ez430-RF2500 Help Thread

Hi Freelancer,

The easiest way to accomplish this is to use a GPIO interrupt driven event or function-based polling. See this file msp430x22x4_p1_02.c from our code examples for this part: http://www.ti.com/lit/zip/slac123 With this code you can toggle the LED in the interrupt service routine. If you still prefer polling P1_01 illustrates the way you poll the appropriate GPIO flag.

Please let me know if you have any further issues.

Thanks for the help Brandon.

I took function and implemented it in the following way (the button is on P1.2 instead of P1.3 right?):

int hitkey = 0;

void main(void)
{
  WDTCTL = WDTPW + WDTHOLD;
  P1IE |= 0x04;                             // P1.2 interrupt enabled
  P1IES |= 0x04;                            // P1.2 Hi/lo edge
  P1IFG &= ~0x04;                           // P1.2 IFG cleared

  while(1)
  {   
    if (hitkey != 0)
    {
      // Do Stuff
    }
  __bis_SR_register(LPM4_bits + GIE);       // Enter LPM4 w/interrupt
  }
}

// Port 1 interrupt service routine
#pragma vector=PORT1_VECTOR
__interrupt void Port_1(void)
{
  hitkey ^= 0x01;
  P1IFG &= ~0x04;                           // P1.2 IFG cleared
}

I set a breakpoint within the interrupt, but it never hits there. Is there something I'm doing wrong?

Hi Freelancer,

here is a bit of code that works with the push button on the RF2500 Target board.

You will have to press in the middle of the push button, as the push is not always recognized.

Also, pay attention to the debouncing for-loop which is missing in your code - you may try adding that one first.

Also the interrupt function name has the _ISR extension, not sure if this mandatory or not, though.

/*------------------------------------------------------------------------------
* Push BUTTON on RF2500 Target Board ISR
------------------------------------------------------------------------------*/
#pragma vector=PORT1_VECTOR
__interrupt void Port1_Button_ISR (void)
{ 
  for(unsigned int i=0; i<=2000;i++);
  P1IFG &= ~BIT2;
  button_pushed = 1;   
  __bic_SR_register_on_exit(LPM3_bits);        // Clear LPM3 bit from 0(SR)
}

In your main() you should have this:

*****

    if (button_pushed) { //Flag is set by Push Button ISR
        //BSP_TOGGLE_LED2(); if you like
      //do your stuff here
       button_pushed = 0;

}

The example is based on the Wireless sensor monitor (the default SW with the kit).

Let me know if it works for you!

Br,

Odessos

Hi Odessos,

this is my code about how to use pushbutton to triggle LED. I use RF2500, I don't know why.

I have the same problem.

why I cannot let pushbutton work. here is my code.

int main( void )
{
  // Stop watchdog timer to prevent time out reset
  WDTCTL = WDTPW + WDTHOLD;
 
  P1DIR |= 0x01; // P1.0 output 
 
  P1IE |= 0x04;                             // P1.2 interrupt enabled
  P1IES |= 0x04;                            // P1.2 Hi/lo edge
  P1IFG &= ~0x04;   
  __bis_SR_register(LPM4_bits + GIE); 

}

#pragma vector=PORT1_VECTOR
__interrupt void Port_1(void)
{
  P1OUT ^= 0x01;                            // P1.0 = toggle
  P1IFG &= ~0x04;                           // P1.2 IFG cleared
}

Thank you for your help

Hi Odessos,

I gave that a shot, but unfortunately that didn't work either.  I can't imagine what I did wrong before in my code, and what I'm doing wrong right now.  Do you think that you could paste your complete code for that one file that you are using?  Maybe there is something in the headers that I haevn't set right.  Here is my complete code with your suggestions used.  If you could take a look at it that would be great.

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

Title: testthing.c
Author: Freelancer
Date Created: Aug 28, 2008

Description:
A test program written to play around with the EZ430 Development Kit.

