International Journal of Eletronis and Computer Siene Engineering Available Online at www.ijese.org ISSN- - Implementation of PIC Based LED Displays Htet Htet Thit San, Chaw Myat Nwe and Hla Myo Tun Department of Eletronis Engineering Mandalay Tehnologial University Abstrat- This paper explains the projet whih is a speial kind of LED Display Board for performing dane movement aording to the rhythm of musi. Nowadays, LED display boards are widely used in advertising and other appliations. LED display boards an also be used indoors or outdoors. The objetive of this system is to design a display panel by using several dozens of LED matrix display. The display pattern an desire to be hanged easily and modified by the user. This LED display board is overall in two major omponents; whih are the miroontroller and LED display panel. Miroontrollers with programs are developed to generate haraters and graphis for this module. In this system, when the LED display board is ON, it will display the messages and then dane movements by the rhythm of musi using a PIC miroontroller. It is not needed to hange the LED panel, only to hange the input data in PIC program. In this system, LED panel is ontrolled by a program in miroontroller from serial to parallel shift registers using the sanning method. PIC miroontroller is for generating the output signal to output display board by using a program. Then, it will be run on the LED display board. This is very useful in area like railway platforms, streets, banks, training institutes and other appliations to show data information on the large LED boards. As a result, this LED display board is useful as indoors or outdoors as it is also eonomi. This display onsists of maximum bright LEDs whih are rotated to show the display. In this system, this display an show data information whih will require a whopping LEDs. Therefore hardware and ost minimization is ahieved. PIC Basi Pro programming language will be used in PIC miroontroller. The simulation result will be tested with Proteus Eletroni Simulation Software. Keywords: LED display board, PIC F Miroontroller, PIC Basi Pro Programming, Proteus I. INTODUCTION Nowadays, uses of LEDs are inreasingly made in many appliations as a replaement for traditional light bulbs. It is a way of visual information where large LCD and other display beome too muh expensive. The displays are ommonly seen single olored or having or olors. This system supports an effiient and salable approah to LED displays. This system is omprised of a red olor matrix display panel. It also inludes an exeutive program that runs on the PIC miroontroller for the display ontrol of data information on the display board. LEDs provide several advantages over traditional light bulbs, suh as small size and longer life. A red olor LED an be used to advertise even day-light onditions. The LED display board displays images and messages entered by using a miroontroller that initializes the led driver and rhythm of musi drives together with this displays by using musi iruit. Today, LED displays are very popular of displaying information beause it allows both stati and animated images. In this projet, the system is based on LED display board that is able to perform dane movement aording to the rhythm of musi. In many appliations, LEDs must be driven with intelligent ontrol iruitry. LED displays have been enountered in the publi plaes, building mahinery operator panel sreens and alongside highways displaying advertisements on large display panels. In this work, about the basi struture of a monohrome (single olor) LED matrix and it onnets with a miroontroller to display stati haraters and symbols will be disussed. PIC miroontroller is used but this tehnique is appliable to any other PICs that have suffiient I/O pins to drive the LED matrix. Furthermore, it is also neessary to adapt the driver for LEDs in different brightness groups by means of hardware seletion. Displaying messages on a x LED matrix will be disussed. In this iruit, the simple produer will be used. When it is power on, the LED display board is shown messages and then performed dane movement aording to the rhythm of musi. This tehnique will be demonstrated for performing dane movement using musi ISSN: -/V-N--
