Abstract: An apparatus for reproducing digital signals recorded on a disk having first and second recording surfaces. The digital signals are in the form of a data frame including a lead-in block and n data blocks. The lead-in block has a same format as the n data blocks. n block addresses are assigned to the n data blocks. Information identifying an area on the disk in which the n data blocks is recorded is assigned to the n data blocks. m data blocks (0<m<n) are recorded on the first recording surface, and remaining (n−m) data blocks are recorded on the second recording surface. The lead-in block is recorded at the head of the data frame, and includes information identifying an area on the disk in which the lead-in block is recorded, a number of recording surfaces, the block address of one of the m data blocks recorded last on the first recording surface, and the block address of a last one of the n data blocks in the data frame.

Abstract: A storage library includes a first robotic mechanism having an energy coupler and a second robotic mechanism having an energy coupler. The storage library further includes tracks disposed adjacent to media object storage cells for enabling access to each of the media object storage cells, and powered rails associated with the tracks for providing energy. The first robotic mechanism is movable toward the second robotic mechanism to enable the energy coupler of the first robotic mechanism to couple with the energy coupler of the second robotic mechanism to transfer energy from the first robotic mechanism to the second robotic mechanism. The energy couplers of the first and second robotic mechanisms couple together to transfer energy from the powered rails to the second robotic mechanism. The energy couplers of the first and second robotic mechanisms couple together to transfer energy between on-board energy sources.

Abstract: An optical disk reproducing apparatus for reproducing digital signals in the form of a data frame including a lead-in block and data blocks from an optical disk including at least first and second recording surfaces each being readable from a same side of the optical disk. The data blocks include block addresses and data, and are recorded on the first and second recording surfaces. The lead-in block is recorded at a head of the data frame and includes disk information relating to a number of data blocks recorded on the first and second recording surfaces.

Abstract: Servo errors can be avoided in a bi-directional reel-to-reel tape transport in which magnetic tape is moved in either of two opposite directions for data recording by providing a fine-line tachometer for each reel and a directly coupled tension sensor. Control of tape speed is implemented in a servo algorithm that uses tachometer inputs to determine parameter values for generating reel motor drive currents. If the linear velocity of both reels is the same then the tension output must be within a tolerable range. The directly coupled tension output provided an is indication of the actual current of the tension sensor. The difference between the linear velocities of the tape from each reel is calculated and monitored together with the tape tension. A trip level is set when an error occurs to stop tape motion and permit recovery without damaging the tape.

Abstract: A library for storing a cartridge of data-storage media includes a removable module and a chassis having a module receptacle. Cartridge storage slots arc disposed within the chassis, and a media drive is disposed within the removable module. A cartridge transporter is disposed within the chassis and transports the cartridge between one of the cartridge slots and the media drive when the module is inserted within the module receptacle. A library control circuit is disposed within the chassis and controls the cartridge transporter. An interface circuit is disposed within the removable module and electronically interfaces a host computer to the media drive, and, when the removable module is inserted within the module receptacle of the chassis, electronically interfaces the host computer to the library control circuit.

Abstract: In a floppy disk drive having a main frame in which a floppy disk is inserted and a DD motor for rotatably driving the floppy disk inserted in the main frame, the floppy disk drive has a motor frame for mounting the DD motor thereon that is constituted by one piece integrated by the main frame. Preferably, the motor frame part may have a drawn-shape obtained by drawing the main frame. In addition, the floppy disk drive has an electronic processing arrangement for a frequency generation pattern. The electronic processing arrangement gives play to a function equivalent to the frequency generation pattern required to control the DD motor.

Abstract: A method of reproducing digital signals recorded on a disk having first and second recording surfaces. The digital signals are in the form of a data frame including a lead-in block and n data blocks. The lead-in block has a same format as the n data blocks. n block addresses are assigned to the n data blocks. Information identifying an area on the disk in which the n data blocks is recorded is assigned to the n data blocks. m data blocks (0<m<n) are recorded on the first recording surface, and remaining (n−m) data blocks are recorded on the second recording surface. The lead-in block is recorded at the head of the data frame, and includes recording area identifying information identifying an area on the disk in which the lead-in block is recorded, and disk information identifying (1) a number of recording surfaces, (2) the block address of one of the m data blocks recorded last on the first recording surface, and (3) the block address of a last one of the n data blocks in the data frame.

