nrf52 SAADC single ended samples GND returns 65535 indicating mode configuration errors.

I used the example code on nrf52840 DK (PCA10056) to sample GND signal in Single-Ended mode. The returned value sometimes is 65535 which indicates potential wrong configuration of the sampling mode. Maybe set still as Differential instead of Singel-Ended when configured as Single-Ended.

Please help check, test and fix this issue.

Thanks,

Start by reproducing the reported behavior with the example code on an nrf52840 DK (PCA10056), sampling GND in single-ended mode. Inspect the SAADC mode configuration and compare the returned value with the expected result; done means the configuration is correct and GND no longer intermittently returns 65535.

Written by the indexing model from the issue text.