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A BSTRACT
This project report gives us an idea about displaying messages and animated images on the Display Board; First of all we design a circuit that works as a driver between the computer and the Display Board that takes input from computer in the form of binary numbers and using these binary numbers, it light the led’s of the Display Board that are necessary for our desired message or desired images. Temperature sensor records the temperature from the environment and displays it on the Board and a clock IC is used to display time on the Board .All these circuits take inputs from serial port or parallel port using language C++, work on these inputs and give result on Board
Certificate of Approval
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This project report is submitted to the panel for approval
______________________
Dr. Javaid Khurshaid (Supervisor)
3.5:Displayofworld(Pakistan)ontwoDotmatrixesBoard:.................................................................18 3.6:PseudocodeofworldPakistanontwoDots–matrixesboard:.......................................................19 3.7:ConnectingMultipleDotmatrixes:.................................................................................................21 3.8:CircuitDiagramofmultiplelinesoutputsdecoder:.........................................................................21 3.9:AnimatedImageandmessageonBoard:........................................................................................22
AppendixA:(8bitsdata,256CombinationsofBinarynumbers):..............................................................22
ListofFigures
Figure1(DotmatrixColumns)......................................................................................................................1
Figure2(PhysicalPictureofDotmatrix).......................................................................................................2
Figure3(InternalStructureofDotmatrix)....................................................................................................2
Figure4(ParallelPortConnections)..............................................................................................................6
Figure5(ParallelPortConnectionswithDotmatrix)....................................................................................6
Figure6(PhysicalShapeofDM74LS154).....................................................................................................11
Figure7(ConnectionsDiagramofDM74LS154)..........................................................................................12
Figure8(LogicDiagramofDM74LS154)......................................................................................................13
Figure9(TwoDotmatrixConnectionswithDM74LS154)..........................................................................14
Figure10(MovementsofSixteenColumnsByDemultiplexer)...................................................................16
Figure11(FlowGraph)................................................................................................................................17
Figure12(CharacterbyCharactermovementofPakistan)........................................................................18
Figure13(MultipleOutputsofDemultiplexer)...........................................................................................21
Figure14(AnimatedImageonDisplayBoard)............................................................................................22
Introduction: Electronic Banner is a hardware system that displays our information instantly from a computer, it can also function as a standalone message display, and it is for indoor or semi-outdoor applications. It can be programmed by using the parallel ports, and we can mount it on a wall, it can be programmed through the programming software using language C++. The basic unit is the Dot matrix, with the help of other component such as Demultiplexers, transistors, PCI card, and others, it can display text, characters, symbols, scrolling text, small images, animation and graphic and other advertisements. Date and time can also be displayed on it. Using temperature sensor, temperature sensor record temperature from environment and displayed it on Board,
Dot Matrix display board is simply a grid of LEDs. The combination of matrixes can be used to perform some specific task or some displaying functionalities. Combining the 64(sixty four) Dot- matrixes, the size of Board becomes 6464=4096 pixels. By arranging these 88 Dot-matrixes in a square shape or rectangle shape we define the numbers of rows and columns of Board. Combining the Dot-matrixes in square shape dimensions of the Board will be 64*64. It means 64 rows and 64 columns
Characters size of message will be 57 =35 pixels; it means that 7 rows and 5 columns. Small characters messages can be displayed on it. Small characters size will be 54 =20 pixels, 5 rows and 4 columns.
Chapter1:(Hardware)
1.1:DescriptionofDotMatrix(8*8):
Dot- matrix (88) is a grid of 64 led’s.This consists of an 8 x 8 dimension LED matrix. It is used for display; any message can be display on it and message character size is 57 pixel. Animation can be done by using its pixels, animated images, and text messages in any language, numbers and characters can be display on it. Its pixels can be controlled directly from parallel ports and its pixels can also be controlled using any decoder or any demultiplexer. Multiple Dot-matrixes can be connected using decoders or demultiplexers. Large number of Dot- matrixes can be connected by the concatenation of multiple demultiplexers. By using transistors its brightness can be improved
1.2:ControllingColumnsofDotmatrix(8*8):
To control one column of Dot matrix (88) one bit should be 0 or low ( from PortA, or PortB, or PortC ), from which port where the pins of Dot matrix that control the columns are connected. Moving the columns of Dot matrix (88) through Column One to 8th^ , every time change one bit continuously, from the bits that control the columns pins of Dot matrix. From these three ports one port is used to control the positive pins of Dot matrix on which the positive data (11111111) can be send on it. we can program these bits to display our required messages or images and other port is used to control the columns from columns one to column eight, On these ports from parallel port, 8bit data can be send every time. We can change only 8bits continuously, not more than 8 bits
MoveStart
Figure1(DotmatrixColumns)
1.4:PinnumbersofDotmatrix(8*8)
Serial number
Pins numbers for (+voltage)
Pins numbers for Green color
Pins numbers for Red color
Table1(PinNumbersofDotmatrix(88))*
A Dot-matrix (8*8) has 24 pins, 8 pins used for positive voltage, 8 pins are used for Green color and these also used to move the columns \characters in a Green color and 8 pins are used for Red color and these pins also used to move the \characters in a Red color. The pins that are used for positive voltage are directly connected to parallel port and the other pins of each dot-matrix are controlled by driver (demultiplexer).
