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This source code below converts a text file with binaries into a text file with hexadecimals. Imagine we have a file of binaries called "hello.bin", we are going to convert it into hexadecimals and write it into a file called "hello.com".

hello.bin

[code]
10110100 00001001
10111010 00001001 00000001
11001101 00100001
11001101 00100000
01101000 01100101 01101100 01101100 01101111 00100100
[/code]

Concept (in terms of ASM)

[code]
mov ah,09
mov dx,0109
int 21
int 20
db "hello$"
[/code]

hello.com

[code]
B4 09 BA 09 01 CD 21 CD 20 68 65 6C 6C 6F 24
[/code]

where you can see how the binaries, hexadecimals and ASM are linked.

[code]
10110100 = B4 = mov ah
00001001 = 09 = 09
[/code]

What "hello.com" does when ran is it prints the word "hello" and exits. Generally this code is a converter but it has given me a further insight of what assembly would look like and how the machine language works now. The source code is as below and it is done in C language (but you would need to write the filename as .cpp instead of .c since the program was not programmed according the C proper structure whereby it should be defining variables before statements).

Source code

[code]
#include <stdio.h>
#include <stdlib.h>

void help(char* fname) {
printf(
"Code programs in binary - by Jakash3\n"
"Usage: %s outfile infile"
"Notes:\n"
" infile = Text file containing ascii 1's and 0's.\n"
" 8 bits per byte, all other characters\n"
" and whitespace ignored.\n"
" outfile = Name of program to create and write to.\n",
fname
);
exit(1);
}

int main(int argc, char** argv) {
if (argc!=3) help(argv[0]);
FILE *dst, *src;
dst = fopen(argv[1],"wb");
if (!dst) { printf("Could not create or truncate %s\nQuitting...",argv[1]); return 1;}
src = fopen(argv[2],"r");
if (!src) { printf("Could not open %s\nQuitting...",argv[2]); return 1;}
char c, byte=0;
int i=0, count=0;
while (!feof(src)) {
if (i==8) { fwrite(&byte,1,1,dst); byte=0; i=0; count++; }
fread(&c,1,1,src);
switch (c) {
case '1':
byte |= ((c=='1') << (7-i));
case '0':
i++;
}
}
fclose(src);
if (!fclose(dst))
printf("Wrote %d bytes to %s\n",count,argv[1]);
return 0;
}
[/code]

Download binary (.exe).

This code was written by jakash3 from Leetcoders.org
* Original link here.