JPS60127571A - Floppy disk device - Google Patents

Abstract

PURPOSE:To prevent occurrence of out of synchronism at the time of reproduction by preparing a clock for synchronizing utilizing data for identification related to a track sector written in a floppy disk and performing writing basing on this clock. CONSTITUTION:A separate clock 7 is separated by a data clock seperator 2 from first-hand data 5 read out from a disk by floppy disk drive 1. The clock 7 is compared with an output of a digital divider 15 by a phase comparator 11, and the output frequency of a digital multiplier 14 is controlled by the output. The oscillation frequency of a PLL circuit consisting of a phase comparator 13, a multiplier 14 and a divider 15 is pulled in the separate clock 7 and synchronized. That is, a write signal 9 synchronized with a synchronizing signal is obtained. By inputting the write signal 9 to a floppy disk controller 3, write data 8 synchronized with the synchronizing signal of raw data 5 read out from the floppy disk can be outputted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a floppy disk device that performs synchronization during writing to enable stable playback at all times.

[Background of the invention]

FIG. 1 is a block diagram of an example of a conventional floppy disk device. In the figure, l is a floppy disk drive, 2 is a data/clock separator, 3 is a floppy disk controller, 4 is a clock circuit, 5 is raw data read from the floppy disk, 6 is a separate data drive, and 7 is a separate A clock, 8 is write data, and 9 is a write clock.

From the raw data 5 read from the floppy disk by the floppy disk drive 1, a separate clock 7 necessary for the floppy disk controller 3 to reproduce the data is separated by the data/clock separator 2 and input to the floppy disk controller 3. data is obtained. In addition, the floppy disk controller 3 receives the write data of 0.7 output from the clock circuit 4.
The write data 8 is output based on the data 9 and recorded on the magnetic recording medium floppy disk by the floppy disk drive 1. Therefore, the successive data and the written data are not particularly synchronized.

That is, in a conventional floppy disk device, when writing, first, identification data regarding trunks and sectors recorded in advance on the floppy disk is read, and the data is written to a desired location. However, when writing the write data 8, Writing is performed based on the write clock generated from the clock circuit built into the device, and the data is written based on the write clock generated from the clock circuit built into the device. There is no special synchronization with the identification data (its clock).

Therefore, even when writing to a floppy disk recorded on another device that is of the same format and is compatible, the clock frequency at the time of writing of the data that has already been written and the clock frequency of the writing of the newly written data are the same. There are cases where the data write clock frequency is different from the data write clock frequency, and there is a problem that the data/clock separator 2 may not be able to follow the data during reproduction, and the data may not be reproduced correctly.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a floppy disk device that does not have the problems of the conventional floppy disk devices described above and can always reproduce data stably.

[Summary of the invention]

In order to achieve the above object, in the present invention, when writing data to a floppy disk, in order to confirm the writing location, the clock is separated from the identification data regarding trunks and sectors successively output from the disk. An oscillation circuit that oscillates in synchronization with a separated clock is provided, and writing is performed based on the clock generated by this oscillation circuit.

In other words, when attempting to write a new data, a synchronization clock is created using the identification data related to the trunk sector already stored on the floppy disk, and the data is written based on this synchronization clock. Therefore, by using the floppy disk device according to the present invention, it is possible to completely prevent out-of-synchronization during playback.

[Embodiment of the Invention] FIG. 2 is a diagram showing an embodiment of the present invention, in which numerals 1 to 9 indicate the same things as in FIG. 1, 10 is a gap (GAP) detector, and 11 is a sink (SYNC). Detector, 12 is an AND gate, 13 is a phase comparator, 14 is a digital multiplier, 15 is a digital device!゛, 16 is FDc-R
G double signal floppy disk controller/read gate signal Floppy Disk Controller
-Read Gate Signal (signal indicating a state in which the floppy disk controller performs a continuous read operation based on the sink), 17 is a gap detection signal, 1
8 is a sync detection signal.

From the raw data 5 read out from the floppy disk drive 1, the gap detector 1o outputs a gear detection signal 17, and the sync detector 11 outputs a sync detection signal 18, both of which are sent to a phase comparator 13 via an AND gate 12. is input. Phase comparator 13, digital multiplier 1
4. Digital divider 15 is P L L (Phas
e Locked Loop). The separate clock 7 separated by the data/clock separator 2 from the raw data 5 successively output from the floppy disk in the floppy disk drive 1 is compared with the output of the digital divider 15 by the phase comparator 13. Digital multiplier 14 by output
The output frequency of is controlled. This comparison by the phase comparator 13 is performed from the floppy disk controller 3 to the FDC.
-RG signal 16 is output and AND gate 1
This is performed during a period when a second signal (an enable ENA signal in FIG. 3, which will be described later) is being output, and the oscillation frequency of the PLL circuit is pulled in and synchronized with the frequency of the separate clock 7. During the other period □, the PLL is locked in this pulled-in state. FIG. 3 shows, from the top, signals read from the floppy disk, namely raw data 5, gap detection signal 17, and sync detection signal 18.
, FDC-RG signal 16, and ENABLE signal. That is, a write signal 9 synchronized with the sync signal in the E N A B L E signal section is obtained. By inputting this write signal 9 to the Fronby disk controller 3, it is possible to output write data 8 synchronized with the sync signal of the raw data 5 read from the floppy disk.

〔Effect of the invention〕

As explained above, according to the present invention, at the time of writing, synchronization is performed with the identification data regarding trunks and sectors written in advance on the floppy disk, so that playback data can always be played back stably. Therefore, data maintenance can be improved and reliability can be improved.

[Brief explanation of the drawing]

Figure 1 is a block diagram of a conventional floppy disk device.
FIG. 2 is a block diagram of an embodiment of the present invention, and FIG. 3 is a time chart of each signal. ■ - Floppy disk drive, 2 - Data/clock separator, 3 - Floppy disk controller, 5 - Raw data, 6 - Separate data, 7 - Separate clock, 8 - Write data, 9 - Write clock, 10-Gap detector, 11-Sink detector, 13-Phase comparator, 14-Digital multiplier, 15-Digital divider, 16-FDC/R
'G signal, 17-gap detection signal, 18-・sync detection signal.

Claims (1)

[Claims] When writing data to a rotating disk, which is a magnetic recording medium, an oscillation circuit is provided that oscillates in synchronization with a clock that is separated from identification data regarding tracks and sectors read from the disk. A floppy disk device characterized in that writing is performed in synchronization with a clock.