Abstract: A circuit for transferring a n-bit phase value between circuits includes a system clock input, a n-bit phase value generator coupled to the system clock input generating a phase value output, and an edge output indicating the phase output value is valid, a latching clock delay circuit having an input coupled to the system clock input, an input coupled to the edge output, a variable phase delay circuit coupled to the phase value output, a delay adder having a first input coupled to the phase value output, a second input coupled to a delay offset signal, and an output coupled to the control input of the variable phase delay circuit, and a phase flip-flop having a data input coupled to the output of the variable phase delay circuit, a clock input coupled to a latching clock output of the variable output clock delay circuit and a Phase Out output.

Abstract: A transmission line sampling circuit for a T1 line is disclosed. A multi phase oscillator is connected to a plurality of state machines which are connected in parallel to a transmission line. The use of a plurality of state machines to sample the transmission line effectively increases the sample rate of the transmission line beyond that which can ordinarily be supported by a single phase oscillator running at the same frequency of the multi phase oscillator. The outputs of the plurality of state machines are provided to an arbitrator and to a MUX wherein the arbitrator decides which of the four state machines outputs should be switched through the MUX and produced transmitted on an output line.

Abstract: A transmission line sampling circuit for a T1 line is disclosed. A multi phase oscillator is connected to a plurality of state machines which are connected in parallel to a transmission line. The use of a plurality of state machines to sample the transmission line effectively increases the sample rate of the transmission line beyond that which can ordinarily be supported by a single phase oscillator running at the same frequency of the multi phase oscillator. The outputs of the plurality of state machines are provided to an arbitrator and to a MUX wherein the arbitrator decides which of the four state machines outputs should be switched through the MUX and produced transmitted on an output line.

Abstract: A circuit and method of adjusting a sample point for a data stream to account for intersymbol interference is disclosed herein. The system averages the amount of intersymbol interference occurring for a specific data pattern and uses this average value which reflects a phase difference between the leading edges of two pulses to determine at which clock count a sync pulse should issue to sample and read a data value.

Abstract: A pipe track has a groove in which a ladder is slidably mounted for movement between ends of the track. A pair of spaced, downwardly extending notches at one end of the groove permit the ladder to be pivoted downwardly to occupy a vertical position coplanar with the track; and a pair of spaced, upwardly extending notches at the other end of the groove permit the ladder to be pivoted upwardly to occupy a vertical position coplanar with the track.

Abstract: Method and apparatus for determining the integrity of a communications channel includes a first communications system connected to a communications channel with a receiving communications system attached to the other end of the chennel. The first communications system generates a discrete frequency at the low end of the bandwidth for reception by the receiving system. The receiving system measures the frequency and the power level of the first tone. The first communications system then inhibits transmission for a predetermined duration of time during which the receiving system measures the noise floor of the communications channel. A second tone is then generated at the high end of the channel bandwidth for reception by the receiving system. The receiving system then compares the measured power levels of the first and second tone and the noise floor with predetermined criteria and determines the integrity of the communications channel from this comparison.