56F8323 ADC Conversion triggered on interrupt

cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

56F8323 ADC Conversion triggered on interrupt

1,012 Views
mattkrolick
Contributor I

Hi all. I'm working with a 56F8323 DSP and I'm using Freescale CodeWarrior 5.9.0. I'm making full use of ADC and timer beans.

I'm having a problem where I can't seem to initiate an ADC conversion while in interrupt context. Application is basic, just running a timer which will interrupt every 10ms. In that interrupt routine, I want to start an ADC conversion and get the results before returning from the interrupt.

What seems to happen instead is that I get stuck in an infinite loop which checks for a flag that is never reset.

byte thermistorADC_Measure(bool WaitForResult)

{

  if (thermistorADC_ModeFlg != IDLE) { /* Is the device in running mode? */

    return ERR_BUSY;                   /* If yes then error */

  }

  thermistorADC_ModeFlg = MEASURE;     /* Set state of device to the measure mode */

  HWEnDi();                            /* Enable the device */

  if (WaitForResult) {                 /* Is WaitForResult TRUE? */

    while (thermistorADC_ModeFlg == MEASURE) {} /* If yes then wait for end of measurement */

  }

  return ERR_OK;                       /* OK */

}


Execution is stuck in that while loop. What I'd like to know is: why do ADC measurements fail to complete in interrupt context and is there a way around this other than setting a flag in the interrupt to be processed some time later?

Thanks

Labels (1)
Tags (3)
0 Kudos
Reply
1 Reply

622 Views
xiangjun_rong
NXP TechSupport
NXP TechSupport

Firstly, in the ADC bean, you should enable the ADC interrupt by selecting "Enable" in "Interrupt service/event" box, secondly, pls use the following code in the Events.c.

using the following code, I can enter the void AD1_OnEnd(void) function if I set a break point at asm(nop); line base on CW for DSP56800/E ver8.3.

#pragma interrupt called /* Comment this line if the appropriate 'Interrupt preserve registers' property */
                         /* is set to 'yes' (#pragma interrupt saveall is generated before the ISR)      */
void AD1_OnEnd(void)
{
  /* Write your code here ... */
  AD1_GetValue16(sample);
asm(nop);
}

/*
** ===================================================================
**     Event       :  TI1_OnInterrupt (module Events)
**
**     Component   :  TI1 [TimerInt]
**     Description :
**         When a timer interrupt occurs this event is called (only
**         when the component is enabled - <Enable> and the events are
**         enabled - <EnableEvent>). This event is enabled only if a
**         <interrupt service/event> is enabled.
**     Parameters  : None
**     Returns     : Nothing
** ===================================================================
*/
#pragma interrupt called /* Comment this line if the appropriate 'Interrupt preserve registers' property */
                         /* is set to 'yes' (#pragma interrupt saveall is generated before the ISR)      */
void TI1_OnInterrupt(void)
{
  /* Write your code here ... */
  AD1_Measure(FALSE);
  asm(nop);

}


0 Kudos
Reply