ADSP-2126x SHARC Processor Hardware Reference
2-25
Processing Elements
The
MRF
register is divided into
MRF2
,
MRF1
, and
MRF0
registers, which can
be individually read from or written to the register file. Each of these reg-
isters has the same format. When data is read from
MRF2
, it is
sign-extended to 32 bits as shown in
eight LSBs of the 40-bit register file location when data is read from
MRF2
,
MRF1
, or
MRF0
to the register file. When the DSP writes data into
MRF2
,
MRF1
, or
MRF0
from the 32 MSBs of a register file location, the eight LSBs
are ignored. Data written to
MRF1
is sign-extended to
MRF2
, repeating the
MSB of
MRF1
in the 16 bits of
MRF2
. Data written to
MRF0
is not
sign-extended.
Figure 2-8. Multiplier Fixed-Point Result Placement
Figure 2-9. MR Transfer Formats
MRF2
MRF0
OVERFLOW
UNDERFLOW
FRACTIONAL RESULT
OVERFLOW
INTEGER RESULT
OVERFLOW
MRF1
79
63
31
0
ZE ROS
S IGN-EXTEND
MRF2
MRF0
MRF1
16 BITS
16 BI TS
8 BITS
32 BI TS
ZEROS
ZEROS
8 BI TS
32 BITS
8 BITS
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 ...