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1. MICROCONTROLLER

General description

The P89V51RD2 is an 80C51 microcontroller with 64 kB Flash and 1024 bytes of data

RAM. A key feature of the P89V51RD2 is its X2 mode option. The design engineer can

choose to run the application with the conventional 80C51 clock rate (12 clocks per machine

cycle) or select the X2 mode (6 clocks per machine cycle) to achieve twice the throughput at

the same clock frequency. Another way to benefit from this feature is to keep the same

performance by reducing the clock frequency by half, thus dramatically reducing the EMI.

The Flash program memory supports both parallel programming and in serial In-System

Programming (ISP). Parallel programming mode offers gang-programming at high speed,

reducing programming costs and time to market. ISP allows a device to be reprogrammed inthe end product under software control. The capability to field/update the application

firmware makes a wide range of applications possible.

The P89V51RD2 is also In-Application Programmable (IAP), allowing the Flash program

memory to be reconfigured even while the application is running.

Features

80C51 Central Processing Unit

5 V Operating voltage from 0 to 40 MHz

64 kB of on-chip Flash program memory with ISP (In-System Programming) and IAP

(In-Application Programming)

Supports 12-clock (default) or 6-clock mode selection via software or ISP

SPI (Serial Peripheral Interface) and enhanced UART

PCA (Programmable Counter Array) with PWM and Capture/Compare functions

Four 8-bit I/O ports with three high-current Port 1 pins (16 mA each)

Three 16-bit timers/counters

Programmable Watchdog timer (WDT)

Eight interrupt sources with four priority levels

Second DPTR register

Low EMI mode (ALE inhibit)

TTL- and CMOS-compatible logic levels

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Pin diagram

Figure 1.1 Pin diagram of 8051

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P89V51RD2 pin description

Symbol: P0.0 toP0.7

Pin : 39-32I/O Port 0: Port 0 is an 8-bit open drain bi-directional I/O port. Port 0 pins that have 1s

written to them float, and in this state can be used as high-impedance inputs. Port 0 is also the

multiplexed low-order address and data bus during accesses to external code and data

memory. It uses strong internal pull-ups when transitioning to 1s External pull-ups is

required during program verification or as a general purpose I/O port.

Symbol: P1.0 toP1.7

Pin : 40-44I/O Port 1: Port 1 is an 8-bit bi-directional I/O port with internal pull-ups. The Port 1 pins

are pulled high by the internal pull-ups when 1s are written to them and can be used as

inputs in this state. As inputs, Port 1 pins that are externally pulled LOW will source current(IIL)because of the internal pull-ups. Port 1 also receives the low-order address bytes during

the external host mode programming and verification.

P1.0 I/O T2: External count input to Timer/Counter 2 or Clock-out from Timer/Counter 2

P1.1 I T2EX: Timer/Counter 2 capture/reload trigger and direction control

P1.2 I ECI: External clock input. This signal is the external clock input for the PCA.

P1.3 I/O CEX0: Capture/compare external I/O for PCA Module 0.Each capture/compare

module connects to a Port 1 pin for external I/O. When not used by the PCA, this pin can

handle standard I/O.

P1.4 I/O SS: Slave port select input for SPI

CEX1: Capture/compare external I/O for PCA Module 1

P1.5 I/O MOSI: Master Output Slave Input for SPI


P1.6 I/O MISO: Master Input Slave Output for SPI


P1.7 I/O SCK: Master Output Slave Input for SPI


Symbol: P2.0 toP2.7

PIN : 21-28(I/O with internal pull-up)

Port 2: Port 2 is an 8-bit bi-directional I/O port with internal pull-ups. Port 2 pins are pulled

HIGH by the internal pull-ups when 1s are written to them and can be used as inputs in this

state. As inputs, Port 2 pins that are externally pulled LOW will source current (IIL) because

of the internal pull-ups. It uses strong internal pull-ups when transitioning to 1s. Port 2 also

receives some control signals and a partial of high-order address bits during the external host

mode programming and verification.

Symbol: P3.0 toP3.7

Pin : 11-17(I/O with internal pull-up)

Port 3: Port 3 is an 8-bit bidirectional I/O port with internal pull-ups. Port 3 pins are pulled

HIGH by the internal pull-ups when 1s are written to them and can be used as inputs in this

state. As inputs, Port 3 pins that are externally pulled LOW will source current (IIL)because

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of the internal pull-ups. Port 3 also receives some control signals and a partial of high-order

address bits during the external host mode programming and verification.

P3.0 RXD: serial input port

P3.1TXD: serial output portP3.2 INT0: external interrupt 0 input

P3.3 INT1: external interrupt 1 input

P3.4 T0: external count input to Timer/Counter 0

P3.5 T1: external count input to Timer/Counter 1

P3.6 WR : external data memory write strobe

P3.7 RD : external data memory read strobe

PSEN29 I/O Program Store Enable: PSEN is the read strobe for external program memory.

When the device is executing from internal program memory, PSEN is in active(HIGH).

When the device is executing code from external program memory, PSEN is activated twice

each machine cycle, except that two PSEN activations are skipped during each access toexternal data memory. A forced HIGH-to-LOW input transition on the PSEN pin while the

RST input is continually held HIGH for more than 10 machine cycles will cause the device to

enter external host mode programming.

RST 9 I Reset: While the oscillator is running, a HIGH logic state on this pin for two

machine cycles will reset the device. If the PSEN pin is driven by a HIGH-to-LOW input

transition while the RST input pin is held HIGH, the device will enter the external host mode;

otherwise the device will enter the normal operation mode

EA31 I External Access Enable: EA must be connected to VSS in order to enable the device

to fetch code from the external program memory. EA must be strapped to VDD for internalprogram execution. However, Security lock level 4 will disable EA, and program execution is

only possible from internal program memory. The EA pin can tolerate a high voltage of 12

V.

ALE/PROG30 I/O Address Latch Enable: ALE is the output signal for latching the low

byte of the address during an access to external memory. This pin is also the programming

pulse input (PROG) for flash programming. Normally the ALE is emitted at a constant rate of

1/6 the crystal Frequency and can be used for external timing and clocking. One ALE pulse is

skipped during each access to external data memory. However, if AO is set to 1, ALE is

disabled.

XTAL1 19 I Crystal 1: Input to the inverting oscillator amplifier and input to the internal

clock generator circuits.

XTAL2 18 O Crystal 2: Output from the inverting oscillator amplifier.

VDD 40 I Power supply

VSS20 I Ground

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2. KEIL

Keil software is used to write the microcontroller code and to simulate it on the computer

itself. It is also used to generate the hex code for the code written in ALP or C.

User Vs machine (microcontroller): as the microcontroller know only about the digital value

(i.e. either logic zero or one), so we need to convert the written code in the sets of zero n one.

The KEIL environment provide us the facility to convert the code written in C or ALP to sets

of zero n one (i.e. called hex code).

How to use the keil

Create a new project

To create a new project go to project option then click the new project option. It will ask

to save the project in the desired folder. All the project is saved in the Uv2 format with the

extension of Uv2.

Selecting the device

After saving the project the window will appear which will ask for selecting the device, then

select the company PHILIPS or NXP and then select the device number P89V51RD2.

Figure 2.1 selecting device

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After selection of device, one more window will appear to copy the start up code .After

clicking ok option the project format is ready to simulate the code.

Writing Code

clickthe new file in the FILE menu. Then a new file will appear in which code must bewritten in any programming language like C or ALP. The window will appear as shown

below

Figure 2.2 writing code in editor window

Saving the code

Code written in C should be saved with the extension .c (i.e. the file is stored as

filename.c). The code written in ALP(assembly language programming) has to save with the

extension of .a.

Adding the code file in the project

Right click on source group 1 ,the option Add files to group source group1 will appear.

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Figure 2.3 Adding files to group

Simulating code and checking

Click the debug option and click start/stop debug session then the the window will appear

as follows:

Figure 2.4 Starting debug session

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The keil we use having limitation to simulate the maximum code size 2KB.this window is

just for a warning message, so, just press ok for that option. After that the project is ready to

run.

The microcontroller is having 4 ports. Each port is having 8 pins. Each port can be used

either as input or output port. By using KEIL integrated development environment, we can

check all the input and output on computer itself.

For that when your project is ready to run then click the option peripheral then go to I/O

ports and then select the ports which all are required.

Figure 2.5 Testing of code

Testing of code

Code can be tested on computer itself. After selecting the port, just press run on the

window and give the input to the port and the corresponding output will automatically appear

on other port.

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Figure 2.6 Simulation

Compilation

Compilation can be done by clicking translate current file and then building by clicking built

target.It will generate the hex code .But before that settings must be changed, for that project option

selected and then Options for Target target 1must be clicked.

Figure 2.7 To select target

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A new window will appear as sho

Here,the frequency of crystal whiROM(0x0-0xFFFF)option must

option Create HEX Filemust be

automatically.

wn below, here we need to change the Xtal

Figure 2.8 To set Xtal(MHZ)

ch we are going to use must be filled. For thae clicked. Then the option output must be

selected. Then build target will generate the

(MHz):

t Use On-chipclicked and the

HEX code

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3. ISIS PROTEUS

ISIS incorporates a number of features which aid in the management of large designs. It is

used to produce designs containing many thousands of components.

