Dataman 770 Series - Manual (Page 8)

Development kit for DATAMAN 770 series
Programmer’s Guide
2.4. Acquired data allocation
The array that is passed as the first parameter of the GetData function must be at least
1048576 items long. Acquired data will be written in the array like this:
0 1048575 1048576 - MS 1048576 - AT 1048576 - lng
Fig. 2.4.1. – Data allocation in the array
S is the memory size, AT is the amount of samples acquired after trigger, lng is the
2.5. Measurement in the sampling mode
The DATAMAN 774 oscilloscope samples at 100MS/s in real time. To achieve a
2.5.1. Random sampling method
The sampling technology is applicable to periodical waveforms only. It is also known
M
amount of received data (second parameter of the GetData function). If the
AT+HoldOff >= MS, MS equals to lng.
higher sampling speed a random sampling method is used.
as “random sampling” or “equivalent sampling”. It uses the fact, that the sampled
waveform is repeated periodically and the sampling clock is asynchronous in relation
to the waveform. The principle is shown on the figure 2.5.1.1. The sampled waveform
with triangular shape is sampled with the rising edge of the sampling clock.
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