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PROJECT-ASSOCIATESE

M.GANESH
P.NIVEDITHA
G.MANOHAR
B.NAVEEN KUMAR REDDY
MD RAHEEM PASHA

SRI KOTTAM TULASI REDDY MEMORIAL COLLEGE OF ENGINEERING
KONDAIR,ITIKYALA MANDAL MAHABOOB NAGAR

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ABSTRACT

The aim of this project is to scroll message on LED from an KEY BOARD and it is achieved by making an interface from KEY BOARD to an led using ARM processor.

Generally a situation may come where we need to display message from our keyboard on to LED directly hence our project satisfies that . here we are going to make use of an microcontroller which is having an ARM processor .ARM is abbreviated as ADVANCED RISC MACHINE .RISC means REDUCED INSTRUCTION SET its an advanced technology the keyboard is being interfaced to our microcontroller using an serial communication MAX232 protocol and all the message that is input at the keyboard is fed in to microcontroller which then processes it and then send to LED and LED displays the message that is entered from keyboard



1.1 INTRODUCTION:

The aim of this project is to scroll a message on LCD display from a PC or a key board. This scrolling message board is not a simple message box. Instead of showing a static text,It scrolls the text to maximize visitors attention.Generally a situation may come where we need to display message from our keyboard on to LCD directly and it is achieved by making an interface from pc to an LED using “ARM processor”. ARM is abbreviated as ADVANCED RISC MACHINE


1.3 OPERATION:-


 Switch on the power supply to the transmitter section after making necessary connections. A 230V/50Hz ac is stepped down to 12V/50Hz ac.tis is voltage is fed to a bridge rectifier an filter circuit.
 The output of filter circuit is fed to IC7812&IC7805 ,the output of 7805 inturn is connected to ARM controller module which works with +5v dc supply.
 The o/p from pc is given to the i/p of the MAX232,the power supply is given to the pin no 16(Vcc) & pin no 15(GND),
 The o/p from the pc is applied to the i/p of the MAX 232 at the pin no 13(RIN)&14(TXOUT).The o/p from the MAX 232 is obtained at the pin no’s 11(T1IN),12(R1OUT),10(T2IN),9(R2OUT).
 The o/p from the MAX232 is given as the i/p to the ARM controller.
 The power supply to ARM controller is given to the Vcc at the pin no’s (7,23,43,51) & GND at the pin no’s(6,25,42,50).The o/p from the MAX 232 has been given to the P0.0 –TXD0(pin no 19),P0.1-RXD0(pin no 21),P0.8-TXD1(pin no 33),P0.9-RXD1(pin no 34).The crystal oscillator is connected to the pin no 3 (RTCXTL1)&pin no 5 (RTCXTL2) to the ARM controller.
 The o/p of the ARM controller is applied to LCD.
 Tthe power supply is given to the pin no 2 to Vcc and 1 to GND,the o/p from the ARM controller is applied to i/p of the lcd pin no’s from 4 to 14 .Pin no 4 is connected to pin no 37 (P0.11-CTS1/CAP1.1/SCL1),pin no 5 is connected to pin no 38(P0.12-DSR1/MAT 1.0/AD 1.3) ,pin no 6 is connected to pin no 39(P0.13-DTR1/MAT 1.1/AD 1.4),pin no 7 is connected to pin 16(P1.16-TRACEPKT0), pin no 8 is connected to pin 12(P1.17-TRACEPKT1), pin no 9 is connected to pin 8 (P1.18-TRACEPKT2), pin no 10 is connected to pin 4(P1.19-TRACEPKT3), pin no 11 is connected to pin 48(P1.20-TRACESYNC), pin no 12 is connected to pin 44(P1.21-PIPESTAT0), pin no 13 is connected to pin 40(P1.22-PIPESTAT1), pin no 14 is connected to pin 36(P1.23-PIPESTAT2).
 Finally the o/p is display on the LCD screen.


1 Introduction:
The input to the circuit is applied from the regulated power supply. The a.c. input i.e., 230V from the mains supply is step down by the transformer to 12V and is fed to a rectifier. The output obtained from the rectifier is a pulsating d.c voltage. So in order to get a pure d.c voltage, the output voltage from the rectifier is fed to a filter to remove any a.c components present even after rectification. Now, this voltage is given to a voltage regulator to obtain a pure constant dc voltage.


2.2 Transformer:

Usually, DC voltages are required to operate various electronic equipment and these voltages are 5V, 9V or 12V. But these voltages cannot be obtained directly. Thus the a.c input available at the mains supply i.e., 230V is to be brought down to the required voltage level. This is done by a transformer. Thus, a step down transformer is employed to decrease the voltage to a required level.
2.3 Rectifier:
The output from the transformer is fed to the rectifier. It converts A.C. into pulsating. D.C. The rectifier may be a half wave or a full wave rectifier. In this project, a bridge rectifier is used because of its merits like good stability and full wave rectification.
2.4 Filter:
Capacitive filter is used in this project. It removes the ripples from the output of rectifier and smoothens the D.C. Output received from this filter is constant until the mains voltage and load is maintained constant. However, if either of the two is varied, D.C. voltage received at this point changes. Therefore a regulator is applied at the output stage.
2.5 Voltage Regulator:
As the name itself implies, it regulates the input applied to it. A voltage regulator is an electrical regulator designed to automatically maintain a constant voltage level. In this project, power supply of 5V and 12V are required. In order to obtain these voltage levels, 7805 and 7812 voltage regulators are to be used. The first number 78 represents positive supply and the numbers 05, 12 represent the required output voltage levels.A variable regulated power supply, also called a variable bench power supply, is one where you can continuously adjust the output voltage to your requirements. Varying the output of the power supply is the recommended way to test a project after having double checked parts placement against circuit drawings and the parts placement guide.
This type of regulation is ideal for having a simple variable bench power supply.Actually this is quite important because one of the first projects a hobbyist should undertake is the construction of a variable regulated power supply. While a dedicated
supply is quite handy e.g. 5V or 12V, it's much handier to have a variable supply onhand, especially for testing. Most digital logic circuits and processors need a 5-volt power supply. To use these parts we need to build a regulated 5-volt source. Usually you start with an unregulated power supply ranging from 9 volts to 24 volts DC (A 12 volt power supply is included with the Beginner Kit and the Microcontroller Beginner Kit.). To make a 5 volt power supply, we use a LM7805 voltage regulator IC (Integrated Circuit). The IC is shown below.