Format

1.15 format 16-bit number, bit 15 ( left-most bit ) is sign-bit, binary point is between bit 15 and bit 14 (i.e. m = 15 ) X = S . x x x x x x x x x x x x x x x Resolution = 2 -15 V(X) min = -1    ( 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 )    ( 8000 Hex ) V(X) max = 1 - 2 -15    (0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 )    ( 7FFF Hex ) To convert a negative decimal number, say -0.242146, to 1.15 format: Multiply the positive, ie. 0.242146 by 2^15 and convert to HEX, which gives you 1EFE. Take the two's compliment of the number, which will give you correct value in 1.15 format, i.e. 0xE101 in this example.
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