ARM Compiler toolchain v4.1 for µVision Using the Compiler

Compiler Coding Practices
5.65 Hexadecimal floating-point numbers in C99
C99 supports floating-point numbers that can be written in hexadecimal format. For example:
float hex_floats(void)
{
return 0x1.fp3; // 1 15/16 * 2^3
}
In hexadecimal format the exponent is a decimal number that indicates the power of two by
which the significant part is multiplied. Therefore 0x1.fp3 = 1.9375 * 8 = 1.55e1.
C99 also adds %a and %A format for printf().
5.65.1 See also
Concepts
• New language features of C99 on page 5-77.
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