JP2004103103A - High-speed read/write method of track in flexible disk drive unit of usb connection - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for read/write of tracks in a flexible disk drive unit of USB (universal serial bus) connection, by which data can be read or written at high speed. <P>SOLUTION: A USBFDD unit 100 is constituted of a USB controller 101, a FIFO 102, a firmware ROM 103 in which software controlling CPU 104 is written, a RAM 105, a FDC 106, and a FDD 107 connected to the FDC 106. Sector numbers of a disk located on a head is read preceding to reed/write processing and read/write of data are performed from the sector next to the sector number. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a track read / write method in a USB-connected flexible disk drive (hereinafter, referred to as a USB FDD).
[0002]
[Prior art]
A track read / write method in a conventional USB FDD device will be described with reference to a flowchart shown in FIG.
[0003]
First, the firmware of the USB FDD device issues a SEEK command to the FDC (flexible disk controller) to move the head to a target track on the disk for reading / writing (step 20).
[0004]
Next, in the case of a disk read process (step 21), the firmware issues a READ DATA command to the FDC to read data for one track from the beginning of the track (sector number 1) (step 22). .
[0005]
At the time of issuing the command, the head is not always located at the head sector, so that a rotation wait occurs until the head sector (sector number 1) comes over the head (step 23).
[0006]
When the first sector comes on the head, the FDC transfers data for one track (from sector number 1 to the last sector) from the disk to the RAM in the USB FDD device (step 24).
[0007]
In the case of a disk write process, the firmware issues a WRITE DATA command to the FDC in order to write data for one track from the head of the track (sector number 1) (step 25).
[0008]
At the time of issuing the command, the head is not necessarily located at the head sector, so that a rotation wait occurs until the head sector (sector number 1) comes over the head (step 26).
[0009]
When the first sector comes on the head, the FDC transfers data for one track (from sector number 1 to the last sector) from the RAM in the USB FDD device to the disk (step 27).
[0010]
However, according to this conventional technique, an attempt is made to read from or write to the head sector of the track, so that a rotation wait occurs until the head sector comes over the head, and a delay occurs in the read / write processing. There was a problem.
[0011]
[Problems to be solved by the invention]
Therefore, the present invention is to provide a method for reading / writing data at high speed.
[0012]
[Means for Solving the Problems]
SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and reads a sector number of a disk located on a head prior to read / write processing, and reads / writes data from a sector next to the sector number. By doing so, it is possible to avoid waiting for the rotation of the disk and to speed up the read / write.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0014]
FIG. 1 is a block diagram showing the configuration of a USB FDD device to which the present invention is applied. 100 is a USB FDD device, and 101 is a USB controller. The USB controller 101 receives serial data flowing through the USB bus 102 and stores the data in a corresponding FIFO (first-in first-out ROM) 108 according to the type of the transaction. Conversely, it transmits the FIFO data to the USB bus 102.
[0015]
Reference numeral 103 denotes a firmware ROM in which software for controlling the apparatus is written, and instructs the CPU 104 to read out the FIFO data to the RAM 105 or vice versa. Further, the firmware ROM 103 is configured to issue a command to the FDC 106 to write the data read out to the RAM 105 to a medium inserted in the FDD 107, or vice versa, as necessary.
[0016]
That is, the USB FDD device 100 receives serial data flowing through the USB bus 102, transmits the serial data to the corresponding FIFO 102 in accordance with the type of the transaction, and conversely, transmits the FIFO data to the USB bus 102. , A firmware ROM 103 in which software for controlling the CPU 104 is written, a RAM 105 and FDC 106 connected to the CPU 104, and an FDD 107 connected to the FDC 106. The firmware ROM 103 instructs the CPU 104 to transmit FIFO data. The data is read out to the RAM 105 or vice versa, and further, the data read out to the RMA 105 is issued, if necessary, to the FDC 106 and written to the medium inserted in the FDD 107. Or the reverse is performed, and the sector number of the disk located on the head is read prior to the read / write processing, and the data is read / written from the sector next to the sector number. It was made.
[0017]
FIG. 2 shows a flowchart in the case where the present apparatus performs one-track read / write processing. First, the firmware of the USB FDD apparatus issues a SEEK command to the FDC, and reads / writes the target track on the disk from which the read / write is performed. The head is moved to (step 1).
[0018]
Next, a READID command is issued, and the firmware reads the sector number (N) on the disk where the head is currently located (step 2).
[0019]
Subsequently, in the case of a disk read process (step 3), the firmware issues a READ DATA command to the FDC to read data from the next (N + 1) to the last sector number of the sector number read in step 2. (Step 4).
[0020]
Since the head is already on the target sector number, the FDC transfers data from the sector number (N + 1) to the last sector number from the disk to the RAM area of the USB FDD device without waiting for rotation (step 5).
[0021]
Further, the firmware issues a READ DATA command to the FDC to read data from the sector number <1) to the sector number (N) (step 6).
[0022]
The FDC transfers the data from the sector number (1) to the sector number (N) from the disk to the RAM area of the USB FDD device (Step 7).
[0023]
In this way, one-track read processing is completed.
[0024]
In the case of a disk write process, the firmware issues a WRITE DATA command to the FDC in order to write data from the next (N11) to the last sector number after the sector number read in step 2 ( Step 8).
[0025]
Since the head is already on the target sector number, the FDC transfers data from the sector number (N + 1) to the last sector number from the RAM area of the USB FDD device to the disk without waiting for rotation (step 9).
[0026]
Further, the firmware issues a WRITE DATA command to the FDC to write data from the sector number (1) to the sector number (N) (step 10).
[0027]
The FDC transfers the data from the sector number (1) to the sector number (N) from the RAM area of the USB FDD device to the disk (Step 7).
[0028]
Thus, the read processing of one track is completed.
[0029]
【The invention's effect】
As described above, according to the present invention, the sector number of the disk located on the head is read prior to the read / write processing, and the data is read / written from the sector number following the sector number. Therefore, there is an effect that the disk rotation wait is eliminated and the speed of the disk read / write processing is increased.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a USB FDD device to which the present invention is applied.
FIG. 2 is a flowchart of a one-track read / write process.
FIG. 3 is a processing flowchart when one track is read / written using a conventional USB FDD device.
[Explanation of symbols]
100 USB FDD device 101 USB controller 102 USB path 103 Firmware ROM
104 CPU
105 RAM
106 FDC
107 FDD
108 FIFO

Claims (1)

In a method of reading / writing a track of a flexible disk in a USB-connected flexible disk drive, a sector number of a disk located on a head is read prior to a read / write process, and data is read from a sector next to the sector number. A read / write method for a USB-connected flexible disk drive device, characterized by performing read / write.

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