Abstract: A tape cartridge assembly contains a spool of magnetic tape with a leader block on one end. The leader block inserts into take-up reel and the tape is initially wound at a higher than normal tension to create a small band of tightly wound tape on the reel. The band eliminates the effect of any mechanical distortion created by the leader block. The remainder of the tape is wound on top of the tight band at normal tension to form an outer band of distortion-free magnetic tape.

Abstract: A method of data transfer in a cache system comprising a cache buffer including a plurality of data blocks for storing data, and a cache manager for retrieving data from a disk drive and storing the data into the cache buffer. The disk drive includes a data disk having a plurality of concentric data tracks thereon, a spindle motor for rotating the data disk, and a transducer supported by a carrier for positioning the transducer over individual data tracks to write data thereto or read data therefrom.

Abstract: A tape tension control apparatus for controlling tape tension by supplying a current to a reel motor for driving a reel in accordance with a diameter of a tape roll includes a rotational speed detector for detecting the rotational speed of the tape roll a; rotational speed comparator for comparing a rotational speed detected by the rotational speed detector and a standard rotational speed corresponding to the diameter of the tape roll; and a current corrector for correcting the value of the current supplied to the reel motor in accordance with a comparison result from the rotational speed comparator in such a manner that the speed of rotation of the reel motor becomes equal to the standard rotational speed.

Abstract: A data storage system for use with a tape cartridge storing data in a serpentine pattern on tape media, and having a memory device for storing a device block map for the tape median, comprises tape drive, or a loading mechanism, which first positions the tape cartridge at memory interface for transfering the device block map from the memory device to a processor, and subsequently positions the tape media for reading and/or writing. The processor processes the device block map from the memory device for optimal retrieval of the serpentine pattern data of the tape media. The processing of the device block map occurs while the tape media is positioned for reading and/or writing, so that the processor begins the retrieval reading process immediately upon the positioning of the tape media. In another aspect of the invention, a robotic accessor of an automated data storage library moves the tape cartridge to the tape drive.

Abstract: A magnetic recording and reproducing apparatus has a supply reel and a take-up reel around which a magnetic tape is to be wound. A first tape guide is provided in the vicinity of a rotary head at the supply reel side and a second tape guide in the vicinity of the rotary head at the take-up reel side. The first and second tape guides are movable in directions of a width of the magnetic tape. A detector detects a height of each of the first and second tape guides. A count value corresponding to the detected height of at least either the first or the second tape guide is obtained by a counter. The height of at least either the first or the second tape guide is adjusted so that the count value becomes equal to a reference value. The count value is set to a specific value when the detected height becomes a reference height corresponding to the reference value after the magnetic tape has been wound around the supply and take-up reels.

Abstract: A spindle synchronization technique is described which is useful in a disk array subsystem comprising a plurality of disk drives (40,41,42,43) connected by means of serial links (25,26,27,28) to a disk drive controller (20). Data and command information is transmitted over the link in the form of multi-character frames, the flow of which is regulated by special ten bit protocol characters. A SYNC protocol character is defined which is used to synchronize the spindles of the disk drives. This SYNC character is issued by controller to selected ones of the drives over the same link used for the transmission of the command and data information. The SYNC character may be interleaved between the characters of frames being transmitted over the link.

Abstract: A magnetic recording or reproducing apparatus having a rotary drum includes a sensor for detecting dew condensation on the rotary drum, a take-up reel for taking up a recording medium, and a controller for controlling the rotary drum and the take-up reel in accordance with a result of detection provided by the sensor. When dew condensation has been detected by the sensor, the controller causes the rotary drum to rotate in such a way as to release the recording medium from a state of sticking to the rotary drum and, after that, causes the recording medium to be taken up by the take-up reel.