IJECSE, Volume, Number Htet Htet Thit San et al. and an be implemented for srolling in other appliations. The program for PIC F is used as a heart to ontrol for this system and is developed and written with PIC Basi Pro Programming Language. The system blok diagram is shown in Figure. Figure : Blok diagram of LED display Board for advertisement using miroontroller Literature eview Multi Level LED dot matrix display panel by Kim Ling Sheng The author mentioned that In this design tehnique, piees of x LED dot matrix is used to design the display panel. This display panel is programmed by using Assembly language to program the PIC FA. It displayed alphanumeri and graphi harater. II. Hardware Components The first step was the evaluation of the requirements that needed to be met. The tehnial features for physial operation and possible appliations of the system were disussed. Also, the funtional speifiations outlined of the purpose and features of the design would finally fulfill were also addressed. The main ontrol iruit was initially tested with Proteus software beause the miroontroller ports used for various tasks would ultimately hange as the work developed. Thus, the pin onnetions ould easily be hanged as required. The miroontroller requires very few external portions for typial operation. An illuminated display usually onsists of smaller modules arranged together to form a larger sreen, eah module usually onsisting of a x matrix of LEDs. This idea is used in this design of x LED matrix display. In this board, bright LEDs matrix panel has on board ontroller iruitry designed. The goal of this paper is to reate a display performing dane movement aording to the rhythm of musi. ed LEDs are used to design. In this LED display board, many LEDs are onneted in serial form. The x LED display panel with LEDs are arranged in rows and olumns struture is shown in figure. The rhythm of musi using sound iruit is reated the pleasant sound as soon as data is displayed together with sound in this system. This system is a fantasti way to illuminate any kind of sign and other appliations. A. Expansion of LED Usage In seleting the LEDs to use for the display the most available units were hosen for their omfort of supply. To reate a large matrix that forms the display sreen was needed by these units. The modules of this design are the x dot matrix units whih are widely available in a variety of sizes. Fig shows the onfiguration of this x dot matrix unit. These displays were also preferred as they have pins that are onneted in a similar design to integrated ISSN: -/V-N--
Implementation of PIC Based LED Displays iruit. The pin onfiguration made it easy to onnet the LED modules on board ontroller iruitry designed, as well as making onnetions to the pins straightforward. The matrix LEDs has a ommon anode onnetion for eah of the olumns and a ommon athode for eah of the rows. Nowadays, the use of LEDs matrix for displaying system is made inreasingly with its usage expanding. LED displays an be found in airports, railway stations, shopping malls, hospitals and et. A result of its ability to onvey information to large audienes quikly and effiiently is been by the usage of LED display. LED displays are often ontrolled by digital tehnology the information, so it an swiftly and easily be updated. The LED displays have led to a great flexibility in many appliations. An additional advantage of using this system; LEDs are a very effiient form of illumination. Fig. Configuration of x dot-matrixes This system has been developed whih allows for LED design based on miroontroller and other omponent seletions for these design. The PIC miroontroller is used to ontrol all funtion of this system. Large sized LED display panel is used to display data or information in publi area. In this board, bright LEDs matrix panel has on board ontroller iruitry designed. It has otal transeiver (buffer), shift registers, transistor (deoder) and LED display drivers on board ontroller iruitry. This system is implemented by LED board beause it is easy to onstrut than other LED Dot Matrix. This idea is used in this design of x LED matrix display. In order to onnet a miroontroller with serial port to LED display panel, otal buffer is used for two way asynhronous ommuniation between data buses. Typially, the serial port of PIC miroontroller is used with a buffer to provide a serial ommuniation link to another unit. All shift registers are asading to run through a same serial lok. The similar olumns (athodes) of all serial matries are onneted together so that there are ombined olumns in totals. The olumns of LEDs are driven individually by shift registers. The shift registers is to onvert the serial data input to parallel data output. B. Serial-In Parallel-Out Shift egisters: The HC IC is an -bit shift register and this IC an shift bits to the outputs with only wires, that are Data (Ds) and two shift inputs (SH-CP, ST-CP). In order to display the LEDs in -moduled is ontrolled by multiplexing of the I/O to the miroontroller is required. The HC IC is a series of serial-in to parallel-out shift register used to onvert serial bits to a parallel output port to the LEDs. By shifting the shift registers (HC) together, the large parallel output port required to address eah LED aomplish. This means the serial output of the shift register sequene is asaded to form the input of the next shift register. The shift registers used are ahc, serial-in -bit parallel-out IC, whih is shown in Fig.. ISSN: -/V-N--
