5x7matrix_main.c

This is the source code for 5x7 Matrix display developed using PIC Microcontroller

	SPPCFG = 0;
	DECODER_1E = 1;		//Disable Both Decoders
	DECODER_2E = 1;	
}

//This Function will read the data from External EEPROM to the internal RAM memory

void Fill_Buffer(unsigned short long int *addr,unsigned char bufptr)
{
	unsigned char addrl;
	unsigned char addrh;
	unsigned char addru;
	ram unsigned char i,j,k;
	ram unsigned char ttotal_segment;
	addrl = (unsigned char) *addr;
	addrh = (unsigned char) (*addr>>8);
	addru = (unsigned char) (*addr>>16);

	Ex_EEPROM_Block_Select(addru);	//selects Block of the External EEPROM
	
	if(Time == 0xAA)				//Display Message and Time Simultaneously
		ttotal_segment = Total_Segment - 5;
	else if(Time == 0x55)			//Display Time Only
	{
		for(i=0;i<(Total_Segment*5);i++)
			Buffer[i] = 0;
		ttotal_segment = 0;	
		bufptr = bufptr+4;
	}
	else
		ttotal_segment = Total_Segment;
	
	for(i=0;i<ttotal_segment;i++)		//Read the amount data equal to total segment
	{
		INTCONbits.GIE = 0;
		i2c_start();
		i2c_write(eeprom_write_command);
		i2c_write(addrh);
		i2c_write(addrl);
		i2c_restart();
		i2c_write(eeprom_read_command);
		Buffer[bufptr] = i2c_read(1);
		i2c_stop();
		bufptr++;
		INTCONbits.GIE = 1;
		STATUSbits.C = 0;
		addrl+=5;
		if(STATUSbits.C)
		{
			STATUSbits.C = 0;
			addrh++;
			if(STATUSbits.C)
			{	
				addru++;
				Ex_EEPROM_Block_Select(addru);
			}
		}
	}

	if(Time == 0xAA)			//Fill the Time Data in the Buffer
	{
		k = tcount;
		for(j=0;j<5;j++)
		{
			Buffer[bufptr] = RTC_Buffer[k];
			bufptr++;
			k +=5;
		}
		tcount++;
	}
	else if(Time == 0x55)
	{	
		k = tcount;
		i = 4;
		for(j=0;j<8;j++)
		{
			Buffer[bufptr] = RTC_Buffer[k];
			bufptr++;
			k+=5;
		}
		tcount++;
	}
}

//This function fill the Readed data from the EEPROM into the latch

void Load_Latch(unsigned char bptr)
{
	unsigned char i;
	
	if(Total_Segment < 17)		//Default
	{
		DECODER_1E = 0;
		DECODER_2E = 1;
		for(i=0;i<Total_Segment;i++)
		{
			DECODER_INPUT = ((i<<4) & 0xF0) | ((LATB & 0x0F));
		//	delay_us(1);
			LATCH_DATA = Buffer[bptr];
			bptr++;
		}
	}
	else if(Total_Segment < 25)
	{
		DECODER_1E = 0;
		DECODER_2E = 1;
		for(i=0;i<16;i++)
		{
			DECODER_INPUT = ((i<<4) & 0xF0) | ((LATB & 0x0F));
		//	delay_us(1);
			LATCH_DATA = Buffer[bptr];
			bptr++;
		}
		DECODER_1E = 1;
		LATCH_DATA = 0;
		DECODER_2E = 0;
		for(i=16;i<24;i++)
		{
			DECODER_INPUT = ((i<<4) & 0xF0) | ((LATB & 0x0F));
		//	delay_us(1);
			LATCH_DATA = Buffer[bptr];
			bptr++;
		}
	}
	else 
	{
		DECODER_1E = 0;
		DECODER_2E = 1;
		
		for(i=0;i<16;i++)
		{
			DECODER_INPUT = ((i<<4) & 0xF0) | ((LATB & 0x0F));
		//	delay_us(1);
			LATCH_DATA = Buffer[bptr];
			bptr++;
		}
		DECODER_1E = 1;
		DECODER_2E = 0;
		for(i=16;i<32;i++)
		{
			DECODER_INPUT = ((i<<4) & 0xF0) | ((LATB & 0x0F));
		//	delay_us(1);
			LATCH_DATA = Buffer[bptr];
			bptr++;
		}
	}
	DECODER_1E = 1;
	DECODER_2E = 1;
}

//New Message Service routine
//Get the font value followed by Data to display in ASCII format
//Every charater controller will send the ackowledgement character 'P'
//To Specify the End of Message PC must send 0x00 data to microcontroller
//and the controller will acknowledge the termination by sending the character 'O'
	 
void New_Message()
{
	ram unsigned char l,h,u,text,i,j,k,al,ah,font,width;
	ram unsigned int uhl,ruhl,loc;
	far rom unsigned int *ptr;