Abstract: A plurality of terminals are connected to a common data bus. Each terminal is capable of issuing and processing two types of commands: a simultaneous command and a non-simultaneous command. A receiving terminal processes every simultaneous command, but processes only the most recently received non-simultaneous command. The receiving terminal acknowledges the receipt of every received simultaneous command and of every executed non-simultaneous command. The receiving terminal sends a reject signal for every received non-simultaneous signal that was not executed.

Abstract: A recording medium cartridge has a bar code label provided on the outer surface of its case so that the bar code of the bar code label indicates identification information associated the with recording medium disposed in the case. A memory circuit is provided inside the case so that identification information identical to the information indicated by the bar code label may be stored in the memory circuit. A recording/reproducing apparatus includes a bar code reader for reading the bar code of the bar code label, and a memory reader for reading the identification information stored in the memory circuit. Either the identification information read by the bar code reader or the identification information read by the memory reader is employed as the identification information associated with the recording medium cartridge.

Abstract: A reading device for reading identification information of cartridges comprises a judging circuit for judging whether the cartridge has an identification information storer for storing the identification information of a recording medium thereof, and an information reader for reading the identification information of the identification information storer. This judgment is made before the information reader reads the identification information of the identification information storer, and the information reader reads the identification information only in the event that the cartridge has an identification information storer. Accordingly, waste of time and labor are spared for reading the identification information, and trouble such as deterioration and damage from to attempting to read the identification information from storage medium cartridges which do not have the identification information storers can be prevented.

Abstract: A tape system that uses a Kalman filter to produce both an estimate of the tape pack radius and an estimate of the associated estimation error variance. The Kalman filter produces the estimates based on current and prior angular estimation position measurements of the reel, capstan, and tension arm, and the prior estimates of both the tape pack radius and the estimation error variance. The filter gain is based on prior estimation error variance and a calculated measurement error variance, which is a function of the current and prior measurements. Preferably, the system uses two Kalman filters, one to produce the estimates for the supply reel and one to produce the estimates for the take-up reel.

Abstract: A disk drive constructed according to an exemplary embodiment of the present invention includes a disk having a plurality of tracks formed concentrically along a first surface of the disk for storing data. The tracks are divided into first and second data storage regions positioned between an innermost circumferential region and an outermost circumferential region of the disk. First and second heads write and read data to and from the first surface of the disk. The first head is positioned to access the first data storage region while the second head is positioned to access the second data storage region, and the first head being positioned to access the second data storage region while the second head is positioned to access the first data storage region. First and second arm assemblies are respectively connected to the first and second heads. The first arm assembly extends the first head over a first radius of the disk, and the second arm assembly extends the second head over a second radius of the disk.

Abstract: A hard disk drive rapidly shakes a voice coil motor to remove a stiction error caused by a friction force between a head and a disk. A start-up oscillator generates a spindle motor rotation control frequency according to a level of a spindle motor driving control voltage and controls a rotation of a spindle motor according to the spindle motor rotation control frequency. A restart oscillator generates a restart control signal for controlling the level of the spindle motor driving control voltage to restart the rotation of the spindle motor. A resistor is interposed between the restart oscillator and ground, to allow the restart control signal to control the level of the spindle motor driving control voltage, so as to prevent the spindle motor from being restarted. A microcontroller monitors the level of the spindle motor driving control voltage to detect a stiction error and provide a voice coil with a voice coil shaking control signal upon a detection of the stiction error.

Abstract: A web motion control system for controlling the tension in a web advanced at a preset velocity in a web transport path between a supply reel and a take-up reel without the use of tension loops, particularly for use in transporting spliced together, developed filmstrips through a film preparation work station. The web (film) is advanced in the web transport path in either a forward or rewind direction in either a velocity mode or a position mode by a motor driven capstan roller. The supply and take-up reels have a hub over which the web is wound in unknown supply and take-up web winding diameters. Take-up and supply reel motors and encoders are attached to the take-up and supply reels for imparting torques to the reels in response to motor torque signals to prevent slack in the film segments between the reels and the capstan roller and to provide reel encoder output signals on at least each 360.degree. rotation of the reels.

