BCD TO SEVEN SEGMENT DISPLAY EMBEDDED C

BCD TO SEVEN SEGMENT DISPLAY

THEORY:

     A 7-segment display 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.

The seven segments are arranged as a rectangle of two vertical segments on each side with one horizontal segment on the top, middle, and bottom. The segments of a 7-segment display are referred to by the letters A to G, where the optional DP decimal point (an "eighth segment") is used for the display of non-integer numbers.

BCD I/P	SEGMENT O/P	DISPLAY
	g f e d c b a
0   0   0   0	0 1 1 1 1 1 1	0
0   0   0   1	0 0 0 0 1 1 0	1
0   0   1   0	1 0 1 1 0 1 1	2
0   0   1   1	1 0 0 1 1 1 1	3
0   1   0   0	0 1 1 0 0 1 1	4
0   1   0   1	1 1 0 1 1 0 1	5
0   1   1   0	0 0 1 1 1 1 1	6
0   1   1   1	0 0 0 0 1 1 1	7
1   0   0   0	1 1 1 1 1 1 1	8
1   0   0   1	1 1 0 0 1 1 1	9

CIRCUIT SCHEMATIC & OUTPUT:

PERIPHERAL OUTPUT:

SOURCE CODE:

#include<regx51.h>

sfr out=0xA0; //P3

sfr inp=0x90; //P1

unsigned char temp;

unsigned char const lookup[10]=

           {0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90};

void main()

{

out=0x00;

inp=0xFF;

while(1)

  {

     temp=inp & 0x0F;

     if(temp>=0x0A)

          out=0x00;

     else

          out=~(lookup[temp]);

  }

}