1.5:PinNumbersofDotMatrixtolightled’sinGreenColor
+Voltage column8 column7 column6 column5 column4 column3 column2 column
Table1(PinNumbersofDotmatrix(88)forGreenColor)* The Positive voltage is applied on the pin numbers (22, 19, 16, 13, 3, 6, 9, and 12) it means that (11111111) is send on these pins and on the other hand negative voltage is applied on pin numbers (24, 21, 18, 15, 1, 4, 7, 10 ), it means that (00000000) is send on these pins, then all the pixels (Led’s) of Dot- matrix will be ON in a GREEN color. By changing these bits we can ON required pixels (Led’s) for specific message or image. In the squares of above table, each square has two pins, by sending data on these two pins the specific Led will be ON.
1.7:Parallelportconnections:
Figure4(ParallelPortConnections)
1.8:ParallelportconnectionswithDotMatrix:
Dot Matrix(88)*
22 19 16 13 3 6 9 12
24 21 18 15 1 4 7 10
(^2524) (^2322) (^2120) (^1918) (^1716) (^1514)
(^1312) (^1110) (^98) (^76) (^54) (^32) 1
23 20 17 14 2 5 8 11
These pins are for Red color
For Green color
Serial port
Figure5(ParallelPortConnectionswithDotmatrix)
1.9:Pseudocodeofdisplayingworld“PAKISTAN”onDotMatrix
While (!kbhit())
// First time we send the code: 1 on serial port, this code ON the LED,s of Dot Matrix first column that was necessary to display “P” first column
//Second time we will have to ON the LED,s of Dot Matrix of first and second columns.That was necessary for “P”. Now this time, we shift the previous code to second column and new data was sent on the first column. The LED,s of both columns that was necessary for “P” will be ON
Third time, column 1, column 2, and column 3 will be O
Seven time, “P” will be shifted on next column and the next column will be ON for next character. every time, one column remains blank between two columns
Data will be shifted on column 8
And so on, in this way the data on the last column will be deleted and next time the shifted data will be appear on the Dot matrix and so on, in this way all character will be display one by one on Dot Matrix
// End of while Loop
Figure7(ConnectionsDiagramofDM74LS154)
In the decoder, the ABCD are the control bits, when ABCD is 0001, only the Y1 AND gate has all inputs high, therefore only the Y1 output is high. If ABCD changes to 0100, only the Y AND gate has all inputs high; as a result, only the Y4 output goes high. If we check the other ABCD possibilities, (0000 to 1111), we will find that the subscript of the high output always equals the decimal equivalent of ABCD. For this reason, the circuit is sometimes called a binary to decimal decoder. Because it has 4 input lines and 16 output lines, the circuit is also known as a 4 lines to 16 lines decoder
2.5:LogicDiagram:
From the logic diagram, it was seen that when input 0 (0 0 0 0) is given from any of the serial ports (PortA, or PortB,or PortC ) to D C, B, A respectively, then on output side pin no 0 would be Low and all other output pins are High, this Low output pin is used to ON all the bits of first column of two connected Dot-matrix by sending 255 on the positive connections of Dot-matrix that are connect to any of the other serial ports ( PortA, or PortB, or PortC). By changing the inputs bits the columns of the Dot-matrix can be shift continuously from column no 1 column no 16
Figure8(LogicDiagramofDM74LS154)
2.6:FunctionTable:
Table3(FunctionTableofDM74LS154)
