/*************************************************************
ECE 473 Lab Assignment #2

Students: Philip Lechowicz
		  Olamide Adabonyan
Due Date: 10/28/02
**************************************************************/ 

/*************************************************************
*Header Files
**************************************************************/

#include <hc11.h>
#include <stdio.h>
#include <stdlib.h>
#include <Vector.h>

/*************************************************************
*Global Variables
**************************************************************/

unsigned int statusA = 0;
unsigned int statusB = 0;
unsigned int count = 120;
unsigned int dummy = 0;

/*************************************************************
Function: TOC2_ISR
Purpose: This interrupt occurs 10ms after the switch B is pressed
		 to avoid reading signal while switch is bouncing.  The
		 interrupt inables IC1 and IC2 for the next time the 
		 switch is pressed.  Additionally, it reads PA1; if 
		 high, the switch is pressed and a global status variable 
		 is set to take appropriate action in main.
Inputs: None
Outputs: None
**************************************************************/

#pragma interrupt_handler	TOC2_ISR
void T0C2_ISR(void)
{
	printf("\nWaited for switch debounce");
	TMSK1 = 0x06; /*Enable IC2, IC1 Interrupt1, Disable others*/
	TFLG1 = 0x06; /*Clear IC1F and IC2F*/
	if ((PORTA & 0x02)==0x02) /*Check to see if signal is high*/
		statusB = 1;  /*If high, Set "statusB flag" to take action in main*/
	asm("rti");
}

/*************************************************************
Function: TOC1_ISR
Purpose: This interrupt occurs 10ms after the switch A is pressed
		 to avoid reading signal while switch is bouncing.  The
		 interrupt inables IC1 and IC2 for the next time the 
		 switch is pressed.  Additionally, it reads PA2; if 
		 high, the switch is pressed and a global status variable 
		 is set to take appropriate action in main.
Inputs: None
Outputs: None
**************************************************************/

#pragma interrupt_handler	TOC1_ISR
void TOC1_ISR(void)
{
	printf("\nWaited for switch debounce");
	TMSK1 = 0x06; /*Enable IC2, IC1 Interrupts, Disable others*/
	TFLG1 = 0x06;  /*Clear IC1F and IC2F flags*/
	if ((PORTA & 0x04)==0x04) /*Check to see if signal is high*/
		statusA = 1;  /*If high, Set "statusA flag" to take action in main*/
	asm(" rti");
}


/*************************************************************
Function: TIC2_ISR
Purpose: This Interrupt occurs when switch B (PA1)has a rising or 
		 falling edge.  The tasks of this interrupt are to disable 
		 the IC interrupts, and then enable the OC2 interrupt to 
		 occur 10ms later.  This is to avoid reading the switch 
		 while it is bouncing.
Inputs: None
Outputs: None
**************************************************************/

#pragma interrupt_handler	TIC2_ISR
void TIC2_ISR(void)
{  
	printf("\nSwitch on PA1 was pressed"); 	 	 
	TMSK1 = 0x40; /*Enable OC2 Interrupt, Disable others*/
	TOC2 = TCNT + 20000;
	TFLG1 = 0x40;  /* Clear OC2F */
	asm(" rti");
}


/*************************************************************
Function: TIC1_ISR
Purpose: This Interrupt occurs when switch A (PA2)has a rising or 
		 falling edge.  The tasks of this interrupt are to disable 
		 the IC interrupts, and then enable the OC2 interrupt to 
		 occur 10ms later.  This is to avoid reading the switch 
		 while it is bouncing.
Inputs: None
Outputs: None
**************************************************************/
#pragma interrupt_handler	TIC1_ISR
void TIC1_ISR(void)
{
	printf("\nSwitch on PA2 was pressed");
	TMSK1 = 0x80; /*Enable OC1 Interrupt, Disable others*/
	TOC1 = TCNT + 20000;
	TFLG1 = 0x80;  /* Clear OC1F */
	asm(" rti");
}


/*************************************************************
Function: RTI_ISR
Purpose: This Interrupt occurs at period of 4.096 ms.  The
		 purpose of this interrupt is to toggle PA4 every 1 s or
		 every 244 interrupts.  Thus, a global variable is used
		 to keep a count of the number of rti interrupts that 
		 have occured.  The interrupt only toggles the interrupt
		 when the count has been reduced from 244 to 0.
Inputs: None
Outputs: None
**************************************************************/
#pragma interrupt_handler	RTI_ISR
void RTI_ISR(void)
{
	//printf("\nRTI_ISR entered");
	TFLG2 = 0x40;
	count = count - 1;
	if (count == 0)
	{
   		PORTA = (PORTA ^ 0x10);   /*Toggle PA4*/
   		count = 120;
	}

	//asm(" pulx");
	//asm(" rti");
}

/*************************************************************
Function: Main
Purpose: Main first intialiazes all the IC,and RTI interrupts.
		 It then intializes the SPI communication channel. It then
		 goes into a infinite loop writing to the SPDR if the
		 appropriate status variables are set.
		 
Inputs: None
Outputs: None
**************************************************************/

void main(void)
{
	asm("SEI");
	TMSK1 = 0x06; /*enable IC1 and IC2 interrupts*/
	TFLG1 = 0x06; /*Clear IC1F and IC2F*/
	TCTL2 = 0x3C; /*Set IC1 and IC2 interrupts on any edge*/

	TMSK2 = (TMSK2 | 0x40); /*Enable RTI Interrupt*/
	TFLG2 = (TFLG2 | 0x40); /*Clear the RTIF */
	PACTL = (PACTL & 0x03); /*Set RTI Interrupt rate for T=4.096 ms*/

	SPCR = 0x50;	  		   /*Intialize the SPI*/
	PORTD = (PORTD | 0x20); /*Enable Device as the master*/
	DDRD = (DDRD | 0x38);   /*Initialize PortD*/

	RTIvector = &RTI_ISR;
	TOC2vector = &T0C2_ISR;
	TOC1vector = &TOC1_ISR;
	TIC2vector = &TIC2_ISR; 
	TIC1vector = &TIC1_ISR;	

	asm("CLI");

	printf("\nThe start of main");

	while(1)
	{
		printf("\nstart of while loop");
		
		if (statusA == 1)
		{
			SPDR = 0x00;
			while ((SPSR & 0x80)==0)
			{
				dummy = 1;
			}
			dummy = SPSR;
			dummy = SPDR;
			statusA = 0;
		}
		
		if (statusB == 1)
		{
			SPDR = 0x01;
			while ((SPSR & 0x80)==0)
			{
				dummy = 1;
			}
			dummy = SPSR;
			dummy = SPDR;
			statusB = 0;
		}
	}
}