Status Commands - Stanford Research Systems SR124 Operation And Service Manual

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4.4.13 Status commands

LOCK?
Example:
OVLD?
Example:
OFSL SLOPE6DB
OMOD LOCKIN
OFSE OFF
OFST 0.0
KCLK ON
ALRM ON
Lock status
Reads the current value of the reference oscillator lock status. Returns
a token, with values z (UNLOCKED 0, LOCKED 1, or NOTPLL 2).
If the SR124 reference oscillator is operating in one of the external
reference modes (FMOD EXT1F, FMOD EXT2F, or FMOD EXT3F), then
the query LOCK? will return either UNLOCKED 0 or LOCKED 1 based
on the current status.
If the SR124 reference oscillator is configured for either
FMOD INTERNAL or FMOD RVCO, then LOCK? responds with NOTPLL
2.
LOCK?
LOCKED
Overload
Reads the current value of the signal overload status. Returns an
integer between 1 and 15 if an overload is detected, or 0 if there is no
overload.
The response integer is binary-weighted based on the four (4) sepa-
rate signal stages that can generate an overload detect:
1 Preamp overload
2 Current amp overload
4 Intermediate (AC) amp overload
8 Output (DC) amp overload
For example, if the preamp and the intermediate amp are both over-
loading, OVLD? will respond with 5 ( 1
OVLD?
0
Remote Operation
4).
SR124 Analog Lock-In Amplifier