[MKW01Z128] Radio operation with 32.768kHz xtal

[giancarlozanuz]

Hello, I'm facing some problems with the radio communication when using an external 32.768kHz crystal.

I'm using two KW01-MBR development boards and the examples from Connectivity Software. When I connect J8 (XTAL_32K jumper) to position 1 - 2 (PTA18 and DIO5/CLKOUT) and define in 'board.h' file CLOCK_INIT_CONFIG CLOCK_RUN, the program runs fine, I can send and receive messages with no problem.

But when I change to the external crystal in J8 to position 2 - 3 (PTA18 and EXTAL_32K_EXT), and define CLOCK_INIT_CONFIG CLOCK_XTAL, the program does not work well, and the radio interface does not work anymore.

Do I need to setup any other option or configuration to work with the external crystal? Thanks!

[luisburgos]

Hi Giancarlo,

You also need to change the pin multiplexing in pin_mux.c for PTA18 and PTA19.

PTA18 and PTA19 are configured as MUX1 by default, but those pins need to be configured as MUX0, as shown in reference manual:

For PTA18:

PTA19:

Best regards,

Luis Burgos.

[giancarlozanuz]

It worked, thanks!