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4. Stop: stop condition of the data acquisition
−
Automatic: when the block is full
−
Trigger: with a channel, with a combination of analog and logic channels (see chapter 5)
−
Trigger mode: Double Trigger; see the following chapter.
5. Real time save: simultaneous record of the data acquisition into a file
−
directory and name of the saving file
−
maximum length of the file
6. After acquisition: action after the end of the print; only possible if the start and stop triggers are not Manual
−
Stop: no action
−
Relaunch: waiting for the start trigger
−
Save to a file: Saving or not the data acquisition into a file
7. View of the active channels, of the recording time, of the pre-trigger
…
Pre-trigger
definition of the position of the Start trigger in the data acquisition - data acquisition before and
after trigger (before or after Start), and disabling of the trigger.
«
Impossible
» shows up when there is not enough place for saving data: you should reduce the sampling rate
or the number of channels
See chapter
File mode
to know the restrictions of the recording on file.
7.2 Sampling period
When the frequency of the input signals is too high to record them in Direct mode, you must record the measurement
signals into memory at high sampling rate: it is the
Memory mode
.
Sampling consists in recording the instant value of a signal at regular intervals and storing each of these values into a
memory.
To get adequate acquisition of a periodic signal, you need to choose a sampling period compatible with the frequency of
the signals present at the input terminals of the recorder.
A 10-dot per signal period definition is minimal for a satisfactory plot.
7.3 Internal memory, blocks
The available memory in the recorder can be shared into blocks that will be filled one after the other at each data
acquisition.
The acquisition depth is worth N / (B * V)
N= total memory amount
B = number of blocks
V = number of channels to scan
Example: memory 32 Mwords, 16 blocks and 3 channels ’ON’, we shall have: N = 32 554 432 / (16 * 3)= 699 050
words/channel.
Any new data acquisition goes automatically into the first free block (in increasing order).
