DS3112
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1.2 Main DS3112 TEMPE Features
1.2.1 General
Features
Can be operated as a standalone T3 or E3 framer without any M13 or E13 multiplexing
T1/E1 FIFOs in the receive direction provide T1/E1 demultiplexed clocks with very little jitter
Two T1/E1 drop and insert ports
B3ZS/HDB3 encoder and decoder
T3 C-Bit Parity mode
All the receive T1/E1 ports can be clocked out on a common clock
All the transmit T1/E1 ports can be clocked in on a common clock
Generates gapped clocks that can be used as demand clocks in unchannelized T3/E3 applications
T1/E1 ports can be configured into a “loop-timed” mode
T3/E3 port interfaces can be either bipolar or unipolar
The clock, data, and control signals can be inverted to allow a glueless interface to other device
Loss of transmit and receive clock detect
1.2.2 T3/E3
Framer
Generates T3/E3 Alarm Indication Signal (AIS) and Remote Alarm Indication (RAI) alarms
Transmit framer pass through mode
Generates T3 idle signal
Detects the following T3/E3 alarms and events: Loss Of Signal (LOS), Loss Of Frame (LOF), Alarm
Indication Signal (AIS), Remote Alarm Indication (RAI), T3 idle signal, Change Of Frame Alignment
(COFA), B3ZS and HDB3 codewords being received, Severely Errored Framing Event (SEFE), and
T3 Application ID status indication
1.2.3 T2/E2
Framer
Generates T2/E2 Alarm Indication Signal (AIS) and Remote Alarm Indication (RAI) alarms
Generates Alarm Indication Signal (AIS) for T1/E1 data streams in both the transmit and receive
directions
Detects the following T2/E2 alarms and events: Loss Of Frame (LOF), Alarm Indication Signal
(AIS), and Remote Alarm Indication (RAI)
Detects T1 line loopback commands (C3 bit is the inverse of C1 and C2)
Generates T1 line loopback commands
1.2.4 HDLC
Controller
Designed to handle multiple LAPD messages without Host intervention
256 byte receive and transmit buffers are large enough to handle the three T3 messages (Path ID, Idle
Signal ID, and Test Signal ID) that are sent and received once a second which means the Host only
needs to access the HDLC Controller once a second
Handles all of the normal Layer 2 tasks such as zero stuffing/destuffing, CRC generation/checking,
abort generation/checking, flag generation/detection, and byte alignment
Programmable high and low watermarks for the FIFO
HDLC Controller can be used in either the T3 C-Bit Parity Mode or in the Sn Bits in the E3 Mode
1.2.5 FEAC
Controller
Designed to handle multiple FEAC codewords without Host intervention
Receive FEAC automatically validates incoming codewords and stores them in a 4-byte FIFO
Transmit FEAC can be configured to send either one codeword, or constant codewords, or two
different codewords back-to-back to create T3 Line Loopback commands
FEAC Controller can be used in either the T3 C-Bit Parity Mode or in the Sn Bits in the E3 Mode