User manual

Programmer’s Guide Page 24 of 66
To set the external trigger range for a DC271-FAMILY, a 10-bit-FAMILY, or a U1071A-FAMILY module, or
an AP240/AP235 signal analyzer platform, add a call to AcqrsD1_configVertical with channel = -1 before the
call to AcqrsD1_configTrigSource.
The 10-bit-FAMILY & U1071A-FAMILY dual source pattern triggers can be activated by calling the function
AcqrsD1_configTrigClass with an appropriate TrigClass and a sourcePattern indicating the two desired
sources.
3.4. Configuring Averagers
3.4.1. Basic configuration
The averagers have 2 operational modes, digitizer and averager, controlled with the function:
AcqrsD1_configMode(instrID, mode, 0, 0);
The value mode can be set to 0 (digitizer) or 2 (averager).
The averager mode uses a number of additional configuration parameters, which describe the requested averaging
conditions.
Use the following short code fragment to configure an average of 1000 waveforms of 20‟000 data points, with a
dithering range of 15 ADC LSB‟s and a start delay of 128 samples for an AP100:
AcqrsD1_configAvgConfig(instrID, channelNbr,
"NbrSamples", &nbrSamples);
AcqrsD1_configAvgConfig(instrID, channelNbr,
"NbrWaveforms", &nbrWaveForms);
AcqrsD1_configAvgConfig(instrID, channelNbr,
"DitherRange", &ditherRange);
AcqrsD1_configAvgConfig(instrID, channelNbr,
"TrigResync", &trigResync);
AcqrsD1_configAvgConfig(instrID, channelNbr,
"StartDelay", &startDelay);
AcqrsD1_configAvgConfig(instrID, channelNbr,
"StopDelay", &stopDelay);
Comments:
The value channelNbr is usually 0. However, for multi-channel Signal Analyzer platforms (AP240/AP235,
U1084A) it can take on the value of the desired channel for some of the parameters.
When in averager mode, the following digitizer parameters are ignored:
 delayTime of the function AcqrsD1_configHorizontal is replaced by “StartDelay” and “StopDelay”
 nbrSamples and nbrSegments of the function AcqrsD1_configMemory are replaced by “NbrSamples”
and “NbrSegments”
For the AP family of averagers, the values nbrSamples, startDelay and stopDelay must be integer multiples
of the „averaging block size‟, which is always 16 in the AP100 or AP240/AP235 Dual-channel mode, and
32 in the AP200 or AP240/AP235 Single-channel mode. If the supplied value is not an integer multiple of
the „averaging block size‟, it is truncated to the next lower integer multiple. Thus, nbrSamples = 250 will be
truncated to 240 (15 * 16) on an AP100, and to 224 (7 * 32) on an AP200. You can query the actual value
with the function AcqrsD1_getAvgConfig.
• For the U1084A Averager, the values startDelay and stopDelay must be integer multiples of the
„averaging block size‟, which is 16 in Dual-channel mode, and 32 in Single-channel mode. The value
nbrSamples must be a multiple of 256 in Dual-channel mode or 512 in Single-channel mode. You can query
the actual value with the function AcqrsD1_getAvgConfig