From fixed-point binary

The binary point is between bits 4 and 5.

Convert fixed-point binary to denary:

Enter decimal number (e.g. 12.5)

The binary point is between bits 4 and 5. Add up the place values for each bit that is set to 1:

Place values: 8  4  2  1 . 0.5  0.25  0.125  0.0625

Example: Convert 01101100 to denary

Place values: 8  4  2  1 . 0.5  0.25  0.125  0.0625
Binary:       0  1  1  0 . 1    1     0      0

Add the 1s: 4 + 2 + 0.5 + 0.25 = 6.75

In fixed-point binary representation, the binary point is at a fixed position. In this case, it's between bits 4 and 5, meaning:

  • Bits 7-4 represent the whole number part (place values: 8, 4, 2, 1)
  • Bits 3-0 represent the fractional part (place values: 0.5, 0.25, 0.125, 0.0625)

To convert from fixed-point binary to denary:

  1. Identify which bits are set to 1
  2. Add up the corresponding place values
  3. The result is your denary answer

References:

  • Wikibooks Computer Science A level (fixed-point): AQA