Unable to detect Button press on MSP-EXP430FR5969 Launchpad

Raghu Devisetti

Other Parts Discussed in Thread: MSP-EXP430FR5969

DEar All,

Today I tried to test the button interface of the MSP-EXP430FR5969 Launchpad, button could not for some reason. Any of you please let me know how can I successfully detect the button press.

I have used the Blink program and modified the same to detect the button press and release. But the pin status to which the button is connected always shows 0 whether it is pressed or released.

My source code to test the button interface is as follows....Please let me know if the code is correct or anything missing or wrong.

void main (void)
{
BSP_Init();

P1DIR |= 0x01; // Set P1.0 to output direction
P4DIR |= 0x40; // Set P4.6 to output direction

P1DIR &= 0xFD; // Set P1.1 to input direction
P4DIR &= 0xDF; // Set P4.5 to input direction

while(1)
{
if(P4IN & 0x20)
{
P4OUT &= 0xDF;
}
else
{
P4OUT |= 0x40;

}

if(P1IN & 0x02)
{
P1OUT &= 0xFE;
}
else
{
P1OUT |= 0x01;

}
}

}

Thanks,

Raghu Devisetti

over 11 years ago

0 old_cow_yellow over 11 years ago

Guru 58965 points

You probably need to pull up the input pins for the buttons.

0 Raghu Devisetti over 11 years ago in reply to old_cow_yellow

Intellectual 950 points

Thank you friend, let me try the same.

Thanks,

Raghu Devisetti

0 old_cow_yellow over 11 years ago in reply to Raghu Devisetti

Guru 58965 points

#include <msp430.h>
void main (void)
{
//BSP_Init();
// *** I do not know if BSP_Inits() does the following *** 
  WDTCTL = WDTPW | WDTHOLD;
  PM5CTL0 &= ~LOCKLPM5;  
  P1OUT = 0x02;
  P4OUT = 0x20;
  P1REN = 0x02;
  P4REN = 0x20;
// **** But the above is all you need ***

  P1DIR |= 0x01; // Set P1.0 to output direction
  P4DIR |= 0x40; // Set P4.6 to output direction

  P1DIR &= 0xFD; // Set P1.1 to input direction
  P4DIR &= 0xDF; // Set P4.5 to input direction

  while(1)
  {
    if(P4IN & 0x20)
    {
      P4OUT &= 0xBF;
    }
    else
    {
      P4OUT |= 0x40;
    }  

    if(P1IN & 0x02)
    {
      P1OUT &= 0xFE; 
    } 
    else
    {
      P1OUT |= 0x01;
    }
  }

}

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Unable to detect Button press on MSP-EXP430FR5969 Launchpad