Specifications

2-73
Cisco IGX 8400 Series Provisioning Guide, Release 9.3.3 and Later Releases
OL-1166-04
Chapter 2 Cisco IGX 8400 Series Cards
Frame Relay Module
Configuring an FRM with FRI-X.21 Back Card
FRI configuration supports one to four ports. The configuration depends on the maximum speed
requirement (the card itself has a maximum composite speed).
Note The following port speeds are supported on the FRM with FRI-X.21 back card: 56, 64, 112, 128, 168,
192, 224, 256, 320, 336, 384, 448, 512, 640, 672, 768, 896, 960, 1024, 1280, 1344, 1536, 1920, and
2048 kbps.
Data Clocking on the FRI-X.21 Back Card
Unlike the FRI-V.35, the FRI-X.21 only supports normal clock mode. Depending on the configuration
of the FRI, the direction of the clock and data lines may be reversed according to the following rules (see
Figure 2-33):
• If the FRI is configured as a DCE, it provides a clock signal to the user device (DTE) on the S clock
lead (pins 6/13).
• If the FRI is configured as a DTE, the FRI receives a clock signal from the user device (DCE) on
the S clock lead (pins 6/13).
Figure 2-33 FR Data Clocking Modes on the FRI-X.21 Back Card
User device
(DCE)
FRI
(DTE)
TxD
TxS
A. Normal clocking - FRI as DTE
XD
RD
H8075
RxD
CLK
User device
(DTE)
FRI
(DCE)
TxD
TxS
B. Normal clocking - FRI as DCE
XD
RD
RxD
CLK