The RSLIC-CODEC chipset is comprised of one four-channel programmable PCM CODEC (IDT82V1074) and four single-channel ringing SLICs (IDT82V1671). The chipset provides a total solution for line card designs. In addition to providing a complete software programmable solution for BORSCHT, additional functions such as FSK generator, Universal Tone Detection (UTD) unit, tone generators, ringing generator, Integrated Test and Diagnosis Functions (ITDF), line polarity reversal and three-party conference are integrated in to the chipset. The high integration of system functions reduces board space requirements of the line card and saves cost. The chipset is fully programmable via a Microprocessor Interface (MPI) or a General Circuit Interface (GCI). In both MPI and GCI modes, the chipset supports A/-law companding format or linear data format. Programmable digital filters on the chipset provide the necessary transmit and receive filtering to realize impedance matching, transhybrid balance, frequency response correction and transmit/receive gains adjustment. The full programmability optimizes the performance of line card products and allows one line card to adapt to different requirements worldwide.