设置二进制数等于设置掩码的其他二进制数

Question

I have the following three values:

PORTB  = 00011011
Mask   = 00000111
Value  = 00100110

With these values I am trying to set PORTB equal to Value where the Mask is set to one. The output would be the following:

Output = 00011110

As you can see I am not messing with the first 5 bits of PORTB. The last three bits though I am setting. Of course this wouldn't be the case if the Mask and Value were even more complex. There doesn't seem to be an operator that can help me solve this equation, I did try the following:

Mask    = 00000111
Value   = 00100110
------------------ AND
PORTB   = 00011011
Output1 = 00000110
------------------ ??? This is where I get stuck, my first step doesn't seem to help much...
Output2 = 00011110

I hope someone can help me out as I can't find any solution/answer online which can help me.

Answer 1

If i understood it correctly, this should be what you're looking for

PORTB = (PORTB & ~Mask) | (Value & Mask);

Here's what it does

PORTB   = 00011011
~Mask   = 11111000 
------------------ AND
Output1 = 00011000

Value   = 00100110 
Mask    = 00000111 
------------------ AND
Output2 = 00000110


Output1 = 00011000
Output2 = 00000110
------------------ OR
Output  = 00011110