Command line interface
6.6 Output configuration
6.6.1 SAMPLES/SEC
Syntax:
tap-0
tap-1
tap-2
tap-3
samples/sec
The DSP software on the DM24 supports up to 7 cascaded filter/decimation stages.
At each stage, the sample rate can be divided by a factor of 2, 4 or 5. The internal
ADC outputs data at 2000 samples per second, so decimated data streams are
available from 1,000, 500 and 400 samples/sec down to 1 sample/sec.
You can specify the sample rate to use at four of these stages, known as
taps
. You
can also take output from any of these four stages. The DM24 will arrange the
remaining stages according to your settings.
The arguments
tap-0
to
tap-3
are the sample rates at each tap in turn, starting with
the highest. You must ensure that each rate is lower than the previous one by a
factor of 2, 4, 5, 8 (= 2 then 4), 10 (= 2 then 5) or 16 (= 4 then 4). Non-integer values are
not allowed.
For example:
1000 125 25 5
samples/sec
1000 500 100 10
samples/sec
500 100 20 4
samples/sec
400 40 10 5
samples/sec
As long as you specify the initial taps, you can omit later ones. The command fills in
the value of the missing taps, using a decimation factor of 2 where possible. Thus,
the following commands are equivalent:
400 40 20 10
samples/sec
400 40
samples/sec
Note: Older DM24 software did not support the new GCF format for higher
sample rates. It also did not properly support 250 samples/s, nor rates
below 1 sample/s.
6.6.2 CONTINUOUS
Syntax:
tap
components
CONTINUOUS
Sets which components are output under normal conditions, and at which tap(s).
tap
is the tap number at which to output the triggered stream. You can set which
taps output which sample rate using the
SAMPLES/SEC
command, described above.
components
is an integer below 16, whose binary bits represent the
Z
(1),
N
(2),
E
(4)
and auxiliary (8) components respectively.
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Issue U - December, 2021