	Fill_PrePost_Zero(0,0);
	ah = 0;
	al = Total_Segment*5;
	putc_ram('F');
	font = getc_ram();	
	while((text = getc_ram()) != 0x00)
	{
		text = text - 30;

		ptr = &LukUpfontstart[font-1][text];
		loc = *ptr;
			
		putc_ram((unsigned char)loc);
		putc_ram((unsigned char)loc>>8);

		romptr = &LukUpfontwidth[font-1][text];	
		width = *romptr;

		putc_ram(width);		

		romptr = &(*LukUpfont[font-1]) + loc;	
			
		for(i=0;i<width;i++)
		{
			Buffer[i] =*romptr;
			romptr++;
		}

		for(i=0;i<width;i++)
			putc_ram(Buffer[i]);
			
		for(i=0;i<width;i++)
		{
			i2c_start();
			i2c_write(EEPROM_WRITE);
			i2c_write(ah);
			i2c_write(al);
			i2c_write(Buffer[i]);
			i2c_stop();
			al++;
			if(al == 0)
				ah++;
			delay_ms(10);
		}
		
		putc_ram('P');
	
	}
	EEPROM_Write(Total_BytesL,al);
	EEPROM_Write(Total_BytesH,ah);
	EEPROM_Write(Total_BytesU,0);
	Fill_PrePost_Zero(al,ah);
	EEPROM_Write(Start_addressL,0);
	EEPROM_Write(Start_addressH,0);
	EEPROM_Write(Start_addressU,0);	
	putc_ram('O');
	while(!TXSTAbits.TRMT);
}

//if Time display is enabled 
//This function will fill the buffer with the time values

void Time_Display()
{
	unsigned char i,tmin,thour;
	far rom unsigned int *ptr;
	ram unsigned int loc;

	i2c_start();				//Read the values from RTC
	i2c_write(RTC_WRITE);
	i2c_write(0);
	i2c_restart();
	i2c_write(RTC_READ);
	sec = i2c_read(0);
	min = i2c_read(0);
	hour = i2c_read(1);
	i2c_stop();

	i= Calculate_hour();		//Convert the hour data into segment display data

	RTC_Buffer[i++] = 0x22;
	RTC_Buffer[i++] = 0x00;

	i = Calculate_min(i);		//Convert the min data into segmnt data
	
	if(Time == 0x55)			//if  its time only display its convert the sec data corresponding to display in segment
	{	
		RTC_Buffer[i++] = 0x22;
		RTC_Buffer[i++] = 0x00;
		Calculate_sec(i);
	}
	tcount = 0;
}

unsigned char Calculate_hour(void)
{
	unsigned char i,thour;
	far rom unsigned int *ptr;
	ram unsigned int loc;

	hour = hour & 0x3F;
	thour = (hour>>4) + 0x30;
	hour = (hour & 0x0F) + 0x30; 

	ptr = &LukUpfontstart[0][thour - 30];
	loc = *ptr;
	romptr = &(*LukUpfont[0]) + loc;	
	for(i=0;i<6;i++)
	{
		RTC_Buffer[i] =*romptr;
		romptr++;
	}

	ptr = &LukUpfontstart[0][hour - 30];
	loc = *ptr;
	romptr = &(*LukUpfont[0]) + loc;	
	for(;i<12;i++)
	{
		RTC_Buffer[i] =*romptr;
		romptr++;
	}
	return i;
}

unsigned char Calculate_min(unsigned char i)
{
	unsigned char tmin,ttt;
	far rom unsigned int *ptr;
	ram unsigned int loc;
	ttt = i+6;
	tmin = (min>>4) + 0x30;	
	min = (min & 0x0F) + 0x30;

	ptr = &LukUpfontstart[0][tmin - 30];
	loc = *ptr;
	romptr = &(*LukUpfont[0]) + loc;	
	for(;i<ttt;i++)
	{
		RTC_Buffer[i] =*romptr;
		romptr++;
	}
	ttt+=6;
	ptr = &LukUpfontstart[0][min - 30];
	loc = *ptr;
	romptr = &(*LukUpfont[0]) + loc;	
	for(;i<ttt;i++)
	{
		RTC_Buffer[i] =*romptr;
		romptr++;
	}
	return i;
}

void Calculate_sec(unsigned char i)
{
	unsigned char tsec,ttt;
	far rom unsigned int *ptr;
	ram unsigned int loc;
	ttt = i+6;
	tsec = (sec>>4) + 0x30;	
	sec = (sec & 0x0F) + 0x30;

	ptr = &LukUpfontstart[0][tsec - 30];
	loc = *ptr;
	romptr = &(*LukUpfont[0]) + loc;	
	for(;i<ttt;i++)
	{
		RTC_Buffer[i] =*romptr;
		romptr++;
	}
	ttt+=6;
	ptr = &LukUpfontstart[0][sec - 30];
	loc = *ptr;
	romptr = &(*LukUpfont[0]) + loc;	
	for(;i<ttt;i++)
	{
		RTC_Buffer[i] =*romptr;
		romptr++;
	}
}