Declaration; Function Use - Freescale Semiconductor DSP56800E User Manual

• Fractional output with mixed inputs - the output is the fractional portion of the result;
the result is within the range <-1 ; 1). The inputs are the accumulator and fractional
values. The result may saturate.
• Accumulator output - the output is the accumulator type where the result can be out
of the range <-1 ; 1). The result may overflow.
The available versions of the
table:
Function name
MLIB_MulRndSat_F16
MLIB_MulRndSat_F16as
MLIB_MulRndSat_F32ls
MLIB_MulRndSat_F32
MLIB_MulRndSat_A32

2.34.2 Declaration

The available MLIB_MulRndSat
frac16_t MLIB_MulRndSat_F16(frac16_t
frac16_t MLIB_MulRndSat_F16as(acc32_t
frac32_t MLIB_MulRndSat_F32ls(frac32_t
frac32_t MLIB_MulRndSat_F32(frac32_t
acc32_t MLIB_MulRndSat_A32(acc32_t

2.34.3 Function use

The use of the MLIB_MulRndSat
Freescale Semiconductor, Inc.
MLIB_MulRndSat
Table 2-34. Function versions
Input type Result
type
Mult. 1 Mult. 2
frac16_t frac16_t frac16_t
acc32_t frac16_t frac16_t
frac32_t frac16_t frac32_t
frac32_t frac32_t frac32_t
acc32_t acc32_t acc32_t
functions have the following declarations:
f16Mult1,
a32Accum,
f32Mult1,
f32Mult1,
a32Mult1,
function is shown in the following example:
MLIB User's Guide, Rev. 2, 10/2015
function are shown in the following
Product of two 16-bit fractional multiplicands; the output is
rounded to the upper 16 bits of the results [16..31]. The
output is within the range <-1 ; 1).
Product of a 32-bit accumulator and a 16-bit fractional
multiplicand; the output is a 16-bit fractional value, which is
rounded to the upper 16 bits of the fractional portion of the
result [16..31]. The output is within the range <-1 ; 1).
Product of a 32-bit multiplicand and a 16-bit fractional
multiplicand; the output is rounded to the upper 32 bits of
the fractional portion of the result [16..47]. The output is
within the range <-1 ; 1).
Product of two 32-bit fractional multiplicands; the output is
rounded to the upper 32 bits of the results [16..31]. The
output is within the range <-1 ; 1).
Product of two 32-bit accumulator multiplicands; the output
is rounded to the the mid bits of the result [16..47]. The
output is within the range <-65536.0 ; 65536.0).
frac16_t f16Mult2)
frac16_t f16Mult)
frac16_t f16Mult2)
frac32_t f32Mult2)
acc32_t a32Mult1)
Chapter 2 Algorithms in detail
Description
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