Abstract: A disk storage device in which two or more discrete disk velocities are used is disclosed. The disk velocity is selected using operating environmental conditions. Various types of sensors may be used to detect the environmental conditions or the environmental conditions may be input by a user. The allocation of track locations on a disk into zones reduces the number of zone bit frequencies the storage device must handle when multiple frequency zones are used in connection with the various spindle speeds.

Abstract: In a disk protection method for protecting a magnetic recording disk upon ejection thereof from a removable magnetic recording/reproducing device by an eject mechanism through operation of an eject button, data writing relative to the magnetic recording disk is inhibited in response to a data write inhibit signal which is generated immediately after the operation of the eject button and before the eject mechanism actually starts the ejection of the magnetic recording disk. The eject mechanism actually ejects the magnetic recording disk from the removable magnetic recording/reproducing device in a condition where the data writing is inhibited.

Abstract: Disclosed are a method and apparatus for detecting disk drive start-up failure under disparate temperature conditions by employing a temperature sensor to measure the temperature of the disk drive at start-up. A controller selects, in response to the measured temperature, a start-up failure timing corresponding to that measured temperature. The controller then detects whether the disk drive reaches operational speed within the selected start-up failure timing. Preferably, the temperature sensor is digital. The temperature sensor may be mounted on the drive electronics card, or on electronics in the disk enclosure. The controller may have a stored lookup table relating various temperatures to start-up failure timings for selecting a start-up failure timing corresponding to the measured temperature. This method allows selection of a motor torque constant that does not compromise normal operating performance based on cold start conditions.

Abstract: A method and apparatus is disclosed for predicting capstan slipping in belt-driven tape cartridges. The method predicts the occurrence of capstan slip conditions between the belt capstan of a belt-driven tape cartridge and the rotating elastomeric drive roller of the tape drive. To predict capstan slip conditions, the method determines a critical velocity value corresponding to a critical slip condition based on a relationship between the drive force which rotates the cartridge belt capstan, and on the normal force of the drive roller against the cartridge belt capstan. A threshold velocity value corresponding to the drive and normal forces is selected at a point where the relationship between the drive and normal forces would not yet encounter the critical slip condition. The steady-state tape velocity is monitored during operation of the tape cartridge in the tape drive, and an imminent capstan slip indication is provided when the steady-state tape velocity reaches the threshold velocity value.

Abstract: An autochanger incorporates a storage unit that includes a plurality of storage sections for storing recording medium cartridges. The recording medium cartridges have a recording medium installed, and a first memory for storing data informative of the recording medium. Connection terminals allocated to the storage sections are provided for accessing the first memory of a desired recording medium cartridge. A loading/unloading unit is provided for loading and unloading the cartridges, and accessing a data signal on the recording medium of the cartridges. A carrier conveys the recording medium cartridges between the storage unit and the loading/unloading unit, and a control memory saves the informative data.

Abstract: A method of controlling automatic state returns relates to a dynamic system coupled to an automatic control operating in a discrete negative feedback mode. The method includes a phase for defining a controller, and a phase for operating the system. The defining phase is realized in an open-loop learning phase which includes a step of reading states in which a system may be situated, and a step of generating commands for returning the system to an ideal state. When the commands generating step takes place, the method supplies, for each state, a sequence of discrete commands which are determined by imposing a constraint intended to reduce the error relative to that state below a predetermined threshold.

Abstract: In a storage disk control apparatus, a load of a computer caused by transferring data is reduced, and a waiting time until a data transfer operation is commenced is shortened. In the disk control method for controlling a disk apparatus including a disk having a plurality of storage regions for storing data therein by way of an external apparatus external addresses produced from the external apparatus are related to internal addresses indicative of positions of the storage regions the external addresses are converted into the internal addresses related thereto, and the disk is accessed based on the internal addresses.

