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Model 2657A High Power System SourceMeter® Instrument Reference Manual
Section 7: TSP command reference
2657A-901-01 Rev. B/December 2012
7-183
Usage
smu
X
.cal.password =
newPassword
X
SMU channel (for example,
smua.cal.password
applies to SMU channel A)
newPassword
The new password (string)
Details
A new password can only be assigned when calibration has been unlocked.
The calibration password is write-only and cannot be read.
Example
smua.cal.password = "LetMeIn"
Assigns a new calibration password for SMU channel A.
Also see
(on page B-14)
(on page 7-186)
smuX.cal.polarity
This attribute controls which calibration constants are used for all subsequent measurements.
Type
TSP-Link accessible
Affected by
Where saved
Default value
Attribute (RW)
Yes
Instrument reset
SMU reset
SMU cal. lock
Recall setup
Not saved
0 (smuX.CAL_AUTO)
Usage
calPolarity
= smu
X
.cal.polarity
smu
X
.cal.polarity =
calPolarity
calPolarity
The polarity to use for measurements. Set to one of the following values:
0
or
smu
X
.CAL_AUTO
: Automatic polarity detection
1
or
smu
X
.CAL_POSITIVE
: Measure with positive polarity calibration constants
2
or
smu
X
.CAL_NEGATIVE
: Measure with negative polarity calibration constants
X
SMU channel (for example,
smua.cal.polarity
applies to SMU channel A)
Details
This attribute controls which polarity calibration constants are used to make all subsequent measurements. This
attribute does not affect the
smu
X
.measure.calibrate
Y
()
or
smu
X
.source.calibrate
Y
()
commands.
The polarity for those commands is dictated by the range parameter that is given to the command. The
measurement calibration commands require the measurements provided to have been made using the polarity
being calibrated.
When making measurements for calibration points far away from zero, the desired polarity constants are
inherently used. However, when making measurements near zero, it is possible that the instrument could use the
calibration constants from the wrong polarity. Setting
smu
X
.cal.polarity
to positive or negative forces
measurements to be made using the calibration constants for a given polarity, rather than basing the choice on
the raw measurement data.
This attribute can only be set to positive or negative when calibration is unlocked. This attribute will automatically
be set to
smu
X
.CAL_AUTO
when calibration is locked.
Summary of Contents for 2657A
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