Axon constantly resetting when I enable interrupts

[airman00]

I was working on interfacing a SmartCard and using interrupts and clock pulses and stuff. Then my Axon started acting all wierd and resetting. After some sleuthing I found the problem to be interrupts.
When I disable interrupts the axon does not reset. However if I don't disable interrupts then it constantly resets. I've commented out uartInit and rprintfInit as well as all the timer stuff, but no matter what I do if I don't put cli() then it will reset.
Any ideas how to fix this problem?

EDIT: Battery is fully charged and I double checked fuse settings - everything checks out.

Take a look this stripped down code:

Code: [Select]

int main(void)
{
int i=0;//useless variable
int j=0;//useless variable


/****************INITIALIZATIONS*******************/
uartInit();  // initialize the UART (serial port)
    uartSetBaudRate(0, 4800); // set UARTE speed, for Bluetooth  before was 115200
    uartSetBaudRate(1, 115200); // set UARTD speed, for USB connection
   uartSetBaudRate(2, 9600);
    uartSetBaudRate(3, 115200); // set UARTJ speed, for Blackfin


rprintfInit(uart1SendByte);// initialize rprintf system and configure uart1 (USB) for rprintf


// initialize the timer system (comment out ones you don't want)
// disable all these !!!
timer0Init();
timer1Init();
// timer2Init();
// timer3Init();
// timer4Init();
//timer5Init();

configure_ports(); // configure which ports are analog, digital, etc.

a2dInit(); // initialize analog to digital converter (ADC)
a2dSetPrescaler(ADC_PRESCALE_DIV32); // configure ADC scaling
a2dSetReference(ADC_REFERENCE_AVCC); // configure ADC reference voltage

LED_on();

rprintf("\r\nSystem Warming Up");

//let system stabelize for X time
for(i=0;i<=16;i++)
{
delay_cycles(5000);
rprintf(".");
}

delay_cycles(6000);

//read each ADC once to get it working accurately
for(i=0;i<16;i++)
{
j=a2dConvert8bit(i);
}
LED_off();
/**************************************************/

rprintf("Initialization Complete \r\n");
cli();   // disable interrupts.  if this is commented out then the Axon resets
while(!button_pressed()); //wait until user pushes button


while(1) {
control();
delay_cycles(100);
}

return 0;
}


[paulstreats]

does it have any kind of watchdog timer that needs resetting regularly?

[airman00]

does it have any kind of watchdog timer that needs resetting regularly?

no, and anyways a watchdog timer would be a fuse, with no relationship to any interrupts. ( i think)

[Webbot]

I think something is causing an interrupt but no ISR has been set up so it jumps to location 0 and reboots.

If your cut down code still gives the issue then try commenting out the stuff that will create interrupts but isn't used - ie the timers, uarts etc

rprintf can also do this if rprintfInit hasn't been called before its first used. So you can always write a dummy routine the just throws away the output ie

void chuck(char c){
}

and then rprintfInit(&chuck) at the top of your program. That will let you get rid of all the uart stuff as well.

Keep stripping until the problem goes.

[airman00]

Yea its definitely not a hardware issue, as I tested it with another program and hte Axon was fine.

I redid the code using the latest Axon source code and it works now.

@Webbbot
I'll try stripping it down as well because I'm curious to know what caused the reset.