Abstract: A heartbeat monitor for wearing during exercise and receiving audio heartbeat information includes a pulse rate detector having an infrared source and an infrared sensor on a flexible cup-shaped ear piece which fits into the ear canal.

Abstract: A PCM modem equalizer includes an RBS estimator and decision modulator in conjunction with an adaptive equalizer such as a conventional decision feedback equalizer (DFE). The RBS estimator and decision modulator receives error signals from the second summer in the equalizer, receives the estimated R signals from the first summer of the equalizer, and outputs a gain correction signal which is applied to the output of the reference generator before the reference generator output is applied to the feedback equalizer and the second summer. The methods of the invention are based on the recognition that the effects of RBS can be detected in the amplitude modulation of the main training sequence stream. The modulation will occur in a periodic repetitive pattern of length 6*T where T is the symbol interval. Therefore, the invention applies a corrective gain to the decision in each time slot in a periodic manner having the same period 6*T. For each time interval T.sub.

Abstract: A host signal processor (HSP) modem which includes procedures executed in response to interrupts has a CPU utilization control procedure which uses the numbers of clock cycles associated with modem tasks and the total number of clock cycles between interrupts to select a task for execution during the interrupts. The utilization control procedure changes or selects the task as required to automatically adjust the HSP modem for the available processing power and a desired maximum percentage utilization of a host computer. For example, the task can be selected to match the data transfer rate of the HSP modem with available processing power. The HSP modem is more robust and is operable in host computers having relatively low processing power. A user can change the maximum utilization of processing power used by the HSP modem so that more processing power is available for other purposes.

Abstract: A process for transmitting data selects sample values that represent data symbols and then converts the sample values to voltage levels in a transmitted PAM signal. A receiver samples the PAM signal and identifies the data symbols from the sampled voltage levels. At least some of the data symbols have multiple alternative representations; and for a data symbol having multiple alternatives, a sample value is selected to reduce low and high frequency components in the PAM signal. Accordingly, the PAM signal carries less information at low and high frequencies and is less disturbed by transformers, low pass filters, and local loop impairment in the transmission channel. The process for selecting sample values determines a weighted average of the lowest and highest frequency components. The weighting of the average can be selected according to a measured frequency response of the channel during initialization.

Abstract: A host signal processor (HSP) modem has a software interface between HSP modem hardware and native audio hardware in a host computer. No hard wire connections between modem hardware and audio hardware are required for synchronization. Instead, a software clock recovery system matches a transfer rate of the HSP modem hardware and a transfer rate of the audio hardware by duplicating or deleting samples. The software interface allows the native audio hardware to make audible the handshaking sequence during modem connections which eliminates the need for a speaker and speaker drivers in the modem hardware. The combination of HSP modem hardware, audio hardware, and software executed by the host computer also allows the HSP modem to perform voice communication such as telephone or speakerphone functions.

Abstract: An communication system such as a host signal processing modem includes a host computer and a device that is coupled to communication lines and a host processor in the host computer. In a normal operating mode, the device generates periodic interrupts that cause the host processor to execute a software portion of the communication system. The software portion communicates with the device and implements protocols required to maintain communications with a remote system via communication lines. In a wait mode of the device, interrupts from the device to the host processor are suspended and selection logic in the device selects a communication signal such as a ring signal from the telephone lines as an interrupt to the host processor. While in wait mode, a power management system can place the system in a sleep mode because the periodic interrupts are suspended and do not indicate system activity that would prevent use of the sleep mode.

Abstract: A server located at a first location for recording and managing communications for transcription generated at a second location. Clients contact the server to store communications for transcription. The client is given the option to create a user configurable profile that defines user identification data and recording options for that client. The user identification data includes a user identification number and an audible user identification which is associated with each user identification number. The communications are recorded based on the recording options in the user configurable profile. Exemplary recording options include file integrity and audio archiving. The server also provides the user with the ability to withhold a recording for completion at a later time.

