comp.c

ADI公司的ARM7的功能模块的源码

/*********************************************************************

 Author        : ADI - Apps            www.analog.com/MicroConverter

 Date          : Sept. 2005

 File          : Comp.c

 Hardware      : Applicable to ADuC702x rev H or I silicon
                 Currently targetting ADuC7026.

 Description   : The comparator is configured to compare ADC2 
 				 with DAC0 and generates an interrupt on falling
				 and rising edge. P4.2 blinks at different speed 
				 depending on the type of edge
		
*********************************************************************/
#include<ADuC7026.h>

void delay(int);
void My_IRQ_Function(void);		//	IRQ Function Prototype 


unsigned int i;			

int main (void)  {

	GP4DAT = 0x04000000;		// P4.2 configured as an output. LED is turned on	
	REFCON = 0x01;				// internal 2.5V reference. 2.5V on Vref pin
	CMPCON = 0x6E4;			   	// ADC2 > DAC0 => CMPOUT = 1
								// ADC2 < DAC0 => CMPOUT = 0
	IRQ = My_IRQ_Function;		// Specify Interrupt Service Rountine 
	IRQEN = 0x10000;			// Enable Comparator

	DAC0CON = 0x13;				// DAC configuration
								// range AVdd/AGND
								// DAC0 is updated with falling edge of core clock
	DAC0DAT = 0x08000000;		// midscale
 
	while (1)
	{
	}				
}


 void delay (int length)
{
	while (length >=0)
	{
    	length--;
	}
}

/********************************************************************/
/*                                                                  */
/*		Interrupt Service Routine									*/
/*                                                                  */
/********************************************************************/

void My_IRQ_Function()				
{	
	if (CMPCON & 0x1) {				// falling edge	on CMPOUT
		CMPCON = 0x6E5;				// clear comparator int bit	
		for (i=0; i<=20; i++){
			delay(100000);	
			GP4DAT ^= 0x00040000;	// Complement P4.2
		}
	}
	if (CMPCON & 0x2) {				// rising edge on CMPOUT
		CMPCON = 0x6E6;				// clear comparator int bit	
		for (i=0; i<=10; i++){
			delay(200000);	
			GP4DAT ^= 0x00040000;		// Complement P4.2
		}
	}
	return ;
}