Thread: help with c program: binary to ascii program

This is a program where i input a 8 digit binary character and it calculates binary to ascii so if i enter a binary character 01000001 the program calculate and give me the ascii 65 (which is a 'A')

My problem is, once i get 8 character i want to calculate the 8 and get the ascii then calculate the next set. Right now it calculate the last set i input.

ie. i enter 1010101011110000, itll do the calculations for 11110000 and not the first part which is 10101010

would i have to add code into the if statement?

Code:

int bit_to_ascii(const char core[ ], char data[ ]);

int main( ) {
   char core2[256];
   char data2[13];
   int rc2;
   printf("enter: ");
   scanf("%256[^\n]", core2);
   rc2 = bit_to_ascii(core2, data2);
   printf("%d", rc2);
   return 0;
}

int bit_to_ascii(const char core[ ], char data[ ]) {
   int i, rc = 0, j, inte[7];
   char binarray[9];
   for(i=0, j=0; core[i] != '\0'; i++) {
     switch(core[i]) {
	 case '1':
	 case '0':
  	  if(j<8) {
	       binarray[j++] = core[i];
	    }
	    else {
               j = 0; /* resets j to 0 after 8 1's or 0's have been found */
          if(j<8) {
	       binarray[j++] = core[i]; 
	    }
    }
	    break;
      }
   }
   binarray[j] = '\0';
   inte[0] = (binarray[0] - 48) * 128;
   inte[1] = (binarray[1] - 48) * 64;
   inte[2] = (binarray[2] - 48) * 32;
   inte[3] = (binarray[3] - 48) * 16;
   inte[4] = (binarray[4] - 48) * 8;
   inte[5] = (binarray[5] - 48) * 4;
   inte[6] = (binarray[6] - 48) * 2;
   inte[7] = (binarray[7] - 48) * 1;
   
   printf("the binary array is: '%s' %d %d %d\n", binarray, inte[0], inte[1], inte[2]);
   return rc;
}

Well, when you reset j to 0, you then go ahead and write over the eight bits you had just read in. So at the end of the day, you've only got the last eight bits in your array. At that point, you should maybe stop reading and write out an answer, or store an answer, or do something with the data before reading more in.

oh what a simple mistake thanks alot man i got it working now

i have a next one though, i forgot to mention but if the last set is less than 8 characters i need to add 0's to make it a full 8 characters

so if the last set is: 10101

then i need to add 3 0's so it'll be 10101000

this is what i tried. i got the lenght of the binarray string, and the subtract the lenght by 8 (lenght is 6, do 8 - 6 equals 2 that means i add 2 zero's) but i can't get it working

Code:

   len = strlen(binarray);
   printf("%d", len);
   if(len<8){
             len2 = 8-5;
             printf("%d", len);
             }

Before or after you set binarray[j]='\0'?

right now its like this (after binarray = /0)

Code:

binarray[j] = '\0';
   len = strlen(binarray);
   printf("%d\n", len);
                if(len<8){
                          len2 = 8 - len;
                          printf("%d\n", len2);
                          for(m=len2; m<9; m++){
                                      binarray[len2]=0;
                                      }
                          }
   inte[0] = (binarray[0] - 48) * 128;
   inte[1] = (binarray[1] - 48) * 64;
   inte[2] = (binarray[2] - 48) * 32;
   inte[3] = (binarray[3] - 48) * 16;
   inte[4] = (binarray[4] - 48) * 8;
   inte[5] = (binarray[5] - 48) * 4;
   inte[6] = (binarray[6] - 48) * 2;
   inte[7] = (binarray[7] - 48) * 1;

Why not try

Code:

binarray[len2] = '0';

with single quotes like ' it does the same thing like before, with double quote it says this "61 D:\Untitled1.cpp invalid conversion from `const char*' to `char' "

also i made a mistake it should say

Code:

binarray[m] = '0';

not len2 where it says m

Well, you want the single quotes. So now we're back to "not working". Does len print what you think it should? And I don't think you have your loop correct; if you've read in 6 characters, so that len is 6, then your for-loop will zero out from 2 to 8. You should just go from len to 7 with the '0's.

you are right again i got it working good now, ill show you what i did for the loop

Code:

binarray[j] = '\0';
   len = strlen(binarray);
   printf("%d\n", len);
                if(len<8){
                          len2 = 8 - len;
                          m = len;
                          printf("%d\n", len2);
                          /*for(m=len2; m<9; m++){*/
                          do {
                                      binarray[m]='0';
                                      m++;
                          }while (m != 8);            
                                      /*}*/
                          }

how is it now??

So you've got more cases to work with now, since there are more characters that you care about. I would put 'R' in the switch, and in that case look to see if the next two characters are T and P.

does it matter the placement, like if i put a case 'R': before the case 0: and 1:?

also, how should i check if the next two are TP? this is where im stuck.