Abstract: A system that provides additional voice lines with data over a single two-wire subscriber loop. At the subscriber premise, one or more telephone instruments and data devices are connected to a digital modem into either a voice or a data interface. Analog voice signals are PCM sampled then packetized, and voice and data packets are transmitted to a CO modem over the subscriber loop. The CO modem depacketizes the voice packets into PCM format and transmits PCM voice information to a CO switch over a standard digital trunk interface. Data packets are routed to a data network. Voice packets are given transmission priority over data packets to ensures that voice is transported in the presence of data with low latency.

Abstract: A central processing unit arrangement for detecting a fault in a central processing unit system that includes a master processor and a slave processor. Master and slave processors are resynchronized at every bus cycle by conditioning the processors' READY signal with the ADS (address status) signals from each processor (ADS indicates that an access cycle has begun and a valid address is present on the address bus). This method of synchronization was selected over the more traditional method of lock-step, which was deemed impractical to implement given the timing constraints of a high speed bus. Also, the dual processors may not always begin their respective bus cycles on the same clock. In addition, it is necessary to synchronize processors for the first instruction fetch following a reset, because the time of completion of an internal self-test may not be deterministic.