
Frame Sync Outputs
13-4
ADSP-2126x SHARC Processor Hardware Reference
than 50%. The low period of the output clock is one input clock period
more than the high period of the output clock.
A PCG clock output cannot be fed to its own input. Setting
SRU_-
CLK3[4:0] = 28
connects
PCG_EXTA_I
to logic low, not to
PCG_CLKA_O
. Setting
SRU_CLK3[9:5] = 29
connects
PCG_EXTB_I
to
logic low, not to
PCG_CLKB_0
.
Frame Sync Outputs
Each of the two units (A and B) also produces a synchronization signal for
framing serial data. The frame sync outputs are much more flexible since
they need to accommodate the wide variety of serial protocols used by
peripherals.
There are two modes of operation for the PCG frame sync. The divisor
field determines if the frame sync will operate in Normal mode (divisor >
1) or Bypass mode (divisor = 0 or 1).
Frame Sync
For a given frame sync, the output is determined by the following:
•
Divisor.
A 20-bit divisor of the input clock that determines the
period of the frame sync. When set to zero or one, the frame sync
operates in Bypass mode, otherwise it operates in Normal mode.
•
Phase.
A 20-bit value that determines the phase relationship
between the clock output and the frame sync output. Settings for
phase can be anywhere between zero to
DIV - 1
.
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 ...