Local Port Clocked Mode - Renesas IDT 89HPES48H12G2 User Manual

IDT Clocking
Notes
PES48H12G2 User Manual
Figure 4.3 Clocking Connection for a Port in Global Clocked Mode, Non-Common Clocked Configuration

Local Port Clocked Mode

A port in local port clocked mode uses the corresponding port clock (PxCLK) input for receiving and
transmitting serial data. If the supplied port reference clock input uses SSC, then the global reference clock
input must not use SSC. Depending on the system configuration, a port in this mode may employ the
common Refclk or separate Refclk architectures defined by the PCIe Base Specification Revision 2.0.
Figure 4.4 shows the clock connection between a PES48H12G2 port and it's link partner, when the
switch port operates in local port clocked mode with a common clock configuration.
Figure 4.4 Clocking Connection for a Port in Local Port Clocked Mode, in a Common Clocked Configuration
Figure 4.5 shows the clock connection between a PES48H12G2 port and it's link partner, when the
switch port operates in local port clocked mode with a non-common clock configuration. This configuration
is not expected to be used in practice but is shown here for completeness.
Switch
GCLK
Clock
Generator
Port
Clock
Link Partner
Generator
Switch
GCLK
Clock
Generator
PxCLK
Clock
Link Partner
Generator
4 - 5
Port
April 5, 2013