timer adc

[bendkhilarwa]

Posted on March 10, 2016 at 23:11

hello, please I need some help.

I want to measure the frequency of a continuous current motor. then to do this I use an infrared sensor. this sensor is linked to the ADC of the STM. each time the sensor makes a round , the infrared sensor sends a signal to the microcontrollers. so I want to measure the time between two signals arriving at the adc. so how can I use the timer to count this time . 

[Tesla DeLorean]

Posted on March 11, 2016 at 01:09

Set a timer in maximal mode, and use the Input Capture mode or PWM Input mode to timestamp or time the interval?

Both method have been covered here before. You don't measure a frequency, but if you configure the timer to count at 1 MHz, you will be able time intervals to 1 microsecond. You should probably be more specific about what part you are talking about, ST makes hundreds of different parts.

[Tesla DeLorean]

Posted on March 11, 2016 at 01:11

If you have to read the ADC sample to threshold the signal, you could still use a free running maximal timer to pull time stamps for the ADC EOC, or TIM Trigger of the ADC

[bendkhilarwa]

Posted on March 11, 2016 at 02:04my problem is exactly that, I want to measure the time separing two input signals. for example, if I'm using the push button as a signal input, so I want to know the time between the first push and the second one. I have done some research about timer, I think that the capture mode, measure the width of the signal