Frame Sync Outputs
13-6
ADSP-2126x SHARC Processor Hardware Reference
through the
MISCA4_I
(for PCGA) and
MISCA5_I
(for PCGB) signals of the
SRU_EXT_MISCA
register.
For more information, see “Miscellaneous SRU
Registers (SRU_EXT_MISCx, Group E)” on page A-132.
Synchronization with the external clock is enabled by setting bit 25 of the
SRU_CLK2
register for PCGA frame sync output and bit 10 of the
SRU_CLK3
register for PCGB frame sync output.
For more information, see “Clock
Routing Control Registers (SRU_CLKx, Group A)” on page A-114.
The
phase must be programmed to three, so that the rising edge of the external
clock is in sync with the frame sync. Programming should occur in the fol-
lowing order:
1. Program PCG control registers
SRU_EXT_MISCA
,
SRU_CLK2
and
SRU_CLK3
as mentioned above.
2. Enable the clock, frame sync, or both. In other words, program all
the values before enabling the PCG (clock and frame sync).
Since the rising edge of the external clock is used to synchronize
with the frame sync, the frame sync output is not generated until a
rising edge of the external clock is sensed.
The clock output cannot be aligned with the rising edge of the external
clock as there is no phase programmability. Once
CLKA
and
CLKB
have been
enabled, by programming bit 31 of
PCG_CTLA_0
and
PCG_CTLB_0
registers
Figure 13-2. Clock Output Synchronization with External Clock
FSA
(OUTP UT)
PCGx_CLKIN
EXT CLK
(INPUT)
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 ...