Abstract: A method and system are disclosed for searching a remote database utilizing a telephone device in communication with a data processing system. The data processing system has access to the remote database and the telephone device includes transmitter components for transmitting dual-tone multifrequency signals, wherein the dual-tone multifrequency signals are generated manipulating a keypad associated with the telephone device. The keypad has individually depressible alpha-numeric keys that may be utilized to generate a query and to send commands to the data processing system. The method of the present invention includes prompting the user to enter a query utilizing the depressible alpha-numeric keys on the keypad. As the query is input from the user, the data processing system searches the database to locate entries within the database corresponding to current state of the query.

Abstract: A method and apparatus for powering down a computer system while saving the state of the system at power down is disclosed. The system maintains the capability to suspend the execution of an application program operating on the system at any point and resuming execution of the application program at that same point at a later time. The time at which the system may be powered down and then powered back up again is totally arbitrary and depends only upon the user of the system. At the time the system is powered off, the contents of all active registers as well as the states of all I/O devices in the system are stored in a special save area of system memory. This special save area is provided with power during the suspended time in order to retain the state of the system at the time it was powered down. By using this special save suspend area, the main memory area of the system is available to any application programs independently of the system save memory requirements.

Abstract: A method for creating on-line presentations on a computer display using a complier, a compressor, and a processor. The complier converts control commands in source code format into object code format in order to specify how the information in an on-line presentation is to be presented on the display. The complier also creates a file identifying the image data to be used in the presentation. This file contains the names of the display units describing the image data used to indicate which of the uncompressed image data is to be operated upon by the compressor. The compressor formats and compresses the displayable picture elements of text and graphic shapes which have been used to create the on-line presentation. The processor then loads and executes the object code of the control commands with its corresponding picture elements of image data to create the on-line presentation. The control commands are generated totally separate from the image data.

Abstract: A microprogrammed parallel processor including a plurality of subprocessors operates under the control of microinstructions. Each microinstruction contains a plurality of micro-operations each of which requires one or more subprocessors for execution. All micro-operations for which required subprocessors are available are immediately carried out. Any remaining micro-operations within a microinstruction which are not executed due to lack of subprocessor availability are recycled. These remaining micro-operations are executed in subsequent cycles as a required subprocessor becomes available. The entire microinstruction is not recycled but only those portions of it, i.e., the unexecuted micro-operations, are recycled and executed in a subsequent cycle. The microinstruction being executed is stored in a latch until all micro-operations within the microinstruction are executed. At that time, the next microinstruction is fetched into the latch.

Abstract: Automatic gain control in a digital signal processor. An incoming electrical signal is sampled and multiplied by a gain factor with the resulting product compared to a constantly changing maximum value. If the magnitude of the changing maximum value lies outside a predetermined range of values, then the gain factor is adjusted proportionally to the error calculated by the amount the maximum value is outside the threshold range. In an alternative embodiment, the gain is adjusted according to whether or not one of the resulting products lies outside such upper and lower threshold range. The running maximum value decays with time in order to allow the automatic gain control to rack a signal which slowly weakens in strength. A time dependent factor enables the gain to be adjusted much more radically when a signal is first received.

Abstract: A method and apparatus expands the capability of an instruction prefetch buffer. The method and apparatus enables the instruction prefetch buffer to distinguish between old prefetches that occurred before a branch in an instruction stream and new prefetches which occurred after the branch in the instruction stream. A control tag is generated each time a request for an instruction is sent to a storage. The returning instruction has appended thereto the original control tag which is then compared to the current value of control tag in the instruction prefetch buffer. If the two values match, then this is an indication that a branch has not occurred and the instruction is still required. However, if the two values of the control tag are not equal, then this is an indication that a branch in the instruction stream has occurred and that the instruction being sent from storage to the buffer is no longer required.

Abstract: This invention enables voice energy to be distinguished from energy due to other sources such as telephone call progress signals. A portion of the audio spectrum is divided into a high and into a low frequency band and the energy content of these bands is examined. The audio energy of a signal is passed through a set of filters and compared. A frequency boundary crossing of an input signal subsequent to filtering is used to signify the receipt of a voice signal. By operating in this manner, voice, whose predominant frequency switches in a random fashion from being greater than to less than a cutoff frequency, can be distinguished from other signals either below or above the cutoff frequencies of the filters. The detection of voice energy is not begun until a predetermined threshold of energy has been received for a specified period of time. This specified period of time need not be continuous after a ringback signal is received.

Abstract: In a word processing system, a text stream is stored on a direct access storage device (DASD) for recall and editing. The text stream is organized into a document that is stored on the DASD as a data set. The data set comprises an index portion and a portion containing text records. The index portion is divided into nodes, of which the primary node is called the root node. A method called shadowing is introduced to protect index nodes from the loss of significant data. Status indicators are defined and maintained so that access to a data set for normal system operation may be prevented where there is significant chance that the data set index has errors or is inconsistent to the extent that the normal high performance access method routines may not be able to use the index or may cause inadvertent loss of valid text data.

