ADSP-2126x SHARC Processor Hardware Reference
3-63
Program Sequencer
list the registers within and related to the pro-
gram sequencer. All registers in the program sequencer are universal
registers (
Uregs
), so they are accessible to other universal registers and to
data memory. All of the sequencer’s registers and the top of stacks are
readable and writable, except for the fetch address, decode address, and
PC. Pushing or popping the PC stack is done with a write to the PC stack
pointer, which is readable and writable. Pushing or popping the loop
address stack requires explicit instructions.
A set of system control registers configures or provides input to the
sequencer. These registers appear across the top and within the interrupt
controller and are shown in
. A bit manipulation
instruction permits setting, clearing, toggling, or testing specific bits in
the system registers. For information on this instruction (Bit), see
SHARC
Processor Programming Reference
. Writes to some of these registers do not
take effect on the next cycle. For example, after a write to the
MODE1
regis-
ter enables ALU saturation mode, the change takes effect two cycles after
the write. Also, some of these registers do not update on the cycle immedi-
ately following a write. An extra cycle is required before a register read
returns the new value.
With the lists of sequencer and system registers,
summarize the number of extra cycles (latency) for a write to
take effect (effect latency) and for a new value to appear in the register
(read latency). A “0” indicates that the write takes effect or appears in the
register on the next cycle after the write instruction is executed, and a “1”
indicates one extra cycle.
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 ...