book ch6form fm 1 Mon Feb 15 09 24 37 1999 6 FORMat Subsystem ...
Страница 264: ...prog book ch7mem fm 1 Mon Feb 15 09 24 37 1999 7 MEMory Subsystem ...
Страница 294: ...prog book ch8out fm 1 Mon Feb 15 09 24 37 1999 8 OUTput Subsystem ...
Страница 302: ...prog book ch9sens fm 1 Mon Feb 15 09 24 37 1999 9 SENSe Subsystem ...
Страница 360: ...prog book ch10stat fm 1 Mon Feb 15 09 24 37 1999 10 STATus Subsystem ...
Страница 384: ...prog book ch11syst fm 1 Mon Feb 15 09 24 37 1999 11 SYSTem Subsystem ...
Страница 420: ...prog book ch12trig fm 1 Mon Feb 15 09 24 37 1999 12 TRIGger Subsystem ...
Страница 434: ...prog book ch13unit fm 1 Mon Feb 15 09 24 37 1999 13 UNIT Subsystem ...
Страница 442: ...prog book ch14serv fm 1 Mon Feb 15 09 24 37 1999 14 SERVice Subsystem ...
Страница 452: ...prog book ch15ieee fm 1 Mon Feb 15 09 24 37 1999 15 IEEE488 2 Command Reference ...
Страница 481: ...prog book progIX doc 6 Mon Feb 15 09 24 37 1999 Index 6 HP E4418B E4419B Programming Guide ...