Acqiris SA220P - Page 59

4.4 Thresholding (Zero-Suppress - ZS1 option)
Acqiris SA220P User's Manual 59
IVI-C
Attributes
AQMD3_ATTR_ACQUISITION_DATA_REDUCTION_
MODE
Defined by a repeated capability:
AQMD3_VAL_ACQUISITION_DATA_REDUCTION_MODE_
DISABLED
AQMD3_VAL_ACQUISITION_DATA_REDUCTION_MODE_
ZERO_SUPPRESS
AQMD3_ATTR_CHANNEL_ZERO_SUPPRESS_
HYSTERESIS
Specifies the hysteresis width.
AQMD3_ATTR_CHANNEL_ZERO_SUPPRESS_POST_
GATE_SAMPLES
Specifies the number of samples to be kept after gate stop con-
dition.
AQMD3_ATTR_CHANNEL_ZERO_SUPPRESS_PRE_
GATE_SAMPLES
Specifies the number of samples to be kept before gate start
condition.
AQMD3_ATTR_CHANNEL_ZERO_SUPPRESS_
THRESHOLD
In ZeroSuppress DataReduction mode, the total amount of data
recorded is reduced by eliminating samples below the level of
interest: Threshold. The value is specified as a signed left-
aligned 16-bit ADC code.
The range of accepted values is [Hysteresis-32768, +32767].
AQMD3_ATTR_CHANNEL_ZERO_SUPPRESS_ZERO_
VALUE
In ZeroSuppress DataReduction mode, the value used to
replace suppressed samples in a standard waveform construct.
It is a signed left-aligned 16-bit ADC code
Using zero-suppress with negative pulses
For some applications, the signal of interest could be negative peaks.
It is possible to select relevant signal below the defined threshold and suppress data above it, by:
1. inverting data values (using DataInversionEnable),
2. applying the zero-suppress threshold.