ISIS provides the means to enter the design in the first place, the architecture for real time

interactive simulation and a system for managing the source and object code associated with

each project. In addition, a number of graph objects can be placed on the schematic to enable

conventional time, frequency and swept variable simulation to be performed.

FEATURES

The simulator runs on Windows 98/Me/2k/XP and later. It allows automatic wire routing and

dot placement/removal. It contains powerful tools for selecting objects and assigning their

properties. It ensures full support for buses including component pins, inter-sheet terminals,

module ports and wires. It includes bill of materials and electrical rules check reports. Net list

outputs to suit all popular PCB layout tools.

ISIS AND NETWORKS

ISIS is fully network compatible. The library files can be set to Read Only. This prevents

users from messing with symbols or devices that may be used by others. Since the registry

determines the location of library files, it follows that users can have individual

USERDVC.LIB files in their personal or group directories.

DESCRIPTIONS

ISIS program must be started.The start button must be clicked. Along the top of the screen isthe menu bar. The largest area of the screen is called the editing window, and it acts as a

window on the drawing - this is where the wire-up components can be placed. The smaller

area at the top right of the screen is called the overview window. In normal use the overview

window displays an overview of the entire drawing - the blue box shows the edge of the

current sheet and the green box shows the area of the sheet currently displayed in the editing

window. However, when a new object is selected from the object selector the overview

window is used to preview the selected object.

The area of the drawing is displayed in the editing window to simply 'pan' the editing window

up, down, left or right, position of the mouse pointer over the desired part of the editing

window and the F5 key is pressed. The SHIFT key is pressed and the mouse is bumpedagainst the edges of the editing window to pan up, down, left or right.F8 key is pressed to

display the whole drawing. The SHIFT key is pressed down and dragged out a box around

the area to zoom in to .Zoom In, Zoom Out, Zoom Full or Zoom Area icons on the toolbar

also can be used for zooming. Below the Overview Window is the Object Selector which is

used to select devices, symbols and other library objects.

STEPS TO DRAW THE DESIGN

The p button at the top left corner of the object selector is selected. Clicking left causes the

device selector dialogue box to appear and select the various devices from the libraries.Theobjects selector displays all the parts in the currently selected library according to the settings

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in the extensions selector. Click left once on a part to browse or double-click a part to pick

it in to the design. The browser displays the last selected part in the parts selector as a means

of browsing the contents of the library. Whenever a device is selected in the device selector,

the selected device is previewed in the overview window.

By clicking left or right on the Rotation and/or Mirror icons, the device is redrawn topreview the new orientation. The preview remains until the device is placed or until another

command or action is performed. It should be ensured that the device is selected and the

mouse pointer is moved into the middle of the editing window. The left mouse button must

be pressed down. An outline of the device will appear which can be moved around by

dragging the mouse. When the button is released, the component will be placed and is drawn

in full. The rotation of the last object tagged can be adjusted in this way; the mirror icon can

similarly be used to reflect the last object tagged. ISIS senses a component pin and deduces

that a wire is needed to connect from it. To signify this, it displays a green line which goes

from the pin to the pointer. Manually a wire can be routed by simply clicking left on the first

pin, clicking left at each point along the required route and then finished by clicking left on

the second pin. To complete this section of the drawing, place the two generic and oneground terminals and wired. To do this, the terminal icon is selected. The object selector

changes to a list of the terminal types available. The ground terminal is selected and placed it.

Work must be saved at any time by means of the Save command on the File menu. Save as

option also allows saving it with a different filename to run the program, the play button must

be clicked and to terminate the program, the stop button is clicked.

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4. FLASHMAGIC

Flash Magic is a PC tool for programming flash based microcontrollers from NXP using a

serial or Ethernet protocol while in the target hardware. There are five simple steps to erase

and programme a device and setting key options. It programs Intel Hex Files. There is

Automatic verifying option after programming.

MAIN WINDOW

After flashmagic software start-up, the main window will be as shown below:

Figure 4.1 Main window

Communication

For this select device by selecting select and select P89v51RD2device

Then specify COM1 in COMPORT row.

Specify the baud rate as 9600 Fill interface row as NONE(ISP).

Specify operator frequency as 12MHz.

Erase

Enable the Erase block used by HEX file, as shown below:

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Figure 4.2 Erasing blocks used by Hex file

Hex File selection

Select the required/generated hex file by pressing Browse button, as shown below:

Figure 4.3 Choosing Hex file

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Then select hex file and its path specified in the Hex File.

Options

Go to options menu from that select Advanced option and in that press Hardware

Config

Here, Enable the use DTR to control RST which is normally disabled as shown below:

Figure 4.4 Hardware configure

Then press ok

Press the start button from main window as shown below:

Figure 4.6 Start dumping into specified IC

So by pressing start button the hex file will be start dumping into the specified

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5. UNIVERSAL PROGRAMMER-TOPWIN6

The TOP3100 programmer has compact size, lower power consumption, and high reliability.

This is an universal equipment especially designed for MCU and EPROMs programming.USB universal serial port is used to connect with the PC, communications, support

2000/xp//Vista/Win7, software upgrades and flexible.

Features

Full driving with 48 pin(Vpp/Vcc/GND/TTL), good for future upgrading.

Support 2.5V to 6.5V device.

Selectable to use USB or external 5V power supplier to supply power.

Transmission speed is 12MHz/s.

Suitable to work with Desktop and Laptop. With current protection function, effectively protects the programmer and devices.

Automatic Pin status detection.

48 pins self-lock sockets.

Support operation system: WINDOWS7/vista/2000/2003/XP;

Plastic cabinet, small size and light weight.

Auto detects company and type of the IC.

Software support: TopWin ver6.0 or newer.

Specifications

Software: Topwin6 (forWindows7/Vista/2003/2000//xp)

Actual tested Speed(PIII/800M, Windows98se,USB1.1):28F320 write and check 104seconds,29LF320 write and check 112 seconds, p89c58 write and check 5 seconds.

Size: 155mm*110mm*26mm

Weight for the programmer only : 275g

Power: < 2.5W (5V/500mA)

48 Pin self-lock socket (Changeable)

This auction includes

New Top3100 USB Universal programmer; Software: TopWin6 (for Windows7/Vista/xp);

USB cable.

Main window:

After TopWin start-up, Main window of topwin6 will be showed on the screen as follows:

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Figure 5.1 Main window

Select device by multiple list

Choose "Run" ,and from that select select chip then appeared the dialog box as follows:

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Figure 5.2 Select chip

Select device

Select "Type of Device" in the "Type" menusuch as "MPU".

Select a manufacturer from the list of "Manufacturer", like "PHILIPS".

Select a device type from the list of "Device", like select"P89V51RD2".Then dialog box appears as follows:

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Figure 5.3 Select P89v51RD2

Erasing previous content:

To erase the previous content from buffer, go to Run menu and from that selectErase, as shown in the dialog box:

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Figure 5.4 Erase before loading

Now after erasing it is ready to load the new data.

After being erased the device shows "FF".

Loading file to buffer

Window under the buffer will show "data from xxxx to xxxx".The function is helping you to

write in the correct address.

Loading step is the same with "Open file".

Select the empty device before setup.

To load the new data go to File menu and select Load Data option, as shown in the

below dialog box:

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Figure 5.5 Select load data

Then select the required/generated hex file with filename.hex extension from the library

and open it, as shown below:

Figure 5.6 Choosing the Hex file

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1Choose the file format in "project file", for example a hexadecimal file, .HEX

2. Choose byte. Many devices should set byte while shown the dialog.

3Select the way to fill, if it is 00, then the buffer zone so if it is FF, so is the blank or No

clear fill mode.

4Select the address of buffer zone. Normally starting address will be o.

Figure 5.7 Select the address of buffer zone

Operation

Operation box on the left hand beside buffer will spring the five functions of the device.

Select the function which is needed, then press[Go], programmer will operate "Erase""Blank" "Write code" "Verify" "Config Secure are the operation done by pressing

start and GO buttons as shown below:

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Figure 5.8 Select start and go

The verify menu is selected by choosing secure from Run and is chiefly used to

test the common static storage SRAM. Press "Start"[Go], and the programmer test eachbyte of memory to ensure the test is performed stably, as shown below.

Figure 5.9 To verify

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Ex. No : 1

Date :

ARITHMETIC OPERATIONS USING 8051

AIM:To design and implement arithmetic operations by interfacing KEYPAD and LCD using 8051

microcontroller.

HARDWARE REQUIRED:

1. VSM DLL model keypad.2. 16X2 Line LCD (LM016L).

3. PHILIPS P89C51RD2XX.

4. TOP2048 Programmer kit.5. Power supply(5v).

6. Connecting wires.

SOFTWARE REQUIRED:1. Keil uvision 3.

