摘要:
A flexible magnetic disk drive is disclosed which has a stepper motor coupled to a data transducer via a steel belt motion translating mechanism for moving the transducer from track to track on the rotating disk in response to stepping pulses and a stepping direction signal from an external host system. In order to save power, the stepper motor is held deenergized while the disk drive motor is out of rotation, with the consequent possibility that the transducer may be displaced from the required track position on the disk while the stepper motor is held deenergized. Therefore, in order to always memorize the latest of the successive destination tracks commanded by the host system, a forward/backward counter is provided which counts the external stepping pulses in either direction depending upon the binary state of the external stepping direction signal. After the disk drive motor is set into rotation, stepping pulses and an stepping direction signal are generated internally for causing the stepper motor to automatically reposition the transducer on the memorized latest destination track.
摘要:
A flexible magnetic disk drive is disclosed which has a data transducer mounted to a pivotal support beam for movement into and out of data transfer contact with the disk. When the transducer is retracted away from the disk, the support beam butts on the top plate of the disk drive casing for the reduction of the thickness of the disk drive, that is, its dimension in a direction perpendicular to the plane of the disk. A stepper motor is provided for moving the transducer across data tracks on the disk in response to external stepping pulses from a host system and to internal stepping pulses for recalibration. The application of such stepping pulses to a stepper motor control circuit is prevented when the disk is not loaded in the disk drive, in order to avoid the movement of the support beam in sliding contact with the top plate.
摘要:
A floppy disk drive controller has a control part which performs a plurality of kinds of controls by means of outputting control information appropriate to each kind of control, and a memory part in which information which selects a predetermined kind of control from among the plurality of kinds of controls is pre-stored, the control part outputting the control information corresponding to the predetermined kind of control which is selected based on the information from the memory part.
摘要:
A floppy disk drive is disclosed which is for use with a host system capable of connecting its own power supply to the disk drive when its operation is needed, and disconnecting the power supply from the disk drive when its operation is not needed. The disk drive includes a stepper motor for moving a data transducer from track to track on a rotating magnetic disk, and a track counter for ascertaining the radial position of the transducer on the disk by counting the stepping pulses fed from the host system to a stepper motor control circuit. In order to maintain the count of the track counter despite power suspension, the track counter is connected to a supply terminal of the disk drive via a reverse blocking diode, and a capacitor is connected between the diode and ground. The track counter is therefore fed from the capacitor when the disk drive is disconnected from the power supply of the host system. Preferably, the count of the track counter when the disk drive is disconnected from the power supply may be temporarily stored on an electrically erasable, programmable read only memory, and the stored count may be returned to and preset on the track counter when the disk drive is subsequently powered on.
摘要:
In order to drive the stepper motor of a floppy disk drive with practically constant current in the face of fluctuations in supply voltage fed from a host system, a power control pulse generator circuit is provided which produces a series of power control pulses having a duty ratio dependent upon fluctuating supply voltage. The power control pulses are used for interrupting the excitation of the stepper motor windings during track seek operation. The power control pulses are generated by first repeatedly counting clock pulses from the host system to a predetermined number to provide periodically varying digital data, then translating the digital data into a triangular wave having an amplitude dependent upon the supply voltage, and then comparing the triangular wave with a reference voltage.
摘要:
A microcomputer system having a flexible magnetic disk drive and a controller therefor, with the disk drive including a stepper motor for incrementally moving a transducer from track to track on a rotating magnetic disk, and a clock which is inherently unstable in operation during a predefinable startup period thereof after being powered on. In order to enable the disk drive to internally generate stepping pulses for driving the stepper motor at twice as high a rate as by external stepping pulses from the controller without being affected by unstable clock pulses during the startup period of the clock, the controller supplies external stepping pulses to the disk drive after imparting a predetermined delay, longer than the startup period of the clock, to each series of external stepping pulses with respect to the moment a power save signal, also supplied from the controller to the disk drive, indicates that the clock and other power consuming parts of the disk drive be powered. Within the disk drive a counter counts the clock pulses for a length of time equal to half the period of each series of external stepping pulses in response to each incoming external stepping pulse, thereby providing output pulses that rise with the respective external stepping pulses. A pulse generator circuit generates internal stepping pulses in synchronism with both leading and trailing edges of the counter output pulses. Additional embodiments are disclosed.
摘要:
A disk drive connected to a host computer compatible with a plurality of computer hardware types can automatically transmit one desired control signal to the host computer, the desired control signal corresponding to a computer hardware type which is being used for the host computer. The disk drive may use a signal transmitted from the host computer which represents a storage capacity of a disk used for the disk drive.
摘要:
A system for infallibly positioning a transducer on Track Zero on a flexible magnetic disk in the face of possible sensing errors by an optical Track Zero sensor customarily build into a disk drive. The transducer has not been correctly recalibrated if it has been positioned, when the disk drive is powered on, on an invalid track existing, either virtually or actually, immediately radially outwardly of Track Zero and if the disk drive is connected to a host that commands recalibration merely by causing transducer travel radially outwardly of the disk. A recalibration control circuit is therefore provided which cancels the host command and which, instead, causes the transducer to travel a predetermined distance radially inwardly of the disk and then to travel radially outwardly until the Track Zero sensor indicates again that the transducer is positioned on Track Zero.
摘要:
A flexible magnetic disk drive is disclosed which operates under the control of a host system. A CMOS inverter is employed as a power saving switch, holding a file protect sensor energized only when the standard "drive select" signal from the host commands operation of the disk drive. Another CMOS inverter is provided for two disk capacity a sensors which provide signals indicative of the data storage capacity of the loaded disk cartridge. The disk capacity sensors are energized only when the drive select signal commands operation of the disk drive and when the standard "motor on" signal dictates rotation of a disk drive motor.
摘要:
A power saving system for a flexible magnetic disk drive utilizes a power save signal supplied from a host system. When the power save signal indicates that the disk drive is standing by, a power saving circuit holds unpowered desired components of the disk drive such as a disk drive motor circuit, stepper motor circuit, read/write circuit and sensor circuits. The power saving circuit is constructed to permit the transducer to be recalibrated on a reference track on the disk only when the disk drive is turned on, but to inhibit such recalibration when the power save signal indicates the end of standby, thereby avoiding waste of power.