Engineering Calculators

Engineering Calculators

Good electronics Book Notes Tutorials

Digital Voltage Temperature And Frequency Meter Using PIC 16F877

Digital Voltage Temperature And Frequency Meter Using PIC 16F877

Voltage meter

Volt meter can measure dc voltages up to 50v. 5V is the maximum voltage can handle PIC microcontroller, as it is voltage divider (10K,1.1K) use for convert 50V to 5V . 5v zener diode use for safety of PIC microcontroller analog input pin.

Temperature meter

Temperature meter can use between 0⁰C to 150⁰C. But LM35 sensor can use between -55⁰C to 150⁰C. Sensor’s resistant is changing opposite to temperature, as it is maximum temperature gives maximum voltage output(5v) and minimum temperature gives minimum voltage output(0v).

Frequency meter

Theoretically, frequency meter can use up to 65KHz, that is because this circuit made by using Timer 1(16bit) of PIC microcontroller.

// LCD module connections
sbit LCD_RS at RB4_bit;
sbit LCD_EN at RB5_bit;
sbit LCD_D4 at RB0_bit;
sbit LCD_D5 at RB1_bit;
sbit LCD_D6 at RB2_bit;
sbit LCD_D7 at RB3_bit;

sbit LCD_RS_Direction at TRISB4_bit;
sbit LCD_EN_Direction at TRISB5_bit;
sbit LCD_D4_Direction at TRISB0_bit;
sbit LCD_D5_Direction at TRISB1_bit;
sbit LCD_D6_Direction at TRISB2_bit;
sbit LCD_D7_Direction at TRISB3_bit;
// End LCD module connections

unsigned short cnt;
unsigned int freq_result;
int x, y, t;

// Define Messages
char message1[] = "      Hz  /65KHz";
char message2[] = "FERQUANCY METER";
char Message4[] = "VOLTAGE METER";
char Message5[] = "/MAX:50V";
char Message8[] = "TEMPERATURE ";
unsigned int ADC_Value, DisplayVolt;
unsigned int tempinF, tempinC;
unsigned long temp_value;
char *volt = "00.0";
char *freq = " 0000";
char *tempC = "000.0";
char *tempF = "000.0";

void Display_Freq(unsigned int freq2write) {

  freq[0] = (freq2write/10000)%10 + 48;
  freq[1] = (freq2write/1000)%10 + 48;
  freq[2] = (freq2write/100)%10 + 48;
  freq[3] = (freq2write/10)%10 + 48;    // Extract tens digit
  freq[4] =  freq2write%10     + 48;    // Extract ones digit

 Lcd_Out(2, 2, freq);                   // Display Frequency on LCD
}

void Display_Volt(unsigned int volts2write) {

  volt[0] =  volts2write/1000 + 48;
  volt[1] = (volts2write/100)%10 + 48;
  volt[3] = (volts2write/10)%10 + 48;

 Lcd_Out(2, 2, volt);                   // Display Voltage on LCD
}

void Display_Temperature() {
 if (tempinC/10000)
 tempC[0] = tempinC/10000 + 48;
 else
 tempC[0] = ' ';
 tempC[1] = (tempinC/1000)%10 + 48;
 tempC[2] = (tempinC/100)%10 + 48;
 tempC[4] = (tempinC/10)%10 + 48;
 Lcd_Out(2, 1, tempC);
 if (tempinF/10000)
 tempF[0] = tempinF/10000 + 48;
 else
 tempF[0] = ' ';
 tempF[1] = (tempinF/1000)%10 + 48;
 tempF[2] = (tempinF/100)%10 + 48;
 tempF[4] = (tempinF/10)%10 + 48;
 Lcd_Out(2, 10, tempF);
}

