pluse number count

[Carey]

I need to count the pluse number use 51822, the frequency about this pluse is about  0.01Hz to 1Hz and is not fixed,  I know use Time1 can achieve this funtion,  but the problem is i need achieve it use very lower power consumption , is it possible to reduce the current until it's lower than 30uA?  How to set it is the best choise for save power. I just need use two funtion in my project: BLE advertisement and count pluse number.

[Einar Thorsrud]

Hi,

The frequency of what you want to capture is so low that I do not see any need for using a timer. You could use a RTC in counter mode, but the problem is that you would get high current consumption from using GPIOTE with PPI. I have not done the calculations, but my gut feeling is that the most power efficient way to do this is to simply use GPIOTE port event (ow accuracy mode) and wake up the CPU to increment a variable (though it might seem a bit counter intuitive).

[Carey]

thanks your advise, but i saw in the code, every GPIOTE port event wake up the CPU need reset the CPU?  so how can i save that value of variable? and if i use GPIOTE port event, how much is it the every average current?  

[Einar Thorsrud]

Where did you see that? There is no reset of the CPU when there is a port event, so this should not be a relevant concern.

(You may have seen that a GPIO pin can be used as a wake-up source from system off low power mode, which always occur as a reset. However, there is no reset as long as you don't use system off. However, system off does not make sense when you want to wake up as often as several times per second.)