/*******************************************************
*Authors: Sami Lasassmeh.
*Date: 12/18/2003
*Description: C-code to generate different types of square waves to meet the 
*project requirements using timers.
 *************************************************************/

#include "skp26.h"
#include "sfr262.h"

void main(void);
void display_ad_value(void);

const char message[6][9]={//array of characters to appear on the display.
{"Welcome "},{"ECGR6090"},
{"halassal"},{"salsassm"}};

/*connect switches and LEDs to I/O ports*/
#define LED_R p7_0
#define LED_Y p7_1
#define LED_G p7_2
#define SW2 p10_5
#define SW3 p10_6
#define SW4 p10_7
unsigned long int m=0;//used to generate a delay and solve the bouncing 
			//problem
int cnt=0;
int A1_done=0;//variable to set by an ISR.
int A4_done=0;//variable to set by an ISR.
const int sws_array[3][8]={//3 arrays holding the codes for 3 switches.
{1,0,1,1,0,1,1,0},
{1,0,1,0,1,0,1,0},
{1,0,1,1,1,0,1,0}};

void A0A1A2A4_init(void){//function to initialize timers.
ta0=0x014D;//load timer A0 by this value to generate 30khz.
ta1=0x0027;// load timer A by this value to generate 20 pulses at 30khz.
ta4=0x0253;// load timer A4 by this value to shutdown for 10msec.
ta2=0x014D;// load timer A2 by this value to generate 30khz when it is 
		//triggered.
ta0mr=0x04;//Timer A0 work in timer mode.
ta1mr=0x0D;// Timer A1 work in event counter mode.
ta4mr=0x0D;// Timer A4 work in event counter mode.
ta2mr=0x04;// Timer A2 work in timer mode.
udf=0x00;//down count.
trgsr=0xC2;//A0 trigger A1 and A4
asm("FCLR I");//disable interrupts
/*assign priorities*/
ta0ic=0x03;
ta1ic=0x05;
ta4ic=0x06;
ta2ic=0x02;
tabsr=0x00;
asm("FSET I");//enable interrupts.
}

void snd_fun(void){//function to meet the requirements for each pressed switch.
   if(!SW2){//switch2 is pressed
	LED_Y=0;
	m=0;
	do{m=m+1;//delay to solve bouncing problem.
	}while(m<=250000);
	for(cnt=0;cnt<=7;cnt++){
	   switch(sws_array[0][cnt]){//switch if the bit is 0 or 1.
 	     case 1:tabsr=0x17;//if it is 1, start all the timers
		while(!A1_done);//wait for 20 pulses to be generated
		tabsr=tabsr&0x13;//stop A2
		while(!A4_done);//shutdown for 9.34msec.
		tabsr=0x00;//stop all timers
/*reinitialize all variables and registers*/
		A1_done=0;
		A4_done=0;
		ta0=0x014D;
		ta1=0x0027;
		ta4=0x0253;
		ta2=0x014D;
		break;
	     case 0:tabsr=0x13;//if it is 0, start A0, A1, and A4.
		while(!A4_done);//shutdown for 10msec.
		/*reinitialize all varialbles*/
		tabsr=0x00;
		A1_done=0;
		A4_done=0;
		ta0=0x014D;
		ta1=0x0027;
		ta4=0x0253;
		ta2=0x014D;
		break;
		}
	}
   }
   if(!SW3){//switch3 is pressed
	LED_Y=0;
	m=0;
	do{m=m+1;//delay to solve bouncing problem.
	}while(m<=250000);
	for(cnt=0;cnt<=7;cnt++){
	   switch(sws_array[1][cnt]){//switch if the bit is 0 or 1.
 	     case 1:tabsr=0x17;//if it is 1, start all the timers
		while(!A1_done);//wait for 20 pulses to be generated
		tabsr=tabsr&0x13;//stop A2
		while(!A4_done);//shutdown for 9.34msec.
		tabsr=0x00;//stop all timers
/*reinitialize all variables and registers*/
		A1_done=0;
		A4_done=0;
		ta0=0x014D;
		ta1=0x0027;
		ta4=0x0253;
		ta2=0x014D;
		break;
	     case 0:tabsr=0x13;//if it is 0, start A0, A1, and A4.
		while(!A4_done);//shutdown for 10msec.
		/*reinitialize all varialbles*/
		tabsr=0x00;
		A1_done=0;
		A4_done=0;
		ta0=0x014D;
		ta1=0x0027;
		ta4=0x0253;
		ta2=0x014D;
		break;
		}
	}
   }

   if(!SW4){//switch4 is pressed
	LED_Y=0;
	m=0;
	do{m=m+1;//delay to solve bouncing problem.
	}while(m<=250000);
	for(cnt=0;cnt<=7;cnt++){
	   switch(sws_array[2][cnt]){//switch if the bit is 0 or 1.
 	     case 1:tabsr=0x17;//if it is 1, start all the timers
		while(!A1_done);//wait for 20 pulses to be generated
		tabsr=tabsr&0x13;//stop A2
		while(!A4_done);//shutdown for 9.34msec.
		tabsr=0x00;//stop all timers
/*reinitialize all variables and registers*/
		A1_done=0;
		A4_done=0;
		ta0=0x014D;
		ta1=0x0027;
		ta4=0x0253;
		ta2=0x014D;
		break;
	     case 0:tabsr=0x13;//if it is 0, start A0, A1, and A4.
		while(!A4_done);//shutdown for 10msec.
		/*reinitialize all varialbles*/
		tabsr=0x00;
		A1_done=0;
		A4_done=0;
		ta0=0x014D;
		ta1=0x0027;
		ta4=0x0253;
		ta2=0x014D;
		break;
		}
	}
   }
 LED_Y=1;
}

#pragma INTERRUPT A1_isr
void A1_isr(void){
   A1_done=1;//set this variable after generating 20 pulses.
}

#pragma INTERRUPT A4_isr
void A4_isr(void){
   A4_done=1;//set this variable after 10msec.
}

void init_switches(void){
   pd10_5=pd10_6=pd10_7=0;//set ports as inputs
}

void init_LEDs(void){
   pd7_0=pd7_1=pd7_2=1;//set ports as outputs.
}

void main(void){//main function
   init_disp();//initialize the display
   display(0,message[0]);
   display(1,message[1]);
   init_switches();//initialize switches.
   init_LEDs();//initialize LEDs
   A0A1A2A4_init();//initialize timers
   ALL_LED_OFF//turn all LEDs off
   while(1){//infinite loop waiting calling the snd_fun function.
    snd_fun();
   }
}