ADSP-BF535 Blackfin Processor Hardware Reference
2-45
Computational Units
The arithmetic shift and logical shift operations can be further broken
into subsections. Instructions that are intended to operate on 16-bit single
or paired numeric values, as would occur in many DSP algorithms, can
use the instructions
ASHIFT
and
LSHIFT
. These are typically three operand
instructions.
Instructions that are intended to operate on a 32-bit register value and use
two operands, such as instructions frequently used by a compiler, can use
the
>>>
and
>>
instructions.
Arithmetic shift, logical shift, and rotate instructions can obtain the shift
argument from a register or directly from an immediate value in the
instruction. For details about shifter-related instructions, see
“Shifter
Instruction Summary” on page 2-48
.
Two Operand Shifts
Two operand shift instructions shift an input register and deposit the
result in the same register.
Immediate Shifts
An immediate shift instruction shifts the input bit pattern to the right
(down-shift) or left (up-shift) by a given number of bits. Immediate shift
instructions use the data value in the instruction itself to control the
amount and direction of the shifting operation.
The following example shows the input value down-shifted.
R0 = 0x0000 B6A3 ;
R0 >>= 0x04 ;
results in
R0.H = 0x0000 ;
R0.L = 0xB6A3 ;
Содержание ADSP-BF535 Blackfin
Страница 80: ...Development Tools 1 26 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 312: ...Working With Memory 6 86 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 332: ...System Interfaces 7 20 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 360: ...Dynamic Power Management Controller 8 28 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 446: ...Beginning and Ending an SPI Transfer 10 40 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 522: ...Timing Examples 11 76 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 562: ...IrDA Support 12 40 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 608: ...PCI I O Issues 13 46 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 672: ...References 14 64 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 810: ...SDRAM Controller SDC 18 86 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 811: ...ADSP BF535 Blackfin Processor Hardware Reference 18 87 External Bus Interface Unit...
Страница 812: ...SDRAM Controller SDC 18 88 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 860: ...DMA Bus Debug Registers 20 30 ADSP BF535 Blackfin Processor Hardware Reference...
Страница 908: ...SDRAM Controller External Bus Interface Unit B 36 ADSP BF535 Blackfin Processor Hardware Reference...