ADSP-2126x SHARC Processor Hardware Reference
4-7
Data Address Generators
Bits in the
MODE1
register can activate alternate register sets within the
DAGs: the lower half of DAG1 (
I
,
M
,
L
,
B0–3
), the upper half of DAG1
(
I
,
M
,
L
,
B4–7
), the lower half of DAG2 (
I
,
M
,
L
,
B8–11
), and the upper half
of DAG2 (
I
,
M
,
L
,
B12–15
shows the DAGs’ primary and alter-
nate register sets.
To share data between contexts, a program places the data to be shared in
one half of either the current DAGs’ registers or the other DAG’s registers
and activates the alternate register set of the other half. The following
example demonstrates how code handles the maximum one cycle of
latency from the instruction that sets the bit in
MODE1
to when the
Figure 4-2. Data Address Generator Primary and Alternate Registers
I0
I1
I2
I3
M0
M1
M2
M3
L0
L1
L2
L3
B0
B1
B2
B3
SRD1L
I4
I5
I6
I7
M4
M5
M6
M7
L4
L5
L6
L7
B4
B5
B6
B7
SRD1H
I8
I9
I10
I11
M8
M9
M10
M11
L8
L9
L10
L11
B8
B9
B10
B11
SRD2L
I12
I13
I14
I15
M12
M13
M14
M15
L12
L13
L14
L15
B12
B13
B14
B15
SRD2H
MODE1 SELECT BIT
DAG1 REGISTERS (DATA MEMORY)
DAG2 REGISTERS (PROGRAM MEMORY)
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 ...