IDT82P2282

The IDT82P2282 is a highly featured single device solution for T1/ E1/J1 trunks. Each link of the IDT82P2282 can be independently configured.

The configuration is performed through a SPI or parallel microprocessor interface.
 LINE INTERFACE - RECEIVE PATH In the receive path, the signals from the line side are coupled into the RTIPn and RRINGn pins and pass through an Impedance Terminator. An Adaptive Equalizer IDT82P2282 is provided to increase the sensitivity for small signals. Clock and data are recovered from the digital pulses output from the slicer. After passing through the Receive Jitter Attenuator (can be enabled or disabled), the recovered data is decoded using B8ZS (for T1/ J1) / HDB3 (for E1) or AMI line code rules and clocked into the Frame Processor. Loss of signal, line code violations and excessive zero are detected.

FRAMER - RECEIVE PATH
In T1/J1 Mode, the recovered data and clock of each link can be configured in Super Frame (SF), Extended Super Frame (ESF), T1 Digital Multiplexer (DM) or Switch Line Carrier - 96 (SLC-96) formats. (The T1 DM and SLC-96 formats only exist in T1 mode). The framing of IDT82P2282 can also be bypassed (unframed mode). The Framer detects and indicates the out of SF/ESF/DM/SLC-96 synchronization event, the Yellow, Red and AIS alarms. The Framer also detects the presence of inband loopback codes and bit-oriented messages. Frame Alignment Signal errors, CRC- 6 errors, out of SF/ESF/T1 DM/SLC-96 events and Frame Alignment position changes are counted. Up to three HDLC links (in ESF and T1 DM format) or two HDLC links (in SF and SLC-96 format) are provided to extract the HDLC message on the DL bit (in ESF format) / D bit in CH24 (in T1 DM format) or any arbitrary position. In the T1/J1 receive path, signaling debounce, signaling freeze, idle code substitution, digital milliwatt code insertion, idle code insertion, data inversion and pattern generation or detection are supported on a per-channel basis. An Elastic Store Buffer that supports controlled slip and adaptation to backplane timing may be enabled. In the Receive System Interface, various operating modes can be selected to output signals to the system.

In E1 Mode, the recovered data and clock of each link can be configured to frame to Basic Frame, CRC Multi-Frame and Signaling Multi- Frame. The framing can be bypassed (unframed mode). The Framer detects and indicates the following event: out of Basic Frame Sync, out of CRC Multi-Frame, out of Signaling Multi-Frame, Remote Alarm Indication signal and Remote Signaling Multi-Frame Alarm Indication signal.

The Framer also monitors Red and AIS alarms. Basic Frame Alignment Signal errors, Far End Block Errors (FEBE) and CRC errors are counted. Up to three HDLC links are provided to extract the HDLC message on TS16, the Sa National bits or any arbitrary timeslot. In the E1 receive path, signaling debounce, signaling freezing, idle code substitution, digital milliwatt code insertion, trunk conditioning, data inversion and pattern generation or detection are also supported on a per-timeslot basis. An Elastic Store Buffer that supports slip buffering and adaptation to backplane timing may be enabled. In the Receive System Interface, various operating modes can be selected to output signals to the system.

SYSTEM INTERFACE
On the system side, if the device is in T1/J1 mode, the data stream of 1.544 Mbit/s can be converted to/from the data stream of 2.048 Mbit/s by software configuration. In addition, the two links can be multiplexed to or de-multiplexed from a 8.192 Mbit/s bus. If the device is in E1 mode, the two links can be multiplexed to or de-multiplexed from a 8.192 Mbit/s bus.

FRAMER - TRANSMIT PATH
In the transmit path, the Transmit System Interface inputs the signals with various operating modes. In T1/J1 mode, the signals can be processed by a Transmit Payload Control to execute the signaling insertion, idle code substitution, data insertion, data inversion and test pattern generation or detection on a per-channel basis. The transmit path of each transceiver can be configured to generate SF, ESF, T1 DM or SLC- 96. The framer can also be disabled (unframed mode). The Framer can transmit Yellow alarm and AIS alarm. Inband loopback codes and bit oriented message can be transmitted. Up to three HDLC links (in ESF and T1 DM format) or two HDLC links (in SF and SLC-96 format) are provided to insert the HDLC message on the DL bit (in ESF format) / D bit in CH24 (in T1 DM format) or any arbitrary position. After passing through a Transmit Buffer, the processed data and clock are input to the Encoder.

In E1 mode, the signals can be processed by a Transmit Payload Control to execute the signaling insertion, idle code substitution, data insertion, data inversion and test pattern generation or detection on a per-timeslot basis. The transmit path of each transceiver can be configured to generate Basic Frame, CRC Multi-Frame and Signaling Multi- Frame. The framer can be disabled (unframed mode). The Framer can transmit Remote Alarm Indication signal, the Remote Signaling Multi- Frame Alarm Indication signal, AIS alarm and FEBE. Three HDLC links are provided to insert the HDLC message on TS16, the Sa National bits or any arbitrary timeslot. The processed data and clock are input to the Encoder.

LINE INTERFACE - TRANSMIT PATH
The data is encoded using AMI or B8ZS (for T1/J1) and HDB3 (for E1) line code rules. The Transmit Jitter Attenuator, if enabled, is provided with a FIFO in the transmit data path. A de-jittered clock is generated by an integrated digital phase-locked loop and is used to read data from the FIFO. The shapes of the pulses are user programmable to ensure that the T1/E1/J1 pulse template is met after the signal passing through different cable lengths and types. Bipolar violation can be inserted for diagnostic purposes if AMI line code rule is enabled. The signal is transmitted on the TTIPn and TRINGn pins through an Impedance Terminator.