void main() {
  PORTB = 0;                            // Initialise PORTB
  TRISB = 0b01000000;                   // PORTB is output
  TRISA = 0b00001101;                   // PORTA All Outputs, Except RA0,RA3 and RA2
  TRISD = 0x0F;
  TRISC = 0x01;
  T1CON = 3;                            // Timer1 on, external input RC0
  TMR1IF_bit = 0;                       // clear TMR1IF
  TMR1H = 0x00;                         // Initialize Timer1 register
  TMR1L = 0x00;                         // Initialize Timer1 register
  cnt =   0;                            // initialize cnt
  Lcd_Init();                           // Initialize LCD
  ADCON0 = 0b00010000;                  // Analog channel select
  ADCON1 = 0x00;                        // Reference voltage is Vdd
  CMCON = 0x07 ;                        // Disable comparators
  Lcd_Cmd(_LCD_CURSOR_OFF);             // Cursor off
  x=1, y=0, t=1;
  do
  {
    temp_value = ADC_Read(0);
    temp_value = temp_value*56.238;
    tempinC = temp_value;
    tempinF = 9*tempinC/5 + 3200;
    ADC_Value = ADC_Read(2);
    TMR1H = 0;                             // reset high byte of timer 1 (takes effect when low byte written)
    TMR1L = 0;                             // reset low byte of timer 1 (also loads in high byte now)
    Delay_ms(500);  // Delay 1 Sec
    freq_result = TMR1L;                   // get low byte of timer 1 count (and read high byte to buffer)
    freq_result += TMR1H*256;              // add in the high byte from buffer
    freq_result *= 2.033;

     if(PORTD.B0==0 || x==0 )
      {
      x=0, y=1, t=1;
      PORTC.B1=1;
      PORTC.B2=0;
      PORTC.B3=0;
      PORTC.B4=0;
      Lcd_Cmd(_LCD_CLEAR);                  // CLEAR display
      Lcd_Cmd(_LCD_CURSOR_OFF);             // Cursor off
      Lcd_Out(2,1,message1);                // Write message1 in 1st row
      Lcd_Out(1,2,message2);
      Display_Freq(freq_result);            // show the Frequancy on LCD
      }
      if(PORTD.B1==0)
      {
      PORTC.B4=1;
      Lcd_Out(1,1,"p");
      x=1, y=1, t=1;
      }
      else{}
      if(PORTD.B2==0 || y==0 )
      {
      PORTC.B1=0;
      PORTC.B2=1;
      PORTC.B3=0;
      PORTC.B4=0;
      y=0, x=1, t=1;
      Lcd_Cmd(_LCD_CLEAR);                      // CLEAR display
      Lcd_Cmd(_LCD_CURSOR_OFF);                 // Cursor off
      Lcd_Out(1,3,Message4);
      Lcd_Out(2,9,Message5);
      Lcd_Chr(2,6,'V');
      DisplayVolt = ADC_Value * 4.94471;
      Display_Volt(DisplayVolt);                // show the Voltage on LCD
      }
      else{}
      if(PORTD.B3==0 || t==0)
      {
      PORTC.B1=0;
      PORTC.B2=0;
      PORTC.B3=1;
      PORTC.B4=0;
      y=1, x=1, t=0;
      Lcd_Cmd(_LCD_CLEAR);                     // CLEAR display
      Lcd_Cmd(_LCD_CURSOR_OFF);                // Cursor off
      Lcd_Out(1,4,message8);
      Lcd_Chr(2,6,223);
      Lcd_Chr(2,15,223);
      Lcd_Chr(2,7,'C');
      Lcd_Chr(2,16,'F');
      Display_Temperature();                  // show the Temp on LCD
      }
      else{}
  }
  while(1);                                   // Infinite loop
}

Download Below
Click

Digital Voltage Temperature And Frequency Meter Using PIC 16F877

Digital Voltage Temperature And Frequency Meter Using PIC 16F877

Voltage meter

Temperature meter

Frequency meter

Theoretically, frequency meter can use up to 65KHz, that is because this circuit made by using Timer 1(16bit) of PIC microcontroller.

// LCD module connections
sbit LCD_RS at RB4_bit;
sbit LCD_EN at RB5_bit;
sbit LCD_D4 at RB0_bit;
sbit LCD_D5 at RB1_bit;
sbit LCD_D6 at RB2_bit;
sbit LCD_D7 at RB3_bit;

sbit LCD_RS_Direction at TRISB4_bit;
sbit LCD_EN_Direction at TRISB5_bit;
sbit LCD_D4_Direction at TRISB0_bit;
sbit LCD_D5_Direction at TRISB1_bit;
sbit LCD_D6_Direction at TRISB2_bit;
sbit LCD_D7_Direction at TRISB3_bit;
// End LCD module connections

unsigned short cnt;
unsigned int freq_result;
int x, y, t;

