Technical reference
3.4.3More on streaming mode
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In streaming mode, the computer prompts the unit to start collecting data. The data are then transferred back to the PC without being stored in oscilloscope memory. Data can be sampled with a period between 1 millisecond and 60 seconds.
Data can be transferred by the PicoScope 2000 Series driver to a computer program in either normal or windowed mode.
Normal mode
In normal mode, any data collected since the last data transfer operation are returned in their entirety. This mode is useful if the computer program requires only fresh data on every transfer.
Windowed mode
In windowed mode, a fixed number of samples is returned, even if the oldest samples have been returned before. Windowed mode is useful when the program requires data from a constant time interval.
Notes
Once the unit is collecting data in streaming mode, any setup changes (for example, changing a channel range or AC/DC setting in the PicoScope software application) will cause a restart of the data stream.
The driver can buffer up to 32K samples of data per channel, but the user must ensure that the ps2000_get_values() function is called frequently enough to avoid buffer overrun.
The ps2000_get_times_and_values() function will always return FALSE (0) in streaming mode.
3.4.4Triggering
The unit can either start collecting data immediately, or it can be programmed to wait for a trigger event to occur. In either case, you need to use the ps2000_set_trigger() function. A trigger occurs when the input crosses a threshold voltage on either a rising or a falling edge.
3.4.5ETS (Equivalent Time Sampling)
ETS is a way of increasing the effective sample rate when working with repetitive signals. It is not possible to use ETS with
function will return FALSE (0).
3.4.6Voltage ranges
It is possible to set the gain for each channel with the ps2000_set_channel() function. This allows you to set an input voltage range between ±100 mV and ±20 V.
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