LPUART XTAL frdm KL03z

ramonramirez — Tue, 19 Sep 2017 21:36:56 GMT

I am working with the frdmKL03Z and the example lpuart_polling in the SDK 2.2 in that example use the internal oscilator but i need more Precision in the count of time

add a xtal but i think i need make changes in the software to the LPUART works well

someone can tell me if i am right ?

what change needed?

best regards

Re: LPUART XTAL frdm KL03z

mjbcswitzerland — Wed, 20 Sep 2017 00:29:01 GMT

Hi Ramon

To clock the KL03 LPUART from the XTAL you need to set

SIM_SOPT2 |= (SIM_SOPT2_UART0SRC_OSCERCLK);

so that the OSCERCLK is connected to it.

Before that, you also need to enable the oscillator:

OSC0_CR = (OSC_CR_ERCLKEN | OSC_CR_EREFSTEN); // enable the oscillator and allow it to continue oscillating in stop mode

The crystal will need to have a frequency that is suitable for the Baud rate generation - eg, the 32kHz on the FRDM-KL03Z is not because it is too slow.

Regards

Mark

http://www.utasker.com/kinetis/FRDM-KL03Z.html

Kinetis Microcontrollers中的主题 LPUART XTAL frdm KL03z

LPUART XTAL frdm KL03z

Re: LPUART XTAL frdm KL03z