The TP3410 is a complete monolithic transceiver for ISDN Basic Access data transmission at either end of the U interface Fully compatible with ANSI specification T1 601 it is built on National's advanced double-metal CMOS process and requires only a single a 5V power supply A total of 160 kbps full-duplex transmission on a single twisted-pair is provided with user-accessible channels including 2 `B' channels each at 64 kbps 1 `D' channel at 16 kbps and an additional 4 kbps for loop maintenance 12 kbps of bandwidth is reserved for framing 2B1Q Line coding is used in which pairs of binary bits are coded into 1 of 4 quantum levels for transmission at 80k symbols sec (hence 2 Binary 1 Quaternary) To meet the very demanding specifications for k1 in 10e7 Bit Error Rate even on long loops with crosstalk the device includes 2 Adaptive Digital Signal Processors 2 Digital Phase-locked Loops and a controller for automatic activation The digital interface on the device can be programmed for compatibility with either of two types of control interface for chip control and access to all spare bits In one mode a Microwire serial control interface is used together with a 2B a D digital interface which is compatible with the Time-division Multiplexed format of PCM Combo devices and backplanes This mode allows independent time-slot assignment for the 2 B channels and the D channel Alternatively the GCI (General Circuit Interface) may be selected in which the 2B a D data is multiplexed together with control spare bits and loop maintenance data on 4 pins