Re: [Mspgcc-users] bit reverse byte fn()

[Steve Underwood]

Hi,

Gosh, I haven't seen that one for years. I think it needs a barrel 
shifter to work well, though. I'm pretty sure direct shift out and shift 
in will do better on the MSP430.

Regards,
Steve


Regards,
Steve


Leon Heller wrote:

Here's a clever way to do it that I found via Google:

//
// Reverse the order of bits within a byte.
// Returns: The reversed byte value.
//
BYTE ReverseBits(BYTE b)
{
 BYTE c;
 c  = ((b >>  1) & 0x55) | ((b <<  1) & 0xaa);
 c |= ((b >>  2) & 0x33) | ((b <<  2) & 0xcc);
 c |= ((b >>  4) & 0x0f) | ((b <<  4) & 0xf0);
   return(c);
}

I haven't checked it, though.