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 a number of 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 onboard 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 code words
    – 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
■ The DS2182A is upward-compatible from the original DS2182

The updated 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