Core Registers
A-20
ADSP-2126x SHARC Processor Hardware Reference
User-Defined Status Registers (USTATx)
These are non-memory-mapped, universal, system registers (
Ureg
and
Sreg
). The reset value for these registers is 0x0000 0000. The
USTATx
reg-
isters are user-defined, general-purpose status registers. Programs can use
these 32-bit registers with bit-wise instructions (
SET
,
CLEAR
,
TEST
, and oth-
ers). Often, programs use these registers for low overhead, general-purpose
flags or for temporary 32-bit storage of data.
Processing Element Registers
Except for the
PX
register, the DSP’s Processing Element registers store
data for each element’s ALU, multiplier, and shifter. The inputs and out-
puts for processing element operations go through these registers. The
PX
register lets programs transfer data between the data buses, but cannot be
an input or output in a calculation.
24
SSEM
Status Stack Empty.
Indicates if the status stack is empty (if 1) or
not empty (if 0)—not sticky, cleared by a Push.
25
LSOV
Loop Stack Overflow.
Indicates if the loop counter stack and loop
stack are overflowed (if 1) or not overflowed (if 0)—sticky bit.
26
LSEM
Loop Stack Empty.
Indicates if the loop counter stack and loop
stack are empty (if 1) or not empty (if 0)—not sticky, cleared by a
Push.
31–27
Reserved
Table A-5. STKYx and STKYy Register Bit Descriptions (Cont’d)
Bit
Name
Description:
shows bits in both STKYx/y
shows bits in STKYx only
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 ...