Question

Q7

. Perform the following operations using bit masking.

(a)

Set the bits 2, 4 and 6 of the register P1OUT simultaneously

(b)

Clear the bits 2, 4 and 6 of the register P1OUT simultaneously

(c)

Toggle the bits 2, 4 and 6 of the register P1OUT simultaneously

(d)

Toggle all the bits of P1OUT simultaneously except the bits 2, 4 and 6

Answer 1

a.Setting a bit in kth position means making the bit in the kth position to 1 whether it is 0 or 1.

If P1OUT=11100011(i.e 227), then setting 2,4,6 bits makes it to 11101011 i.e 235

b.clearing a bit in kth popsition means making the bit in kth position to 0 whether it is 0 or 1.

If P1OUT = 11100011(i.e 227) then clearing 2,4,6 bits makes it to 11000001 i.e 193

c.Toggling a bit in kth position means making the bit in kth position to 0 if it is 1 and vice-versa.

if P1OUT = 11100011(i.e 227) toggling 2,4,6 bits makes it to 11001001 i.e 201

d.If P1OUT = 11100011(i.e 227) then toggling all bits except 2,4,6 bits means toggling 1,3,5,7,8 bits makes it to 01110110 i.e 118