2. ISIS Proteus Professional 7.

3. Topwin VER5.49.

ALGORITHM:

1. Initialize the ports using cct_init() function.

2. Initialize the Port1 for input interfacing with keypad.(Rows are assigned toP1.0,P1.1,P1.2,P1.3& columns are assigned to P1.4,P1.5,P1.6&P1.7)

3. Initialize the Port2 for data pins of LCD.

4. Initialize the P3.6 for enable and P3.7 for RS of LCD.

5. Get the key value and store it in num1 using get_key() function.

6. Check the num1 with all cases in get_num() if not display wrong input using DispError()

function.

7. Display the num1 on LCD using writedata().

8. Get the operator using get_func();

9. Check the operator with all cases in get_func() if not display wrong input using DispError()

function.

10. Similarly for num2.

11. Press= key and perform the operation .

12. Check whether num less than zero then perform the operation and display the number with

signed value.

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FLOWCHART:

START

Initialize the ports using

cct_init()

Initialize the P1 for input

interfacing with keypad

Initialize the P2 for data pins

of LCD

Initialize the P3.6 for E &

P3.7 for RS of LCD

Get the key value

Store the num1 using get_key()

Check num1

in get_num()

Display wrong input

using disp error()

Display the num1 on LCD usingwrite data()

Get the operator using get_fun()

*

NO

YES

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*

Checkoperator in

get_fun()Display wrong function using

Disp error()

store the num2 using

get_key()

Check

num2 in

get_fun()

Press = key & perform the

operation

Display wrong input using

Disp error()

Display the number with

signed value

Check the

num < 0

YES

NO

NO

NO

YES

YES

Stop

Display the result

Fig 1.2 Arithmetic Operation Using 8051 Microcontroller

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Program:

#include#include

#define Error 13

void cct_init(void);

void delay(int);void lcdinit(void);

void writecmd(int);void writedata(char);

void writeline(char[]);

void ReturnHome(void);char READ_SWITCHES(void);

char get_key(void);

int get_num(char);

char get_func(char);void DispError(int);

void disp_num(int);sbit RowA = P1^0;sbit RowB = P1^1;

sbit RowC = P1^2;

sbit RowD = P1^3;sbit C1 = P1^4;

sbit C2 = P1^5;

sbit C3 = P1^6;

sbit C4 = P1^7;sbit E = P3^6;

sbit RS = P3^7;

int main(void){

char key;

int num1 = 0;char func = '+';

int num2 = 0;

cct_init();

lcdinit();while(1)

{

key = get_key();writecmd(0x01);

writedata(key);

num1 = get_num(key);

if(num1!=Error)

{key = get_key();

writedata(key);

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func = get_func(key);

if(func!='e'){

key = get_key();

writedata(key);

num2 = get_num(key);

if(num2!=Error){

key = get_key();

writedata(key);

if(key == '=')

{

switch(func){

case '+': disp_num(num1+num2); break;case '-': disp_num(num1-num2); break;case 'x': disp_num(num1*num2); break;

case '/': disp_num(num1/num2); break;

}}

else

{

if(key == 'C')writecmd(0x01);

else

DispError(0);}

}

}}

}

}

void cct_init(void)

{P0 = 0x00;

P1 = 0xf0;

P2 = 0x00;P3 = 0x00;

}

void delay(int a)

{

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int i;

for(i=0;i

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void writeline(char Line[]){

int i;

for(i=0;i

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{

char key = 'n';

while(key=='n')

key = READ_SWITCHES();

return key;

}

int get_num(char ch)

{switch(ch)

{

case '0': return 0; break;

case '1': return 1; break;case '2': return 2; break;

case '3': return 3; break;case '4': return 4; break;case '5': return 5; break;


case '7': return 7; break;case '8': return 8; break;


case 'C': writecmd(0x01); return Error; break;

default: DispError(0); return Error; break;}

}

char get_func(char chf)

{

if(chf=='C'){

writecmd(0x01);

return 'e';

}

if( chf!='+' && chf!='-' && chf!='x' && chf!='/' )

{DispError(1);

return 'e';

}

return chf;

}

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void DispError(int numb)

{writecmd(0x01);

switch(numb)

{case 0: writeline("Wrong Input"); break;

case 1: writeline("Wrong Function"); break;default: writeline("Wrong Input"); break;

}

}

void disp_num(int numb)

{

unsigned char UnitDigit = 0;unsigned char TenthDigit = 0;

if(numb

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Circuit diagram:

Output:

VSM DLL model keypad

P89C51RD2

LCD LM016L

Fig. 1.3 8051 Microcontroller interfacing with LCD & Keypad Connection

Fig 1.4 Sample Output for Addition

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Fig 1.5 Sample Output for Subtraction

Fig 1.6 Sample Output for Multiplication

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Hardware Diagram:

Result:Therefore, arithmetic operations by interfacing keypad and lcd using 8051 microcontroller has

been executed successfully.

Fig 1.7 Sample Output for Division

Fig 1.8 Hardware Setup for Arithmetic Operation

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EX NO: 2

DATE:

SERIAL COMMUNICATION WITH UART OF 8051:

AIM

To establish serial communication with UART of 8051 and simulate the output

through Kiel software.

COMPONENTS REQUIRED

Microcontroller IC P89V51RD2FN

Max 232 IC & 9pin RS232 female connector.

Bread board & connecting wires.

Resistors 1K,8.2k,10k-10nos

Crystal Oscillator 11.0592 MHz

Capacitor 1f, 10f, 33pf, 0.1f,150pf-6nos

BLOCK DIAGRAM

Figure 2.1 Block Diagram-Serial Communication

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SERIAL COMMUNICATION

PC/compatible computers (Pentium) microprocessors normally have two COM

ports

Both ports have RS232-type connectors

COM ports are designated as COM 1 and COM 2 (replaced by USB ports)

Serial communication is often used either to control or to receive data from an

embedded microprocessor.

Serial communication is a form of I/O in which the bits of a byte begin transferred

appear one after the other in a timed sequence on a single wire.

Serial communication has become the standard for inter-computer

communication. In this lab, we'll try to build a serial link between 8051 and PCusing RS232 and MAX 232 to make it TTL compatible.

MAX-232

Converts from RS232 voltage levels to TTL voltage levels

Uses a +5 V power source

MAX232 has two sets of line drivers for transferring and receiving data

Line drivers used for TxD are called T1 and T2 Line drivers for RxD are designated as R1 and R2

T1 and R1 are used together for TxD and RxD of the 8051

Second set is left unused

(a) Inside MAX232 b) its Connection to the 8051 (Null Modem)

Figure 2.2 - MAX-232

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RS232 STANDARDS

Most widely used serial I/O interfacing standard

Input and output voltage levels are not TTL compatible

1 bit is represented by -3 to -25 V

0 bit is +3 to +25 V

-3 to +3 is undefined

To connect RS232 to a microcontroller system must use voltage converters such as

MAX232 to convert the TTL logic levels to the RS232 voltage levels, and vice versa

9 PIN RS232 FEMALE CONNECTOR

Data communication classification

DTE (data terminal equipment)

DCE (data communication equipment)

DTE - Terminals and computers that send and receive data

DCE - Communication equipment responsible for transferring the data

Simplest connection between a PC and microcontroller requires a minimum of

three pins, TxD, RxD, and ground

Figure 2.3

PC/compatible computers (Pentium) microprocessors normally have two COM

ports

both ports have RS232-type connectors

COM ports are designated as COM 1 and COM 2 (replaced by USB ports)

can connect the 8051 serial port to the COM 2 port

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9 PIN RS232

Figure 2.4- RS232 DB9 Female Connector

DESCRIPTION

PROGRAMMING 8051 TO TRANSFER DATA SERIALLY:

1) The TMOD register is loaded with the value 20H, indicating the use of timer1 in mode2 toset the baud rate.

2) The TH1 is loaded with one of the baud rate values for serial data transfer.

3) The SCON register is loaded with value 50H, indicating serial mode1,where an 8-bit data

is framed with start and stop bits

4) TR1 is set to 1 to start timer1

5) TI is cleared by the CLR TI instruction

6) The character byte to be transferred serially as written into the SBUF register

7) The TI flag bit is monitored with the use of instruction JNB TI, XX to see if the

character has been transferred completely

8) To transfer the next character, go to step 5.

