adctimer.c

ADuC7020/26是ADI模拟公司开发的ARM7TDMI内核

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

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

 Date          : Sept. 2005

 File          : ADCtimer.c

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

 Description   : Performs an ADC conversion every 91 us using timer0  
 				 overflow alternatively on Channel 0 and 1
 				 sending the results through UART at 9600bps
		
*********************************************************************/

#include <ADuC7026.h>				// 	Include ADuC7026 Header File
		
void IRQ_Handler(void) __irq;		//	IRQ Funtion Prototype 

void senddata(short to_send);
void ADCpoweron(int);
char hex2ascii(char toconv);
void delay(int);

									
int main (void)  {

	ADCpoweron(20000);				// power on ADC										
	ADCCP  = 0x00;
	ADCCON = 0x6E2;					// start conversion on timer 0

	REFCON = 0x01;					// connect internal 2.5V reference to VREF pin

	GP1CON = 0x011;	 				// Setup tx & rx pins on P1.0 and P1.1
 
   // Setting up UART at 9600bps (CD=0)
	COMCON0 = 0x80;					// Setting DLAB
	COMDIV0 = 0x88;			
   	COMDIV1 = 0x00;
   	COMCON0 = 0x07;					// Clearing DLAB


	// for test purposes only
	GP0CON = 0x10100000; 			// enable ECLK output on P0.7, and ADCbusy on P0.5


	IRQEN = ADC_BIT;				//	Enable ADC IRQ ( 0x80 )
	
	// timer0 configuration
	T0LD = 35530;					// 23.4us
	T0CON = 0xC8;					// count down
									// periodic mode

	GP4DAT = 0x04000000;			//	Configure P4.2 as output

	while(1)
	{

	}
                   
	return 0 ;
}


/********************************************************************/
/*                                                                  */
/*		Interrupt Service Rountine									*/
/*                                                                  */
/********************************************************************/

void IRQ_Handler() __irq				
{		
	GP4DAT ^= 0x00040000;			// Complement P4.2
//	ADCCP ^= 1;						// change channel
	senddata (ADCDAT >> 16);	
	return ;
}

void senddata(short to_send)
{
	while(!(0x020==(COMSTA0 & 0x020))){}
		COMTX = 0x0A;						// output LF 
	while(!(0x020==(COMSTA0 & 0x020))){}
		COMTX = 0x0D;						// output CR 
	while(!(0x020==(COMSTA0 & 0x020))){}
		COMTX = hex2ascii ((to_send >> 8) & 0x0F);
	while(!(0x020==(COMSTA0 & 0x020))){}
		COMTX = hex2ascii ((to_send >> 4) & 0x0F);						
	while(!(0x020==(COMSTA0 & 0x020))){}
		COMTX = hex2ascii (to_send & 0x0F);							
}


char hex2ascii(char toconv)
{
	if (toconv<0x0A) toconv += 0x30;
	else toconv += 0x37;	
	return (toconv);
}

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

void ADCpoweron(int time)
{
	ADCCON = 0x20;	 					// power-on the ADC
	while (time >=0)	  				// wait for ADC to be fully powered on
    time--;
}