Conditional Sequencing
3-20
ADSP-2126x SHARC Processor Hardware Reference
The two conditions that do not have complements are
LCE/NOT LCE
(loop
counter expired/not expired) and
TRUE
/
FOREVER
. The context of these con-
dition codes determines their interpretation. Programs should use
TRUE
and
NOT LCE
in conditional (
IF
) instructions. Programs should use
FOR-
EVER
and
LCE
to specify loop (
DO
/
UNTIL
) termination. A
DO FOREVER
instruction executes a loop indefinitely, until an interrupt or reset
intervenes.
There are some restrictions on how programs may use conditions in
DO
/
UNTIL
loops. For more information, see
and
“Restrictions on Short Loops” on page 3-28
.
Flag Input
Flag0 asserted
FI0 = 1
FLAG0_IN
Flag0 not asserted
FI0 = 0
NOT FLAG0_IN
Flag1 asserted
FI1 = 1
FLAG1_IN
Flag1 not asserted
FI1 = 0
NOT FLAG1_IN
Flag2 asserted
FI2 = 1
FLAG2_IN
Flag2 not asserted
FI2 = 0
NOT FLAG2_IN
Flag3 asserted
FI3 = 1
FLAG3_IN
Flag3 not asserted
FI3 = 0
NOT FLAG3_IN
Hardware Loop
Loop counter expired (Do)
CURLCNTR = 1
LCE
Loop counter not expired (IF)
CURLCNTR
1
NOT ICE
Always false (Do)
Always
FOREVER
Always true (IF)
Always
TRUE
1 ALU greater than (GT) is true if: [
AF
and (
AN
xor (
AV
and
ALUSAT
)) or (
AF
and
AN
)] or
AZ
= 0
2 ALU less than (LT) is true if: [
AF
and (
AN
xor (
AV
and
ALUSAT
)) or (
AF
and
AN
and
AZ
)] = 1
3 ALU greater equal (GE) is true if: [
AF
and (
AN
xor (
AV
and
ALUSAT
)) or (
AF
and
AN
and
AZ
)] = 0
4 ALU lesser or equal (LE) is true if: [
AF
and (
AN
xor (
AV
and
ALUSAT
)) or (
AF
and
AN
)] or
AZ
= 1
Table 3-6. IF Condition and DO/UNTIL Termination
Mnemonics (Cont’d)
Condition From
Description
True if…
Mnemonic
Содержание ADSP-21261 SHARC
Страница 30: ...Contents xxx ADSP 2126x SHARC Processor Hardware Reference ...
Страница 40: ...Register Diagram Conventions xl ADSP 2126x SHARC Processor Hardware Reference ...
Страница 58: ...Differences From Previous SHARCs 1 18 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 112: ...Secondary Processing Element PEy 2 54 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 178: ...Summary 3 66 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 204: ...DAG Instruction Summary 4 26 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 322: ...Setting Up DMA 7 32 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 436: ...SPORT Programming Examples 9 86 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 521: ...ADSP 2126x SHARC Processor Hardware Reference 11 31 Input Data Port rts IDP_ISR end ...
Страница 522: ...Input Data Port Programming Example 11 32 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 590: ...Timer Programming Examples 14 20 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 796: ...I O Processor Registers A 174 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 800: ...B 4 ADSP 2126x SHARC Processor Core Manual ...
Страница 846: ...Index I 36 ADSP 2126x SHARC Processor Hardware Reference ...