#include "WProgram.h"

void SPI_MasterInit(void);
void clearScreen(boolean mode);
void blinkStatus(void);
void resetCursor(void);

#define PIN_SYNC			8
#define PIN_VIDEO			9
#define PIN_LED				12
#define PIN_AUDIO			11

#define _SYNC				0x00
#define _BLACK				0x01
#define _GRAY				0x02
#define _WHITE				0x03

#define _LONG_SYNC			19
#define _SHORT_SYNC			2
#define _LONG_SYNC_DELAI	2
#define _SHORT_SYNC_DELAI	30

#define _NB_PIXELS			29
#define _NB_LIGNES			19

//#define	_NB_TV_LIGNES	525
#define	_NB_TV_LIGNES		262

#define _COMPENS_BOUCLE		7
#define _COMPENS_IF_SERIAL	17

#define _BAUD_RATE			19200

byte memVideo[_NB_PIXELS][_NB_LIGNES];
byte index, index2;

int ligne;
char c;
int cx=(_NB_PIXELS / 2), cy=(_NB_LIGNES / 2);
byte couleur = _BLACK;

void SPI_MasterInit(void)
{
	/* Set MOSI and SCK output, all others input */
	DDRD = (1<<DDB0)|(1<<DDB1);
	/* Enable SPI, Master, set clock rate fck/16 */
	SPCR = (1<<SPE)|(1<<MSTR)|(1<<SPR0);
}

void clearScreen(boolean mode)
{
	for (index2 = 0; index2 < _NB_LIGNES; index2++)
		for (index = 0; index < _NB_PIXELS; index++)
			if (!mode) {
				memVideo[index][index2] = _BLACK;
			} else {
				memVideo[index][index2] = (index + index2) % 3 + 1;
			}
	
	memVideo[0][0] = _WHITE;
	
	resetCursor();
}

void resetCursor(void)
{
	cx=(_NB_PIXELS / 2);
	cy=(_NB_LIGNES / 2);
}

void blinkStatus(void)
{
	int ii;
	
	pinMode(PIN_LED, OUTPUT);
	
	for(ii=0;ii<3;ii++)
	{
		digitalWrite(PIN_LED, HIGH);
		delay(75);
		digitalWrite(PIN_LED, LOW);
		delay(75);
		digitalWrite(PIN_LED, HIGH);
		if (ii < 2) delay(75);
	}
}

void setup()
{
	pinMode(PIN_SYNC, OUTPUT);
	pinMode(PIN_VIDEO, OUTPUT);
	pinMode(PIN_AUDIO, OUTPUT);
	
	digitalWrite(PIN_SYNC, HIGH);
	digitalWrite(PIN_VIDEO, HIGH);
	
	//SPI_MasterInit();
	Serial.begin(_BAUD_RATE);
	Serial.println("GO");
	
	clearScreen(true);
	blinkStatus();
}

void loop()
{
	// SYNC VERT A
	
	// ligne 1 LONG SYNC
	PORTB = _SYNC; delayMicroseconds(_LONG_SYNC);
	PORTB = _BLACK; delayMicroseconds(_LONG_SYNC_DELAI);

	PORTB = _SYNC; delayMicroseconds(_LONG_SYNC);
	PORTB = _BLACK; delayMicroseconds(_LONG_SYNC_DELAI);

	// ligne 2 LONG SYNC
	PORTB = _SYNC; delayMicroseconds(_LONG_SYNC);
	PORTB = _BLACK; delayMicroseconds(_LONG_SYNC_DELAI);

	PORTB = _SYNC; delayMicroseconds(_LONG_SYNC);
	PORTB = _BLACK; delayMicroseconds(_LONG_SYNC_DELAI);

	// ligne 3 MIXTE SYNC
	PORTB = _SYNC; delayMicroseconds(_LONG_SYNC);
	PORTB = _BLACK; delayMicroseconds(_LONG_SYNC_DELAI);