/C /C /C /C /C /C IJECSE, Volume, Number Htet Htet Thit San et al. Fig. Conversion from serial to parallel data The devies have two separate registers within it, a shift register and a storage register; eah register is provided with a separate loking input: SH_CP and ST_CP. In operation, data is fed serially into the register through data soure (DS) pin and is shifted on the positive-going transitions of the SH_CP input when onneted in this asading manner. The parallel outputs of the shift registers are not rated to handle enough urrent to illuminate the LEDs that they ontrol. To get full illumination of the LEDs in the system, eah will be pulsed with ma. As a result, the transistor drives LEDs drivers. LED drivers are used to ontrol the row of LED modules. These ontrol the intensity and the brightness of the display. The row (anodes) are driven separately and one driver iruit has separated hannel beause it drives rows of LEDs and hene there are rows altogether. LED drivers are used to supply eah all the LEDs with enough urrent to fully illuminate them. The LED drivers used are MW that ontain to ontrol the intensity and brightness of the display. It ontrols the olor of the display and deides whih LED is to be lighted to display speifi haraters. The MW is omprised of eight soure urrent transistor array. III. System Design As the tehnology and light output of LEDs ontinues to improve, appliations for olor and white brightness LEDs are expending into entirely new markets. LED display board is a x red LED design for wide range of appliations. This LED board is divided into portions. This system is to perform dane movement aording to the rhythm of musi. Advertising is one way that this has been ahieved. It is very onvenient by seeing from distant plae people. The system begins with an introdution to the onept of LED display board and how it may be onstruted LED display and PIC miroontroller. A. Software design for the System As shown in fig, the onstrution of LED display board onsists of two parts: the hardware and software implementations. Both software and hardware will be aomplished using PIC F miroontroller. The miroontroller was hosen for reasons of speed memory storage, number of I/O ports and digital ports ability. This program is written by PIC basi pro language beause it is easy to understand than other programming languages. This struture is applied in serial form. The LED matrix used in this work is of size x. In below, how to display in a standard x pixel format is disussed.figure shows whih LEDs are to be turned on to display the row value of eah olumn for displaying images and figure shows the program flowhart of the LED displays. Figure. ow value of eah Column for Displaying Images ISSN: -/V-N--
Implementation of PIC Based LED Displays Figure.The Program Flowhart of the System B. Hardware Design for the System In this system, maximum LEDs will be lighted at one. The LED display board is displayed images for performing dane movement aording to the rhythm of musi when it is power on. The omplete iruit diagram of the proposed system is depited in figure. PIC F miroontroller is used as ontrol unit. PIC F miroontroller onsists of pins. It ontains Input/output (I/O) ports with I/O pins. Those input/output ports are Port A, B, C, D and E. The next pins are two Vss, two Vdd, two lok input pins and master lear(mcl) input. By using the sophistiated PIC F, the LED display board uses fewer omponents that would have been required in the system. This miroontroller an be reprogrammed beause it uses flash-read only memory for program storage. The LED display board ontains power supply unit, PIC F and other omponents. The power supply unit is a ombination of a MHz rystal, two pf apaitors.v input voltage is supplied to the power supply unit and the output is v. Pin and of the F are onneted to the V while pin and are onneted to the ground. Pin and are onneted to MHz osillating rystal. In this system, POTC and POTD are used for output pins and POTB is used for input. POTC and POTD are onneted to the transeiver. POTB pinis onneted to the sounder. Port C pin, and are onneted to input, and of the HC while Port D pin and are onneted to input and of the HC. Enable and are always enabled by onneting them to the V. The V power supply is onneted to Vdd, Vss and ground. ISSN: -/V-N--
IJECSE, Volume, Number Htet Htet Thit San et al. Figure. Overall Ciruit Diagram for the LED Displays IV. Software and Hardware esult A. Software result In this LED displays, Pi Basi Pro Language is used for PIC F miroontroller beause this ompiler software is easy to install and its ommands are easy to understand. The software is required for displaying dane movement aording to the rhythm of musi. A miroontroller is nothing without software to run it. To program the PICs, a binary file of oded s and s is required. This system is simulated by using Proteus software and the programming language used is Pi Basi. The program flowhart of the LED displays is illustrated in figure. The data information is stored in EEPOM. PIC miroontroller initializes the data information when it is power ON. It needs to set AM for lear and set the san time is. Firstly, the sound is OFF, the program will be loaded images MTU and EC. After loading: it means that the sound is ON; the images will be loaded by displaying dane movement aording to the rhythm of musi. The aim was to make sure that all the LEDs on the display panel was lighting orretly. In figure, the tested iruit an suessfully display images on the LED display panel but this system is not available to test by using many LED display panels and all of ontained ICs in Proteus. Figure : Simulation result of LED display Board for Advertisement ISSN: -/V-N--
