gistfile1.c

#include <stdio.h>
#include <stdlib.h>
//#include <conio.h>
#include <time.h>
#include <windows.h>
#include <string.h>
#include <math.h>

//initialise variables to make the GPIO easier to use
//uses BCM_GPIO mode for the pins
//                            H   C   P   E   I   O   J   M
const int positivePins[8] = {21, 24, 19, 12, 04, 13, 17, 05};

//                            D   K   L   G   N   F   B   A
const int negativePins[8] = {25, 27, 22, 20, 06, 16, 23, 18};

//letters created as a test
const unsigned char characters[][8] = {{0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000}, // space
                                       {0b00010000, 0b00010000, 0b00010000, 0b00010000, 0b00010000, 0b00000000, 0b00010000, 0b00000000}, // !
                                       {0b00101000, 0b00101000, 0b00101000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000}, // "
                                       {0b00000000, 0b00101000, 0b01111100, 0b00101000, 0b00101000, 0b01111100, 0b00101000, 0b00000000}, // #
                                       {0b00010000, 0b00111100, 0b01010000, 0b00111000, 0b00010100, 0b01111000, 0b00010000, 0b00000000}, // $
                                       {0b00000000, 0b01000100, 0b00001000, 0b00010000, 0b00100000, 0b01000100, 0b00000000, 0b00000000}, // %
                                       {0b00110000, 0b01001000, 0b01000000, 0b00100000, 0b01010100, 0b01001000, 0b00110100, 0b00000000}, // &
                                       {0b00010000, 0b00010000, 0b00010000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000}, // '
                                       {0b00010000, 0b00100000, 0b00100000, 0b00100000, 0b00100000, 0b00100000, 0b00010000, 0b00000000}, // (
                                       {0b00010000, 0b00001000, 0b00001000, 0b00001000, 0b00001000, 0b00001000, 0b00010000, 0b00000000}, // )
                                       {0b00000000, 0b01010100, 0b00111000, 0b01111100, 0b00111000, 0b01010100, 0b00000000, 0b00000000}, // *
                                       {0b00000000, 0b00010000, 0b00010000, 0b01111100, 0b00010000, 0b00010000, 0b00000000, 0b00000000}, // +
                                       {0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00010000, 0b00010000, 0b00100000}, // ,
                                       {0b00000000, 0b00000000, 0b00000000, 0b01111100, 0b00000000, 0b00000000, 0b00000000, 0b00000000}, // -
                                       {0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00000000, 0b00010000, 0b00000000}, // .
                                       {0b00000000, 0b00000010, 0b00000100, 0b00001000, 0b00010000, 0b00100000, 0b01000000, 0b00000000}, // /
                                       {0b00011000, 0b00100100, 0b00100100, 0b00100100, 0b00100100, 0b00100100, 0b00011000, 0b00000000}, // 0
                                       {0b00010000, 0b00110000, 0b00010000, 0b00010000, 0b00010000, 0b00010000, 0b00111000, 0b00000000}, // 1
                                       {0b00110000, 0b01001000, 0b00001000, 0b00010000, 0b00100000, 0b01000000, 0b01111000, 0b00000000}, // 2
                                       {0b00110000, 0b01001000, 0b00001000, 0b00110000, 0b00001000, 0b01001000, 0b00110000, 0b00000000}, // 3
                                       {0b00001000, 0b00011000, 0b00101000, 0b01001000, 0b01111100, 0b00001000, 0b00001000, 0b00000000}, // 4
                                       {0b01111000, 0b01000000, 0b01000000, 0b00110000, 0b00001000, 0b01001000, 0b00110000, 0b00000000}, // 5
                                       {0b00110000, 0b01001000, 0b01000000, 0b01110000, 0b01001000, 0b01001000, 0b00110000, 0b00000000}, // 6
                                       {0b01111000, 0b00001000, 0b00001000, 0b00010000, 0b00010000, 0b00100000, 0b00100000, 0b00000000}, // 7
                                       {0b00110000, 0b01001000, 0b01001000, 0b00110000, 0b01001000, 0b01001000, 0b00110000, 0b00000000}, // 8
                                       {0b00110000, 0b01001000, 0b01001000, 0b00111000, 0b00001000, 0b01001000, 0b00110000, 0b00000000}, // 9
                                       {0b00000000, 0b00000000, 0b00010000, 0b00000000, 0b00000000, 0b00010000, 0b00000000, 0b00000000}, // :
                                       {0b00000000, 0b00000000, 0b00010000, 0b00000000, 0b00000000, 0b00010000, 0b00010000, 0b00100000}, // ;
                                       {0b00001000, 0b00010000, 0b00100000, 0b01000000, 0b00100000, 0b00010000, 0b00001000, 0b00000000}, // <
                                       {0b00000000, 0b00000000, 0b01111100, 0b00000000, 0b01111100, 0b00000000, 0b00000000, 0b00000000}, // =
                                       {0b00100000, 0b00010000, 0b00001000, 0b00000100, 0b00001000, 0b00010000, 0b00100000, 0b00000000}, // >
                                       {0b00111000, 0b01000100, 0b00000100, 0b00001000, 0b00010000, 0b00000000, 0b00010000, 0b00000000}, // ?
                                       {0b00111000, 0b01000100, 0b01011100, 0b01010100, 0b01011100, 0b01000000, 0b00111000, 0b00000000}, // @
                                       {0b00111000, 0b01000100, 0b01000100, 0b01111100, 0b01000100, 0b01000100, 0b01000100, 0b00000000}, // A
                                       {0b01111000, 0b01000100, 0b01000100, 0b01111000, 0b01000100, 0b01000100, 0b01111000, 0b00000000}, // B
                                       {0b00111000, 0b01000100, 0b01000000, 0b01000000, 0b01000000, 0b01000100, 0b00111000, 0b00000000}, // C
                                       {0b01111000, 0b01000100, 0b01000100, 0b01000100, 0b01000100, 0b01000100, 0b01111000, 0b00000000}, // D
                                       {0b01111100, 0b01000000, 0b01000000, 0b01111000, 0b01000000, 0b01000000, 0b01111100, 0b00000000}, // E
                                       {0b01111100, 0b01000000, 0b01000000, 0b01111000, 0b01000000, 0b01000000, 0b01000000, 0b00000000}, // F
                                       {0b00111000, 0b01000100, 0b01000000, 0b01011100, 0b01000100, 0b01000100, 0b00111000, 0b00000000}, // G
                                       {0b01000100, 0b01000100, 0b01000100, 0b01111100, 0b01000100, 0b01000100, 0b01000100, 0b00000000}, // H
                                       {0b01111100, 0b00010000, 0b00010000, 0b00010000, 0b00010000, 0b00010000, 0b01111100, 0b00000000}, // I
                                       {0b01111100, 0b00001000, 0b00001000, 0b00001000, 0b00001000, 0b01001000, 0b00110000, 0b00000000}, // J
                                       {0b01000100, 0b01001000, 0b01010000, 0b01100000, 0b01010000, 0b01001000, 0b01000100, 0b00000000}, // K
                                       {0b01000000, 0b01000000, 0b01000000, 0b01000000, 0b01000000, 0b01000000, 0b01111100, 0b00000000}, // L
                                       {0b01000100, 0b01101100, 0b01010100, 0b01000100, 0b01000100, 0b01000100, 0b01000100, 0b00000000}, // M
                                       {0b01000100, 0b01100100, 0b01100100, 0b01010100, 0b01001100, 0b01001100, 0b01000100, 0b00000000}, // N
                                       {0b00111000, 0b01000100, 0b01000100, 0b01000100, 0b01000100, 0b01000100, 0b00111000, 0b00000000} // O
                                       
