When using the SDK a callback shall be registered to get informed during a inventory scan when TAGs are found. Each found TAG has timestamp information relative to the start of the scan. The marked information in the screenshot are based on exact this information.
Further details about the implementation of the callback function and calculation of the read-rate can be found in the STUHFL SDK sample source code demo.
The file .\Applications\STUHFL_demo\STUHFL_demo\STUHFL_demoInventoryRunner.c shows howto configure the ST25RU3993 based EVAL/HPEV board and start the inventory scan process and howto process the cyclic replied information about found TAGs in the above mentioned callback.
The latest SDK can be found at
STSW-ST25RU-SDK - Software Development Kit for ST25RU3993 based evaluation boards - STMicroelectronics
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