// Define Messages
char message1[] = "      Hz  /65KHz";
char message2[] = "FERQUANCY METER";
char Message4[] = "VOLTAGE METER";
char Message5[] = "/MAX:50V";
char Message8[] = "TEMPERATURE ";
unsigned int ADC_Value, DisplayVolt;
unsigned int tempinF, tempinC;
unsigned long temp_value;
char *volt = "00.0";
char *freq = " 0000";
char *tempC = "000.0";
char *tempF = "000.0";

void Display_Freq(unsigned int freq2write) {

  freq[0] = (freq2write/10000)%10 + 48;
  freq[1] = (freq2write/1000)%10 + 48;
  freq[2] = (freq2write/100)%10 + 48;
  freq[3] = (freq2write/10)%10 + 48;    // Extract tens digit
  freq[4] =  freq2write%10     + 48;    // Extract ones digit

 Lcd_Out(2, 2, freq);                   // Display Frequency on LCD
}

void Display_Volt(unsigned int volts2write) {

  volt[0] =  volts2write/1000 + 48;
  volt[1] = (volts2write/100)%10 + 48;
  volt[3] = (volts2write/10)%10 + 48;

 Lcd_Out(2, 2, volt);                   // Display Voltage on LCD
}

void Display_Temperature() {
 if (tempinC/10000)
 tempC[0] = tempinC/10000 + 48;
 else
 tempC[0] = ' ';
 tempC[1] = (tempinC/1000)%10 + 48;
 tempC[2] = (tempinC/100)%10 + 48;
 tempC[4] = (tempinC/10)%10 + 48;
 Lcd_Out(2, 1, tempC);
 if (tempinF/10000)
 tempF[0] = tempinF/10000 + 48;
 else
 tempF[0] = ' ';
 tempF[1] = (tempinF/1000)%10 + 48;
 tempF[2] = (tempinF/100)%10 + 48;
 tempF[4] = (tempinF/10)%10 + 48;
 Lcd_Out(2, 10, tempF);
}

void main() {
  PORTB = 0;                            // Initialise PORTB
  TRISB = 0b01000000;                   // PORTB is output
  TRISA = 0b00001101;                   // PORTA All Outputs, Except RA0,RA3 and RA2
  TRISD = 0x0F;
  TRISC = 0x01;
  T1CON = 3;                            // Timer1 on, external input RC0
  TMR1IF_bit = 0;                       // clear TMR1IF
  TMR1H = 0x00;                         // Initialize Timer1 register
  TMR1L = 0x00;                         // Initialize Timer1 register
  cnt =   0;                            // initialize cnt
  Lcd_Init();                           // Initialize LCD
  ADCON0 = 0b00010000;                  // Analog channel select
  ADCON1 = 0x00;                        // Reference voltage is Vdd
  CMCON = 0x07 ;                        // Disable comparators
  Lcd_Cmd(_LCD_CURSOR_OFF);             // Cursor off
  x=1, y=0, t=1;
  do
  {
    temp_value = ADC_Read(0);
    temp_value = temp_value*56.238;
    tempinC = temp_value;
    tempinF = 9*tempinC/5 + 3200;
    ADC_Value = ADC_Read(2);
    TMR1H = 0;                             // reset high byte of timer 1 (takes effect when low byte written)
    TMR1L = 0;                             // reset low byte of timer 1 (also loads in high byte now)
    Delay_ms(500);  // Delay 1 Sec
    freq_result = TMR1L;                   // get low byte of timer 1 count (and read high byte to buffer)
    freq_result += TMR1H*256;              // add in the high byte from buffer
    freq_result *= 2.033;

