ADSP-2126x SHARC Processor Hardware Reference
2-7
Processing Elements
Short Word Floating-Point Format
The DSP supports a 16-bit floating-point data type and provides conver-
sion instructions for it. The short float data format has an 11-bit mantissa
with a 4-bit exponent plus sign bit, as shown in
. The 16-bit
floating-point numbers reside in the lower 16 bits of the 32-bit float-
ing-point field.
Packing for Floating-Point Data
Two shifter instructions,
FPACK
and
FUNPACK
, perform the packing and
unpacking conversions between 32-bit floating-point words and 16-bit
floating-point words. The
FPACK
instruction converts a 32-bit IEEE float-
ing-point number to a 16-bit floating-point number. The
FUNPACK
instruction converts the 16-bit floating-point numbers back to 32-bit
IEEE floating-point numbers. Each instruction executes in a single cycle.
The results of the
FPACK
and
FUNPACK
operations appear in
and
.
Figure 2-4. 16-Bit Floating-Point Format
s
e0
15
14
11
10
0
1 . f10
f0
e3
• • •
• • •
HIDDEN BIT
BINARY POINT
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 ...