Abstract: An application programming interface enables system hardware resources to interact with application programs to provide a plurality of signal processing functions. Conflicting resource requirements by the application programs are detected. An application may preempt a currently executing application by claiming the hardware resources currently in use. The application from which resources have been claimed is identified so that it may be resumed when the required resources become once again available. Before the resources from a given application are claimed by another application, the user is provided a warning so that he may alter the order in which the applications are run.

Abstract: Automatic gain control (AGC) is provided in a digital signal processor environment. A predetermined threshold value, a predetermined automatic gain control value, and a predetermined count threshold value are established and stored in a data memory associated with a signal processor. Each incoming signal sample that is received is multiplied by the AGC value with the product being temporarily stored in the data memory. The absolute value of the resulting product is taken and added to the predetermined threshold value. If the result of this operation results in a signal processor overflow, then the AGC value is reduced and stored back into the data memory. The adjustment period of the AGC value is chosen to be well under the allowable distortion time for speech, dual tone multi-frequency reception, and modem operation.

Abstract: A memory array associated with a display can be accessed in either one of two substantially orthogonal directions. The memory array is structured so that it may be accessed, such as for reading or writing, in either the horizontal or vertical direction. Pel position representations in the array are arranged so that vertically sequential pel positions in a given column are represented by data in sequential memory modules rather than by data in the same memory module. Likewise, horizontally sequential pels in a given row are represented by data in sequential modules rather than in the same module. The memory array is comprised of a plurality of separate memory modules and is structured so that both x and y directional accessing into and out of the array is accomplished on a bit addressable x,y field. This enables any bit string in the array to be addressed and to be read from or written into the array in either the x or y direction.

Abstract: A method and apparatus are described for phase and frequency locking a reference oscillator to an incoming modulated signal. The method and apparatus enable the carrier recovery of the incoming modulated signal. Phase and frequency locking devices are connected in feedback loops with a coherent detector that determine the amount of phase and frequency error between the reference oscillator of the coherent detector and the incoming modulated signal. The feedback loops correct such frequency and phase error so as to enable the reference oscillator to be in phase and frequency step with the modulated signal.

Abstract: A method and apparatus are disclosed for enabling a diskette drive system to distinguish between diskettes and verify that the diskette currently in the drive is the correct one. Each diskette contains a file allocation table for controlling the allocation and deallocation of storage space on the diskette. Each time that the file allocation table on a diskette is accessed, i.e., read or written, a cyclic redundancy check (CRC) value for the file allocation table is calculated and stored. When checking the validity of a diskette, i.e., that the correct diskette is in the drive, a CRC value for the file allocation table of the currently loaded diskette is calculated and compared to the most recently stored CRC value. If the most recently calculated CRC value does not match the most recently stored CRC value, then this is an indication that the wrong diskette is currently in the diskette drive. A warning is then provided to the system user to change diskettes before a read or a write operation will be commenced.

Abstract: A "lookback" carry function is implemented in a binary incrementor. In contrast to conventional lookahead carry functions, the present "lookback" carry function implements an actual carry during the incrementing operation. After the carry function has been implemented at each register position, a subsequent determination is made as to whether each carry function was a valid one and should have been carried out. With respect to any carry functions which were not valid, subsequent circuitry will eliminate such carries to leave the appropriate carry pattern in each position of the register. In order for a carry to be considered valid, the incrementation of all bits of a lower order must have resulted in a carryout.

Abstract: A filter suppresses energy at time varying or ensemble varying frequencies. The filter comprises multiplier sections having sets of values which are dynamically varied during the receipt of time varying or ensemble varying energy. The variation of the values of the multiplier sections provides the suppression of energy at the time varying or ensemble varying frequencies. The sets of values for the multiplier sections are chosen such that the poles of such values lie within the unit circle of the z-plane locus. The location of the poles within the unit circle guarantees that the filter remain stable even though the multipliers may be located in a feedback path. In the preferred embodiment, the dynamically varying filter is used in a dual tone multi-frequency (DTMF) receiver.

Abstract: A cartridge (1) is attached to a carrier and tiltable around a tilting axis (2). The carrier is movable along platen (3) and parallel to the print line and tilting axis (2). On the rear and on the bottom of the cartridge a drive knob (4) is provided as part of the internal cartridge ribbon drive. On the carrier a ribbon feed device with wheel (6) and upright standing blades (7) is provided. Those blades (7) cooperate with walls (9) inside the knob surface and form a kind of screw driver interconnection. Both engaging parts (7) and walls (9) allow a movement perpendicular to their rotational axis and to each other. Wheel (6) with blades (7) rotates around an axis (11) and knob (4) rotates around axis (12). Intentionally the two rotational axes (11, 12) are offset to each other relative to tilting axis (2). Thus, always a moment around this tilting axis (2) is created.