	PORTB = _SYNC; delayMicroseconds(_SHORT_SYNC);
	PORTB = _BLACK; delayMicroseconds(_SHORT_SYNC_DELAI);

	// ligne 4 SHORT SYNC
	PORTB = _SYNC; delayMicroseconds(_SHORT_SYNC);
	PORTB = _BLACK; delayMicroseconds(_SHORT_SYNC_DELAI);

	PORTB = _SYNC; delayMicroseconds(_SHORT_SYNC);
	PORTB = _BLACK; delayMicroseconds(_SHORT_SYNC_DELAI);

	// ligne 5 SHORT SYNC
	PORTB = _SYNC; delayMicroseconds(_SHORT_SYNC);
	PORTB = _BLACK; delayMicroseconds(_SHORT_SYNC_DELAI);

	PORTB = _SYNC; delayMicroseconds(_SHORT_SYNC);
	PORTB = _BLACK; delayMicroseconds(_SHORT_SYNC_DELAI-_COMPENS_BOUCLE);

	// IMAGE

	for (ligne = 0; ligne < _NB_TV_LIGNES; ligne++)
	{
		//** synchro

		// HSync
		PORTB = _SYNC;
		delayMicroseconds(4.7);

		// Black
		PORTB = _BLACK;
		delayMicroseconds(4.7);
		
		//** image ligne 51.5 uS
		
		for (index = 0; index < _NB_PIXELS; index++)
		{
			PORTB = memVideo[index][ligne>>4];
			PORTB = PORTB;
			PORTB = PORTB;
		}
		
		delayMicroseconds(1.4); // 4 uS
		
		PORTB = _BLACK;
		PORTB = _BLACK;
		PORTB = _BLACK;
		PORTB = _BLACK;
		PORTB = _BLACK;

		PORTB = _BLACK;
		PORTB = _BLACK;
		PORTB = _BLACK;
		PORTB = _BLACK;
	}

	// SYNC VERT B
	
	// ligne 310 LONG SYNC
	PORTB = _SYNC; delayMicroseconds(_SHORT_SYNC);
	PORTB = _BLACK; delayMicroseconds(_SHORT_SYNC_DELAI);

	PORTB = _SYNC; delayMicroseconds(_SHORT_SYNC);
	PORTB = _BLACK; delayMicroseconds(_SHORT_SYNC_DELAI);

	// ligne 311 SHORT SYNC
	PORTB = _SYNC; delayMicroseconds(_SHORT_SYNC);
	PORTB = _BLACK; delayMicroseconds(_SHORT_SYNC_DELAI);

	PORTB = _SYNC; delayMicroseconds(_SHORT_SYNC);
	PORTB = _BLACK; delayMicroseconds(_SHORT_SYNC_DELAI);

	// ligne 312 SHORT SYNC
	PORTB = _SYNC; delayMicroseconds(_SHORT_SYNC);
	PORTB = _BLACK; delayMicroseconds(_SHORT_SYNC_DELAI);

	PORTB = _SYNC; delayMicroseconds(_SHORT_SYNC);
	PORTB = _BLACK; delayMicroseconds(_SHORT_SYNC_DELAI-_COMPENS_BOUCLE-_COMPENS_IF_SERIAL);
	
	if (Serial.available())
	{
		c = Serial.read();
		switch (c)
		{
			case '4' : if (cx>0) cx--; break;
			case '6' : if (cx<29) cx++; break;
			case '8' : if (cy>0) cy--; break;
			case '2' : if (cy<18) cy++; break;
			case '5' : memVideo[cx][cy] = couleur; break;
			case 'n' : couleur = _BLACK; break;
			case 'g' : couleur = _GRAY; break;
			case 'b' : couleur = _WHITE; break;
			case 'c' : clearScreen(false); break;
			case 'f' : clearScreen(true); break;
		}
	}
}