Software Part of PC Based Temperature or multiple Sensor control.

#include<reg52.h>

 #define LINE1 0x80 #define LINE2 0xC0 

#define COLUMN1 0x00

 #define COLUMN2 0x01

 #define COLUMN3 0x02 

#define COLUMN4 0x03

 #define COLUMN5 0x04

 #define COLUMN6 0x05 

#define COLUMN7 0x06 

#define COLUMN8 0x07

 #define COLUMN9 0x08

#define COLUMN10 0x09

 #define COLUMN11 0x0a

#define COLUMN12 0x0b

#define COLUMN13 0x0c 

#define COLUMN14 0x0d 

#define COLUMN15 0x0e 

#define COLUMN16 0x0f

Sbit      LCD_RS=P0^0;

Sbit      LCD_RW=P0^1;

Sbit      LCD_EN=P0^2;

Sbit      LCD_BUSY=P1^7;

Sbit	ADC_RD=P0^5;
Sbit	ADC_WR=P0^4;
Sbit	ADC_CLK=P0^3;
Sfr	ADC_DATA=0X90;
Sfr	LCD_DATA=0x90;
Void	LCD_Data (unsigned char);
Void	LCD_Command (unsigned char);
Void	LCD_Init (void);
Void	LCD_Decimal (unsigned char pos,unsigned char var);
Void	LCD_Hex (unsigned char pos,unsigned char var);
Void	LCD_String (unsigned char,unsigned char *var);
Void	LCD_Int16 (unsigned char pos,unsigned int var,unsigned char n);
Void	LCD_Clear ();
Void	Delay (unsigned int tic);
Unsigned char  ADC0804_Read ();
Void	RS232_Init (int  baudrate);
Void	RS232_String (unsigned char *var);
Void	RS232_Send (unsigned char d);

Unsigned RS232_Receive ();
Sbit a= P2^0;
Sbit x= P2^1;
Sbit	c=P2^2;
Sbit	e=P2^3;

Void main (void)

{

Unsigned char Val, d, PORT_2; a=0;

x=0;

c=0;

e=0;

BUZZER=0;

LCD_Init ();

RS232_Init (9600);

LCD_String (0x80,"ADC=");

for (;;)

{

int i=0;

do

{

i++;

                       Delay (50);

Val=ADC0804_Read ();

LCD_Decimal (LINE1+COLUMN5, val);

// LCD_Decimal(LINE1+COLUMN10,y);

d=100; While (d! =0)

{

RS232_Send (val/d+0x30);

Val= val%d;

d=d/10;

}

}

While (i!=5);

RS232_Receive ();

PORT_2=RS232_Receive ();

LCD_String (0xC0,"P2=");

LCD_Decimal (LINE2+COLUMN4,PORT_2);

Switch (PORT_2)

{

case 49: a=~a; x=0;c=0;e=0;Delay(1000);break; case 50:x=~x; a=0;c=0;e=0;Delay(1000);break; case 51:c=~c; a=0;x=0;e=0;Delay(1000);break; case 52:e=~e; a=0;x=0;c=0;Delay(1000);break; case 53:a=0; x=0;c=0;e=0;Delay(1000);break;

}

}

}

Visual basic:

What a GUI??

GUI is stand for Graphical User Interfaces .It allows for interaction with a computer or other media formats which employ graphical images, special graphical element devices and along with text to represent the information and actions available to a user. GUI allow handling any actions like a mouse click, user enter the data and keystrokes. There was a lot of software to develop a GUI. For example, Visual Basic allow a designer to develop GUI application as a monitoring and controlling system , database application for business and education , games software and more applications.

What a Visual Basic??

VISUAL BASIC is a high level programming evolved from the earlier DOS version called BASIC. In Visual Basic programming is done in a graphical environment. In Visual Basic, the GUI also involves in certain action such as interrupts, timers, serial communication, user control and more actions.

Serial Communication in Visual Basic-

Visual Basic can be used to access serial communication function. -Allow hardware part communicate between GUI for several application like monitoring and control process

Communication Control in Visual Basic

Visual Basic allow many additional components to be add in the toolbox. In order to used serial communication, the Microsoft Com components add to toolbox for transmit and receive data from hardware

Visual Basic used in PC-Based Temperature Control

-This project objective is to use PC-Based for monitor and control the temperature. It means that, the GUI developed should have the text or graphic to show current temperature and the fan status information.

-Visual Basic is used to construct A GUI for temperature monitoring and control. As i mention before, A Visual Basic allow a hardware communicate between computer by using serial communication.

-According to this project, the hardware refer to 8051

Microcontroller communicates between a GUI to display temperature value.

Step t hat have been used in building a GUI:

Step 1: Design the interface

Step 2: Set Properties of the controls (Objects)

Step 3: Write the events' procedure

Advantages:

If we compare a simple 8051 based temperature control with PC based temperature control technique then we got that pc based temperature control technique is an more efficient and have an some advantages.

_ Calibration: Calibration is the most important characteristic in any type of instrument. In this project we can easily calibrate by simply language program. We set any desired value and determine if it has any error then we adjust the value or eliminate the error by using programming, no hardware adjusting needed.

_ Graphical Representation: We are used graph for better understanding to solve and minimize the error. Here we plot a curve in between the output value of temperature sensor LM35 and time. 

Disadvantages: 

Generally every instrument has some advantage and disadvantage also. The disadvantages are following:

   Here we used serial port as a connecting wire; if we used USB (universal serial bus) port then we increase the baudrate in between sending and receiving.

   In this system if any problem occurred that means power off or other type of problem faced then the software not work means again start the software. 

Conclusion:

   There are a few test that have be done in completing this project in order to have accurate data and value to be display at PC. There are temperature sensor tests, A/D converter test, RS232 test and complete project test.

   As a conclusion, the project was aim the objective to measured temperatures in several location then display at computer besides, success to develop a GUI by using Visual Basic for temperature monitoring and control.

Future Improvement: In the future, this project can make several improvements in order to add another feature such as using a wireless to communicate between sensor and microcontroller, monitor and control the temperature via internet and using USB for communication between microcontroller and computer. For graphical User Interfaces, add the function to show real time graph between temperature and time. Then add some features to store all data measured as user reference.