ADSP-BF53x/BF56x Blackfin Processor Programming Reference
12-11
Logical Operations
The Type I
LFSR
s (no feedback) applies a 32-bit registered mask to a
40-bit state residing in Accumulator
A0
, followed by a bit-wise XOR
reduction operation. The result is placed in CC and a destination register
half.
The Type I
LFSR
s (with feedback) applies a 40-bit mask in Accumulator
A1
to a 40-bit state residing in
A0
. The result is shifted into
A0
.
In the following circuits describing the BXOR instruction group, a
bit-wise XOR reduction is defined as:
where B
0
through B
N–1
represent the N bits that result from masking the
contents of Accumulator
A0
with the polynomial stored in either
A1
or a
32-bit register. The instruction descriptions are shown in
Figure 12-1
.
In the figure above, the bits
A0
bit 0 and
A0
bit 1 are logically AND’ed
with bits D[0] and D[1]. The result from this operation is XOR reduced
according to the following formula.
Figure 12-1. Bit-Wise Exclusive-OR Reduction
Out
B
(
(
(
(
(
0
B
1
)
B
2
)
B
3
)
...
⊕ )
B
n
1
–
)
⊕
⊕
⊕
⊕
=
D[0]
D[1]
A0[0]
A0[1]
s(D)
s D
( )
A0 0
[ ]
&
D 0
[ ] )
A0 1
[ ]
&
D 1
[ ]
(
⊕
(
)
=
Содержание ADSP-BF53x Blackfin
Страница 38: ...Conventions xxxviii ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 134: ...System Reset and Powerup 3 18 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 324: ...Instruction Overview 7 20 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 486: ...Instruction Overview 13 28 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 512: ...Instruction Overview 14 26 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 604: ...Instruction Overview 15 92 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 688: ...Instruction Overview 18 48 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 742: ...Instruction Overview 19 54 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 752: ...Examples 20 10 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 780: ...Product Identification Register 21 28 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 790: ...ADSP BF535 Flags A 10 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 800: ...Performance Monitor Registers B 10 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 994: ...Instructions Listed By Operation Code C 194 ADSP BF53x BF56x Blackfin Processor Programming Reference...
Страница 1042: ...Index I 40 ADSP BF53x BF56x Blackfin Processor Programming Reference...