VTI Instruments EX1629, Руководство пользователя

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VTI Instruments Corp.
78 EX1629 Programming
status = vtex1629_set_lxi_limit_event_latch(vi, 0x01);
if(status < VI_SUCCESS){
<inform the user the API call failed>
}
Lead Wire Compensation
The user can also use the EX1629 to compensate for lead wire for lead wire resistance. This is a
common source of error when making measurements and can be difficult to quantify for large
channel count applications. This work can be simplified by utilizing the EX1629s
vtex1629_measure_lead_wire_resistance function.
Sample Code
ViChar errMessage[256];
ViInt32 numberOfChannels = MAX_NUMBER_OF_CHANNELS;
ViInt32 channels[MAX_NUMBER_OF_CHANNELS];
ViReal64 resistance[MAX_NUMBER_OF_CHANNELS];
ViInt32 sampleCount = 100;
int i = 0;
for(i = 0; i < numberOfChannels; i++) {
channels[i] = i;
}
memset(resistance, 0x00, sizeof(resistance));
status = vtex1629_measure_lead_wire_resistance(instrumentHandle,
numberOfChannels,
channels,
resistance,
sampleCount,
VI_TRUE);
if(status < VI_SUCCESS){
<inform the user the API call failed>
}
C
ONFIGURE
T
RIGGER AND
ADC C
LOCK
The EX1629 supports two general use-cases: standalone (one or more instruments that sample
independently and asynchronously) and master/slave (one master instrument and one or more
slave instruments, sampling synchronously). While the configurations for these two use cases are
similar, the master/slave configuration is slightly more complicated, due to the additional
requirements for distributing clock and synchronization signals to guarantee synchronous, phase-
aligned acquisition.
ADC Sample Clock
The sample clock configuration options on a standalone device and a master device are very
similar. In each case, the device is configured as a sample clock master and the internal oscillator
is used as the clock source. This sample clock can be distributed within the device and to other
devices using any of the LXI Trigger Bus lines. In the case of a standalone device, the internal
sample clock line can be also used to distribute the clock without the need to use one of the
general-purpose trigger bus lines. This internal sample clock line cannot be used in multi-box
configurations since its distribution is limited to within one device.