User`s guide

Table B3. OE-2 Specific Commands cont.
Command Command Syntax Query Syntax
NULLoffset :NULLoffset<Float>
Used to calibrate the OE-2 when no optical power is
present. When using a short calibration no string is
required. When using a long cal the string represents the
null offset in bits.
:NULLoffset ?
Return value: Floating point value representing the last
stored null offset of the OE-2.
AVEraging AVEraging <string>
Valid strings:
OFF – averaging off
1-40 – set number of samples averaged in firmware
AVEraging ?
returns current state of averaging
System (root
command)
ADFormat
:ADF <string>
Valid Strings:
BITS
VOLTS
:ADF ?
return a string representing the current format.
CALibrate (root
command)
CALType
:
CALType <string>
Valid strings:
0 – Short cal
1 – Long cal
SHORT – short cal
LONG – long cal
:CALType ?
return a string representing the current calibration
type.
OE-2 Specific Commands Description
CHANnel (CHANx): Root command that specifies the channel to which a subcommand applies. On a Dual Channel OE-2,
‘x’ may take on values of ‘1’ or ‘2’. On a Single Channel OE-2, ‘x’ may only take on a value of ‘1’.
ACResponse: Channel subcommand that provides a query response only. The AC response of the OE-2 Channel is
determined from the current wavelength, filter, and amplifier settings. This constant, in units of W/V, is used to
convert the electrical output of the OE-2 in volts to optical input power. When combined with the average
power reading the level and magnitude of the input optical signal can be determined. The AC Response is valid
at 100MHz. Example read: ‘:CHAN1:ACR?’.
AMPLifier: Channel subcommand that sets the amplifier for the specified channel or reads the current setting.
Valid amplifier settings are ‘10DB’, ‘20DB’, ‘30DB’, and ‘40DB’. Example write: ‘CHAN1:AMPL 20DB’.
AVEPwr: Channel subcommand that provides a query response only. The average power of the input optical signal
is returned in units of watts. Example read: ‘:CHAN1:AVEP?’.
AVEraging: Channel subcommand that specifies the amount of firmware averaging of the O/E average power
measurement. When off, an average power query retrieves the instantaneous measurement. When averaging is
on, the firmware averages some number of 40 samples taken every second. For example, for the command
“:CHAN1: AVE 10”, the firmware would average every 10 samples. An AVEP query will return the last
averaged value. When averaging is on, the number of independent readings available every second is reduced.
In the example above, the number of independent readings is reduced from 40 to 4.
APPENDIX B | GPIB Commands |
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