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Section 9
:
Instrument Control Library (ICL)
Series 3700 System Switch/Multimeter Reference Manual
9-88
Document Number: 3700S-901-01 Rev. A / August 2007
dmm.filter.type
Attribute
Indicates the filter type for the DMM measurements on selected DMM functions.
Usage
To read the filter type:
value = dmm.filter.type
value
: Represents the present filter type setting
To write the filter type:
dmm.filter.type = value
value
: Represents the desired filter type for measurements. Use
dmm.FILTER_MOVING_AVG or 0 for moving average filter. Use
dmm.FILTER_REPEAT_AVG or 1 for repeat filtering.
Remarks
This is the filter type setting for the DMM and it applies to the selected function as
indicated by
dmm.func
(on page 9-91). Querying the setting when the selected function
does not support it will cause nil to be returned.
There are two averaging filter types to choose from: Repeating and moving. For the
repeating (which is power-on default), the stack (filter count) is filled, and the conversions
are averaged to yield a reading. The stack is then cleared, and the process starts over.
The moving average filter uses a first-in, first-out stack. When the stack (filter count)
becomes full, the measurement conversions are averaged, yielding a reading. For each
subsequent conversion placed into the stack, the oldest conversion is discarded. The
stack is re-averaged, yielding a new reading.
The command will generate an error when dmm.func = ―frequency‖, ―period‖, ―continuity‖
or ―nofunction‖. Also, an error will be generated if the value is invalid.
Changing functions with
dmm.func
(on page 9-91) has no effect on this setting.
The
dmm.reset
(on page 9-112) function selects the repeat filter.
Also see
dmm.filter.count
(on page 9-86),
dmm.filter.enable
(on page 9-87),
dmm.filter.window
(on
page 9-88)
Example
To set the filter type for two-wire ohms to moving average:
dmm.func = "twowireohms"
dmm.filter.type = dmm.FILTER_MOVING_AVG
dmm.filter.window
Attribute
Indicates the filter window for the DMM measurements
Usage
To read the filter window:
value = dmm.filter.window
value
: Represents the present filter window setting
To write the filter window:
dmm.filter.window = value
value
: Represents the desired filter window for measurements. Use a value between 0
and 10 to indicate percent of range.