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Attention
The number of set collection points cannot exceed 2MPts.
3.2.
Signal acquisition mode
PCI-1132 data acquisition device supports the following three acquisition modes when
performing DI acquisition:
Continuous acquisition mode
Limited collection mode (OneShot mode)
Single read
The sampling rate of the first two modes adopts hardware timing.The limited number
acquisition mode is called OneShot mode.
Hardware timing
Hardware timing refers to the sampling rate of the sample acquired by DI. It is controlled
by the hardware digital signal (DI sampling clock).
Continuous acquisition mode
The continuous acquisition mode refers to continuous and uninterrupted data acquisition at
a set sampling speed.
In the continuous acquisition mode, after the DI acquisition triggers, the acquisition device
collects the signal at a fixed sampling speed, buffers it in the FIFO, and continuously
uploads the data in the FIFO to the computer memory buffer. The user program only needs
to continuously process the data in memory to achieve continuous uninterrupted data
collection.
If the user program could not process the data fast enough, the data will gradually fill up
the 2M points of storage space in the computer's memory buffer. After filling it up, the
new data cannot be written into memory buffer correctly, resulting in data discontinuity.
Limited number acquisition mode
Limited number of acquisition modes (OneShotmode) refers to one-time acquisition of the
set number of collection points at the set sampling speed.
In OneShot mode, after the DI acquisition triggers, the acquisition device will start
acquiring set number of data at the set sampling speed and stop the acquisition
automatically after. The user program only needs to read the set data amount from the
computer memory buffer.
Single read
Single read refers to reading the status of the current digital input port once. No trigger is
required for a single read.
