Kinetis Microcontrollers中的主题 Re: kl25z vlpr_lls_adc project failed to toggle LED?

kl25z vlpr_lls_adc project failed to toggle LED?

kai_liu — Fri, 09 Aug 2013 04:34:55 GMT

I tried to run the demo code from FSL (D:\Freescale\Kinetis L Sample Code\kl25_sc_rev5\klxx-sc-baremetal\build\iar\vlpr_lls_adc). The RGB LED should be toggled based upon counter of LPTMR timebase.

However LED array doesn't change at all. The hardware is all right, since the FRDM_KL25ZDemo works fine. The only differences between these demo applications is : vlpr_lls_adc uses GPIO to toggle LED, while FRDM_KL25ZDemo uses TPM to drive RGB LEDs.

Does anyone knows why?

Re: kl25z vlpr_lls_adc project failed to toggle LED?

chris_brown — Mon, 12 Aug 2013 16:32:15 GMT

Hi Kai Liu,

It looks like the data direction registers for each LED are not being configured correctly. Instead of waiting on an update, try modifying the SW_LED_Init function such that after each LED enable, the data direction port is configured for the corresponding LED. So the code should look like this:

LED0_EN;

LED0_DIR;

LED1_EN;

LED1_DIR

LED2_EN;

LED2_DIR;

LED3_EN;

LED3_DIR;

We will make sure to change this in our next sample code update.

Thanks,

Chris

Re: kl25z vlpr_lls_adc project failed to toggle LED?

kai_liu — Tue, 13 Aug 2013 08:29:53 GMT

Thanks, Chris,

It solves my issue. I found the macro definitions in freedom.h

#define LED0_DIR (GPIOB_PDDR |= (1<<18))

#define LED1_DIR (GPIOB_PDDR |= (1<<19))

#define LED2_DIR (GPIOD_PDDR |= (1<<1))

#define LED3_DIR

In SW_LED_Init()

LED0_EN; // (PORTA_PCR16 = PORT_PCR_MUX(1))

GPIOA_PDDR |= (1<<16);

LED1_EN; // (PORTA_PCR17 = PORT_PCR_MUX(1))

GPIOA_PDDR |= (1<<17);

LED2_EN; // (PORTB_PCR8 = PORT_PCR_MUX(1))

GPIOB_PDDR |= (1<<8);

LED3_EN; // (PORTA_PCR5 = PORT_PCR_MUX(1))

GPIOA_PDDR |= (1<<5);

The LED0/1/2/3 were setup as PTA16/PTA17/PTB8/PTA5. I guess it is a issue due to wrong GPIO layout due to clone source from other projects.

Yours sincerely

Allan K Liu