#include <16F688.h>
#include <ctype.h>
#include <stdlib.h>

//#fuses HS,NOWDT,NOPROTECT,NOBROWNOUT,NOMCLR,PUT
//#use delay(clock=20000000)
#fuses INTRC_IO,NOWDT,NOPROTECT,NOBROWNOUT,MCLR,PUT
#use delay(clock=8000000)
#use rs232(stream=console,baud=9600,parity=N,bits=8,XMIT=PIN_C4,RCV=PIN_C5,ERRORS)

/////////////////////// pinout: PIC16F688
#define MT_CARD	PIN_A0
#define MT_DATA	PIN_A1
#define MT_CLK	PIN_A2	// must be RA2, the external interrupt pin
#define BUTTON1 PIN_A3
#define LED2		PIN_A4

#define LED1		PIN_C3
#define LCD_ECLK	PIN_C0
#define LCD_DCLK	PIN_C1
#define LCD_DATA	PIN_C2

// 1 - vdd+		vss-	 	- 14
// 2 - reader?	ra5	ra0 MTcard	- 13
// 3 - led2	ra4	ra1 MTdata	- 12
// 4 - reset	ra3	ra2 MTclk	- 11
// 5 - debugrx	rc5	rc0 lcdEclk	- 10
// 6 - debugtx	rc4	rc1 lcdDclk	- 9
// 7 - led1	rc3 	rc2 lcdData	- 8

/////////////////////// prototypes
int init();
/////////////////////// prototypes: magtek stuff
int magtek_read();
/////////////////////// prototypes: rs232 stuff
// signed int get_int();
// void get_string(char* s, int max);
// char fgetc_timed();
/////////////////////// prototypes: lcd stuff
int lcd_init();
int lcd_nibble(int8 rsbit, char out);
int lcd_putc(char c);
int lcd_clear();
int lcd_clearregister();
int lcd_gotoxy(int x, int y);

/////////////////////// main
void main() {
	// fprintf(console,"start...\r\n"); 
	output_high(LED2);
	init();
	// fprintf(console,"prelcdinit...\r\n"); delay_ms(3000);
	lcd_init();
	// fprintf(console,"preclear...\r\n"); delay_ms(3000);
//	lcd_clear();
	// fprintf(console,"waiting for mag swipe...\r\n");
//	lcd_clear();
//	printf(lcd_putc,"init...");
//	delay_ms(2000);
	lcd_clear();
	delay_ms(500); output_low(LED2);
	printf(lcd_putc,"Ready for swipe");
	delay_ms(500);
	// fprintf(console,"ready...\r\n"); 
	magtek_read();
	output_low(LED2); // card removed
	// lcd_gotoxy(1,2);
	// fprintf(console,"done.\r\n");
	while(1) {
		output_high(LED1); delay_ms(100);
		output_low(LED1); delay_ms(1900);
	}
}

/////////////////////// general functions

int init() {
	output_low(LED1);
	output_low(LCD_ECLK); output_low(LCD_DCLK); output_low(LCD_DATA);
	switch ( restart_cause() ) {
		case NORMAL_POWER_UP: { output_high(LED1); break; }
		default: { output_high(LED1); break; }
	}
	return 0;
}

/////////////////////// rs232 Functions
////// put these back for debugging
// signed int get_int();
// void get_string(char* s, int max);
// char fgetc_timed();

/////////////////////// LCD Functions

int lcd_init() {
	int8 i;
	lcd_clearregister(); //extra

	for(i=0;i<3;++i) { lcd_nibble(0,0x30); } // init
	lcd_nibble(0,0x20); // 4bit mode
	lcd_nibble(0,0x10); lcd_nibble(0,0x80); // 2rows,5x7
	lcd_nibble(0,0x10); lcd_nibble(0,0x00); // display off
	lcd_nibble(0,0x00); lcd_nibble(0,0x10); // display clear
	lcd_nibble(0,0x10); lcd_nibble(0,0x80); // setup cursor move
	lcd_nibble(0,0x00); lcd_nibble(0,0xF0); // enable display/cursor

	return 0;
}
int lcd_clearregister() {
	int8 i;
	output_low(LCD_DATA); output_low(LCD_DCLK); output_low(LCD_ECLK);
	for(i=0;i<5;++i) {	// spin the clock
		output_high(LCD_DCLK); 
		output_low(LCD_DCLK);
	}
	return 0;
}

int lcd_nibble(int8 rsbit, char out) {
	int8 i;

	lcd_clearregister();

