why saadc values are changed on different compare time?

[wan]

Hello!

I tried to check the saadc value by using sample that is provided nordic homepage, and I just found that the saadc values changed when I changed the compare time. I'd like to check the saadc value more frequently. I think, the input voltage is same so, the value will be same. I do not know why it is changed. if you know, please help me!

[Jørgen Holmefjord]

Hi,

Did you connect analog input pin 0 (P0.02 GPIO) to anything? I see the same difference you do if I leave the pin unconnected, but if I connect it to VDD or GND I get correct values for both 400 ms and 2 ms.

Best regards,

Jørgen

[wan]

thank for advice. I put a sensor to pin 0. and detected voltage is almost same.( I'm not remember the voltage value, unfortunately.) could you check middle value to pin 0? not a edge value like VDD or GND

[Jørgen Holmefjord]

I checked middle value as well now, still get same value for 2 ms as 400 ms.