Cisco UBR7246VXR Installation Manual page 26

Figure A-2
PA
PRI
SRC
PA
SEC
SRC
Figure A-3
PA
PRI
SRC
PA
SEC
SRC
Cisco Cable Clock Card Hardware Installation Guide for the Cisco uBR7246VXR Universal Broadband Router
A-2
Secondary External Clock Source
Port adapters w/
internal clocking
PA PA
Midplane
clk mux
Clock card primary source to midplane 8 kHz
Secondary External Clock Source Driving Midplane
Port adapters w/
internal clocking
PA PA
Midplane
clk mux
Clock card primary source to midplane 8 kHz
External SRCs
PRI SEC
Clock card
clk mux
PRI clk
PRI LOS
SEC clk
SEC LOS
No cable clock force secondary
source-midplane
External SRCs
PRI SEC
Clock card
clk mux
PRI clk
PRI LOS
SEC clk
SEC LOS
No cable clock force secondary
source-midplane
Appendix A Clock Source Paths
Clock recovery
and filter chips
20.48
MHz
To line
cards
Cable clock
Clock recovery
and filter chips
20.48
MHz
To line
cards
Cable clock
OL-26705-01