Single-Values Operations; Continuous Scan Mode - Data Translation DT9837A User Manual

Single-Values Operations

If you prefer to read a single value from all the analog input channels simultaneously using
one software call, use a single-values operation. You specify the analog input subsystem and
the gain that you want to use for the channels (not the channels themselves). The module then
acquires a value from each input channel simultaneously; the data is returned as an array of
input values.
Note: For the DT9837, a single values operation also returns a valid value from tachometer
counter 0 (analog input channel 4), described on
For the DT9837A and DT9837B, a single values operation returns values from the analog
input channels as well as from tachometer counter 0 (described on
counter 1 (described on
output readback channel (for the DT9837A; described on
analog input channels 0 through 3 is valid. Use continuous scan mode, described next, to read
valid data from the tachometer counters, gate counter, and analog output readback channel.
For single-values operations, you cannot specify a clock source, trigger source, scan mode, or
buffer. Single-values operations stop automatically when finished; you cannot stop a
single-values operation.

Continuous Scan Mode

Continuous scan mode takes full advantage of the capabilities of the DT9837 Series modules.
You can specify a channel list, clock source, start trigger, reference trigger, post-trigger scan
count, and buffer using software.
On the DT9837 module, you can enter up to 5 entries in the channel list, including four analog
input channels (A/D channel 0 to 3) and tachometer counter 0 (A/D channel 4), described on
page 82.
On the DT9837A module, you can enter up to 8 entries in the channel list, including four
analog input channels (A/D channels 0 to 3), tachometer counter 0 (A/D channel 4), described
on page 82, tachometer counter 1 (A/D channel 5), described on
channel 6), described on
described on page 79. Using software, specify the channels you want to sample in sequential
order.
On the DT9837B module, you can enter up to 7 entries in the channel list, including four
analog input channels (A/D channels 0 to 3), tachometer counter 0 (A/D channel 4), described
on page 82, tachometer counter 1 (A/D channel 5), described on
(A/D channel 6), described on
sample in sequential order.
On the DT9837C module, you can enter up to 4 entries in the channel list (analog input 0 to 3).
Using software, specify the channels you want to sample in sequential order.
page 84), gate counter 2 (described on
page 85, and the analog output readback value (A/D channel 7),
page 85. Using software, specify the channels you want to
page 82.
page 82), tachometer
page 85), and the analog
page 79), but only the data from
page 84, gate counter 2 (A/D
page 84, and gate counter 2
Principles of Operation
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