This discussion has been locked.

You can no longer post new replies to this discussion. If you have a question you can start a new discussion

LEDs and Push button interface problems

Karl over 10 years ago

Hi all, I have a Little problem getting my LPC2119 to work as I want it to.

Im running a ET-ARM et-arm stamp lpc2119 with GNU arm compiler in µVision3

Im trying to interface a push button with 2LEDs. Using one LED works but not 2. The compiler does not complain or give me an error.

Here is the code that works, a push button to p0.7 and a LED to p1.18


include <LPC21xx.H>                                 // LPC2119 MPU Register

int main(void)
 {
 PINSEL2 &= ~0x0000000C; // Makesure GPIO1.16-1.31 = GPIO Function,
 PINSEL0 &= ~0x0000C000;  //GPIO P0.7,
 IODIR1 |=(1<<18);  // GPIO 1.18 as output
 IODIR0  &=~((1<<7)); // Set GPIO0.7 AS input

while(1) // Loop Continue
 {

if(!(IOPIN0 & (1<<7))) // When button is pressed

{
  IOSET1 |=(1<<18);
 }
  else
 {
  IOCLR1 =(1<<18);
 }

Here is the code that does not work, 2 LEDs on p1.16 and p1.18, and the push button on p0.7

Im trying to set that when the button is pressed LED1 on and LED2 off, when button not pressed then LED2 on and LED2 off but it only works as Before with one LED turning on and off, the second LED never turns off.!! :(. What is it that I'm missing


include <LPC21xx.H>   // LPC2119 MPU Register

int main(void)
 {
 PINSEL2 &= ~0x0000000C; // Makesure GPIO1.16-1.31 = GPIO Function,
 PINSEL0 &= ~0x0000C000;  //GPIO P0.7,
 IODIR1 |=((1<<16)|(1<<18));  // GPIO p1.18 and p1.16 as output
 IODIR0  &=~((1<<7)); // Set GPIO0.7 AS input

while(1) // Loop Continue
 {

if(!(IOPIN0 & (1<<7))) // When button is pressed

{
  IOSET1 |=(1<<18);
  IOCLR1 =(1<<16);
 }
  else
 {
  IOCLR1 =(1<<16);
  IOCLR1 =(1<<18);
 }

}

}

Parents

0 Karl over 10 years ago in reply to ImPer Westermark


include <LPC21xx.H>   // LPC2119 MPU Register

int main(void)
 {
 PINSEL2 &= ~0x0000000C; // Makesure GPIO1.16-1.31 = GPIO Function,
 PINSEL0 &= ~0x0000C000;  //GPIO P0.7,
 IODIR1 |=((1<<16)|(1<<18));  // GPIO p1.18 and p1.16 as output
 IODIR0  &=~((1<<7)); // Set GPIO0.7 AS input

while(1) // Loop Continue
 {

if(!(IOPIN0 & (1<<7))) // When button is pressed

{
  IOSET1 |=(1<<18);
  IOCLR1 |=(1<<16);
 }
  else
 {
  IOSET1 |=(1<<16);
  IOCLR1 |=(1<<18);
 }

}

}

But this does not work either.

Reply

0 Karl over 10 years ago in reply to ImPer Westermark


include <LPC21xx.H>   // LPC2119 MPU Register

int main(void)
 {
 PINSEL2 &= ~0x0000000C; // Makesure GPIO1.16-1.31 = GPIO Function,
 PINSEL0 &= ~0x0000C000;  //GPIO P0.7,
 IODIR1 |=((1<<16)|(1<<18));  // GPIO p1.18 and p1.16 as output
 IODIR0  &=~((1<<7)); // Set GPIO0.7 AS input

while(1) // Loop Continue
 {

if(!(IOPIN0 & (1<<7))) // When button is pressed

{
  IOSET1 |=(1<<18);
  IOCLR1 |=(1<<16);
 }
  else
 {
  IOSET1 |=(1<<16);
  IOCLR1 |=(1<<18);
 }

}

}

But this does not work either.

Children

0 Karl over 10 years ago in reply to Karl

Hi, thanks for the reply;
Sorry, I wrote the second code based on the first one and Im at work and dont have my code in front of me. but you are correct. My code for 2 LEDs is

include <LPC21xx.H>   // LPC2119 MPU Register

int main(void)
 {
 PINSEL2 &= ~0x0000000C; // Makesure GPIO1.16-1.31 = GPIO Function,
 PINSEL0 &= ~0x0000C000;  //GPIO P0.7,
 IODIR1 |=((1<<16)|(1<<18));  // GPIO p1.18 and p1.16 as output
 IODIR0  &=~((1<<7)); // Set GPIO0.7 AS input

while(1) // Loop Continue
 {

if(!(IOPIN0 & (1<<7))) // When button is pressed

{
  IOSET1 |=(1<<18);
  IOCLR1 |=(1<<16);
 }
  else
 {
  IOSET1 |=(1<<16);
  IOCLR1 |=(1<<18);
 }

}

}

but this does not work either