
ADSP-2126x SHARC Processor Hardware Reference
2-51
Processing Elements
In SISD mode (
PEYEN
bit=0), the register-to-register transfers are unidirec-
tional, meaning that an operation performed on one processing element is
not duplicated on the other processing element. The SISD transfer uses a
source register and a destination register. Either register can be in either
element’s data register file. For a summary of unidirectional transfers, see
the upper half of
. Note that in SISD mode a
condition for an instruction only tests in the PEx element but it applies to
the entire instruction.
In SIMD mode (
PEYEN
bit=1), the register-to-register transfers are bidirec-
tional, meaning that an operation performed on one element is duplicated
in parallel on the other element. The instruction uses two source registers
(one from each element’s register file) and two destination registers (one
from each element’s register file). For a summary of bidirectional trans-
fers, see the lower half of
. Note that in SIMD mode
conditional explicit and implicit transfers are tested and executed sepa-
rately in PEx and PEy, respectively, as detailed in
Bidirectional register-to-register transfers in SIMD mode are allowed
between a data register and DAG, control, or status registers. When the
DAG, control, or status register is a source of the transfer, the destination
can be a data register. This SIMD transfer duplicates the contents of the
source register in a data register in both processing elements.
Careful programming is required when a DAG, control, or status
register is a destination of a transfer from a data register. If the des-
tination register has a complement (for example
ASTATx
and
ASTATy
), the SIMD transfer moves the contents of the explicit data
register into the explicit destination and moves the contents of the
implicit data register into the implicit destination (the comple-
ment). If the destination register has no complement (for example,
I0), only the explicit transfer occurs.
Summary of Contents for ADSP-21261 SHARC
Page 30: ...Contents xxx ADSP 2126x SHARC Processor Hardware Reference ...
Page 40: ...Register Diagram Conventions xl ADSP 2126x SHARC Processor Hardware Reference ...
Page 58: ...Differences From Previous SHARCs 1 18 ADSP 2126x SHARC Processor Hardware Reference ...
Page 112: ...Secondary Processing Element PEy 2 54 ADSP 2126x SHARC Processor Hardware Reference ...
Page 178: ...Summary 3 66 ADSP 2126x SHARC Processor Hardware Reference ...
Page 204: ...DAG Instruction Summary 4 26 ADSP 2126x SHARC Processor Hardware Reference ...
Page 322: ...Setting Up DMA 7 32 ADSP 2126x SHARC Processor Hardware Reference ...
Page 436: ...SPORT Programming Examples 9 86 ADSP 2126x SHARC Processor Hardware Reference ...
Page 521: ...ADSP 2126x SHARC Processor Hardware Reference 11 31 Input Data Port rts IDP_ISR end ...
Page 522: ...Input Data Port Programming Example 11 32 ADSP 2126x SHARC Processor Hardware Reference ...
Page 590: ...Timer Programming Examples 14 20 ADSP 2126x SHARC Processor Hardware Reference ...
Page 796: ...I O Processor Registers A 174 ADSP 2126x SHARC Processor Hardware Reference ...
Page 800: ...B 4 ADSP 2126x SHARC Processor Core Manual ...
Page 846: ...Index I 36 ADSP 2126x SHARC Processor Hardware Reference ...