Embedded Software and Motor Control Libraries for PXR40xx

}
// output should be 0x5A820000 ~ FRAC32(0.70710678)
f32Out = GFLIB_Sqrt (f32In);
4.83 Function GFLIB_Sqrt_F16
This function returns the square root of input value.
4.83.1 Declaration
tFrac16 GFLIB_Sqrt_F16(tFrac16 f16In);
4.83.2 Arguments
Table 4-105. GFLIB_Sqrt_F16 arguments
Type Name Direction Description
tFrac16 f16In input The input value.
4.83.3 Return
The function returns the square root of the input value. The return value is within the [0,
1) fraction range.
4.83.4 Description
The GFLIB_Sqrt_F16 function computes the square root of the input value.
Chapter 4 API References
The computations are made by a simple iterative testing of each bit starting from the most
significant one. In total, 15 iterations are made, each performing the following steps:
1. Add to the tentative square root value a single testing bit.
2. Square the tentative square root value and test whether it is greater or lower than the
input value.
3. If greater, then clear the bit in the tentative square root value.
4. Shift the single testing bit right
Embedded Software and Motor Control Libraries for PXR40xx, Rev. 1.0
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