I need help with saadc.

[schosdas]

Hello

I'm using saadc sdk (v17.02) and I'm using a simple water level sensor.

I am asking a question because there is something strange about reading this sensor through saadc.

This sensor measures the height of the water and returns the analog value.  The maximum value is measured in the middle of the sensor's water height, and if the water height increases further, the sensor's value decreases.  When I measured the voltage of the sensor, I checked that the voltage changes according to the height of the water.

May I know the cause of this problem?

Thank you.

[StefXinet]

Hello,

could you post a schematic?

I suggest to put a fixed voltage on the SADC input and misure it, so you can check if the value read is correct.

Bye

[schosdas]

Hello, StefXinet
Thank you for your answers.

I solved this problem.
I connected the sensor to 5V, Gnd, and p0.03 (A0) on the board before, but now that I changed it from 5v to VDD, it seems to be working normally.

Thank you!