f_12_12_adc_ser2.c

* Use 10 MHz crystal frequency. * Use Timer0 for ten millisecond looptime. * Blink "Alive" LED e

// For MCC18, this file uses the -Oi flag, which
// turns on integer promotions so that (ADRESH << 8) works.


#include        "config.h"
#include        "delay.h"
#include        "serial.c"
#include        "serio.c"
#include	"jwb.h"

/*
 * program to read ADC with ADC IRQs
 */

void	init(void);
void	char2hex(unsigned char c, unsigned char *s);
void	int2hex(int c, unsigned char *s);
void	Adc2Hex(int c, unsigned char *s);
void	SelectAdcChannel(unsigned char c);
unsigned char		ReadPot(void);
int		ReadTemp(void);
int		ReadAdcChannel(unsigned char c);

void	StartAdcCycle(unsigned char c);

extern void serial_init (char brg, char hi_speed);

const unsigned char MESSAGE1[]	=	"turn pot";
unsigned char str1[9];
unsigned char str2[9];


#define		ADC_AN0		0
#define		ADC_AN1		1
#define		ADC_IDLE	255

volatile unsigned char		AdcState;
volatile int				adc0;
volatile int				adc1;

#if defined(HI_TECH_C)
void interrupt pic_isr(void)
#endif
#if defined(__18CXX)
#pragma interrupt pic_isr
void pic_isr(void)
#endif
{
	unsigned char temp;

	if (ADIF) {
		ADIF = 0;
		switch (AdcState) {
			case ADC_AN0:
				if ( ADFM )
					adc0 = ((ADRESH << 8) | ADRESL);
				else
					adc0 = ((ADRESH << 2) | (ADRESL>>6));
				temp = ADCON0 & 0xC1;	// clear bits except ADCS1:ASCS0 and ADON
				//ADCON0 = temp | 0x20;	// select the RA5/AN4 (pot)
				ADCON0 = temp | 0x08;	// select the AN1
				AdcState = ADC_IDLE;
				break;
			case ADC_AN1:
				if ( ADFM )
					adc1 = ((ADRESH << 8) | ADRESL);
				else
					adc1 = ((ADRESH << 2) | (ADRESL>>6));
				temp = ADCON0 & 0xC1;	// clear bits except ADCS1:ASCS0 and ADON
				ADCON0 = temp;			// select the RA0/AN0
				AdcState = ADC_IDLE;
				break;
			case ADC_IDLE:
				// shouldn't ever get here!
				break;
	    }
	}
}

void StartAdcCycle(unsigned char c) {
	AdcState = c;
	GODONE = 1;
}

void main(void)
{
	unsigned char		c;

	double				va0, va1;

	init();

	AdcState = ADC_IDLE;
	IPEN = 0; ADIE = 1; PEIE = 1; GIE = 1;

	printf("Hit any key to read ADCs...");  pcrlf();

	while(1)
	{
		c = getch();
		StartAdcCycle(ADC_AN0);
		printf("AN0=");
		while (AdcState != ADC_IDLE);
		va0 = 5.0 * adc0/1024;			// convert LM34 value to temperature
		StartAdcCycle(ADC_AN1);
		printf("%4d (%1.3fV)     AN1=", adc0, va0 );
		while (AdcState != ADC_IDLE);
		va1 = 5.0 * adc1/1024;				// convert pot value to voltage (Vdd=5V)
		printf("%4d (%1.3fV)", adc1, va1);
		pcrlf();
	}
}

// initialize the PIC and peripherals
void init(void)
{
	PORTA = 0x00;
	ADCON0 = BIT7|BIT6|BIT0;								// internal ADC oscillator + ADON
	ADCON1 = BIT6|0x4;										// L.just, AN0+AN1+AN3, no ext REFs

	SET_AS_INPUT(TRISA, BIT0 | BIT1);						// inputs for Two ADC channels

	PORTB = 0x00;
	SET_AS_OUTPUT(TRISB, BIT0 | BIT1 | BIT2 | BIT3 | BIT4 | BIT5 );		// set RB0-RB5 to output
	// recall that RB6 and RB7 are reserved for the HW programmer/debugger

	PORTC = 0x00;
	SET_AS_OUTPUT(TRISC, BIT0 | BIT1 | BIT2 | BIT3 | BIT4 | BIT5);		// RC0,RC3,RC5 drive DAC
	// RC6 and RC7 are used in serial UART, so leave them alone

	// initialize the serial port
	serial_init(95, 1);		// setup 19200 baud serial IO

}

int		ReadAdcChannel(unsigned char c)
{
	unsigned char	temp;
	
	temp = ADCON0 & (BIT7|BIT6|BIT0);	// clear bits except ADCS1:ASCS0 and ADON
	ADCON0 = temp | ((c & 0x7)<<3);		// select the desired ADC channel and write to ADCON0
	DelayUs(20);						// wait 20us for ADC to get ready
	GODONE = 1;							// start ADC conversion
	while(GODONE);						// then wait for ADC to finish
	if ( ADFM )
		return ((ADRESH << 8) | ADRESL);
	else
		return ((ADRESH << 2) | (ADRESL>>6) );
}


void	SelectAdcChannel(unsigned char c)
{
	unsigned char	temp;
	
	temp = ADCON0 & (BIT7|BIT6|BIT0);	// clear bits except ADCS1:ASCS0 and ADON
	ADCON0 = temp | ((c & 0x7)<<3);		// select the desired ADC channel and write to ADCON0
}

//for MCC18, place the interrupt vector goto
#if defined(__18CXX)
#if defined(HIGH_INTERRUPT)
#pragma code HighVector=HIGH_INTERRUPT
#else
#pragma code HighVector=0x0008  
#endif
void HighVector (void)
{
    _asm goto pic_isr _endasm
}
#pragma code
#endif