Abstract: An automated library is disclosed for storing and retrieving data storage cartridges having a plurality of rotatable stacks, all rotatable about parallel axes, each stack being multi-faced and preferably rectangular. A column of cells for storing data cartridges is provided in each of at least two of the faces of the rectangular stacks, and the columns of cells are aligned parallel to the axis of the associated stack. At least one read/write drive is provided for reading and/or writing the data storage cartridges, and preferably a read/write drive is provided at the base of each rotatable stack. A picker is rotatable about an axis parallel to the axes of the rotatable stacks, for accessing the data storage cartridges stored in the cells, and for transporting the cartridges between the cells and a read/write drive. Servo systems rotate the rotatable stacks and the rotatable picker into mutually facing positions for accessing the cells of columns of the stacks with the rotatable picker.

Abstract: A tape drive writes/reads tapes written in a format which stores an increased amount of data because the tracks overlap. The wide write/narrow read heads read a center portion of each track which does not have overlap. The new format is identified by the positions of a reference burst, by encryption of the bad sector map, and by alteration of the tape signature to prevent unqualified drives and software from operating upon tapes in the new format.

Abstract: A cartridge for a data storage disk drive has a thin retroreflective marker. Light from a source is reflected from the marker almost exactly on its incident path. A planar light shaping optical structure such as a holographic light shaping diffuser (LSD) ruled or blazed diffraction grating, holographic diffraction grating, binary optics or holographic diffraction grating directs light to the detector. The LSD has degrees of angular diffusion in different orthogonal axes. This property makes possible unique identification of different types of cartridges.

Abstract: A method of recording digital signals on a disk which has at least a first recording surface and a second recording surface both being readable from a same side of the disk. The digital signals are in the form of a data frame which includes at least n data blocks (n is a natural number).

Abstract: A computer network includes a network server in communication with a plurality of user terminals. The network server includes disk drives which store data accessible via the user terminals. To increase power efficiency of the network server, the number of accesses to the disk drives is monitored and a histogram is generated to display the distribution of disk accesses over time. A network administrator subsequently selects time intervals to spin down one or more of the disk drives during periods of disk inactivity as depicted in the histogram. In a preferred embodiment, the network administrator uses the histogram for failure analysis to determine which disks are more likely to fail over long time periods.

Abstract: A rewind tape drive is disclosed for a tape library for rewinding a tape upon a read/write tape drive of the library completing reading and/or writing a tape. In some instances, the tape may be positioned close to the beginning of tape at the completion of reading and/or writing. Thus, the disclosed invention may additionally, upon completion of reading and/or writing a tape, determine whether the time required for the tape drive to rewind the tape exceeds a predetermined time, and transport the tape to the rewind unit only upon exceeding the predetermined time. The predetermined time may comprise the time required for unloading the tape from the read/write tape drive to an accessor, the time required for the accessor to transport the tape to the rewind unit, and the time required to load the transported tape into the rewind unit.

Abstract: Write splicing for a helical scan tape drive (30) involves, upon occurrence of a predetermined condition such as a buffer low condition, recording an indication of a tape transport transition (ITTT) on tape (31) and then recording dummy helical stripes (DSd1-DSdn) having deviant form as the magnetic tape is decelerated to a stop. After the predetermined condition is overcome, further deviant, dummy stripes (DSa1-DSan) are recorded as the tape is accelerated back to nominal tape transport speed. At the nominal tape transport speed, non-deviant stripes (S2) containing user data are again recorded on tape. A distance separating a first set of stripes ?S1! (recorded prior to the occurrence of the predetermined condition) and a second set of stripes ?S2! (recorded upon again attaining the nominal tape transport speed) is an integer multiple of the track pitch (P) of a non-deviant stripe. The write splice is thus performed without reversing the direction of tape transport.

Abstract: A mechanical and finishing and/or signal processing apparatus for tapes, in particular magnetic tapes, includes at least two tape transporting devices, which apply an average tape tension of 2 N per inch (25.4 mm) of tape width and consequently remain below about 20% of the maximum tensile force of the tape material, to avoid permanent material deformations. The processing devices may be smoothing, abrading, polishing and cleaning devices and also signal recording/reproducing devices and/or signal or tape quality control devices.