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CODING

MOV TMOD,#20H ;Timer 1 mode 2(auto reload)

MOV TH1,#-3 ;9600 baud rate

MOV SCON,#50H ;serial mode 1,REN enabled

SETB TR1 ;to start timer 1

MOV A,#"H" ;transfer H to A

ACALL TRANS ;call subroutine

MOV A,#"I" ;transfer I to A


MOV A,#" " ;transfer to A


MOV A,#"H" ;transfer H to A


MOV A,#"O" ;transfer O to A


MOV A,#"W" ;transfer W to A




MOV A,#"A" ;transfer A to A


MOV A,#"R" ;transfer R to A


MOV A,#"E" ;transfer E to A




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MOV A,#"Y" ;transfer Y to A


MOV A,#"O" ;transfer O to A


MOV A,#"U" ;transfer U to A


MOV A, #"?" ;transfer ? to A


AGAIN:SJMP AGAIN ;be in this loop always

TRANS: MOV SBUF,A ;transfer contents of A serially

HERE: JNB TI,HERE ; wait for transmission to be over

CLR TI ;clear TI for next transmission

RET ;go back to next instruction

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CIRCUIT DIAGRAM

Figure 2.5 Circuit Diagram

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FLOW CHART

Figure 2.6 Flow Chart

Start

Start the timer TR1

Transfer data to SBUF register

Check TI

flag

Set TMOD for

mode selection

Set TH1 to set

baud rate

Load the value to

SCON register

Send next data to be transmitted

Transfer current data

Stop

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SIMULATION OUTPUT

Figure 2.7 Simulation Output

HYPER-TERMINAL OUTPUT

Figure 2.8 Hyper terminal Output

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HARDWARE SETUP

Figure 2.9 Hardware Setup

RESULT

Thus the Serial Transmission of data from Microcontroller to HyperTerminal was set

by using RS 232 Cable

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EXNO:3

DATE:

TRAFFIC CONTROL IMPLEMENTATION USING 8051 MICROCONTROLLER

AIM

To implement traffic control using 8051 microcontroller interfacing seven segment display.

COMPONENTS REQUIRED:

Microcontroller (P89V51RD2)

Seven segment display (anode)- 2

Development board

Universal programmer

connecting wires

ALGORITHM

Include the header file using the comment #include

Define RED led, YELLOW led, GREEN led,RED1 led,YELLOW1 led,GREEN1 led

for the port P1 ,pin 0,pin 1,pin 2,pin 5,pin 6,pin 7 respectively

Declare function call display1(), display(),delay()

In the main program give input to RED led (port1^0) and GREEN1 led(port1^7) and

other all led is off

Call the display function to decrement the counter from 9 to 0

>declare the 7 segment code in array.The code is written for common anode.

>call the delay function to execute the delay by the timer between the decrement

TMOD=0x01 set timer 1 and mode 1 of 8 bit microcontroller

TH0=0xa0 load the timer higher 8 bit with the value a0

TL0=0x30 load the timer lower 8 bit with the value 30

TR0=1 turn on T0

while(TF0==0) wait for TF0 to roll over

TR0=0 turn OFF T0

TF0=0 clear TF0

Display function executed the program returns to the main program,

Give input to YELLOW led(port P1^1) call for msdelay for 10 secs. and

simultaneously RED1 led (port P1^5) is ON.

YELLOW led goes low. GREEN led (port P1^2) is ON .Now Display1 function is

called for display the counter value from 9-0

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Display1 function has different time delay from display function since YELLOW

led goes from low to high.

The loop continues to ON the led in the sequence RED -GREEN1-YELLOW-

RED1-GREEN-YELLOW1-GREEN1-RED with the counter decrement from 9 to 0.

FLOW CHART

Fig 3.1 Flowchart of Traffic Control Implementation using 8051 Microcontroller

INITIALIZE DISPLAY,DISPLAY1,

DELAY, MSDELAY FUNCTION

SET PORT PIN FOR

RED,RED1,YELLOW,

YELLOW1,GREEN,GREEN1 LED

COUNTER DECREMENT

FUNCTION

DELAY

FUNCTION

GIVE INPUT TO RED ,GREEN1 LED &

CALL DISPLAY FUNCTION

START

YELLOW LED =1 & CALLS MSDELAY

FUNCTION

GREEN =1 & RED1=1 & CALL DISPLAY1

FUNCTIONCOUNTER DECREMENT

FUNCTION

DELAY

FUNCTION

WHILE(1)

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CIRCUIT DIAGRAM

Fig 3.2 Circuit Diagram of Traffic Control Implementation Using 8051 Microcontroller

Seven segment

display

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CODING

#include

sbit rlight=P1^0;

sbit ylight=P1^1;

sbit glight=P1^2;sbit r1light=P1^5;

sbit y1light=P1^6;

sbit g1light=P1^7;

void display1();

void display();

void delay();

void msdelay(unsigned int);

void main()

{

unsigned char i;

while(1){

ylight=0;

r1light=0;

y1light=0;

glight=0;

rlight=1;

g1light=1;

display();

rlight=0;

glight=0;

g1light=0;

r1light=1;

display1();

r1light=0;

glight=0;

ylight=0;

rlight=1;

y1light=1;

for(i=0;i

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} } }

void display1()

code unsigned char pattern[10 ]={0x98,0x80,0Xf8,0X02,0X12,

0X99,0Xb0,0Xa4,0Xf9,0Xc0};

unsigned int n,i;

ylight=1;for(i=0;i

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ISIS STIMULATION OUTPUT

Fig 3.3 ISIS Stimulation of Traffic Control Implementation with 8051 Microcontroller

HARDWARE OUTPUT

Fig3.4 Hardware Output of Traffic Control Implementation with 8051 Microcontroller

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RESULT

Traffic control using 8051 microcontroller with seven segment display is implemented and

output is verified.

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EX NO: 4

DATE:

COUNTER PROGRAMMING WITH TIMERS IN 8051

MICROCONTROLLER

AIM

To establish and develop an counter application for P89v51RD2FN microcontroller, by

programming in keil with timers using delay.

COMPONENTS REQUIRED

Microcontroller (P89V51RD2)

Led-4(Yellow)

Development board Universal programmer

Connecting wires

ALGORITHM

Include the header file and declare the delay function.

Assign the characters x and i

Initialize the port 1 as output by assigning port 1=x.

Initialize for loop with x=0 and the count increment for x

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FLOWCHART

No

Yes

No

Yes

Figure 4.1 Upcounter Implementation Using 8051 Microcontroller

Initialize Unsigned character(x=0,i=0)

Assign (P1=x)

If

i

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CIRCUIT DIAGRAM

Figure 4.2 Circuit Diagram for Upcounter Implementetion

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CODING

#include

void T1M1delay(void);

void main()

{

unsigned char x,i;

while(1)

{

for(x=0;x

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0-OFF

1-ON

Table 4.1 Truth Table of Upcounter Implementation

RESULT

Thus the upcounter application with timer using delay was successfully executed and

verified.

UPCOUNT

LED 4 LED 3 LED 2 LED 1

0 0 0 0

0 0 0 1

0 0 1 0

0 0 1 1

0 1 0 0

0 1 0 1

0 1 1 0

0 1 1 1

1 0 0 0

1 0 0 1

1 0 1 0

1 0 1 1

1 1 0 0

1 1 0 1

1 1 1 0

1 1 1 1

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ISIS SIMULATION OUTPUT

Figure 4.3 ISIS Stimulation of Upcounter Implementation Using 8051 Microcontroller

HARDWARE OUTPUT

Figure 4.4 Hardware Output of Upcounter Implementation Using 8051 Microcontroller

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4.1 KEYPAD INTERFACING USING 8051 MICROCONTROLLER

CIRCUIT DIAGRAM

Figure 4.1.1 Circuit Diagram of Keypad Interfacing

CODING

#include

sbit led0=P1^0;

sbit led1=P1^1;

sbit led2=P1^2;

sbit led3=P1^3;

sbit led4=P1^4;

sbit led5=P1^5;

sbit led6=P1^6;

sbit led7=P1^7;

sbit col1=P3^0;

sbit col2=P3^1;

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sbit col3=P3^2;

sbit row1=P2^0;

sbit row2=P2^1;

sbit row3=P2^2;

void delay(unsigned int msec) //Time delay function

{

int i,j ;

for(i=0;i

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delay(100);

led1=1;

delay(100);

led2=1;

delay(100);

led0=led1=led2=0;

delay(100);

break;

case 4:

led0=1;

delay(100);

led1=1;

delay(100);

led2=1;

delay(100);

led3=1;

delay(100);

led0=led1=led2=led3=0;

delay(100);

break;

case 5:

led0=1;

delay(100);

led1=1;

delay(100);

led2=1;

delay(100);

led3=1;

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delay(100);

led4=1;

delay(100);

led0=led1=led2=led3=led4=0;

break;

case 6:

led0=1;

delay(100);

led1=1;

delay(100);

led2=1;

delay(100);

led3=1;

delay(100);

led4=1;

delay(100);

led5=1;

delay(100);

led0=led1=led2=led3=led4=led5=0;

break;

case 7:led0=1;

delay(100);

led1=1;

delay(100);

led2=1;

delay(100);

led3=1;

delay(100);

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led4=1;

delay(100);

led5=1;

delay(100);

led6=1;

delay(100);

led0=led1=led2=led3=led4=led5=led6=0;

break;

case 8:

led0=1;

delay(100);

led1=1;

delay(100);

led2=1;

delay(100);

led3=1;

delay(100);

led4=1;

delay(100);

led5=1;

delay(100);

led6=1;

delay(100);

led7=1;

delay(100);

led0=led1=led2=led3=led4=led5=led6=led7=0;

break;

}

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}

void check_col1() //Function for checking column one

{

row1=row2=row3=1;

row1=0;

if(col1==0)

display(1);

row1=1;

row2=0;

if(col1==0)

display(2);

row2=1;

row3=0;

if(col1==0)

display(3);

