EXFO FVA-3150 Variable Attenuator - Manual (Page 89)

Remote Control Commands
Variable Attenuator 83
Specific commands-Quick Reference Command Tree
ATTenuation?
Description This query returns a value corresponding to the CAL parameter
value added to either the current attenuation setting, the
minimum attenuation, or the maximum attenuation setting.
Syntax ATT? [<wsp><value>]
Parameters The <value> parameter is optional and can be
“MIN” to obtain the minimum setting for the current wavelength
“MAX” to obtain the maximum setting for the current
wavelength
Response The attenuation value in the format “99.999”. The units are dB.
Note that, depending on the current measurement mode, the
response will include different parameters:
In Absolute mode:
In Reference mode:
In Offset mode:
Example ATT? MIN
Note The ATT? command is not equivalent to the INP:ATT?
command.
response actual attenuator general offset (CAL?) + =
response
actual
attenuation
reference value
INP:OFFS?  
general offset
(CAL?)
+ – =
response
actual
attenuation
wavelength-specific
offset
general offset + + =