Abstract: Disclosed herein is a magnetic tape drive unit including a write circuit for writing data onto a magnetic tape, a read circuit for reading data written on the magnetic tape, a cartridge load circuit for controlling a load operation that a magnetic tape cartridge put into the drive unit is moved to a position where a hub of the cartridge is rotatable, and also controlling an unload operation reverse to the load operation, and a tape thread circuit for controlling a thread operation that the magnetic tape is drawn from the cartridge loaded and is then wound around a machine reel, and also controlling an unthread operation reverse to the thread operation. The magnetic tape drive unit further includes a power supply for supplying power to each circuit. An operating condition of each circuit is monitored and the supply of power from the power supply to each circuit is individually switched on or off by a control circuit, thereby allowing power saving.

Abstract: A magnetic recording and reproducing apparatus for recording a desired sound or picture signal to a magnetic tape by a magnetic head. At the time of normal-speed recording and reproduction, the magnetic tape is taken up at a constant speed, but by changing the tape travelling speed of the tape on the rotary drum, DTF control and high-speed noiseless reproduction are enabled. The tension of the tape on the entrance side of the rotary drum is controlled to a desired value. This apparatus includes a tape tension actuator and a tape drawing actuator on the entrance side and on the exit side, respectively, of the rotary drum. In DTF control, both tape actuators correct a tracking error of the tape in cooperation with each other. In high-speed noiseless reproduction, both tape actuators are differentially driven so as to lower the tape travelling speed on the rotary drum. Both tape actuators are driven in feedback control using the modern control.

Abstract: A relative-position measuring system of a recording-medium library apparatus including first to third reference flags installed for measuring the magnitude of the gradient of an accessor and a plurality of relative-position flags provided at a cell drum. A flag sensor for detecting the first to third reference flags is installed on a hand mechanism of the accessor for finding the gradients of the accessor with respect to Y and Z axes. The gradients of the accessor with respect to Y and Z axes are used for correcting design tachometer count values of the relative-position flags to give theoretical tachometer count values which are stored in a memory unit. When the accessor is moved, the relative-position flags are sensed by the flag sensor. Actual tachometer count values which are actually obtained when the relative-position flags are detected by the flag sensor are also stored in the memory unit.

Abstract: A tension lever is pivoted to a chassis at one side of a reel support and has attached thereto in the vicinity of the pivoted portion opposite ends of a tension band reeved around the reel support. First and second two tension springs are provided between and fitted to a control lever and the tension lever each pivoted to the chassis and rotatable to different positions for different tape running modes. The second tension spring is fitted to the control lever with play in the direction of stretch of the spring. For reverse playback, the control lever rotates within the limits of play of the second spring to stretch the first spring only. The control lever stretches both the two springs for usual playback.

Abstract: A media stackloader processes removable data storage media such as optical disks, magnetic diskettes, or tape media. The stackloader removably couples to a storage drive, such as by plugging into a slot of the host computer. The stackloader has a plug portion integral with a housing portion, the plug portion plugging into the host computer and the housing portion housing a magazine containing the removable media. The stackloader includes a device for moving the magazine vertically within the housing to align selected cartridges with an opening in one of the drives of the personal computer. After the cartridge is aligned, a device is employed for moving the cartridge horizontally into the drive for processing and, after processing, for withdrawing the cartridge from the drive back into the magazine. A locking mechanism selectively locks and unlocks the cartridges to prevent improper removal of cartridges from the magazine.

Abstract: A tracking control circuit is disclosed for use in a digital image recording and reproducing device which has a mechanism (22) for controlling the movement of a magnetic medium according to a servo control signal, which has an error correction code decoder (12), and which reproduces data recorded on the recording medium in sync blocks. The tracking control circuit includes a bit error rate detector (14), a control unit (16, 18) and a servo circuit (20). The bit error rate detector (14) calculates the frequency of bit errors in the reproduced data by counting the number of error flags from the error correction code decoder in each sync block to thereby producing bit error rate data. The control unit (16, 18) generates tracking control data corresponding to bit error rate data generated by the bit error rate detector (14) when the bit error rate data from the bit error rate detector exceeds a predetermined limit.

