RTC CLOCK OUT on MK22FN512VDC micro-controller

[wavhal_m]

Hello all,

I'm using MK22FN512VDC micro controller and Kinetis design studio. System clock is running on 8MHz external crystal and external 32.768KHz RTC oscillator is connected to the micro-controller. I wish to send RTC CLK32OUT on other available GPIO pin. Unfortunately on my hardware both of CLK32OUT pins are used for other components. So is it possible to send RTC clock out by using other timers like FlexTimer and by keeping RTC as a main clock source to generate timer interrupt? What will be the maximum possible toggling speed of the IO pin?

[wavhal_m]

Hello all,

I found the solution and its details are mentioned below - 

1. In the Kinetis Design Studio opened the "Processor Expert" Created new Timer Component.

2. Used LPTMR0 in counter mode, kept the Input clock source as Internal and from the settings provided selected the Clock source from ERCLK32K. Clock source to the ERCLK32K is External RTC.

3. Counter restarted on every timer tick and generated interrupt to toggle the GPIO pin on event.

However in this generated code Pin toggling is not working automatically and need to write separate in code and I'm not having other timer sources available. So any suggestions to optimise the code are appreciable.

 

[_Leo_ · Accepted solution]

Hi,

Thank you so much for your interest in our products and for using our community.

Sorry but I could not found another idea to optimize your code with the conditions that you mention. I think that the best way is to reevaluate your pin assignment and output the CLKOUT32K signal from its dedicated pins.

Sorry for the inconvenience.

Have a nice day!