data on pins changes when interrupt is used

lpcware — Thu, 16 Jun 2016 01:28:57 GMT

Content originally posted in LPCWare by aamir ali on Tue Dec 18 22:06:45 MST 2012
I have code, which changes port pins by masking. ALso a timer interrupt on regular basis of 250us come & chnage pins of that port.

Problem is when both occur at same time, data on port gets corrupted.How to avoid this.


void change()
{
  ........statemets
 .............
 LPC_GPIO->MASK[1] = ~(0x00f0);            
 LPC_GPIO->MPIN[1] = 0xa0;        
 LPC_GPIO->MASK[1] = 0x00; 
 ..................
 .................
}

void interrupt_any()
{
 LPC_GPIO->MASK[1] = ~(0x000f);
 LPC_GPIO->MPIN[1] = 0x0a;        
 LPC_GPIO->MASK[1] = 0x00; 
}

Re: data on pins changes when interrupt is used

lpcware — Thu, 16 Jun 2016 01:28:58 GMT

Content originally posted in LPCWare by micrio on Wed Dec 19 05:53:05 MST 2012
Sounds like you need to disable interrupts around the critical code.
Your code is not atomic so it needs to be protected.

topic data on pins changes when interrupt is used in LPCXpresso IDE

data on pins changes when interrupt is used

Re: data on pins changes when interrupt is used