	// fprintf(console,"LCD: %x\r\n",out);

	output_bit(LCD_DATA,rsbit);
	output_high(LCD_DCLK);	delay_cycles(1);
	output_low(LCD_DCLK);
	for (i=0;i<4;i++) {
		output_low(LCD_DCLK);
		output_bit(LCD_DATA, shift_left(&out,1,0));
		output_high(LCD_DCLK);	delay_cycles(1);
		output_low(LCD_DCLK);
	}
	output_low(LCD_DCLK);
	output_high(LCD_ECLK);	delay_cycles(1);
	output_low(LCD_ECLK);	delay_ms(5);
	return 0;
}

int lcd_putc(char c) {
	lcd_nibble(1, c); delay_cycles(1);
	shift_left(&c,1,0); shift_left(&c,1,0);
	shift_left(&c,1,0); shift_left(&c,1,0);
	lcd_nibble(1, c); delay_cycles(1);
	return 0;
}

int lcd_clear() {
	lcd_nibble(0,0x00); lcd_nibble(0,0x10); // display clear
	return 0;
}


int lcd_gotoxy(int x, int y) {
	int i;
	byte addr;
	if (y>1) { addr=0x40; } else { addr=0; }
	addr+=x-1; addr=0x80 | addr;
	lcd_nibble(0, addr); 
	for(i=0;i<4;++i) { shift_left(&addr,1,0); }
	lcd_nibble(0, addr); 
	return 0;
}

/////////////////////// Magtek Functions
int magtek_read() {
	int i,j,k;
	int bit;
	int done;
	int bitnum;
	int started;
	int thebyte;
	char value;
	int bytenum;
	int result[48];

	started=0;
	bytenum=0;
	done=0;
	while(!done) {
		if (!input(MT_CARD)) {
			output_high(LED1); // card present
			output_high(LED2); // card present
			// fprintf(console,"Card inserted!\r\n");
			while (!input(MT_CARD)) {
				// wait until the clock is low
				while (input(MT_CLK) && !input(MT_CARD)) { }
				// wait for the clock to go high
				while (!input(MT_CLK) && !input(MT_CARD)) { }
				// just went high
				bit = !input(MT_DATA);
				if (!started && bit) {
					started=1; bitnum=1;
				}
				if (started) {
					// fprintf(console,"%d", bit);
					shift_left(&thebyte,1,bit);
					if (bitnum > 4) {
						shift_left(&thebyte,1,0); shift_left(&thebyte,1,0); shift_left(&thebyte,1,0);
						result[bytenum] =thebyte;
						bytenum++;
						// fprintf(console," (%x)", thebyte);
						bitnum=1;
					} else { bitnum++; }
				}
			}

			// TODO: once the card goes away, perform parity and
			// LRC checks, and output the data XXX

			//delay_ms(200);
			// fprintf(console,"Card removed!\r\n");
			output_low(LED1); // card removed
			started=0;
			done=1;
			j=0; k=0;
			lcd_clear();
			for (i=0;i<=bytenum;i++)  {
				switch (result[i]) {
					case 0xd0: { value=0; break; } //start sentinal
					case 0x08: { value='0'; break; }
					case 0x80: { value='1'; break; }
					case 0x40: { value='2'; break; }
					case 0xc8: { value='3'; break; }
					case 0x20: { value='4'; break; }
					case 0xa8: { value='5'; break; }
					case 0x68: { value='6'; break; }
					case 0xe0: { value='7'; break; }
					case 0x10: { value='8'; break; }
					case 0x98: { value='9'; break; }
					case 0xb0: { value='|'; break; } // field separator
					case 0xf8: { value=0; break; } //end sentinal
					case 0x00: { value=0; break; } //
					default: { value=result[i]; }
				}
				if (value!=0) {
					j++; k++;
					if (k==17) { lcd_gotoxy(1,2); } 
					if (k>33) { return 1; }
				       	// if (j > 4) { j=0; printf(lcd_putc,"_"); }
					// fprintf(console,"%c", value);
					printf(lcd_putc,"%c", value);
				} else {
					// fprintf(console,"ZZ", value);
				}
			}
			bytenum=0;
		 // fprintf(console,"\r\n");
		}
	}
	return 0;
}