SWCU192 November 2021 CC1312R7 , CC1352P7 , CC2652P7 , CC2652R7
A capture request signal can be routed from RFCORE to trigger samplestamp capture. The EVENT:I2SSTMPSEL0 register selects the RFCORE signal to be used. Whenever this capture request signal is high:
Also, on the first WCLK edge of each frame, the current value of I2S:STMPXCNT is captured in I2S:STMPXPER, and I2S:STMPXCNT then restarts counting from 0.
Using these values, a fixed-point samplestamp value can be calculated:
I2S:STMPWCNTCAPT0 + (I2S:STMPXCNTCAPT0 / I2S:STMPXPER)
Notice that the value of I2S:STMPXPER will not normally be captured at the same time as the other values. Therefore, I2S:STMPXPER can be less than I2S:STMPXCNTCAPT0.