Welding System User Manual

Chapter 2 Function Reference — Set_DAQ_Device_Info
NI-DAQ FRM for PC Compatibles 2-392
© National Instruments Corporation
When NI-DAQ uses DMA channels for data transfers, it must have an interrupt level available
for the device performing the transfers. In this case, NI-DAQ uses interrupts for DMA
controller reprogramming and exception handling.
Using This Function
You can use this function to select the data transfer method for a given operation on
a particular device. If you do not use this function, NI-DAQ decides on the data transfer
method that typically takes maximum advantage of available resources.
ND_NO_TRACK_AND_HOLD
Disables use of the track-and-hold circuitry on the
SC-2040
1
ND_OFF
Disables the ACK and REQ exchange or the
reversal of the clock direction of the DIO 6533
(DIO-32HS)
ND_ON
Exchanges the ACK and REQ pins or reverses the
clock direction on the DIO 6533 (DIO-32HS)
ND_STRAIN_GAUGE
Enables the SC-2043-SG accessory for
strain-gauge measurements (no excitation on
channel 0)
ND_STRAIN_GAUGE_EX0
Enables the SC-2043-SG accessory with excitation
on channel 0
ND_TRACK_AND_HOLD
Re-enables the track-and-hold circuitry on an
SC-2040 if you have previously disabled it.
2
ND_UP_TO_1_DMA_CHANNEL
NI-DAQ must use only one DMA channel; if the
DMA channel is not available, NI-DAQ reports an
error and it will not perform the operation
ND_UP_TO_2_DMA_CHANNELS
NI-DAQ uses two DMA channels, if possible;
otherwise, it uses one DMA channel, if one is
available; if no DMA channels are available,
NI-DAQ reports an error and it will not perform the
operation
ND_FOREGROUND
NI-DAQ performs data transfers through the CPU
1
You should use this setting to use the SC-2040 only as a preamplifier, without using track and
hold.
2
With
ND_NO_TRACK_AND_HOLD
.
infoValue Description