     if(PORTD.B0==0 || x==0 )
      {
      x=0, y=1, t=1;
      PORTC.B1=1;
      PORTC.B2=0;
      PORTC.B3=0;
      PORTC.B4=0;
      Lcd_Cmd(_LCD_CLEAR);                  // CLEAR display
      Lcd_Cmd(_LCD_CURSOR_OFF);             // Cursor off
      Lcd_Out(2,1,message1);                // Write message1 in 1st row
      Lcd_Out(1,2,message2);
      Display_Freq(freq_result);            // show the Frequancy on LCD
      }
      if(PORTD.B1==0)
      {
      PORTC.B4=1;
      Lcd_Out(1,1,"p");
      x=1, y=1, t=1;
      }
      else{}
      if(PORTD.B2==0 || y==0 )
      {
      PORTC.B1=0;
      PORTC.B2=1;
      PORTC.B3=0;
      PORTC.B4=0;
      y=0, x=1, t=1;
      Lcd_Cmd(_LCD_CLEAR);                      // CLEAR display
      Lcd_Cmd(_LCD_CURSOR_OFF);                 // Cursor off
      Lcd_Out(1,3,Message4);
      Lcd_Out(2,9,Message5);
      Lcd_Chr(2,6,'V');
      DisplayVolt = ADC_Value * 4.94471;
      Display_Volt(DisplayVolt);                // show the Voltage on LCD
      }
      else{}
      if(PORTD.B3==0 || t==0)
      {
      PORTC.B1=0;
      PORTC.B2=0;
      PORTC.B3=1;
      PORTC.B4=0;
      y=1, x=1, t=0;
      Lcd_Cmd(_LCD_CLEAR);                     // CLEAR display
      Lcd_Cmd(_LCD_CURSOR_OFF);                // Cursor off
      Lcd_Out(1,4,message8);
      Lcd_Chr(2,6,223);
      Lcd_Chr(2,15,223);
      Lcd_Chr(2,7,'C');
      Lcd_Chr(2,16,'F');
      Display_Temperature();                  // show the Temp on LCD
      }
      else{}
  }
  while(1);                                   // Infinite loop
}

Download Below
Click

Transformer Design Basics

Part 1.

Inverter Transformer ,stepUp transformer ,Step Down Transformer Desgin

Here trying provide some basics of transformer design and its tutorials with series of parts[posts] . Part 1 provide the basics steps.

Design Consideration

1. Power Rating

First we require what rate of transformer we require ,Here we need to decide which rate for example 1000Va ,1500va etc .

2.Step Down / Step Up Transformer

Here you should decide what type of transformer you required ,ie Is it step down / Step Up ?

It means that you decide the voltages of primary and secondary.Also decide the Frequency.

Eg: Primary -230V Secondary 12V Frequency 50Hz

2.Primary and Secondary Currents

Then You need to select the currents in each windings ie,Primary and Secondary winding.

Eg: if we selct 1000VA then the primary Current 1000/230=4.347.

The Secondary volt is 12V

then Secondary Current is 1000/12 = 83.333 =84Ampere.

2.Primary and Secondary coils wire diameter/size

Next we need to decide the coil diameter .It can be only select from a calculation as each coil has its own capability of current .As shown the table

2.Iorn Core Area

Iron Core area is selected in according to how much rating or how much power has been required .

Eg ; if we require 1000VA core Area required 32.cm^2 .[calculation will be provide following posts]

In according to How much core area we can select corresponding Bobbins .Because each type of Bobbins has their own Core Area .

Some of Bobbins Table as follows

Details design will be Continue

Transformer Design Basics

Part 1.

Inverter Transformer ,stepUp transformer ,Step Down Transformer Desgin

Here trying provide some basics of transformer design and its tutorials with series of parts[posts] . Part 1 provide the basics steps.

Design Consideration

1. Power Rating

First we require what rate of transformer we require ,Here we need to decide which rate for example 1000Va ,1500va etc .

2.Step Down / Step Up Transformer

Here you should decide what type of transformer you required ,ie Is it step down / Step Up ?

It means that you decide the voltages of primary and secondary.Also decide the Frequency.

Eg: Primary -230V Secondary 12V Frequency 50Hz

2.Primary and Secondary Currents

Then You need to select the currents in each windings ie,Primary and Secondary winding.

Eg: if we selct 1000VA then the primary Current 1000/230=4.347.

The Secondary volt is 12V

then Secondary Current is 1000/12 = 83.333 =84Ampere.

2.Primary and Secondary coils wire diameter/size

Next we need to decide the coil diameter .It can be only select from a calculation as each coil has its own capability of current .As shown the table

2.Iorn Core Area

Iron Core area is selected in according to how much rating or how much power has been required .

Eg ; if we require 1000VA core Area required 32.cm^2 .[calculation will be provide following posts]

In according to How much core area we can select corresponding Bobbins .Because each type of Bobbins has their own Core Area .

