GPIO Config in K21D50

[jitheshar]

Hi all,

     I'm new to Freescale microcontrollers. I'm now using TWR-K21D50 board for one of my project. Initially i'm triying to control GPIO pins. I have to glow the D5 led connected to the PTD4 pin. I have put my code below. But not working.

void main(void)

{

    SIM_SCGC5 |= SIM_SCGC5_PORTD_MASK; // enabled clock for the portd

    PORTD_PCR4 = PORT_PCR_MUX(1); //selected gpio functionality for pin

    GPIOD_PDDR = GPIO_PDDR_PDD(4); //put as output pin configuration

    GPIOD_PCOR = GPIO_PCOR_PTCO(4); // to make my pin low to glow the led (anode connected to 3.3v and cathode to GPIO Pin)

    while(1){

    }

}

Please help me to diagnose the problem in my code.

[jitheshar · Accepted solution]

moving the values directly to the registers without using the defined macros does the work for me.

may be macros are for different purposes.

Also in the headder i can find mask and shift values. what these shift values are used for??

[jitheshar]

thanks for your reply.

Changing GPIOD_PDDR = GPIO_PDDR_PDD(4); to GPIOD_PDDR = GPIO_PDDR_PDD(0x10); and GPIOD_PCOR = GPIO_PCOR_PTCO(4); to GPIOD_PCOR = 0x00000010u; worked for me..

Looking into register section in debugging helped me.

[carlos_chavez]

Hi Jitesh,

I know how it is when working on new microcontrollers.  I am not at my desk right now, but here is an example that I was able to quickly find from the sample code.

I hope that it helps.

BR,

Carlos

/*

* File:        gpio.c

* Purpose:        LED and Switch Example

*

*                      Configures GPIO for the LED and push buttons on the TWR-K21D50M

*                      Blue LED - On

*                      Green LED - Toggles on/off

*                      Orange LED - On if SW2 pressed

*                      Yellow LED - On if SW1 pressed

*

*                      Also configures push buttons for falling IRQ's. ISR

*                        configured in vector table in isr.h

*

*/

#define GPIO_PIN_MASK            0x1Fu

#define GPIO_PIN(x)              (((1)<<(x & GPIO_PIN_MASK)))

#include "common.h"

#include "lptmr.h"

//Function declarations

void portd_isr(void);

void porte_isr(void);

void init_gpio(void);

/********************************************************************/

int main (void)

{

  printf("TWR-K21D50M GPIO Example!\n");

  /* Turn on all port clocks */

  SIM_SCGC5 = SIM_SCGC5_PORTA_MASK | SIM_SCGC5_PORTB_MASK | SIM_SCGC5_PORTC_MASK | SIM_SCGC5_PORTD_MASK | SIM_SCGC5_PORTE_MASK;

  /* Enable GPIOC interrupts in NVIC */

  enable_irq(61); //GPIOC Vector is 77. IRQ# is 77-16=61

  /* Initialize GPIO on TWR-K70F120M */

  init_gpio();

  while(1)

  {

    //Set PTD4 to 0 (turns on green LED)

    GPIOD_PDOR&=~GPIO_PDOR_PDO(GPIO_PIN(4));

    //Toggle the yellow LED on PTD5

    GPIOD_PTOR|=GPIO_PDOR_PDO(GPIO_PIN(5));

    //Look at status of SW1 on PTC6

    if((GPIOC_PDIR & GPIO_PDIR_PDI(GPIO_PIN(6)))==0) //if pressed...

    {

      GPIOD_PDOR&=~GPIO_PDOR_PDO(GPIO_PIN(6)); //Set PTA28 to 0 (turns on orange LED)

    }

    else //else if SW1 not pressed...

    {

      GPIOD_PDOR|=GPIO_PDOR_PDO(GPIO_PIN(6)); //Set PTA28 to 1 (turns off orange LED)

    }

    //Look at status of SW2 on PTE26

    if((GPIOC_PDIR & GPIO_PDIR_PDI(GPIO_PIN(7)))==0)  //If pressed...

    {

      GPIOD_PDOR&=~GPIO_PIN(7); //Set PTA11 to 0 (turns on blue LED)

    }

    else //else if SW2 not pressed...

    {

      GPIOD_PDOR|=GPIO_PIN(7); //Set PTA11 to 1 ((turns off blue LED)

    }

    time_delay_ms(500);

  }

}

/*

* Initialize GPIO for Tower switches and LED's

*

*   PTC6 - SW3

*   PTC7 - SW2

*

*   PTD4 - Green (D5)

*   PTD5 - Yellow (D6)

*   PTD6 - Orange (D8)

*   PTD7 - Blue (D9)

*

*/

void init_gpio()

{

  //Set PTC6 and PTC7 (connected to SW1 and SW2) for GPIO functionality, falling IRQ,

  //   and to use internal pull-ups. (pin defaults to input state)

  PORTC_PCR6=PORT_PCR_MUX(1)|PORT_PCR_IRQC(0xA)|PORT_PCR_PE_MASK|PORT_PCR_PS_MASK;

  PORTC_PCR7=PORT_PCR_MUX(1)|PORT_PCR_IRQC(0xA)|PORT_PCR_PE_MASK|PORT_PCR_PS_MASK;

  //Set PTD4, PTD5, PTD6, and PTD7 (connected to LED's) for GPIO functionality

  PORTD_PCR4=(0|PORT_PCR_MUX(1));

  PORTD_PCR5=(0|PORT_PCR_MUX(1));

  PORTD_PCR6=(0|PORT_PCR_MUX(1));

  PORTD_PCR7=(0|PORT_PCR_MUX(1));

  //Change PTD4, PTD5, PTD6, and PTD7 to outputs

  GPIOD_PDDR=GPIO_PDDR_PDD(GPIO_PIN(4) | GPIO_PIN(5) | GPIO_PIN(6) | GPIO_PIN(7) );   

}

/********************************************************************/

/*

* ISR for PORTC interrupts

*/

void portc_isr(void)

{

  if(PORTC_ISFR & GPIO_PIN(6))

  {

    printf("SW3 Pressed\n");

  }

  if(PORTC_ISFR & GPIO_PIN(7))

  {

    printf("SW2 Pressed\n");

  } 

  PORTC_ISFR=0xFFFFFFFF;  //Clear Port A ISR flags

}