Branches and Sequencing
3-12
ADSP-2126x SHARC Processor Hardware Reference
2. Pops the status stack if the
ASTATx/y
and
MODE1
status registers that
have been pushed for interrupts
IRQ2-0
or timers.
There are a number of parameters that can be specified for branching
instructions:
• Branches can be direct or indirect. For direct branches, the
sequencer generates the address; for indirect branches, the PM data
address generator (DAG2) produces the address
• Direct branches are
JUMP
or
CALL
/
RETURN
instructions that use an
absolute—not changing at run time—address (such as a program
label) or use a PC-relative address. Some instruction examples that
cause a direct branch are:
CALL fft1024; /* Where fft1024 is an address label */
JUMP (pc,10); /* Where (pc,10) is a PC-relative address */
Indirect branches are
JUMP
or
CALL
/
RETURN
instructions that use a
dynamic address that comes from the PM data address generator
(
DAG2
). For more information on the data address generator, see
“Data Address Generators” on page 4-1
. Some instruction exam-
ples that cause an indirect branch are:
JUMP (i12, m8); /* where (m8,i12) are DAG2 registers */
CALL (i13, m9); /* where (m9,i13) are DAG2 registers */
Conditional Branches
The sequencer supports conditional branches. These conditional branches
are
JUMP
or
CALL
/
RETURN
instructions whose execution is based on testing
an
IF
condition. For more information on condition types in
IF
condition
instructions, see
“Conditional Sequencing” on page 3-17
DSP’s Single-Instruction, Multiple-Data (SIMD) mode influences the
execution of conditional branches.
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 ...