Some of Bobbins Table as follows

Details design will be Continue

Micro controller Based Password Lock

Password based Door locking system

This is a 8051 based security project, we can lock and unlock the door electronically. Electronic door locking systems are used in Bank lockers, home lockers, main doors and prison etc.,

Working: When we give correct UserID and Password then only we can UNLOCK and LOCK the door otherwise we can't operate it. If we entered correct userID and password it will show authenticated message on LCD screen otherwise Invalid userID or Access Denide. Then you can select one of the option LOCK DOOR and UNLOCK DOOR.

Here is the functional fl

ow chart

Here we are showing how door can be locked and unlocked mechanically and electrically with mechanical body of the door

case'1': when the door is locked

case'2':When the door is unlocked

NOTE: I haven't connected any motor driver here, but practically we can interconnect opto-coupler or motor driver H-bridge

Code




// Password based Door lock 
// modifying userID and Password
#include
sfr ROW=0x80;	//assigning PORT-0 to read rows
sfr COL=0xA0;	//assigning PORT-2 to read colomns
sfr ldata=0x90;	//assigning PORT-1 for LCD data
sbit rs=P3^0;
sbit rw=P3^1;
sbit en=P3^2;
sbit busy=P1^7;
sbit servo=P3^3;          //Output to motor
void lcdcmd(unsigned char value) ;
void lcddata(unsigned char value);
void lcdready(void)	   ;
void printstring(unsigned char ch[]) ;
void LCDclear(void);
void msdelay(unsigned int value)  ;
int keypad();
void timer(unsigned int msec);
void door_open(void);

void door_close(void);
unsigned char userID[5]={"9876"};
unsigned char password[5]={"1234"};
unsigned char update_1[5]={"0000"};
 unsigned char update_2[5]={"0000"};
 unsigned char x;
void main(void)
{ 
 unsigned int i,k;
 
 
  lcdcmd(0x38);
  lcdcmd(0x0F);
  lcdcmd(0x06);
  lcdcmd(0x01);
  //while(1){
  LCDclear();
  lcdcmd(0x80);
  while(1)
  {
  printstring("userID:");
  lcdcmd(0x87);
  
   i=0;
  do
  {
   update_1[i]=keypad();
   lcddata(update_1[i]);
   i++;
   }while(i!=4);
   i=0;
   if(update_1[0]==userID[0] && update_1[1]==userID[1] && update_1[2]==userID[2] && update_1[3]==userID[3] )
   {
 		 lcdcmd(0xC0);
 		 printstring("password:");
  		 lcdcmd(0xC9);
  
 		 do
 		 {
  			 update_1[i]=keypad();
  			 i++;
  			 lcddata('*');
  		 }while(i!=4);
		  if(update_1[0]==password[0] && update_1[1]==password[1] && update_1[2]==password[2] && update_1[3]==password[3] )
 		   {
		   LCDclear();
		   printstring("Authenticated");
		   msdelay(2000);
		   LCDclear();
		   lcdcmd(0x80);
		   printstring("1.Unlock Door");
		   lcdcmd(0xC0);
		   printstring("2.lock Door");

		   do
		   {
		    k=keypad();
			}while(k!='1' && k!='2' && k!='C');
		    switch(k)
			{
			 case '1' :while(1)
						 { 
						 door_open();
						if('2'==keypad())
						   door_close();
			 			if('C' ==keypad())
				 			{
				 				main();
							}	
						}
			 			break;
			case '2' : 	while(1)
						{
						 door_close();
						 if('1'==keypad())
						 door_open();
						if('C' ==keypad())
						 {
				 			main();
					    	}
						}
						break;
			case 'C' : main();
						break;
			default  :main();
					  break;
			}
		   }

		   else
		   {
		   LCDclear();
		   printstring("Access Denide");
		   msdelay(1000);
		   LCDclear();
		  
		   main();
		   }
 	
 }
 else
 {
  LCDclear();
  printstring("Invalid UserID");
  msdelay(1000);
  main();  		   
 }
 }
 }
 /* sending commands to  LCD display to act in command mode */ 
void lcdcmd(unsigned char value)
{
 lcdready();
 ldata=value;
 rs=0;
 rw=0;
 en=1;
 msdelay(10);
 en=0;
 }
 /* sending commnad to LCD to display characters*/
void lcddata(unsigned char value)
{
 lcdready();
 ldata=value;
 rs=1;
 rw=0;
 en=1;
 msdelay(10);
 en=0;
 }
 /* checking LCD buffer for free */
void lcdready(void)
{
 busy=1;
 rs=0;
 rw=1;
 if(busy==1)
  {
   en=0;
   msdelay(1);
   en=1;
   }
}

