// File : m11_adc.c 

#include <gc80c510_so20i.h>

#define ADC_DIVIDE_OSC_2   1
#define ADC_DIVIDE_OSC_4   2
#define ADC_DIVIDE_OSC_8   3
#define ADC_DIVIDE_OSC_16  4
#define ADC_DIVIDE_OSC_32  5
#define ADC_DIVIDE_OSC_64  6
#define ADC_DIVIDE_OSC_128 7
#define MAX_ADC 12

unsigned char channel;
unsigned char adc_intr;
unsigned int adc_result;
unsigned char value;

void m11_pwm_clock(unsigned char divide)
{
	PWMCON &= 0x8F;			
	PWMCON += (divide << 4);
}

void m11_adc_clock_divide(unsigned char divide)
{
	ADCON |= 0x04;
	m11_pwm_clock(divide);			
}

void m11_adc_channel_select_all()
{
	ADCSELH = 0x00;			
	ADCSEL &= 0x0F;			
}

void adc_enable()
{
	value = ADCON;			
	value |= 0x80;
	ADCON = value;	
}

void adc_disable()
{
	value = ADCON;			
	value &= 0x7f;
	ADCON = value;	
}

void adc_request()
{
	value = ADCON;			
	value |= 0x40;
	ADCON = value;	
}

void adc_clear_interrupt_flag()
{
	value = ADCON;			
	value &= 0xef;
	ADCON =  value;	
}

void m11_adc_mux_selection(unsigned char channel)
{
	ADCSEL &= 0xF0;			
	ADCSEL += channel;
}

unsigned int adc_10bit_result()
{
	unsigned int temp,temp1;
	temp = ADCON & 0x03;
	temp1 = ADCR << 2;
	temp1 += temp;
	return temp1;	
}

void adc_interrupt_enable()
{
	EADC = 1;
}

void adc_run(unsigned char channel)
{
	m11_adc_mux_selection(channel);
	adc_request();	
	while (!adc_intr);
	adc_intr = 0;
	adc_result = adc_10bit_result();
}

void enable_all_interrupt()
{
	EA = 1;
}

void adc_port_pullup_off()
{
	// P0.1 ~ P0.7, P2.2 ~ P2.6
	
	P0SEL |= 0x7F;
	P2SEL |= 0x7C;
}

void adc_init()
{
	adc_intr = 0;
	adc_port_pullup_off();
	
	enable_all_interrupt();
	adc_interrupt_enable();	
	adc_enable();
	
	m11_adc_clock_divide(ADC_DIVIDE_OSC_2);

	m11_adc_channel_select_all();	

	for(channel=0;channel<MAX_ADC;channel++) //MAX_ADC
	{
		adc_run(channel);
	}
}

void adc_int(void) interrupt ADC_VECTOR
{
	adc_clear_interrupt_flag();
	adc_intr = 1;
}

void use_external_clock()
{
	while (!(STATUS & 0x10)); 	// XTUP Check (Crystal AMP)	
	EXIF = EXIF | XTRG_;		// System Clock is Crystal Osc. (default =0, Ring Osc.)
}
void main()
{
	use_external_clock();
	adc_init();
	while(1);
}