}

void check_col2() //Function for checking column two

{

row1=row2=row3=1;

row1=0;

if(col2==0)

display(4);

row1=1;

row2=0;

if(col2==0)

display(5);

row2=1;

row3=0;

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if(col2==0)

display(6);

}

void check_col3() //Function for checking column three

{

row1=row2=row3=1;

row1=0;

if(col3==0)

display(7);

row1=1;

row2=0;

if(col3==0)

display(8);

}

void main()

{

P1=0x00;

col1=col2=col3=1; //Input Port

while(1)

{

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if(col1==0)

check_col1();

else

if(col2==0)

check_col2();

else

if(col3==0)

check_col3();

}

}


Figure 4.1.2 ISIS Simulation of Keypad Interfacing With LED

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EX:NO: 5

DATE:

DISPLAYING THE POSITION OF KEY PRESSED USING 7 SEGMENT

DISPLAY

AIM

To display the position of the key pressed using 7 segment display in the

microcontroller

COMPONENTS REQUIRED

Microcontroller P89V51RD2-1

Development board

Bread board


connecting wires

Keypad-1

BCD to 7 segment Decoder, IC 7447-2

7 Segment display(common anode type)-2

AND 74LS21-1

ALGORITHM

Initializing port 2 as output port and port 1 as input port by giving P1=0x0F

External interrupt pin is enabled.

When the interrupt occurred is detected by pressing the key, external interrupt

is disabled, in order to avoid any interrupt until the key press is detected

Flag is also set (flag=0xff) to indicate that there is an external interrupt

Now scanning of keypad starts to detect the position of key pressed

Initially scancode value is given as 0xef and this value is assigned to port1 and

keycode

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The following two conditions are checked if scancode value is not equal to

0xff;

a) ((keycode&0x0f)!=0x0f); if this condition is true, no change in the

keycode value and detects the column value

b) else the following operation is done

scancode=(keycode

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FLOWCHART

NO

YES

YES

NO

NO

YES

START

Initialize

IE=0; EX1=1; EA=1

If key

press

Flag=0xff

INT1

=1

EX1=0,Scancode=0XEF

If

scancode!=

0xXFF

P1=Scancode

Keycode=p1

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YES

NO

NO

YES

NO

YES

Figure 5.1: Flowchart to scan the position of key pressed by making keypad as external

interrupt

(keycode&0x0f)

!=0x0f

scancode=(keycode>1)|0x0f

Keycode=~keycode

P2=keycode

P1=0x0F

INT1==1

Flag=~flag

Flag==0

EXT=1

END

C

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CIRCUIT DIAGRAM

Figure 5.2: Circuit diagram

displays

to display the position of key pressed using 7 segment

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CODING

#include

#include

#define byte unsigned char

//Interrupt service routine

Void keyinterrupt() interrupt 2

{

int t;

byte keycode, scancode, flag=0xff;

t=5000;

while(t--);

if(INT1==1)

return;

EX1=0;

scancode=0xef;

while (scancode!=0xff)

{

P1=scancode;

Keycode=P1;

if((keycode&0x0f)!=0x0f)

break;

scancode=(keycode

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P1=0X0F;

while(1)

{

if(INT1==1)

{

flag=~flag;

if(flag==0)

break;

}

t=10000;

while(t--);

}

EX1=1;

return;

}

Void main(void)

{

IE=0;

EX1=1;

EA=1;

P2=0XFF;

P1=0X0F;

while(1)

{

}}

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ISIS SIMULATON OUTPUT

Figure 5.3: ISIS simulation output for displaying the position of key pressed using the

seven segment display

RESULT

Thus, keypad is used as the external interrupt and the position of the key pressed is

displayed using two 7 segment display and verified

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EX.NO: 6

DATE:

CONTROL FOUR LED USING SWITCH IN 8051 MICROCONTROLLER

AIM

To control four LED in different sequence using switch in microcontroller P89V51RD2.

COMPONENTS REQUIRED

Microcontroller P89V51RD2


LED-4

Switch-1

Connecting wires

ALGORITHM

Initialize port1 as output port by assigning 0 to port1

Initialize pin3.4(T0-timer0 input) of port3 as input port by assigning 1 to pin3.4

TMOD(Timer/counter mode control register) is an 8-bit register, both timers 0 and 1 use

the same register to set various timer operation mode.

Set TMOD with value 0x16.

Timer0 is used as counter with mode2 8-bit auto-reload.Mode2 is an 8-bit timer it allows

only values of 00 to FFH to be loaded into the timers register TH0.After TH0 is loaded

with the 8-bit value the 8051 gives a copy of it to TL0.

Set values in Timer0 (16-bit register) as (timer0 low byte register )TL0=0x0FB and(

high byte register)TH0=0x0FB and set TR0=1(Timer0 run control bit) to start the counter

Within infinite while loop different sequence for each input count(TL0) is defined using

switch case. Each value in each sequence is assigned to output port1 with a delay of 2

seconds.

Timer1 is used as timer with mode1 (16-bit timer) for generating delay. Initiate for loop

with i=0.

Set values in Timer1(16-bit register) as TL1=0x0A5 and TH1=0x0FE.start Timer1 by

setting TR1=1(Timer1 run control bit is ON) and continuously monitor timer1 overflow

flag (TF1).If TF1==1 then, clear by setting TF1=0 and TR1=0(Timer1 run control bit is

OFF)and, increment i in for loop.

Repeat the aboveuntil i

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FLOWCHART

Figure 6.1 flowchart for controlling four LED using switch in microcontroller

Start

Initialize port1 as output P1=0x0000;

Initialize pin3.4 (T0) as input T0=1;

Initialize TMOD=0x016, TL0=0xFB, TH0=0xFB and, set

TR0=1to start counter

Interrupt using switch connected to T0

if(TL0==0Xfc)

if(TL0==0Xfd)

if(TL0==0Xff)

if(TL0==0Xfe)

P1=0x01;delay();

P1=0x03;delay();

P1=0x05;delay()

P1=0x09; delay();

P1=0x02;delay();

P1=0x03;delay();

P1=0x06;delay();

P1=0x0A; delay();

P1=0x04;delay();

P1=0x05;delay();

P1=0x06;delay();P1=0x

0C; delay();

P1=0x08;delay();P1=0x09;delay();

P1=0x0A;delay();

P1=0x0C;delay();

Yes

NO

Yes

NO

Yes

NO

YesNO

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Figure 6.2 Flowchart for delay

Set TL1=0x0A5 and

TH1=0x0FE

Set TR1=1

while(TF1==0);

Yes

TR1=0; TF1=0;

increment i;

i=0

i

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CIRCUIT DIAGRAM

Figure 6.3 Circuit diagram to control four LED using switch in microcontroller

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CODING

#include

void delay();

void main(void)

{P1=0X00;

T0=1;

TMOD=0x16;

TL0=0xFB;

TH0=0xFB;

TR0=1;

while(1)

{

switch(TL0)

{

case 0xfc:P1=0x01;

delay();

P1=0x03;

delay();

P1=0x05;

delay();

P1=0x09;

delay();

break;

case 0xfd:

P1=0x02;delay();

P1=0x03;

delay();

P1=0x06;

delay();

P1=0x0A;

delay();

break;

case 0xfe:

P1=0x04;

delay();

P1=0x05;

delay();

P1=0x06;

delay();

P1=0x0C;

delay();

break;

case 0xff:

P1=0x08;

delay();P1=0x09;

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delay();

P1=0x0A;

delay();

P1=0x0C;

delay();

break;}

}

}

void delay()

{

inti;

for(i=0;i

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SAMPLE OUTPUT

Figure 6.4 ISIS simulation output control four led using switch in 8051 microcontroller

HARDWARE OUTPUT

Figure 6.5 Hardware Implementation of Control four led using Switch in 8051

Microcontroller

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SAMPLE OUTPUT

TL0=0XFC TL0=0XFD

TL0=0XFE TL0=0XFF

RESULT

Thus four LEDs in different sequence using switch in microcontroller P89V51RD2 was

implemented and verified.

LED

1 2 3 4

1 0 0 0

1 1 0 0

1 0 1 0

1 0 0 1

LED

1 2 3 4

0 1 0 0

1 1 0 0

0 1 1 0

0 1 0 1

LED

1 2 3 4

0 0 0 1

1 0 0 1

0 1 0 1

0 0 1 1

LED

1 2 3 4

0 0 1 0

1 0 1 0

0 1 1 0

0 0 1 1

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EXNO:7

DATE:

INTERFACING STEPPER MOTOR WITH 8051

AIM

To write a Program to Interface a stepper motor with 8051c and to rotate in clockwise and

anti-clockwise direction using keil software.

HARDWARE REQUIRED

Microcontroller IC P89C51RD2XXPHILIPS1No

Crystal Oscillator 11.0592 MHz

Capacitor 1f, 10f, 33pf, 0.1f,150pf-6nos

Bread board & connecting wires. Resistors 1K,8.2k,10k,4.7k-10nos

Micro Switch1 Pin

ULN2003-1 No

Stepper motor

SOFTWARE REQUIRED

Keil vision 3

ISIS Proteus Professional 7 Topwin VER5.49

ALGORITHM

Define the delay function.

