Measurement Computing Data Translation DT3010 Series, User Manual, Page: 128 / 232

Principles of Operation
127
Waveform Generation
Use waveform generation mode if you want to output waveforms repetitively.
Before this process can begin, the host computer must transfer the entire waveform pattern to
output to the DACs from a single buffer allocated in computer memory into the output FIFO
on the board. Use software to allocate a single buffer and to specify the waveform pattern.
For the DT3010, DT3010-268, and DT3016 boards, if you are using a single DAC, the waveform
pattern can range from 2 to 4,096 samples; if you are using two DACs, the waveform pattern
can range from 2 to 2,048 samples. For the DT3010/32 and DT3010/32-268 boards, if you are
using a single DAC, the waveform pattern can range from 2 to 32,768 samples; if you are using
two DACs, the waveform pattern can range from 2 to 16,384 samples. Specify both DACs in
the analog output channel list.
When it detects a trigger, the board cycles through the analog output channel list, converting
and outputting the specified waveform for the specified DACs. When the output FIFO
empties, the board issues a retransmit pulse to the output FIFO. This allows the board to
output the same pattern continuously to the DACs without having to reload the output FIFOs.
The buffer wrap mode must be single in this mode; refer to
page 127 for more information on
buffers.
The conversion rate is determined by the frequency of the D/A output clock. For DT3010,
DT3010-268, DT3010/32, and DT3010/32-268 boards, the maximum throughput rate in this
mode is 500 kHz (500 kSamples/s) in 100 mV steps or 200 kHz (200 kSamples/s) in full-scale
steps. For DT3016 boards, the maximum throughput rate in this mode is 200 kHz
(200 kSamples/s) in 100 mV steps or 100 kHz (100 kSamples/s) in full-scale steps. Refer to
page 123 for more information on the D/A output clock.
To select waveform generation mode, use software to specify the following parameters:
• Set the dataflow to Continuous.
• Set WrapSingleBuffer to True to use a single buffer.
• Set the trigger source to any of the supported trigger sources. Refer to page 124 for more
information on the supported trigger sources.
Data Format and Transfer
Data from the host computer must use offset binary data encoding for analog output signals,
such as 000 (for 12-bit boards) or 0000 (for 16-bit boards) to represent
−
10 V, and FFFh (for
12-bit boards) or FFFFh (for 16-bit boards) to rep10 V. Using software, specify the data
encoding as binary.
The host computer transfers data as 32-bit words from one or more allocated circular buffers
in computer memory to the output FIFO on the board. DT3010 Series boards act as PCI slaves
to the host computer when performing analog output operations.