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

#include "msp430x22x4.h"

void getBtn(void);
void LEDOn(void);
void LEDOff(void);
void LEDRed(void);
void LEDGreen(void);
void swDelay(unsigned int cnt);
//__interrupt void Port_1();

int hitkey = 0;

void main(void)
{
  WDTCTL = WDTPW + WDTHOLD;
  //GIE;
  P1IE |= 0x04;                             // P1.2 interrupt enabled
  P1IES |= 0x04;                            // P1.2 Hi/lo edge
  P1IFG &= ~0x04;                           // P1.2 IFG cleared

  while(1)
  {
    //hitkey = 0;
    //LEDOff();   
    if (hitkey != 0)
    {
      LEDRed(); swDelay(1); LEDOff(); swDelay(1);
      LEDGreen(); swDelay(1); LEDOff(); swDelay(1);
      LEDOn(); swDelay(1); LEDOff(); swDelay(1);
    }
  //__bis_SR_register(LPM4_bits + GIE);       // Enter LPM4 w/interrupt
  }
}



// |***************************************************************************|
// |                                                                           |
// |               F U N C T I O N   D E F I N I T I O N S                     |
// |                                                                           |
// |***************************************************************************|


void getBtn(void)
{
  P1DIR &= ~(BIT2);       // Set P1.2 to input direction
  P1SEL &= ~(BIT2);          // P1.2 set to I/O option
  hitkey = P1IN & BIT2;   // AND with BIT2 to get just the value of P1.2
}

void LEDOn(void)
{
  P1DIR |= (BIT1|BIT0);   // Set P1.1-1.0 to output direction
  P1SEL &= ~(BIT1|BIT0);  // P1.1-1.0 I/O option
  P1OUT |= (BIT1|BIT0);   // P1.1-1.0 output = 1, LED ON
}

void LEDOff(void)
{
  P1DIR |= (BIT1|BIT0);   // Set P1.1-1.0 to output direction
  P1SEL &= ~(BIT1|BIT0);  // P1.1-1.0 I/O option 
  P1OUT &= ~(BIT1|BIT0);  // LED Off
}

void LEDRed(void)
{
  P1DIR |= (BIT1|BIT0);   // Set P1.1-1.0 to output direction
  P1SEL &= (BIT1|BIT0);   // P1.1-1.0 I/O option
  P1OUT &= ~(BIT1|BIT0);  // Clear LED ports
  P1OUT |= (BIT0);        // P1.0 On
}

void LEDGreen(void)
{
  P1DIR |= (BIT1|BIT0);   // Set P1.1-1.0 to output direction
  P1SEL &= (BIT1|BIT0);   // P1.1-1.0 I/O option 
  P1OUT &= ~(BIT1|BIT0);  // Clear LED ports
  P1OUT |= (BIT1);        // P1.1 On
}

void swDelay(unsigned int cnt)
{
  int i, i2 = 0;
  while (i2 <= cnt)
  {
    for(i = 0; i < 0xFFFF; i++){}
    i2++;
  }
}

/*
// Port 1 interrupt service routine
#pragma vector=PORT1_VECTOR
__interrupt void Port1_Button_ISR(void)
{
  //P1OUT ^= 0x01;                            // P1.0 = toggle
  hitkey ^= 0x01;
  P1IFG &= ~0x04;                           // P1.3 IFG cleared
}
*/

#pragma vector=PORT1_VECTOR
__interrupt void Port1_Button_ISR (void)
{
  for(unsigned int i=0; i<=2000;i++);
  P1IFG &= ~BIT2;
  hitkey = 1;  
  __bic_SR_register_on_exit(LPM3_bits);        // Clear LPM3 bit from 0(SR)
}

Freelancer said:

how I can write the interrupt for the button

The button on the eZ430-RF2500 is on P1.2 and takes advantage of the MSP430's internal pullups.  By default, the pull up is disabled and the button will not do anything unless this is configured.  This is why all the code above doesn't work.  The key line everyone is missing is "P1REN |= 0x04;".