Initialize the switch, SW.

Making the condition as an infinite loop.

If SW = 0, motor get rotates step by step in a clockwise direction with a delay of 100 ms.

If SW = 1, motor get rotates step by step in a counter-clockwise direction with a delay of

100 ms. This process gets repeated until the power off.

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FLOWCHART

Yes No

Figure 7.1 Flow Chart

Start

Define delay function (MSDelay)

Set port pin for switch (SW)

Initialize switch, SW=1

While(1)

If

SW==0

Assign

P1=0x06

Assign

P1=0x33

Assign

=

Assign

P1=0xcc

Assign

=

MSDelay(100)

Assign

P1=0xcc

Assign

P1=0x99

Assign

P1=0x33

MSDelay(100)

MSDelay(100)MSDelay(100)

MSDelay(100) MSDelay(100)

MSDelay(100) MSDelay(100)

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CIRCUIT DIAGRAM

Fig 7.7:STEPPER MOTOR INTERFACE

Figure 7.2 Circuit Diagram of Stepper Motor Interface

PROCEDURE

1. Write the stepper motor coding for (clock wise rotation) in keil software and generate a

hex code.

2. Dump the hex code in the controller chip using flash magic software.

3. Give the circuit connections as given above.

4. Interface the 8051 controller, ULN2003 and the stepper motor.5. Switch on the power supply and view the clock-wise rotation of stepper motor.

6. Repeat the steps 1-5 for anti-clock-wise rotation of the motor.

To

ULN2003

5V

4.7K

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STEP SEQUENCES

Normal 4-Step Sequence (90 )

CLOCK

WISE

Step # Winding A Winding B Winding

C

Winding

D

Counter

Clockwise

1 1 0 0 1

2 1 1 0 0

3 0 1 1 0

4 0 0 1 1

Table 7.1 4-Step Sequence

STEP ANGLE

Step angle Steps per revolution

0.72 500

1.8 200

2.0 180

2.5 144

5.0 72

7.5 48

15 24

Table 7.2 Step Angle

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CODING

#include

void MSDelay(unsigned int value);

sbit SW=P2^7;

void main(){

SW=1;

while(1)

{

if(SW==0)

{

P1=0x06;

MSDelay(100);

P1=0x0c;

MSDelay(100);

P1=0x09;MSDelay(100);

P1=0x03;

MSDelay(100);

}

else

{

P1=0x06;

MSDelay(100);

P1=0x03;

MSDelay(100);

P1=0x09;MSDelay(100);

P1=0x0c;

MSDelay(100);

}

}

}

void MSDelay(unsigned int value)

{

unsigned int x,y;

for(x=0;x

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Figure 7.3 Simulation of Stepper Motor Interfacing

HARDWARE SNAP SHOT

Figure 7.4 Interfacing Stepper Motor

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RESULT

Thus the program is written to interface stepper motor with 8051c was verified and

executed.

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Ex No:8

Date:

INTERFACING ADC0804 WITH TEMPERATURE SENSOR

AIM

To design and verify the ADC 0804 conversion of data given, using Philips AT89C5

Microcontroller with temperature sensing as a parameter.

COMPONENTS REQUIRED

Philips AT89C51RD2XX Microcontroller

ADC 0804

LM 35 Temperature sensor

Resistor - 10 K ohm

Capacitor- 150 Pico farad

LCD Display

Kiel Simulator

ISIS Emulator

BLOCK DIAGRAM

Figure 8.1 Block Diagram of the Experiment

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CIRCUIT DIAGRAM

Figure 8.2 Circuit Diagram

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ALGORITHM

1. START

2. Select the specific ports of microcontroller.

3. Initialize the interrupts.

4. Move the 8-bit data into ACC and store the data from accumulator into any register

5. Write the commands of LCD display for output data.

6. Move again data from register to accumulator for division operation.

7. Convert the data from ASCII values.

8. Display the data through ADC output pins.

9. Generate delay where ever necessary.

10. STOP

ALGORITHM BETWEEN THE DATA FROM LM35 AND ADC0804

1. START

2. Temperature sensors LM35 sense the output temperature.

3. Initialize the CS=0 pin and low to high transition, to enable the data to be write to

ADC, which starts the conversion.

4. Keep the INTR pin always low to ensure that process of conversion is finished.

5. Initialize the CS=1 pin and pass high to low transition, to read the data at output of

ADC.

6. STOP

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CODING

#include

//#define port P3

#define adc_input P1

//#define dataport P0

#define sec 100

sbit rs = P3^0;

sbit rw = P3^1;

sbit e = P3^2;

sbit wr= P3^3;

sbit rd= P3^4;

sbit intr= P3^5;

int a,b,c;

void delay(unsigned int msec );

void lcd_cmd(unsigned int item);

void lcd_data(unsigned int item);

void lcd_data_string(unsigned char *str);

void delay(unsigned int msec)

{

int i ,j ;

for(i=0;i

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for(j=0; j

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{

P2 = item;

rs= 1;

rw=0;

e=1;

delay(1);

e=0;

//delay(100);

return;

}

void main()

{

//adc_input=0xff;

lcd_cmd(0x38);

lcd_cmd(0x0E); //Display On, Cursor Blinking

lcd_cmd(0x01); // Clear Screen

lcd_cmd(0x06);

lcd_cmd(0x80);

rd=1;

wr=0;

wr=1;

while(intr==1);

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rd=0;

a=adc_input;

delay(1);

intr=1;

b=0x30+(a/0x0A);

c=0x30+(a%0x0A);

lcd_data(b);

lcd_data(c);

}

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FLOW CHART

Figure 8.3 Implementation of Interfacing ADC with Temperature Sensor

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PROTOTYPE

ISIS OUTPUT

Figure 8.5 Screen Shot of ISIS Emulator

INTERFACING LCD

Figure 8.4 Prototype of Experiment

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RESULT

Thus the Analog-Digital conversion using 8051 was successfully completed and the analog dataswere converted to its digital values.

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EX.NO:9

DATE:

DIGITAL CLOCK

AIM

To implement digital clock using seven segment display in microcontrollerP89V51RD2.

COMPONENTS REQUIRED

MicrocontrollerP89V51RD2


Seven segment display-6

Switch-2

4x4 Keypad

Connecting wires

ALGORITHM

Initialize Port 2(P2.0-P2.5) as enablepins to 6 seven segments.

Set Port3 for keypad scanning.

Initialize P2.6 and P2.7 as input which is used as switch for set mode and run mode

Initialize timer0 and timer1 in timer mode.

Set TL0=0X99 & TH0=0X0f1 to generate 0.004 second and set IE=0x82 to enabletimer0 interrupt and start timer0(TR0=1)

If run=0;within infinite loop clock starts running from 00:00:00

If set=0;enter second, minute, hour using keypad and assigned to s0,s1,m0,m1,h0 and

h1.

Within infinite loop clock starts running from the value i.e., set via keypad

Set TL1=0X0FD & TH1=0X4B to generate 50ms and repeat using for loop for about

20 times to generate one second

Each value in second is incremented with time delay of one second using timer1

When timer0 overflow ,it set TF0=1 which is raised as interrupt then executes

interrupt routine

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Within interrupt routine, again reload TL0=0x36 & TH0=0x0F6 and post increment

count variable

Then depending upon count ,it enable one of the 6 seven segment and display the

content in s/m/h variable

FLOWCHART

Figure9.1 Flowchart for digital clock

START

Initialize P2.0-P2.5 as enable pins to 6 seven

segments.Set Port3 for keypad scanning.

Initialize P2.6 and P2.7 as input connected to

switch for set mode and run mode

Initialize timer0 and timer1 in timer modeSet

TL0=0X99 & TH0=0X0f1set IE=0x82 and set

TR0=1

if (run=0)

if (set=0)

Start from 00:00:00

Enter s0, s1, m0, m1, h0, h1 using keypad andset values in for loop and starts from set value

callclockdelay()

& increment

callclockdelay() &

increment

YES

YES

NO

NO

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Figure9.2 Flowchart for display

Start ISR

Set TL0=0X99 & TH0=0X0f1

and initialize P1=0xff

Set P2.0 toP2.5 as zero.

