bit manipulation in c

DeepikaNS's Avatar, Join Date: Apr 2010
Newbie Member
Hi

we have a buffer say char array.[1].so the size will be 1 byte.
Now our problem is say we have 8 bits data say 10110101.
now this must be assigned to array[0] variable as 1 byte.
bit manipulation is not happening.kindly help us in this regard
If possible post us a sample code for the same

here we are posting sample code for the same


  1. decleration:
  2. struct aaa {
  3. unsigned char buff1:1;
  4. unsigned char buff2:1;
  5. unsigned char buff3:1;
  6. unsigned char buff4:1;
  7. unsigned char buff5:1;
  8. unsigned char buff6:1;
  9. unsigned char buff7:1;
  10. unsigned char buff8:1;
  11. }complete_buff;
  12. complete_buff->buf1=(unsigned char)0x01;;
  13. complete_buff->buf2=(unsigned char)0X00;
  14. complete_buff->buff3=(unsigned char)0x01;
  15. complete_buff->buff4=(unsigned char)0x01;
  16. complete_buff->buff5=(unsigned char)0x00;
  17. complete_buff->buff6=(unsigned char)0x00;
  18. complete_buff->buff7=(unsigned char)0x00;
  19. complete_buff->buff8=(unsigned char)0x00;
  20. char array[0]=(complete_buff->buff1>>7)| (complete_buff->buff2>>6)|(complete_buff->buff3>>5)|(complete_buff->buff4>>4)|(complete_buff->buff5>>3)|(complete_buff->buff6>>2)|(complete_buff->buff7>>1)|(complete_buff->buff8)
virxen's Avatar, Join Date: Nov 2009
Pro contributor
convert bits into dec value and then store the ascii character of this value into your array
(for example 00110001(bin)-->49(dec)--->'1'(ascii char) )

Code:
..........
    char a=49;
    printf("\n a=%c",a);
..............
check here for code related to convert bin to dec
http://www.daniweb.com/code/snippet216372.html#

Last edited by virxen; 20Apr2010 at 17:51..
xpi0t0s's Avatar, Join Date: Aug 2004
Mentor
The posted code (by the OP) doesn't work because you're shifting the wrong way. If you shift 00000001 right by any number of bits this will become zero. To get 10000000 from 00000001 you need to shift it LEFT by 7 bits (operator <<), not right (>>).