4-44 Cisco IGX 8400 Series Reference
Network Trunk Module
Table4-20 Data and Control Leads Supported with BC-SR
Y1 Interface Back Card (BC-Y1)
The BC-Y1 back card provides a Japanese Y1 trunk interface for an NTM. The BC-Y1 can reside
in any rear slot 3 through 8 in an Cisco IGX 8410, 3 through 16 in an Cisco IGX 8420, or 3 through
32 in an Cisco IGX 8430. The BC-Y1 provides:
•An interface to Japanese “Y” Trunk (Y1) lines
•Support for Y1 trunk formatted signaling
•Support for 24-channel, 1.544 Mbps operation
•Support for fractional rates
•Coded Mark Inversion (CMI) line coding
•Statistics for Y1 line events (such as loss of framing, loss of signal, and framing errors.)
•Support for local and remote loopback at the Y1 interface and the local bus interface for fault
isolation
The BC-Y1 supports two clock modes. These are normal clocking and loop timing. The system
operatorselects the mode through software control. Normal clocking uses the receive clock from the
network for incoming data and supplies the transmit clock for outgoing data. This clock can be used
to synchronize the node.
Loop timing uses the receive clock from the network for the incoming data and turns the receive
clock around for timing the transmit data.
Figure 4-26 and Table4-21 provide descriptions of the BC-Y1 status LEDs and connections on the
faceplate. When you correlate the items in the figure and table, read from the top to the bottom.
Transmit Receive
Lead Name Interface Lead Name Interface
TX Transmit data All RX Receive data All
RTS Request to Send V.35 CTS Clear to Send V.35
DTR/C Data Terminal Ready All DSR/I Data Set Ready All
LL Local Loop EIA/TIA-422 DCD Data carrier select V.35
RL Remote Loop EIA/TIA-422 RI/IC Ring Incoming Call V.35
IS Terminal In Service EIA/TIA-422 TM Test mode V.35
SS Select standby V.35 SB Standby indicator
SF Sig rate select SI Signalling rate