Count++

Count=count%6

If count=0

If count=1

If count=2

If count=3

If count=4

P1=digi[s0];

P2.0 = 1;

P1=digi[s1]; P2.1

= 1; break;

P1=digi[m0];

P2.2 = 1;

break;

P1=digi[m1];

P2.3 = 1;

break;

If count=5

P1=digi[h0]; P2.4

= 1; break;

P1=digi[h1];

P2.5 = 1;

break;

YES

NO

YES

YES

YES

YES

YES

NO

NO

NO

NO

Return

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Figure9.3 Flowchart for one second delay

START

clockdela

Set TL1=0x0FD and

TH1=0x4B

Set TR1=1

while(TF1==0);

Yes

TR1=0; TF1=0;

increment i;

i=0

i

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CIRCUIT DIAGRAM

Figure9.4 Digital clock circuit diagram

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CODING

#include

voidclockdelay();

unsigned char count=0;

sbit enable_1 = P2^0;






sbit set = P2^6;

sbit run = P2^7;

sbit r1 = P3^0;

sbit r2 = P3^1;

sbit r3 = P3^2;

sbit r4 = P3^3;

sbit c1 = P3^4;

sbit c2 = P3^5;

sbit c3 = P3^6;

sbit C4 = P3^7;

voiddisp(int );

int keypad(void);

intgetkey();

unsigned char digi[]={0x0c0,0x0f9,0x64,0x70,0x59,0x52,0x42,0x0f8,0x40,0x50,0x46};

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int s0,s1,m0,m1,h0,h1;

inta,b,c,d,e,f;

int flag=0;

void main()

{

TMOD=0x11;

TL0=0x99;

TH0=0x0f1;

IE=0x82;

TR0=1;

if(set==0)

{

while(set==0);

do{

flag=0;

a=getkey();

if(a>=10)

{ a=10;flag=1;}

s0=a;

}while(flag==1);

do{

flag=0;

b=getkey();

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if(b>5)

{ b=10;flag=1;}

s1=b;

}while(flag==1);

do{

flag=0;

c=getkey();

if(c>=10)

{ c=10;flag=1;}

m0=c;

}while(flag==1);

do{

flag=0;

d=getkey();

if(d>5)

{d=10;flag=1;}

m1=d;

}while(flag==1);

do{

flag=0;

e=getkey();

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if(e>=10)

{e=10;flag=1;}

h0=e;

}while(flag==1);

do{

flag=0;

f=getkey();

if(e>3&&e=2)

{ f=10;flag=1;}

}

if(e2)

{f=10;flag=1;}

}

h1=f;

}while(flag==1);

while(1)

{for(h1=f;h1

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{for(s1=b;s1

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{

for(s1=b;s1

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{

for(h0=0;h0

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{

for(m0=0;m0

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while(TF1==0);

TR1=0;

TF1=0;

}

}

voidclockdisp() interrupt 1

{

TL0=0x99;

TH0=0xf1;

P1=0xff;

enable_1 = enable_2 = enable_3 = enable_4 = enable_5 = enable_6 = 0;

count++;

count=count%6;

switch(count)

{

case 0:

P1=digi[s0];

enable_1 = 1;

break;

case 1:

P1=digi[s1];

enable_2 = 1;

break;

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case 2:

P1=digi[m0];

enable_3 = 1;

break;

case 3:

P1=digi[m1];

enable_4 = 1;

break;

case 4:

P1=digi[h0];

enable_5 = 1;

break;

case 5:

P1=digi[h1];

enable_6 = 1;

break;

}

}

intgetkey()

{ int key=99;

while(key==99)

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key=keypad();

return(key);

}

int keypad(void)

{ r1=0; r2=1;r3=1; r4=1;

if(c1==0){ while(c1==0); return 7; }



r1=1; r2=0; r3=1; r4=1;

if(c1==0){ while(c1==0); return 4;}



r1=1;r2=1;r3=0;r4=1;




r1=1;r2=1;r3=1;r4=0;


return 99;

}

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SAMPLE OUTPUT

Figure 9.5 ISIS simulation output

RESULT

Thus digital clock using seven segment display in microcontroller P89V51RD2 was

simulated using ISIS and verified

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EX. NO:10

DATE : OBSTACLE DETECTOR USING IR SENSOR

AIM:

To design and implement obstacle detection by interfacing LCD and IR sensor using 8051

microcontroller.

Hardware Required:

16X2 Line LCD (LM016L).

IR Sensor.

PHILIPS P89v51RD2XX.

TOP2048 Programmer kit.

Power supply(5v).

Connecting wires.

Software Required:

Keil uvision 3.

ISIS Proteus Professional 7.

Topwin VER5.49.

IR (Infrared) Sensor

The basic concept of IR(infrared) obstacle detection is to transmit the IR signal(radiation) in a

direction and a signal is received at the IR receiver when the IR radiation bounces back

from a surface of the object. Here in the figure the object can be any thing which has certain

shape and size, the IR LED transmits the IR signal on to the object and the signal is reflected

back from the surface of the object. The reflected signals is received by an IR receiver. The

IR receiver can be a photodiode / phototransistor or a ready made module which decodes the

signal.

Fig 10.1 IR Sensor

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IR Transmitter

In general, the basic building block of any IR transmitter is modulation of the information

signal with carrier signal, because the receiver modules which are available off-the-shelf are

made for a particular carrier frequency. So it is clear that when you chose a particular IR

receiver module, you also need to transmit the the modulated wave with the same carrierfrequency of that of a IR receiver module.

IR Receiver

It is quite simple to construct a IR receiver with readily available off-the-shelf modules.

These modules are nothing but the IC packages, referred as TSOP(Thin small-outline

package). In this document, the receiver is designed for 38 kHz carrier signal, hence the IC

selected should work for the same frequency. The IC TSOP4838 will serve as a receiver

module, which is compatible with both TTL and CMOS logic. This means that we can

directly get digital signal from the receiver module and then connect it to the microcontroller.

ALGORITHM:

Initialize the Port1 for data pins of LCD.

Initialize the P2.4 for RS ,P2.5 for enable and P2.6 for RW pins of LCD.

Initialize the Port 2.7 for output pin of IR SENSOR.

Declare function delay(), lcdcmd(), lcddata(), lcddata_string() and IRSENSOR().

Call the command function lcdcmd() to send the commands to LCD

Call the IRSENSOR() function to check the obstacle present

If any obstacle present means the IR (P 2.7 ) output will be high signal and then

lcddata_string() will be called to display obstacle in LCD

Else the IR (P 2.7 ) output will be low signal and then lcddata_string() will be called

to display no obstacle in LCD

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Flow chart

Start

Initialize the Port1 for data pins of LCD

Initialize the P2.4 for RS ,P2.5 for enable and

Initialize the Port 2.7 for output pin of IR

Call the command function

lcdcmd

Call the

IRSENSOR

If output is

high?

Display Obstacle in LCD

Display no Obstacle in LCD

YES

NO

Stop

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Program:

#include

#define cmdport P2

#define dataport P1

sbit rs = cmdport^4; //register select pin

sbit rw = cmdport^6; // read write pin

sbit e = cmdport^5; //enable pin

sbit IR = cmdport^7;

void IRSENSOR();

void delay(unsigned int msec) // Function to provide time delay in msec.

{

int i,j ;

for(i=0;i

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void lcddata(unsigned char item) //Function to send data to LCD

{

dataport = item;

rs= 1;

rw=0;

e=1;

delay(1);

e=0;

}

void lcddata_string(unsigned char *str) // Function to send string to LCD

{

int i=0;

while(str[i]!='\0')

{

lcddata(str[i]);

i++;

delay(1);

}

}

void main()

{

lcdcmd(0x38); // for using 8-bit 2 row mode of LCD

delay(100);

lcdcmd(0x0E); // turn display ON for cursor blinking

delay(10);

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lcdcmd(0x01); //clear screen

delay(10);

lcdcmd(0x06); //display ON

delay(10);

lcdcmd(0x80); // bring cursor to position 6 of line 1

delay(100);

IRSENSOR();

}

void IRSENSOR ()

{

if(IR==0)

{

lcddata_string("no obstacle");

}

else

{

lcddata_string("obstacle ");

}

}

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CIRCUIT DIAGRAM:

Fig 10.3 IR Sensor Using 8051 Microcontroller

SAMPLE OUTPUT:

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Fig 10.4 Output of IR Sensor when no obstacle present

Fig 10.5 Output of IR Sensor when obstacle present

RESULT:

Therefore, obstacle detection by interfacing LCD and IR sensor using 8051 microcontroller.

has been executed successfully.

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EX NO:11

DATE:

INTERFACING LED WITH AVR

AIM

To write a program for interfacing LED with AVR microcontroller to Blink by using AVRstudio.

COMPONENTS REQUIRED

Microcontroller IC Atmega 16

Max 232 IC & 9pin RS232 Female connector

Bread board and connecting wires

Resistors 1K ohm,

Crystal oscillator 8 MHz

Capacitor 1F, 10 F, 33pF

LED 3mm - 8

THEORY

AVR MICROCONTROLLER

The AVR is a modified Harvard architecture 8-bit RISC single chip. The AVR was one of the

first microcontroller families to use on-chip flash memory for program storage, as opposed

to one-time programmable ROM, EPROM, or EEPROM used by other microcontrollers at thetime. Among the first of the AVR line was the AT90S8515, which in a 40-pin DIP package has

the same pin out as an 8051 microcontroller, including the external multiplexed address and data

bus. The polarity of the RESET line was opposite (8051's having an active-high RESET, whilethe AVR has an active-low RESET) but other than that, the pin out was identical.

