Motor shield current - analog input A0 problem

Hi everyone,

I have Arduino Uno and motor shield R3, my analog input A0 is no function, when motor shield is connected (for sensing current), but sensor is ok (i have 0,44V on pin A0) but is still reading value 16 - 17 from 1023 on A0.

For alone arduino is input OK! I measure it for more voltages, its ok... only with motor shield is problem. Its very curious, someone for help ?

Thanks

Sounds like physical short on the shield or the pin not making contact. We get that from time to time here.

Grumpy_Mike: Sounds like physical short on the shield or the pin not making contact. We get that from time to time here.

I think all contacts must be ok. - because voltage generated from motor shield is ok and this voltage is on pin A0 and atmega pin

It is about PWM, because where I set 100% pwm high it's ok....

Can someone help?

trevor3: I think all contacts must be ok. - because voltage generated from motor shield is ok and this voltage is on pin A0 and atmega pin

That is not a logical conclusion.

It is about PWM, because where I set 100% pwm high it's ok..

So why is it not a contact problem.

Can someone help?

Well if anyone fancies being dismissed and ignored by irrelevances then by my guest.

Grumpy_Mike:

trevor3: I think all contacts must be ok. - because voltage generated from motor shield is ok and this voltage is on pin A0 and atmega pin

That is not a logical conclusion.

It is about PWM, because where I set 100% pwm high it's ok..

So why is in not a contact problem.

Can someone help?

Well if anyone fancies being dismissed and ignored by irrelevances then by my guest.

The low-pass filter between motor shield and A0 solved my problem. Thanks for ambition.