ARM Compiler toolchain v4.1 for µVision Using the Compiler

Compiler Coding Practices
5.47 Half-precision floating-point number format
The half-precision floating-point formats available are ieee and alternative. In both formats,
the basic layout of the 16-bit number is the same. See Figure 5-1.
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
S E T
Where:
Figure 5-1 Half-precision floating-point format
S (bit[15]):
E (bits[14:10]):
T (bits[9:0]):
Sign bit
Biased exponent
Mantissa.
The meanings of these fields depend on the format that is selected.
IEEE half-precision format is as follows:
IF E==31:
IF T==0: Value = Signed infinity
IF T!=0: Value = Nan
T[9] determines Quiet or Signalling:
0: Quiet NaN
1: Signalling NaN
IF 0