The DS2152 T1 Enhanced Single-Chip Transceiver contains all of the necessary functions for connection to T1 lines, whether they be DS-1 long haul or DSX-1 short haul. It has complete DS1/ISDN-PRI transceiver functionality, can handle both long and short haul trunks, generates DSX-1 and CSU line build outs, supports D4, ESF, and SLC-96R formats, has dual onboard two-frame elastic store slip buffers that can connect to asynchronous backplanes up to 8.192 MHz, supports 8-bit parallel control port, can extract and insert robbed-bit signaling, detects and generates RAI and AIS alarms, has programmable output clocks for Fractional T1, fully independent transmit and receive functionality, integral HDLC controller with 16-byte buffers for the FDL, generates and detects in-band loop codes from 1 to 8 bits in length including CSU loop codes, contains ANSI 1's density monitor and enforcer, large path and line error counters including BPV, CV, CRC6, and framing bit errors, pin compatible with DS2154 E1 Enhanced Single-Chip Transceiver, operates on 5V supply, low power CMOS, and comes in a 100-pin 14mm2 body LQFP package.