CodeWarrior for MCUのトピックRe: interrupt vector for mc68hc908qt4

interrupt vector for mc68hc908qt4

mevil — Thu, 22 Mar 2007 10:55:00 GMT

how mc68hc908qt4 handles the interrupt.

Im facing problem when using the adc interrupt of this particular chip.

i have written the code like this

interrupt 16 void adc_int (void)

{

/* reading the value of the adr register

}

i have done the init adc setting as

void initialise_adc(void) {

    ADSCR_AIEN = 1;
    ADSCR_ADCO = 0;
    ADICLK = 0X00;
   ADSCR_CH4 = 0;
   ADSCR_CH3 = 0;
  ADSCR_CH2 = 0;
   ADSCR_CH1 = 0;
   ADSCR_CH0 = 0;
    }

in main ()

{

initialise_adc();

}

bur during the debug it is giving the error as

Error - Attempt to set A/D channel to a reserved value

please help me on this topic

Re: interrupt vector for mc68hc908qt4

trytohelp — Tue, 27 Mar 2007 21:09:23 GMT

Hi,

Your request is asking some investigation.

It will be better to log this issue in the CRM system.
- Go to following URL: http://www.freescale.com/TechSupport
- Click on Submit a Service Request. You will come to a login page.
- You can submit your request through the web from there.

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Or you can save them in a txt file.

+ your example code reproducing the problem (the project folder in a zip file).

Pascal

Re: interrupt vector for mc68hc908qt4

bigmac — Wed, 28 Mar 2007 03:42:44 GMT

Hello,

It would seem that your problem occurs because you attempt to write the channel select bits individually - all five bits should be written in a single operation. Each time these bits are written this will cause a conversion to commence for the selected channel.

void initialise_adc(void)

{
ADICLK = 0x00;

   ADSCR_AIEN = 1;
   ADSCR_ADCO = 0;
   ADSCR_ADCH = 0; /* Start conversion on Ch 0 */
}

Regards,

Mac