NS32FX161-15 Datasheet, PDF (51/102 Pages) National Semiconductor (TI) – Advanced Imaging/Communication Signal Processors

3 0 Functional Description (Continued)
Operation
aligned integer X Y
integer Z
for (n40 n ^k LENG n00)
Z 2n 4 (integer) (Z 2n 0 X n low *
Y n low)
Z 2n01 4 (integer) (Z 2n01 0 X n high
* Y n high)
Note When PARAM CLR is set to ‘‘1’’ only multiplication is done without
addition When PARAM SUB is set to ‘‘1’’ the ‘‘a’’ sign is replaced
by a ‘‘b’’ sign
VAIMADS Vector Aligned Integer Multiply and Add
Saturated
The VAIMADS instruction multiplies corresponding ele-
ments of the X and Y integer vectors and adds or subtracts
the result as an integer value to the integer vector Z This
result is placed in the Z output vector The saturation logic
provides clamping of the accumulator results before writing
the result back to the Z vector whenever the result cannot
be represented correctly within the limits of the integer data
type
Syntax
EXEC VAIMADS
15
10000
Operation
11 10
0
101 0101 1100
aligned integer X Y
integer Z
for (n40 n ^k LENG n00)
Z 2n 4 (integer) (Z 2n 0 X n low *
Y n low)
Z 2n01 4 (integer) (Z 2n01 0 X n high *
Y n high)
VRMAD Vector Real Multiply and Add
The VRMAD instruction multiplies corresponding elements
of the X and Y real vectors and adds or subtracts the result
to the real vector Z This result is placed in the Z output
vector
Syntax
EXEC VRMAD
15
11 10
0
10000
100 0011 0011
Operation
real X Y Z
for (n40 n ^k LENG n00)
Z n 4 (real) (Z n 0 X n * Y n )
Note When PARAM CLR is set to ‘‘1’’ only multiplication is performed
without addition When PARAM SUB is set to ‘‘1’’ the ‘‘a’’ sign is
replaced by a ‘‘b’’ sign
VARMAD Vector Aligned Real Multiply and Add
The VARMAD instruction multiplies corresponding elements
of the X and Y real vectors and adds or subtracts the result
to the real vector Z This result is placed in the Z output
vector
Syntax
EXEC VARMAD
15
10000
Operation
11 10
0
100 0000 1110
aligned real X Y Z
for (n40 n ^k LENG n00)
Z n low 4 (real) (Z n low 0 X n low *
Y n low)
Z n high 4 (real) (Z n high 0 X n high
* Y n high)
Note When PARAM CLR is set to ‘‘1’’ only multiplication is performed
without addition When PARAM SUB is set to ‘‘1’’ the ‘‘a’’ sign is
replaced by a ‘‘b’’ sign
VEMAD Vector Extended Multiply and Add
The VEMAD instruction multiplies corresponding elements
of the X and Y real vectors and adds or subtracts the result
as an extended-precision value to the extended-precision
vector Z This result is placed in the Z output vector
Syntax
EXEC VEMAD
15
11 10
0
10000
101 0001 0010
51