binary char array representation to hex ? ( what's wrong with this C code )

[Pigi_102]

Hi all,
I have an arduino sketch code that works well and I'm convertin in c ansi but I'm having a (some) problem.

My input data is a char array like this:

pkt="10100000"

in arduino c I have this code:

int ret

 for (i = 0; i <  8; i++) {
    ret = (ret << 1) ^ ((pkt[i] & B00010000) ? 1 : 0);
 }

and the ret value, out of the loop is 160 ( which is correct ).

I have "translated" in:

 for (i = 0; i <  8; i++) {
    ret = (ret << 1) ^ ((pkt[i] & 0b00010000) ? 1 : 0);
 }

but ret value is 255, which obviously is wrong.

What I'm doing wrong ?

Thanks in advance

Pierluigi

 

[xenos]

Your code is completely wrong.
you binary AND an ascii val (48 or 49 if I remember correctly) with one bit in pos 5 (val is 16 and that produces TRUE for both zero or one ascii vslues). Xor is also questionable in this position.

- - - Updated - - -

Have a look at my code in:
https://www.edaboard.com/threads/340997/#post1454632

 

[Pigi_102]

xenos,
your code work.
Still can't understand the error in my code, but for the moment I'm fine with that.


Pihi

 

[xenos]

...

pkt[i] & B00010000

...

pkt has eigther 48 or 49 (ie eighter b0110000 or b0110001)
what should the (b00010000 & b0110000) produce as output?
what should the (b00010001 & b0110000) produce as output?

I do not see how this code should work in arduino.

Try replacing the b00010000 in your code with b00000001 (or just 1 ;-))