Different freedom board issue

[seanwu]

Dear Sir,

   I have two freedom boards. The chip number one is MKL25Z128VLK4_0N97F, and the other is MKL25Z128FRDM_1N97F.

I am not sure what the difference is between with them. Because I tried the hid_keyboard example in Freescale USB Stack v4.0.3,

using MKL25Z128VLK4_0N97F, the HID keyboard device could show in my PC, but using MKL25Z128FRDM_1N97F could not.

 

I found it always in the loop

    while((MCG_S & MCG_S_IREFST_MASK) != 0x00U) { /* Check that the source of the FLL reference clock is the external reference clock. */

    }

It seems to mean that MKL25Z128FRDM_1N97F doesn't select external reference clock.

IREFST bit in MCG Status Register (MCG_S) is not 0, and CLKST bits is not 10.

But MKL25Z128VLK4_0N97F is normal.

Could you please help me to resolve this issue?

Thanks.

BR,

Sean

[santiago_gonzal · Accepted solution]

Hello,

Your issue is because in one of your boards R25 is populated, and in the other no.

You can find the solution here:

http://mcuoneclipse.com/2012/10/27/using-the-8-mhz-crystal-on-the-frdm-kl25z-freedom-board/

Regards,

Santiago

[seanwu]

Dear Sir,

Thanks for your help.

BR,

Sean