I've attached a code example that uses the button to cycle through the LEDs which you can import into your project (rename to *.c.  The forum doesn't allow posting *.c files for some reason.)

or you can cut & paste the following:

//******************************************************************************
// Enable the button on the eZ430-RF2500 (P1.2) using the internal pull-up to
// cycles between the LEDs.
//
//               MSP430F22x4
//            -----------------
//        /|\|                 |
//         | |                 |
//         --|RST              |
//           |             P1.1|-->LED
//      --o--|P1.2         P1.0|-->LED
//     \|/
//
//  A. Valenzuela
//  Texas Instruments Inc.
//  May 2007
//******************************************************************************
#include "msp430x22x4.h"

void main(void)
{
  WDTCTL = WDTPW + WDTHOLD;                 // Stop watchdog timer
  BCSCTL3 |= LFXT1S_2;                      // LFXT1 = VLO
  IFG1 &= ~OFIFG;                           // Clear OSCFault flag
  __bis_SR_register(SCG1 + SCG0);           // Stop DCO
  BCSCTL2 |= SELM_3 + DIVM_3;               // MCLK = LFXT1/8

  P1DIR |= 0x03;                            // Set P1.0, P1.1 to output
  P1OUT &= ~0x3;                             //P1.0, P1.1 low
  P1IE |= 0x04;                             // P1.2 interrupt enabled
  P1IES |= 0x04;                            // P1.2 Hi/lo edge
  P1IFG &= ~0x04;                           // P1.2 IFG cleared
  P1REN |= 0x04;                            // P1.2 pullup
  P1OUT |= 0x04;                            // P1.2 pullup

  __bis_SR_register(LPM3_bits + GIE);       // Enter LPM4 w/interrupt
}

// Port 1 interrupt service routine
#pragma vector=PORT1_VECTOR
__interrupt void Port_1(void)
{
  while(!P1IN&0x04);                        // Wait for button debounce
                                            // remove while() if delay_cyles used
  P1OUT++;                                  // Cycle LEDs
  P1OUT &= 0x03;                            // LED Circular Buffer
  P1OUT |= 0x04;                            // P1.2 pullup
  P1IFG &= ~0x04;                           // P1.2 IFG cleared
  //__delay_cycles(500);                      // Button delay (IAR & CCE v3.1+)
}

I have posted similar question in another thread ( wrong thread): how do I get  temperature and humidity sensors built  like the demo ( zigbee demo msp 430 -cc 2480)in a production mode, what is the price?

best regards,

Debebe Asefa

I was having similar problems with the push button sample code and then I found this post. Thanks a lot to the guys asking for help and big thanks to adrian for posting the solution. This was awesome help!

It would be nice if the next rev of SLAC123 code examples for 22x2 and 22x4 would be fixed to use the correct pin for the push button and add the missing P1REN line.

Adrian,

         Confirmed that the code works. Could you explain how this line does the debouncing?

while(!P1IN&0x03);                        // Wait for button debounce

the pushbutton is on P1.2 and you are applying a '0' to that bit thereby ignoring it. What does this line really do?

Thanks

Perl Smith said:

while(!P1IN&0x03);                        // Wait for button debounce

looks like that line is actually a typo.  it should have been halting program execution until P1.2 is released.  i've edited my original post to be accurate.  thanks for catching that!

the __delay_cycles line that is commented out is more effective at keeping multiple ISR from rapidly going off as you push the button.  it left it commented out because not all compilers have this intrinsic available.

Adrian,

        I don't see an update in your code. Are you sure you updated it?

Perl Smith said:

  I don't see an update in your code. Are you sure you updated it?

yeah, i'm sure.

Hello,

                Could someone explain why these lines are necessary in the above program?

BCSCTL3 |= LFXT1S_2; // LFXT1 = VLO (12kHz)

IFG1 &= ~OFIFG; // Clear OSCFault flag

__bis_SR_register(SCG1 + SCG0); // Stop DCO

BCSCTL2 |= SELM_3 + DIVM_3; // MCLK = LFXT1/8 (1.5kHz)

Thanks