void printstring(unsigned char ch[])
{
 unsigned int i;
 for(i=0;ch[i]!='\0';i++)
 lcddata(ch[i]);
 }
/* generating delay*/
void msdelay(unsigned int value)
{
 unsigned int i,j;
 for(i=0;i for(j=0;j<100;j++);
 }
void LCDclear(void)
 {
  lcdcmd(0x01);
  }
int keypad() 
 {
   unsigned char dat[4][4]={'7','8','9','%',	 // assigning key matrix
                          '4','5','6','*',
						   '1','2','3','-',
						   'C','0','=','+'};
 unsigned char colloc,rowloc;
 COL=0xFF;
 ROW=0x00;
 rs=0;
 rw=0;
 en=0;
 busy=0;
 /* setting LCD screen*/ 
 ldata=0x00;
 lcdcmd(0x38);
 lcdcmd(0x0E);
  lcdcmd(0x06);

 while(1)
 {
/* reading character from keyboard */
   do
   {
    ROW=0x00;
   	colloc=COL;
	colloc&=0x0F;
	}while(colloc!=0x0F);
	do
	{
	 do
	 {
	  msdelay(25);
	  colloc=COL;
	  colloc&=0x0F;
	  }while(colloc==0x0F);
	  msdelay(25);
	  colloc=COL;
	  colloc&=0x0F;
	  }while(colloc==0x0F);
    while(1)
	{
	 ROW=0xFE;
	 colloc=COL;
	 colloc&=0x0F;
	 if(colloc!=0x0F)
	 { 
	  rowloc=0;
	  break;
	  }
	  ROW=0xFD;
	  colloc=COL;
	  colloc&=0x0F;
	   if(colloc!=0x0F)
	   {
	    rowloc=1;
		break;
		}
	  ROW=0xFB;
	  colloc=COL;
	  colloc&=0x0F;
	   if(colloc!=0x0F)
	   {
	    rowloc=2;
		break;
		}
	  ROW=0xF7;
	  colloc=COL;
	  colloc&=0x0F;
	if(colloc!=0x0F)
	  {  
	      rowloc=3;
	      break;
	    }
	   }
   if(colloc==0x0E)
   return(dat[rowloc][0]);
   else if(colloc==0x0D)
   return(dat[rowloc][1]);
   else if(colloc==0x0B)
   return(dat[rowloc][2]);
   else
    return(dat[rowloc][3]);
	}
	}
 void timer(unsigned int msec)     // Function for timer
{
unsigned int i;
for(i=0;i{
TMOD=0x20;         // Mode2
TH1=0xD1;
TL1=0xFF;

TR1=1;
while(TF1==0);
TF1=0;
TR1=0;
}
}

void door_open()
{
 unsigned int i;
servo=0;
//anticlockwise direction
		for(i=0;i<1;i++)
		{
			servo=1;
			timer(10);
			servo=0;
			timer(380);
		}
}
void door_close()
{
 unsigned int i;
servo=0;
//clockwise direction
		for(i=0;i<1;i++)
		{
			servo=1;
			timer(60);
			servo=0;
			timer(340);
		}
}

Electronics Online Calculator

Engineering Calculators

Electronics Online Calculator

Engineering Calculators

Electronics -Notes

Good electronics Book Notes Tutorials

Electronics -Notes

Good electronics Book Notes Tutorials

Digital Voltage Temperature And Frequency Meter Using PIC 16F877

Digital Voltage Temperature And Frequency Meter Using PIC 16F877

Transformer Design Basics

Transformer Design Basics

Design Consideration

Transformer Design Basics

Transformer Design Basics

Design Consideration

Micro controller Based Password Lock

Password based Door locking system

More Posts

Social Link

Report Abuse

Contributors

16x2 LCD Interfacing with STM32,STM32F103C6

Contact Form

Contact us

Follow Us

Comments

MKRdezign

Latest

Main Menu

Technology

Top Ads

RECENT COMMENTS

Subscribe Via Email

RECENT COMMENTS