Question about ASCII conversion.

[maniac84]

Hi there. Is there a way in C coding to convert like the way like this? For example I got '1' equals to 0x31, and '2' equals to 0x32. I want to convert 0x31, 0x32 to 0x12.

 

[kam1787]

not sure I follow the sequence; 0x31, 0x32 ...to 0x12. It increases and then decreases? can you explain the last term?

if there is no sequence or logic then use a switch statement

 

[paulfjujo]

hello,

unsigned char c1,c2;
unsigned char R;
c1='1' -'0';
c2='2'-'0';
R=c1<<4 + c2;    // 0x12

or Maybe you want to get "12" ?

char Texte[16];// table of char
char *txt;  // pointer
.......
txt=&Texte[0]; // initialise pointer
*txt=c1;
*txt+1=c2;
*txt+2=0; // end of string
// now txt point on the result '12'

 

[Gorgon]

Do you want to convert the Ascii numbers to BCD arithmetic or hexadecimal?
'12' in ascii is not equeal to 0x12 in hex, the correct value here is 0x0C.

The value 0x12 is in BCD, where each nibble(4bits) in the byte is one digit from 0-9.
BCD=Binary Coded Decimal.

 

[maniac84]

hello,

unsigned char c1,c2;
unsigned char R;
c1='1' -'0';
c2='2'-'0';
R=c1<<4 + c2;    // 0x12

or Maybe you want to get "12" ?

char Texte[16];// table of char
char *txt;  // pointer
.......
txt=&Texte[0]; // initialise pointer
*txt=c1;
*txt+1=c2;
*txt+2=0; // end of string
// now txt point on the result '12'

Your first coding is the answer I want. Thanks!