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PIN DIAGRAM

FIG 11.1 Pin Diagram of ATMEGA16S

PIN DESCRIPTION

ATmega16 Microcontroller Pin Description

Pin 40Vcc

Vcc provides supply voltage to the chip.

The voltage source is +5V.

Pin 20Ground

Pins 19,18 : XTAL1 and XTAL

Pin 9Reset

It is an input pin and is active high (normally low.

The high pulse must be high at least 2 machine cycles.

FIG 11.2 Crystal Oscillator

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CIRCUIT DIAGRAM

FIG 11.3 Interfacing LEDS with ATMEGA16

CIRCUIT CONNECTION

Give the Vcc (5V) supply to the 40th

pin and ground to the 20th

pin of microcontroller.

Give the reset pin connections (reset switch, 10uF and 10k resistor) to the 9th

pin of the

controller as per the circuit diagram. Give the oscillator connections (8 MHz crystal oscillator and two 33pF capacitors) as per the

circuit diagram.

Connect the pins PB0 - PB7 to data line

PROGRAM

#include int main(void)

{

int a=0xFF, i=0;

DDRB=0xFF;while(1)

{

for(int j=0; j

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PROCEDURE

Write the seven segment coding for display in AVR Studio software and generate a hexcode.

Give the circuit connections as given above.

Interface the AVR microcontroller and LED.

Switch on the power supply and view the LED blinking.

ISIS EMULATION

FIG 11.4 Simulation Result of LED Interfacing

RESULT

Thus the program is written to interface LED with AVR microcontroller is verified and executed.

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EX NO: 12

DATE:

PROGRAMMING WITH ANALOG COMPARATOR OF AVR

AIM

To implement Analog Comparator of AVR.

DESCRIPTION

The Analog Comparator compares the input values on the positive pin AIN0 and negative pin

AIN1. When the voltage on the positive pin AIN0 is higher than the voltage on the negative pin

AIN1, the Analog Comparator Output, ACO, is set. The comparators output can be set to trigger

the Timer/Counter1 Input Capture function. In addition, the comparator can trigger a separateinterrupt, exclusive to the Analog Comparator. The user can select Interrupt triggering on

comparator output rise, fall or toggle.

FIG 12.1 Block Diagram of Analog Comparator

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SPECIAL FUNCTION IO REGISTER

FIG 12.2 SFIOR

Bit 3 ACME: Analog Comparator Multiplexer Enable

When this bit is written logic one and the ADC is switched off (ADEN in ADCSRA is zero), the

ADC multiplexer selects the negative input to the Analog Comparator. When this bit is writtenlogic zero, AIN1 is applied to the negative input of the Analog Comparator.

ANALOG COMPARATOR CONTROL AND STATUS REGISTER

FIG12.3 ACSR

Bit 7 ACD: Analog Comparator Disable

When this bit is written logic one, the power to the Analog Comparator is switched off. This bit

can be set at any time to turn off the Analog Comparator. This will reduce power consumption inactive and Idle mode. When changing the ACD bit, the Analog Comparator Interrupt must be

disabled by clearing the ACIE bit in ACSR. Otherwise an interrupt can occur when the bit ischanged.

Bit 6ACBG: Analog Comparator Bandgap SelectWhen this bit is set, a fixed bandgap reference voltage replaces the positive input to the Analog

Comparator. When this bit is cleared, AIN0 is applied to the positive input of the Analog

Comparator.

Bit 5ACO: Analog Comparator Output

The output of the Analog Comparator is synchronized and then directly connected to ACO. Thesynchronization introduces a delay of 1 - 2 clock cycles.

Bit 4 ACI: Analog Comparator Interrupt Flag

This bit is set by hardware when a comparator output event triggers the interrupt mode definedby ACIS1 and ACIS0. The Analog Comparator Interrupt routine is executed if the ACIE bit is

set and the I-bit in SREG is set. ACI is cleared by hardware when executing the corresponding

interrupt handling vector. Alternatively, ACI is cleared by writing a logic one to the flag.

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Bit 3ACIE: Analog Comparator Interrupt EnableWhen the ACIE bit is written logic one and the I-bit in the Status Register is set, the Analog

Comparator Interrupt is activated. When written logic zero, the interrupt is disabled.

Bit 2

ACIC: Analog Comparator Input Capture EnableWhen written logic one, this bit enables the Input Capture function in Timer/Counter1 to be

triggered by the Analog Comparator. The comparator output is in this case directly connected tothe Input Capture front-end logic, making the comparator utilize the noise canceller and edge

select features of the Timer/Counter1 Input Capture interrupt. When written logic zero, no

connection between the Analog Comparator and the Input Capture function exists. To make thecomparator trigger the Timer/Counter1 Input Capture interrupt, the TICIE1 bit in the Timer

Interrupt Mask Register (TIMSK) must be set.

Bits 1, 0ACIS1, ACIS0: Analog Comparator Interrupt Mode SelectThese bits determine which comparator events that trigger the Analog Comparator interrupt.

TABLE 12.1 ACIS0/ACIS1 SETTING

ANALOG COMPARATOR MULTIPLEXED INPUT

It is possible to select any of the ADC7..0 pins to replace the negative input to the AnalogComparator. The ADC multiplexer is used to select this input, and consequently, the ADC must

be switched off to utilize this feature. If the Analog Comparator Multiplexer Enable bit (ACME

in SFIOR) is set and the ADC is switched off (ADEN in ADCSRA is zero), MUX2..0 inADMUX select the input pin to replace the negative input to the Analog Comparator. If ACME

is cleared or ADEN is set, AIN1 is applied to the negative input to the Analog Comparator.

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Table 12.2 Analog Comparator Multiplexed Input

PROGRAM

#include // Most basic include files

#include // Add the necessary ones

#include // here

// Define here the global static variables

int My_global;

// Interrupt handler example for INT0

//SIGNAL(SIG_INTERRUPT0) {

}

// It is recommended to use this coding style to

// follow better the mixed C-assembly code in the

// Program Memory window//

void my_function(void) { // Put the open brace '{' here

asm("nop"); // Inline assembly example

}

// ***********************************************************// Main program

// ***********************************************************

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int main(void) {

DDRD=0X00; // ANI0,1 AS I/PDDRB=0X01; //PB0 AS O/P

ACSR=0X00;

while(1) { // REFLECT ACO BIT STATUS IN PB0

if(ACSR&(1

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EX NO: 13

DATE:

INTERFACING SEVEN SEGMENT DISPLAY WITH AVR

AIM

To write a program for interfacing seven segment display with AVR microcontroller to display

the numerical value and non numerical characters by using AVR studio.

COMPONENTS REQUIRED

Microcontroller IC Atmega 16

Max 232 IC & 9pin RS232 Female connector

Bread board and connecting wires Resistors 1K ohm,

Crystal oscillator 8 MHz

Capacitor 1F, 10 F, 33pF

Seven segment display 4

THEORY

SEVEN SEGMENT DISPLAY

A seven-segment display (SSD), or seven-segment indicator, is a form of electronic display

device for displaying decimal numerals that is an alternative to the more complex dot-

matrix displays. Seven-segment displays are widely used in digital clocks, electronic meters, and

other electronic devices for displaying numerical information.

A seven segment display, as its name indicates, is composed of seven elements. Individually onor off, they can be combined to produce simplified representations of thearabic numerals. Often

the seven segments are arranged in an oblique (slanted) arrangement, which aids readability. In

most applications, the seven segments are of nearly uniform shape and size (usuallyelongated hexagons, though trapezoids and rectangles can also be used), though in the case

of adding machines, the vertical segments are longer and more oddly shaped at the ends in an

effort to further enhance readability.

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FIG13.1 Indi

CIRCUIT DIAGRAM

FIG 13.2 Interfa

vidual Segment for Seven Segment Display

ing Seven-Segment Display with ATMEGA1

6S

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CIRCUIT CONNECTION

Give the Vcc (5V) supply to the 40th

pin and ground to the 20th

pin of microcontroller.

Give the reset pin connections (reset switch, 10uF and 10k resistor) to the 9th

pin of the

controller as per the circuit diagram.

Give the oscillator connections (8 MHz crystal oscillator and two 33pF capacitors) as per thecircuit diagram.

Connect the pins PB0 - PB7 to data line and PD0PD3 to control line of the seven segmentdisplay.

PROGRAM

#include // Most basic include files#include // Add the necessary ones

#include // here

#include

int DATA[4]={0x60,0xda,0xf2,0x66};

unsigned char i,j=0x01;

SIGNAL(SIG_INTERRUPT0) {

}

// Main program

int main(void) {

DDRB=0XFF;DDRD=0XFF;

while(1) {

// Infinite loop;for(i=0;i

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PROCEDURE

Write the seven segment coding for display in AVR Studio software and generate a hexcode.

Give the circuit connections as given above.

Interface the AVR microcontroller and seven segment displays.

Switch on the power supply and view the seven segment display.

ISIS EMULATION

FIG 13.3 Simulating Seven-Segment Display in ISIS

RESULTThus the program is written to interface seven segment displays with AVR microcontroller is

verified and executed.

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I SEM Lab - 8051, AVR

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