Implementation of PIC Based LED Displays B. Hardware result A display panel onsists of modules arranged together to form a larger sreen, eah module usually onsisting of a x matrix of LEDs. LEDs display board is omposed with many red LEDs. This display board has rows and olumns (LEDs).To get full illumination of the LEDs, eah will be pulsed with ma.the maximum required urrent isma. In this system, LEDs will be lighted at one. Fig shows the implementation of the designed LED display board for advertisement. Figure. Test esult for some LED Displays This design an be divided into several modules. They are LEDs matrix, sound system and power supply. There are some devies and omponents used in the in the design to implement eah unit. These devies used in this system are as follows; F miroontroller LEDs matrix Otal bus transeiver(hc) Shift register(hc) LED driver(mw) Power supply In this LED displays, PIC Basi Pro Language is used for PIC F miroontroller beause this ompiler software is easy to install and its ommands are easy to understand. The software is required for displaying dane movement aording to the rhythm of musi. V. Disussion and Conlusion This display board is a single olor LED matrix board whih an be used for advertising and other display appliations. In this paper, PIC F miroontroller is used to ontrol the display board. ed LEDs are used on board ontroller iruitry designed and it is onneted in serial form. Although many LED Dot Matries have in eonomi; the LED display board is done. Beause the board is easy to set up for wide range of appliations today. The designing proess of this system inludes the hardware and software portions. In software portion, a program of PIC miroontroller is written in PIC Basi Pro language and it will ontrol all funtion of display board. In hardware, LED displays and sound iruit are inluded. This paper is designed to onstrut using with the devies whih an buy easily in the market, easy to apply with a person who interested in eletroni field. In onlusion, the iruit diagram is omplex but the design and onstrution are quite simple and there is no ompliation. ed LEDs are used to reate the display board and these LEDs are onneted in serial form. This LED display board is basially low ost. Sine miroontroller IC is used in this display iruit, the iruit is more ISSN: -/V-N--
IJECSE, Volume, Number Htet Htet Thit San et al. ompat and power onsumption is very low. It needs software for hanging the information to display. This LED display board is also widely used in advertising and information devies. This display board an be ommerially produed by modifying. This onludes the onstrution and programming of the LED display board. ACKNOWLEDGEMENT The author would like to thank her supervisor, head and all her teahers from Department of Eletroni Engineering, Mandalay Tehnologial University who gave good suggestions, guidane and supervision for supporting this researh. EFEENCES [] Kin Ling Sheng, Multi level LED Dot matrix Display panel, (). [] Dogan Ibrahim, Projets Using PICBasi and PICBasi Pro,MPG Books Ltd,Great Britain, (). [] Anonymous,PiBASIC Pro Compiler, Miro Engineering Lab In., (). [] Mousa KadhimWali, Design and Implementation of Eletroni Board Advertisement Based on Miroontroller PICF and Multi Charater Button Keypad, Eng. &Teh.Journal, Vol., No, (). [] Anonymous, PICFX Data Sheet, DSF, Mirohip Tehnology In., (). http://www.mirohip.om/downloads/en/devie Do/ f.pdf [] Embedded Lab., Lab : Solling text message on an LED dot-matrix display, Provided by zeedynami Themes, (). [] YAHAYA N. YUSUF, MICOCONNTOLLE BASED LED DISPLAY BOAD,(). [] SDM PGB-OSABS-, Lighting up the world one diode at a time, SANDA Eletroni om Ltd. [] D M K D Dissanayake and Lelwala, Constrution of an SMS Operable LED Display Panel, (). [] P Full olor Led Advertising Displays with High esolution -K. http://www.hinaledsreens.om /pdf/ [] NXP semiondutors, HC Datasheet, to line deoder/demultiplexer; inverting, June (). http://www.nxp.om [] Anonymous: Datasheet of MW P Channel Enxanement Mode MOSFET, Globalteh Semiondutor orporation, (). http://www.gs-power.om [] Anonymous: Datasheet of HC Otal bus transeiver:-state, Phillips Semiondutors Corporation,(). http://www.semiondutors.philips.om [] Anonymous: Datasheet of HC -bit serial in, serial or parallel out shift register with output lathes;-state,nxp Semiondutors Corporation,(). http://www.nxp.om ISSN: -/V-N--