R
Chapter 3: Family Specific Considerations
1.The jitter of the source clock, to determine if it is appropriate for use as an input to a DCM.
2.The DCM configuration, to generate a 200 MHz clock on any appropriate DCM output (CLKFX, CLKDV, and so forth).
3.The jitter of the derived 200 MHz reference clock, to determine if it is appropriate for use as an input to an IDELAYCTRL.
For more information about the relevant timing parameters, see the
Warning: The fixed frequency requirement of the source clock precludes the use of the PCI bus clock, unless the design is used in an embedded/closed system where the PCI bus clock is known to be a fixed frequency. See “Bus Clock Usage” for additional information about the allowed behavior of the PCI bus clock in compliant systems.
Regional Clock Usage
Some
Designers must be aware of additional constraints imposed by the use of regional clocks.
32 | www.xilinx.com | PCI v3.0.151 Getting Started Guide |
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| UG157 August 31, 2005 |