
XRT79L71
PRELIMINARY
327
1-CHANNEL DS3/E3 CLEAR-CHANNEL FRAMERLIU COMBO - CC/HDLC ARCHITECTURE
REV. P2.0.0
In response to this "erred" condition, the Transmit DS3/E3 Framer block (within the "Near-End" Terminal) will
respond by setting the "A" bit, within the very next outbound E3 frame, to the value "1" in order to denote a
FEBE/REI event. More specifically, the Transmit DS3/E3 Framer block (within the "Near-End" Terminal) will
transmit an E3 frame (with the "A" bit-field set to "1") each time the corresponding Receive DS3/E3 Framer
block (also within the "Near-End" Terminal) detects a BIP-4 nibble within an E3 frame. Figure 151 presents an
illustration of the Transmit DS3/E3 Framer block sending the FEBE/REI indicator to the remote terminal
equipment.
For information on how the Receive DS3/E3 Framer block processes the "A" bit-fields within each incoming E3
The Transmit DS3/E3 Framer block provides the user with two options associated with transmitting the FEBE/
REI indicator (via the "A" bit).
Forced transmission of the FEBE/REI indicator (e.g., under Software Control)
Automatic transmission of the FEBE/REI indicator (in response to the Receive DS3/E3 Framer block
detecting BIP-4 nibble errors)
5.2.4.4.1
Forced Transmission of the FEBE/REI Indicator
FIGURE 150. A SIMPLE ILLUSTRATION OF A "NEAR-END" TERMINAL DETECTING BIP-4 NIBBLE ERRORS WITHIN ITS
INCOMING
E3 SIGNAL
FIGURE 151. A SIMPLE ILLUSTRATION OF THE "NEAR-END" TERMINAL EQUIPMENT TRANSMITTING THE FEBE/REI
INDICATOR TO THE REMOTE TERMINAL EQUIPMENT
Transmit E3
Framer
Receive E3
Framer
Near-End Terminal
Remote
Terminal
Equipment
Remote
Terminal
Equipment
BIP-4 Nibble
Locally Calculated
BIP-4 Nibble
0x0B
0x0A
Transmit E3
Framer
Receive E3
Framer
Near-End Terminal
Remote
Terminal
Equipment
Remote
Terminal
Equipment
1
A Bit