#include "msp430g2231.h"
#include "stdbool.h"

#define TXD BIT1 		// TXD on P1.1
#define RXD BIT2 		// RXD on P1.2
#define REC BIT3		// start recording
#define Bit_time 104 	// (1MHz/9600)=104
#define Bit_time_5 52 	// Time for half a bit.
#define SAMPLES 100		// MAX

unsigned int BitCnt; 	// Bit count, used when transmitting byte
unsigned int TXByte; 	// Value sent over UART when Transmit() is called
unsigned int RXByte; 	// Value recieved once hasRecieved is set

bool isReceiving = false; 		// Status for when the device is receiving
bool isRecording = false;
bool hasReceived = false; 		// Lets the program know when a byte is received

bool MSG[SAMPLES] = {0};
bool CARD[SAMPLES] = {0};
bool CARD2[SAMPLES] = {8};

void ClearMSG(void);
bool Verify(bool DATA[]);

void main(void)
{
	WDTCTL = WDTPW + WDTHOLD; // Stop WDT

	BCSCTL1 = CALBC1_1MHZ; 	// Set range
	DCOCTL = CALDCO_1MHZ; 	// SMCLK = DCO = 1MHz

	P1SEL |= TXD;
	P1DIR |= TXD;

	P1IES |= RXD;		// RXD Hi/lo edge interrupt
	P1IFG &= ~RXD; 		// Clear RXD (flag) before enabling interrupt
	P1IE |= RXD; 		// Enable RXD interrupt

	P1IFG &= ~REC; 		// Clear RXD (flag) before enabling interrupt
	P1IE |= REC; 		// Enable RXD interrupt

	__bis_SR_register(GIE); // interrupts enabled
	while(1)
	{
		if (hasReceived) // If the device has recieved a value
		{
			if (Verify(CARD) == true){
				P1OUT |= BIT0;
			}else{
				P1OUT &= ~BIT0;
			}

			hasReceived = false; 	// Clear the flag
		}

		if (~hasReceived) // Loop again if another value has been received
			__bis_SR_register(CPUOFF + GIE);
	}
}

// Port 1 interrupt service routine
#pragma vector=PORT1_VECTOR
__interrupt void Port_1(void) // start recording
{
	isReceiving = true;
	if ((P1IN & REC) == REC){
		isRecording = true;
	}

	P1IE &= ~RXD;		// Disable RXD interrupt
	P1IFG &= ~RXD; 		// Clear RXD IFG (interrupt flag)
	P1IE &= ~REC;		// Disable RXD interrupt
	P1IFG &= ~REC; 		// Clear RXD IFG (interrupt flag)

	TACTL = TASSEL_2 + MC_2; 	// SMCLK, continuous mode
	CCR0 = TAR; 				// Initialize compare register
	CCR0 += Bit_time_5; 		// Set time till first bit
	CCTL0 = OUTMOD1 + CCIE; 	// Dissable TX and enable interrupts

	ClearMSG();
	BitCnt = SAMPLES - 1; // Load Bit counter, 8 bits + ST
}

// Timer A0 interrupt service routine
#pragma vector=TIMERA0_VECTOR
__interrupt void Timer_A (void)
{
	if(isReceiving) // receiving
	{
		CCR0 += Bit_time; // Add Offset to CCR0

		if ( BitCnt == SAMPLES - 1) //last bit
		{
			TACTL = TASSEL_2;	// SMCLK, timer off (for power consumption)
			CCTL0 &= ~ CCIE ;	// Disable interrupt

			isReceiving = false;

			P1IFG &= ~RXD;		// clear RXD IFG (interrupt flag)
			P1IE |= RXD;		// enabled RXD interrupt

			if (isRecording){ 	//dump
				int i;
				for (i=0; i<SAMPLES; i++){
					CARD[i] = MSG[i];
					MSG[i] = 0;
				}
				isRecording = false;
			}

			hasReceived = true;

			__bic_SR_register_on_exit(CPUOFF); // Enable CPU so the main while loop continues
		}
		else {
			if ( (P1IN & RXD) == RXD) // If bit is set?
				MSG[BitCnt] = 1;
			BitCnt ++;
		}
	}
	else 	//done receiving, turn off
	{
		CCR0 += Bit_time; 	// Add Offset to CCR0
		if ( BitCnt == SAMPLES - 1) // If all bits TXed
		{
			TACTL = TASSEL_2; // SMCLK, timer off (for power consumption)
			CCTL0 &= ~ CCIE ; // Disable interrupt
		}
	}
}

void ClearMSG(){
	int i;
	for (i=0; i<SAMPLES; i++){
		MSG[i] = 0;
	}
}

bool Verify(bool *DATA){
	int i;
	for (i=0; i<SAMPLES; i++){
		if (MSG[i] != DATA[i])
			return false;
	}
	return true;
}