                                       };

//comparison columns for lighting the grid
const unsigned char lightOn[] = {0b10000000, 0b01000000, 0b00100000, 0b00010000, 0b00001000, 0b00000100, 0b00000010, 0b00000001};

const int characterOffset = 32;
const int ledCount = 8;

void Display (const unsigned char first[], const unsigned char second[])
{
    int shift;
    int row;
    int column;
    unsigned char firstLetter;
    unsigned char secondLetter;
    
    for(shift = 0; shift < ledCount; shift++)
    {
        system("cls");
        
        printf("/========\\\n");

        for(row = 0; row < ledCount; row++)
        {
            printf("|");
            
            for(column = 0; column < ledCount; column++)
            {
                firstLetter = first[row] << shift;

                secondLetter = second[row] >> (ledCount - shift);
                
                if(firstLetter & lightOn[column] || secondLetter & lightOn[column])
                {
                    printf("0");
                }
                else
                {
                    printf(" ");
                }
            }
                        
            printf("|\n");
        }
        
        printf("\\========/");
        Sleep(100);
    }
}

int main (void)
{   
    int i;
    int length = (sizeof(characters) / sizeof(characters[0])) - 1;
    
    printf("Starting Byte Array Test\n\n");
    
    for(i = 0; i < length; i++)
    {
        Display(characters[i], characters[i + 1]);
    }
           
    printf("\n\nProgram Complete\n");
    
    return 0;
}