Thread: How to read sequence of bits (0`s and 1`s) by Functional call in C language

Th

Thanks algorism. Through your program, i can generate random values like 0's and 1's.

I am very poor in programming side. Just start learning. Can you give pseudocode/algorithm for your code.

Thanks algorism . With the help of your program codes, i am able to generate Random bits like 0`s and 1's. I am very poor in programming sides, i am just start learning for my project work. Can you give pseudocode/algorithm for above program.

Originally Posted by SarasMuthu

Can you give pseudocode/algorithm for above program.

I'm not sure what you mean.

Also, beware that the given code always produces the same sequence of bits. To have it produce different sequences you would need to "seed" the lfsr with some arbitrary value each time you run the program. The simplest method is to use the current time. For hardcore uses there are much better ways to seed the generator, and of course the generator function itself would need to be tested for decent randomness.

Code:

#include <stdio.h>
#include <time.h>

static unsigned lfsr = 0x5;

int PRBS_prj() {
  int bit = ((lfsr >> 0) ^ (lfsr >> 2) ^ (lfsr >> 3) ^ (lfsr >> 4) ) & 1;
  lfsr = (lfsr >> 1) | (bit << 7);
  return bit;
} 
 
int main()  {
  lfsr = (unsigned)time(NULL);
  for (int i = 0; i < 100; i++)
    printf("%d", PRBS_prj());
  putchar('\n');  
  return 0;
}

Originally Posted by algorism

I know exactly what he's talking about. The point is that it has nothing to do with SarasMuthu's question and can only confuse the issue. In that sense it is incoherent (to the OP) and misses the point entirely.

"missing the point" is entirely different from " ignore"
think OUT of the BOX you just programmed your self in.
i tried to explain that there is NO real random in any computer OS.
so, the USER comes in at that point... the only NON digital influence within the system, i supose.
GReaper mentions that many influences exist. very well indeed, good point.
maybe a XOR over some databus input will give a resonable "real random".

programs are made for users, right ?