Reset Pin malfunction in BMD301 based custom board

[Ankush]

Hey guys,

I have designed one custom PCB based on BMD301 in which I am observing some weird behavior on RESET pin. I have connected reset pin of BMD301 i.e. P0.21 to 3.3 volt through pull up resistor of value 10k ohm. One push button is kept which gives 0 volt when pushed thereby resetting the complete board. Practically we should get following behavior,

1. when button is not pressed --> voltage at reset pin should be near to 3.3 volt with little drop across 10 k ohm resistor.
2. when switch is pressed --> voltage at reset pin should be zero with voltage drop across 10 k ohm resistor is 3.3 volt

I am getting following thing,

--> By default when switch is not pressed voltage across 10 k ohm is 1.8 volt and at reset/P0.21 pin is 1.4 volt.

I am not actually getting what is wrong with my board. Can anyone try to give me the solution of this?

[Jørgen Holmefjord]

Have you made sure that the pin is not configured as something else in your code, for instance an output?