libiio Trigger-less mode

Question

Hello, I am trying to use the libiio library to read data from an IMU (I am not experienced with the libiio library). I specifically want to read the buffer of the accelerometer of the IMU. However, the accelerometer does not offer any setting options for a trigger (no trigger available and no trigger file in the accelerometer directory). If I use the program iio_generic_buffer, the readout only works with the trigger-less-mode, i.e. options -A -g -c -1 . If I now use the program iio_readdev with the following options, iio_readdev -s 30 -b 256 iio::device1 I run into an error. Error: WARNING: High-speed mode not enabled
ERROR: Error during buffer disable: Invalid argument

How can I avoid this error and what do I have to consider to fix this? 
 Is it even possible to read the buffer with libiio without a trigger? 
 And is it possible to read the device with the libiio library at all? If yes, could you show me an example. 
 And what does trigger less mode mean, I cannot find anything about this topic

Thanks you in advance!

Iggmercano · Accepted Answer

Hi Hmmm , 
 May I ask what MUI you are currently using? 
 As for the questions you've asked:

The warning stems from the accelerometer lacking a trigger, hindering high-speed reading. The iio_readdev error results from an incongruity between the anticipated trigger value and the accelerometer's trigger-less configuration, leading to an "argument invalid" error.

Yes, achieving the described functionality is viable. For a more in-depth understanding, please consult the documentation for ii_reg available at iio_reg Analog Devices Wiki.

Yes, iio_readdev offers a solution for such tasks. You can find a detailed example at iio_readdev Analog Devices Wiki.

In essence, the trigger-less mode results in manual data retrieval that is done by the driver. In this mode, the driver independently retrieves data (x number of samples) without awaiting a trigger.)