GENERAL DESCRIPTION
The DS2182A T1 line monitor chip is a monolithic CMOS device designed to monitor real-time performance on T1 lines. The DS2182A frames to the data on the line, counts errors, and supplies detailed information about the status and condition of the line. Large on-board counters allow the accumulation of errors for extended periods, which permits a single CPU to monitor many T1 lines. Output clocks that are synchronized to the incoming data stream are provided for easy extraction of S-bits, FDL bits, signaling bits, and channel data. The DS2182A meets the requirements of ANSI T1.231.

FEATURES
■ Performs Framing and Monitoring Functions
■ Supports Superframe and Extended Superframe Formats
■ Four On-Board Error Counters:
    16-Bit Bipolar Violation
    8-Bit CRC
    8-Bit OOF
    8-Bit Frame Bit Error
■ Indication of the Following:
    Yellow and Blue Alarms
    Incoming B8ZS Codewords
    8 and 16 Zero Strings
    Change-of-Frame Alignment
    Loss of Sync
    Carrier Loss
■ Simple Serial Interface Used for Configuration, Control, and Status Monitoring
■ Burst Mode Allows Quick Access to Counters for Status Updates
■ Automatic Counter Reset Feature
■ Single 5V Supply; Low-Power CMOS Technology
■ Available in 28-Pin DIP and 28-Pin PLCC
■ Upward-Compatible from the Original DS2182

The DS2182A includes the following changes from the original DS2182:
■ Ability to Count Excessive Zeros
■ Severely Errored-Framing-Event Indication
■ Updated AIS Detection
■ Updated RCL Detection
■ AIS and RCL Alarm Clear Indications