Display temperature on Graphic Liquid Crystal Display using PIC16F877A Microcontroller

Hello everybody welcome back . Today I’m gonna tell how you can display temperature with bar graph on Graphic LCD using PIC microcontroller . The project is very simple to understand if you have concept of

Graphic LCD .The program in this project is written in C and Assembly level language &  the compiler used to write the C code is mikroC PRO for PIC V. 7.1.0 .You can download complete project (C and Asm file with proteus8 file ) from this link temperature on GLCd . 

Graphical Liquid Crystal (GLCD)

Graphical lcds are different from the ordinary alphanumeric  lcds, like 16×1 16×2 16×4 20×1 20×2 etc. They (ordinary) can print only characters or custom made characters. They have a fixed size for displaying a character normally 5×7 or 5×8 matrix. Where as in graphical lcd we have 128×64=8192 dots each dot can be lit up as our wish or we can make pixels with 8 dots ie. 8192/8=1024 pixels. We can design a character in a size which we need. More over we can make a picture on a graphical LCD as well. you can learn more about this LCD on this link Graphic LCD

LM35 Temperature Sensor

The LM35 temperature sensor is a semiconductor sensor. It is available in integrated circuit (IC) form. It has 3 pins and the IC is as shown below.

Display temperature on Graphic Liquid Crystal Display using PIC16F877A microcontroller explained1
Working Principle of temperature sensor :

VT = kT/q

Features of LM35:

  • Calibrated directly in Celsius scale ( Centigrade)
  • Linear +10 mV/0C scale factor
  • 50C Ensured Accuracy (at 250C)
  • Works for -550C to 1500C
  • Operates in the range of 4V to 30V
  • Less than 60µA design drain current
  • Low impedance output, 0.1Ω for 1-mA load
  • Low self heating, 0.80C in still air

Display temperature on Graphic Liquid Crystal Display using PIC16F877A Microcontroller (Code)


// Glcd module connections
char GLCD_DataPort at PORTD;
sbit GLCD_CS1 at RC0_bit;
sbit GLCD_CS2 at RC1_bit;
sbit GLCD_RS at RB3_bit;
sbit GLCD_RW at RB4_bit;
sbit GLCD_EN at RB5_bit;
sbit GLCD_RST at RE2_bit;
sbit GLCD_CS1_Direction at TRISC0_bit;
sbit GLCD_CS2_Direction at TRISC1_bit;
sbit GLCD_RS_Direction at TRISB3_bit;
sbit GLCD_RW_Direction at TRISB4_bit;
sbit GLCD_EN_Direction at TRISB5_bit;
sbit GLCD_RST_Direction at TRISE2_bit;
// End Glcd module connections
char txt[4];
unsigned tmp;
void main() {
Glcd_Init();
Glcd_Fill(0);
ADC_Init();
while(1){
tmp = ADC_Read(0);
tmp = tmp/2.05;
ByteToStr(tmp, txt);
Glcd_Write_Text("o", 60,0, 1);
Glcd_Write_Text(txt, 35,1, 1);
Glcd_Write_Text("TEMP =", 0,1, 1);
Glcd_Write_Text("C ", 70,1, 1);
if (tmp>20) {Glcd_Box(10, 50, 20, 70, 1); }
if (tmp<20) {Glcd_Box(10,50, 20, 70, 0); } if (tmp>40) {Glcd_Box(20, 45, 30, 70, 1); }
if (tmp<40) {Glcd_Box(20, 45, 30, 70, 0); } if (tmp>60) {Glcd_Box(30, 40, 40, 70, 1); }
if (tmp<60) {Glcd_Box(30, 40, 40, 70, 0); } if (tmp>80) {Glcd_Box(40, 35, 50, 70, 1); }
if (tmp<80) {Glcd_Box(40, 35, 50, 70, 0); } if (tmp>100) {Glcd_Box(50, 30, 60, 70, 1); }
if (tmp<100) {Glcd_Box(50, 30, 60, 70, 0); } if (tmp>115) {Glcd_Box(60, 25, 70, 70, 1); }
if (tmp<115) {Glcd_Box(60, 25, 70, 70, 0); } if (tmp>130) {Glcd_Box(70, 20, 80, 70, 1); }
if (tmp<130) {Glcd_Box(70, 20, 80, 70, 0); } if (tmp>140) {Glcd_Box(80, 15, 90, 70, 1); }
if (tmp<140) {Glcd_Box(80, 15, 90, 70, 0); } if (tmp>145) {Glcd_Box(90, 10, 100, 70, 1); }
if (tmp<145) {Glcd_Box(90, 10, 100, 70, 0); }
}
}

Display temperature on Graphic Liquid Crystal Display using PIC16F877A Microcontroller (Schematic Diagram)

Display temperature on Graphic Liquid Crystal Display using PIC16F877A microcontroller explained
PROTEUS SCHAMATIC DIAGRAM WITH ANIMATION

Short Description

The code is very easy to understand . First we have defined Control and DATA pins of graphical LCD to PIC microcontroller . Then after we have displayed some text using function Glcd_Write_Text(“”, ,,); .Since we cannot write box using Glcd_Write_Text(); function we have to make our own box using the function Glcd_Box(x,y,-x,-y,on/off). These box are made to respective temperature and the box is used to represent the temperature . Thats all concept behind this project .
If you have any question about this project please comment below , if you like this project please share this .

About The Author

Ibrar Ayyub

I am an experienced technical writer with a Master's degree in computer science from BZU Multan University. I have written for various industries, mainly home automation, and engineering. I have a clear and simple writing style and am skilled in using infographics and diagrams. I am a great researcher and is able to present information in a well-organized and logical manner.

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