Abstract: A computer system includes a software UART emulation and uses standard operating system protocols to minimized the chance of I/O conflicts between a serial device having a UART and a non-standard serial device which communicates through the UART emulation. A COM driver which can replace a standard COM driver in an operating environment such as provided by Microsoft WINDOWS.TM. contains the UART emulation. The COM driver can also include a software modem that is accessed through the UART emulation in the same manner as a modem having a hardware UART. The COM driver also sets the device address of the non-standard device on an ISA bus by determining the device addresses of COM port I/O slots used by UARTs, sending a predetermined pattern on the ISA bus to indicate a device address is to come, and then sending a value indicating a device address not used by the UARTs. The pattern has a length sufficient to make inadvertent generation of the pattern unlikely.

Abstract: Connecting a null modem cable between first and second communications ports of a host computer and executing a background routing program which transfers information between the second communications ports and a host signal processor (HSP) modem enables a DOS application which is configured to directly access a hardware UART of the first communication port to communicate with the HSP modem even if the HSP lacks a hardware UART. In one embodiment, the DOS application runs in a DOS virtual machine in a Windows.TM. operating system, and the routing application runs in a system virtual machine. The HSP modem includes a software portion inside a port driver in the operating system kernel. The routing program is started before the DOS application, executed in the background of the DOS application, and removed after completion of the DOS application.

Abstract: An HSP communications system contains a host computer which executes a software modem program and a device containing a circular buffer and a D/A converter. Typically, the host executes update routines in response to interrupts from the device and writes to the circular buffer digital samples representing amplitudes of an analog signal complying with a desired communication protocol. The samples pass through the circular buffer to the D/A converter which converts the samples into an analog communication signal. In environments such as multi-tasking systems, the host may occasionally skip interrupts and not provide new samples when required. In this case, the D/A converter reuses samples in the circular buffer to generate a maintenance signal. The maintenance signal typically does not convey correct data but is sufficient to maintain a communication link and prevent a remote device from disconnecting or entering a retrain mode.

Abstract: A distributed, digital voice/data communications and switching system for connecting stations which may provide voice-only transmission, data only or voice and data. The system comprises one or more physical nodes, each serving (in an exemplary case) up to about 30 ports (i.e., station interfaces); nodes may be geographically distributed on the user's premises or one or more nodes may be collected together at a common location. The nodes are interconnected via a hierarchical network configuration formed of at least two, generally three, and perhaps even four interlocking networks. The first network is a slotted ring (the "regional" ring) employing coaxial cable to connect the nodes; it carries all control messages transmitted among the nodes, as well as the users' data traffic, using a frame which circulates continuously at about 20 Mbps. The second network is a "star" arrangement carrying PCM-encoded digitized voice traffic; at the hub of the star, in one of the nodes, is a digital voice switch.

Abstract: A terminal block cover provides a cover body having a latch mechanism depending from a side edge of the cover and a hinge mechanism depending from the opposite side edge. The hinge mechanism includes a clip that engages the terminal block's fanning strip, a separable hinge connected between the clip and cover body for permitting removal of the cover body from the terminal block, and a locking device that prevents the cover body from being removed from the terminal block except when it is in a predetermined rotational position on the hinge. The clip provides a prong that engages the fanning strip to index the clip in a fixed position so that the cover body can be reinstalled at the original position. In addition, the clip is held to the hinge mechanism by spring fingers on the hinge pin housing, which cooperate with the locking device to hold the clips in attachment to the cover body even when not installed on a terminal block.

Abstract: A communication system is provided which allows closed circuit television pictures to be transmitted from conventional TV cameras to conventional monitors via an ordinary pair of wires, for example, telephone wires, lamp cord, BX cable, etc., over limited distances without measurable degradation of picture quality. A balanced system is provided with dual inputs and outputs so that the system can accommodate simultaneous transmission of audio or other data. Adapters are provided on the receiving end and on the sending end which provide conversion, impedance matching, and the frequency compensation required in order to provide uniform frequency response for the quality transmission of television as well as audio and/or other data.

Abstract: Disclosed is a method and apparatus for selectively distributing on a multiple channel television system information previously transmitted and received in the Baudot code. The transmitted information is encoded into a sequence of Baudot characters to include a combination of figure shift and/or letter shift characters which identifies the category or type of information contained in the sequence. Upon receipt, the sequence is decoded to determine the category of information contained therein and then the information is applied to one of a plurality of storage areas in memory, with the particular storage area selected being dependent upon the determination of the information category. After an information sequence has been received, decoded and stored in one of the storage areas, it is then applied to one or more selected channels of the multiple channel television system for display on television receivers tuned to those selected channels.