1. Is this a positive or a negative number?
0101 0001 0111 1100 is the binary representation of a positive integer, on 16 bits (2 Bytes).
In a signed binary in one's complement representation, the first bit (the leftmost) indicates the sign, 1 = negative, 0 = positive.
2. Get the binary representation of the positive (unsigned) number.
* Run this step only if the number is negative *
Flip all the bits of the signed binary in one's complement representation (reverse the digits) - replace the bits set on 1 with 0s and the bits on 0 with 1s:
* Not the case - the number is positive *
3. Map the unsigned binary number's digits versus the corresponding powers of 2 that their place value represent:
215
0 214
1 213
0 212
1 211
0 210
0 29
0 28
1 27
0 26
1 25
1 24
1 23
1 22
1 21
0 20
0
4. Multiply each bit by its corresponding power of 2 and add all the terms up.
0101 0001 0111 1100(2) =
(0 × 215 + 1 × 214 + 0 × 213 + 1 × 212 + 0 × 211 + 0 × 210 + 0 × 29 + 1 × 28 + 0 × 27 + 1 × 26 + 1 × 25 + 1 × 24 + 1 × 23 + 1 × 22 + 0 × 21 + 0 × 20)(10) =
(0 + 16 384 + 0 + 4 096 + 0 + 0 + 0 + 256 + 0 + 64 + 32 + 16 + 8 + 4 + 0 + 0)(10) =
(16 384 + 4 096 + 256 + 64 + 32 + 16 + 8 + 4)(10) =
20 860(10)
5. If needed, adjust the sign of the integer number by the first digit (leftmost) of the signed binary:
0101 0001 0111 1100(2) = 20 860(10)
The signed binary number in one's complement representation 0101 0001 0111 1100(2) converted and written as an integer in decimal system (base ten):
0101 0001 0111 1100(2) = 20 860(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.