Programming instructions

Measurement Operations & Settings Signal Conditioning
166 Agilent 8163A/B, 8164A/B & 8166A/B Mainframes, Fifth Edition
TIP: You can use INPut commands without a slot number if the
81560A/1A/6A/7A module is hosted by Slot 1. An INPut command is
applied to Slot 1 by default.
Command Semantic
All the INPut and OUTPut commands applicable to the 8156A attenuator
are also supported by the 81560A/1A/6A/7A modular attenuator family.
In addition, the 81560A/1A/6A/7A modular attenuator family supports
new commands to access its new features. To support these new features,
and improve the usability of the instrument, the meaning (the semantic) of
some existing commands has changed. This section lists all commands
already available to the 8156A attenuator, notes whether the semantic of
the command has changed, and where applicable, suggests how to handle
the change.
Table 7 Comparison of command semantics beween 8156A attenuator and 8156xA modular attenuator family.
Command Comment
INPut:ATTenuation
No change.
INPut:ATTenuation?
No change.
INPut:LCMode
No longer supported. Use the wavelength dependent offset command.
INPut:LCMode?
No longer supported. Use the wavelength dependent offset command.
INPut:OFFSet
No change.
INPut:OFFSet?
No change.
INPut:OFFSet:DISPlay
No change.
INPut:WAVelength
No change.
OUTPut:APMode
The 8156A uses this command to calculate a base power level while the instru-
ment switches to another mode. This behavior is replaced by a mechanism that
is easier to use.
To calculate a power level at the device under test, formerly known as through
power, the 81560A and 81561A attenuator modules use a reference power. This
reference power can be modified either via the user interface or by using the
SCPI command OUTPut:POWer:REFerence. The power is calculated from the at-
tenuation and the reference power using this formula:
P
set
(dBm) = P
ref
(dBm) - α (dB)
The 81566A and 81567A attenuator modules do not need a base power level be-
cause they are able to measure the output power directly.
Despite these new features, the 8156x modular attenuator family supports this
command, but only to address compatibility issues. The command only sets an
internal flag, which can be read using OUTput:APMode? You are free to choose
between adjusting the output power or adjusting the attenuation factor.