摘要:
A magneto-optic storage media is provided with two defect information blocks for storing information concerning a defect. At the time of reproduction, both the blocks are read, and it is determined whether or not the reading operation is normal. If the reading operations of both the blocks are normal, it is determined which of the respective numbers= of registrations of the information concerning a defect stored in both the blocks is larger so that the block in which the number of registrations is larger is utilized. Then, the defect information in the block which was not employed is updated and registered with the defect information. if the defect information is not registered, the block is switch so that an updating and registering operation can be executed again.
摘要:
A recording and reproducing apparatus is provided which includes a recording condition control device for controlling recording conditions during recording of a binary-coded original recording signal on a recording medium, a signal recording device for recording the original recording signal onto the recording medium according to recording conditions set by the recording condition control device, a reproducing signal output device for outputting binary-coded reproducing signals by detecting the recording signal as recorded on the recording medium by the signal recording device, and a recording condition setting device for obtaining the recording conditions to provide a reproducing signal approximately equal to the original recording signal through a comparison between the reproducing signal outputted from the reproducing signal output device and the original recording signal.
摘要:
A disk recording checking method in which recording is performed on a disk having radially different recording tracks each divided circumferentially into a plurality of sectors. The method employs a continuous writing device for continuously writing data onto a predetermined number of the sectors, and a continuous checking device for checking the data, while continuously reading the data from the predetermined number of the sectors. The method utilized checks both the number of errors in each code sequence and the total number of errors in each sector to determine if the data in the sector is valid.
摘要:
A disk recording method in which recording is performed on a disklike recording medium having a radially coaxial or spiral recording track that is divided into a predetermined plural number of recording sectors each acting as a recording unit. A predetermined number of dedicated sectors are provided at a rear portion of the recording track so that the contents that are recorded in defective sectors of the recording sectors are alternatively assigned to the dedicated sectors.
摘要:
A test mode switching system includes a register for storing test signal data and for outputting the test signal data to a self testing circuit for checking whether or not the LSI operates correctly. A memory stores a test inhibiting signal and a test allowing signal received from a CPU through the control signal terminal of the LSI. The register is enabled to output test signals depending on the condition of the output of the memory whereby the LSI can operate either under a normal operation mode or under a test mode.
摘要:
A floppy disk drive system with a stand-by mode that shuts off power to the drive circuits that drive the head-positioning motor and the disk drive motor. The stand-by model is activated when no motor-activating signal is input within a predetermined period of time. As a result, this unique stand-by mode significantly reduces the power consumption of the floppy disk drive unit. At the same time, the stand-by mode extends the service life of several important components, such as the head-positioning pulse motor. When the stand-by mode is entered from the normal mode, the current position of the head is stored. Then when the normal mode is to be reentered from the stand-by mode, the head is first moved to a reference track and then back to the position at which the stand-by mode was entered so that the value of the two counters is equal.
摘要:
A device for controlling an access operation of an information recording and reproducing device to a target position for rough access in a disk-shaped recording medium prior to a precision access to a final target position, including a head carried by an actuator, a scale, a counter, a comparator, a timer, and a controller. The scale emits pulses while the head is traveling. The counter counts the pulses and then provide the count to the comparator, which calculates a difference between the count and an access distance to be traveled for rough access and then compares the difference with a value which is determined in advance in consideration of a tolerable error. The comparison result is input into the controller. If the comparison result received when the timer finishes measuring the specified time indicates that the difference between the access distance and the count falls within the range of the predetermined value, the controller decides that the actual rough access operation has been normally finished as desired, thereby decreasing a wrong judgement with respect to finish of the rough access irrespective of a value counted by the counter.
摘要:
A floppy disk driving circuit comprises a memory circuit for storing a plurality of items of delay time of a pair of erase heads from the switching-ON and the switching-OFF of a read/write head for all the tracks of a floppy disk, a control circuit responsive to the memory circuit for controlling ON- and OFF-delay timing of the pair of erase heads based on the plurality of items of delay timing. The plurality of items of suitable timing are previously calculated in connection with the respective tracks of the disk and stored within the memory circuit.
摘要:
A lighting device includes a plurality of self-luminous elements formed on a substrate and emitting different wavelengths of light from each other, a hemispherical lens structure formed on the substrate to cover the self-luminous elements, and a plurality of translucent spherical particles covering a surface of the lens structure. Light emitted from the self-luminous elements passes through the lens structure and enters the translucent spherical particles where its direction is largely inclined to scatter due to a difference in refractive index between the translucent spherical particles and air. Consequently, different wavelengths of light from the self-luminous elements are mixed to produce a desired color of light.
摘要:
An image processing device comprises an image data input means 2, an image data storage means 12 for storing the image data being input, an image data processing means 6 having multiple processing modes for outputting the stored image data, and a image data erasing means for erasing the image data stored in the storage means 12. The device further comprises erase count control means 8, 14 for controlling the number of times for erasing image data capable of having the number of times of erase set arbitrarily according to the security level required for each mode, and capable of having the set number of times of erase changed in mid-flow. Confidentiality is protected by performing erase operations repeatedly to the region storing the unnecessary image data according to the security level.