Keithley 3700 series Reference Manual page 217

Series 3700 System Switch/Multimeter Reference Manual
dmm.autozero
Attribute
Usage
Remarks
Example
dmm.calibration.ac
Function
Usage
Document Number: 3700S-901-01 Rev. A / August 2007
Indicates the auto zero setting for the DMM.
To read the auto zero status:
value = dmm.autozero
value: Represents the present auto zero setting (1 = ON, 0 = OFF)
To change the auto zero status:
dmm.autozero = value
value: Represents the desired auto zero. Use one of the following:

dmm.ON or 1 to enable auto zero

dmm.OFF or 0 to disable auto zero

dmm.AUTOZERO_ONCE or 2 to refresh backgrounds once and go to auto zero off
setting (0 will be returned if auto zero status is read).
This is the auto zero setting for the DMM. It applies to the selected function as indicated
by dmm.func (on page 9-91). Querying the auto zero when the selected function does
not have an auto zero setting associated with it will cause nil to be returned.
An error is generated if command is received when dmm.func = "nofunction".
Also, an error will be generated if the value is invalid.
Changing functions with
setting to take effect.
The auto zero once setting will force a refresh of the backgrounds. After doing this
once, the auto zero setting will automatically be set to "OFF". Therefore, querying the
dmm.autozero state after setting dmm.autozero to 2 generates a response of 0 and not
2.
To enable auto zero for DC volts:
dmm.func = "dcvolts"
dmm.autozero = dmm.ON
To force backgrounds to cycle once and set auto zero to OFF:
dmm.autozero = dmm.AUTOZERO_ONCE
print(dmm.autozero)  0.000000000e+000
Signals the desired AC calibration step on the DMM.
dmm.calibration.ac(step, value)
step: Represents the AC calibration step to perform
value Represents the associated value for this functions step. This is an optional
parameter. Only use if calibration step has a value associated. If no value is needed,
use dmm.calibration.ac(step).
Section 9: Instrument Control Library (ICL)
dmm.func (on page 9-91) will cause that function's auto zero
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