Abstract: A tape tension control apparatus for controlling a tension of a tape extended between a pair of reels including a current servo system for adjusting a current of a reel motor in accordance with a diameter of a tape roll wound on a reel, a speed servo system for adjusting a current of the motor so that the rotational speed of the motor exceeds a predetermined value corresponding to the roll diameter, and a changeover device for selecting between said servo systems. The changeover device selects the speed servo system upon activation of the apparatus, after which it selects the current servo system when the current to the motor exceeds a predetermined value.

Abstract: A magnetic recorder and/or a regenerator which deletes a troublesome key operation at the time of regeneration and improve operability is provided. A play key operation detecting means which detects that the play key is on in a power-off state and outputs a detecting signal and a play operation practical means which practices the play operation together with supplying the power to the indicator portion, tape deck, servo circuit and the video-audio circuit based upon the detecting signal outputted from the play key detecting means.

Abstract: In a housing for removable computer mass-storage drives, commands coming in over a computer bus direct a removable mass-storage drive to spin down. Electronics in the housing detects that a removable mass-storage drive has begun to spin down by sensing the amount of current it is using. Following a delay period which is set by jumpers on the removable mass-storage drive itself, to allow for spin down to complete, the housing actuates a latch which releases the removable mass-storage drive and allows the user to remove it.

Abstract: a An apparatus for preventing damage to components of a hard disk drive having a microprocessor when the microprocessor fails. The hard disk drive further includes at least one read/write head and a data storage disk having a designated parking zone. The apparatus includes a microprocessor monitoring circuit configured to be coupled to the microprocessor. The microprocessor monitoring circuit is configured for detecting a microprocessor failure condition in the microprocessor. The apparatus further includes a head park circuit coupled to the microprocessor monitoring circuit. The head park circuit is configured to receive a park command from the microprocessor monitoring circuit when the microprocessor failure condition is detected by the microprocessor monitoring circuit.

Abstract: A video cassette recorder comprises a pair of pole base assemblies each of which includes a guide roller for guiding a running magnetic tape to help maintain a proper contact with a head drum having at least one video head, a base and a post for supporting the guide roller, and a lever for selectively vertically moving the posts depending on operation modes. The post is mounted to the base and movable vertically, and the guide roller is rotatably fixed to top of the post. The lever is provided with a pair of stepped portions, is mounted under a deck, and horizontally moves depending on the operation modes so that the stepped portions selectively contact and move the posts by a desired height to tilt the tape between the guide rollers at an angle, thereby allowing the video head of the head drum to correctly read tracks recorded on the magnetic tape.

Abstract: A method of and a device for determining the total playing time of a magnetic tape accommodated in a cassette (1) in a magnetic-tape recording and/or reproducing apparatus, for example, a video recorder of the helical-scan type. The tape (4) is moved between a tape spool coupled to a first reel disc (2) and a tape spool coupled to a second reel disc (3), two measurements being carried out. In the first measurement, the tape is moved with a known tape speed. The revolution times (T.sub.l, T.sub.r) of the first and the second reel disc are measured in this first measurement and a parameter is derived which corresponds to the sum of the squares of the revolution times. A cassette-specific constant (.beta.) is derived from this parameter and the known tape speed. In a second measurement, the revolution times of the first and the second reel disc are measured during N revolutions of one of the two reel discs for each revolution of this reel disc.

Abstract: An autochanger of the present invention incorporates a cartridge storage 10 which comprises a plurality of storage cells 11 for storing magnetic tape cartridges 50, each magnetic tape cartridge having, for example, a magnetic tape 52 installed in a cartridge thereof and an IC memory 51 mounted thereon and carrying an informative data of the magnetic tape 52, and a corresponding number of connection terminals 12 allocated to the storage cells 11 respectively for accessing the IC memory 51 of a desired magnetic tape cartridge 50.

Abstract: A recording and/or reproducing apparatus which includes no pinch roller and no capstan and wherein the converging time to a rated speed upon starting of feeding of a tape can be reduced and the tape can be fed stably at the rated speed during recording and/or reproduction of the tape. A rotary encoder for detecting a period of rotation is disposed between a recording and/or reproducing head and a take-up side reel, and a deviation from a predetermined reference value or a feeding position of the tape is calculated from the period of rotation detected by the rotary encoder.