KR100255187B1 - Effective data transfer device of hdd - Google Patents

Abstract

PURPOSE: An apparatus for transmitting available data of a hard disk drive is provided to prevent data read from other sectors except a target sector from being transmitted to a host computer, so as to maintain reliability. CONSTITUTION: A disk transmitter(32) transmits data read from a disk to a memory. A host transmitter(34) transmits the stored data to a host computer during an enable section of a data transmission signal. An available sector counter(36) performs a counting increase when one-sector data are transmitted to the memory from the disk transmitter(32), and performs a counting decrease when the one-sector data are transmitted to a host computer from the host transmitter(34). A minimal sector counter(38) indicates the number of minimal sectors which have to exist in the memory. If a counting value of the available sector counter(36) is bigger than a value of the minimal sector counter(38), a counter comparator(40) generates an enable data transmission signal and outputs the signal to the host transmitter(34).

Description

The effective data transfer device of the hard disk drive

FIG. 1 is a typical sector format employed in a hard disk drive; FIG.

FIG. 2 is a block diagram of a conventional hard disk drive; FIG.

FIG. 3 is a block diagram of an effective data transmission apparatus according to the present invention; FIG.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a read data transfer method for a hard disk drive employing a headerless servo writing method, and more particularly, to an apparatus capable of transferring only data read from a target sector.

The basic sector format of a hard disk drive, which is widely used as an auxiliary storage device of a computer system, is as shown in FIG.

FIG. 1 illustrates a conventional sector format used in a hard disk drive. FIG. 1 (A) shows a servo sector in which a servo field and a data field are alternately arranged to form one servo sector (B) shows a sector format diagram of a headerless servo recording method widely used by a hard disk drive manufacturer for data field extension. In a hard disk drive employing a headerless servo recording method, since there is no ID section in which address information of a corresponding sector is recorded in each data field on the disk, special care is required when reading / writing data on a target sector do.

When a data read command is received from a host computer, a typical hard disk drive reads data from the disk and transmits it to the host computer. Such a data transfer operation is automatically performed by the hardware logic circuit of the disk data controller. That is, when one sector of data is read from the disk, the disk data controller detects the data and automatically transfers the read data to the host computer. However, in a hard disk drive employing the headerless servo method, when reading data that is written in a predetermined sector, data is read without confirming the ID, so that data may be read from a sector other than the target sector. In this case, the data written on the target sector is read again through data read retry. However, in the disk data controller constituting the conventional hard disk drive, there is a problem that even the data read from the sector other than the target sector is transferred to the host computer.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an effective data transferring apparatus capable of preventing data read from a sector other than a target sector from being transferred to a host computer in a hard disk drive employing a headerless servo recording method.

Hereinafter, an operation according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a block diagram of a conventional hard disk drive in which a printed circuit board assembly (PCBA) and a head disk assembly (HDA) are combined. FIG. 2 is a block diagram of a conventional hard disk drive having two disks 2 and corresponding four heads 4 FIG. 2 illustrates an example of a multi-plate type hard disk drive. In a hard disk drive using a multiple platter system, the disks 2 are typically mounted in a single spindle motor 14 in the form of a stack, with each disk surface corresponding to one head 4. The head 4 is located on the surface of the disk 2 and is mounted on a vertically elongated arm 6 of an arm assembly of a rotary voice motor (VCM) 1024. The preamplifier 8 pre-amplifies the signal picked up by one of the heads 4 at the time of data reading and applies the analog read signal to the read / write channel circuit 10, At the time of data write, the encoded write data applied from the read / write channel circuit 10 is caused to be written on the disk 2 by driving a corresponding one of the heads 4. At this time, the preamplifier 8 selects one of the heads 4 under the control of a disk data controller (Dia or Data Controller: DDC) 28 controlled by the microcontroller 14. The read / write channel circuit 10 detects and decodes the data pulse from the read signal applied from the preamplifier 8 to generate read data RDATA, decodes the write data WDATA applied from the DDC 28, . The read / write channel circuit 10 also demodulates the head position information, which is a part of the servo information recorded on the disk 2, to generate a position error signal (PES). The PES generated from the read / write channel circuit 10 is applied to an analog-to-digital converter 12, and the A / D converter 12 converts the PES into a digital step value And provides it to the microcontroller 14. The DDC 28 is controlled by the microcontroller 14 and writes the data received from the host computer to the disk 2 via the read / write channel circuit 10 and the preamplifier 8, And transmits the read data to the host computer. The DDC 28 also interfaces communication between the host computer and the microcontroller 14. The microcontroller 14 controls the DDC 28 in response to a read / write command received from the host computer and controls track seeking and tracking. At this time, the microcontroller 14 controls the track following by using the PES value applied from the A / D converter 12. The D / A converter 16 converts a control value for controlling the position of the heads 4 generated from the microcontroller 14 into an analog signal and outputs the analog signal. The VCM driving unit 18 generates a driving current I (t) for driving the actuator by a signal applied from the D / A converter 16 and applies the driving current I (t) to the VCM 20. [ The VCM 20 horizontally moves the heads 4 on the disk 2 in accordance with the direction and level of the drive current input from the VCM driver 18. [ The motor control unit 22 controls the spindle motor driving unit 24 according to a control value for controlling the rotation of the disks 2 generated from the microcontroller 14. [ The spindle motor driving section 24 drives the spindle motor 26 to rotate the disks 2 under the control of the motor control section 22. [ The buffer memory 30 connected to the DDC 28 temporarily stores data transmitted between the disk 2 and the host computer under the control of the DDC 28.

FIG. 3 is a block diagram of an effective data transmission apparatus according to the present invention. Referring to FIG. 3,

The disk transferring unit 32 transfers the data read from the disk 2 to the buffer memory 30. When the data of one sector read from the disk 2 is transferred to the buffer memory 30, ) Is incremented by one.

The host transfer unit 34 transfers the data stored in the buffer memory 30 to the host computer by the disk transfer unit 32. When the data of one sector is transferred from the buffer memory 30 to the host computer, 36) is decremented by one.

The valid sector counter 36 counts when one sector of data from the disk 2 is transferred to the buffer memory 30 and counts down when data of one sector is transferred from the buffer memory 30 to the host computer. Indicates the number of data sectors existing in the sector 30.

The minimum sector counter 38 indicates the number of the minimum sectors that should be present in the buffer memory 30, and its value is determined by the microcontroller 14.

The counter comparison unit 40 compares the count value of the valid sector counter 36 with the count value of the minimum sector counter 38. If the count value of the valid sector counter 36 is larger than the value of the minimum sector counter 38, And outputs the generated signal to the host transmission unit 34. At this time, the host transmission unit 34 transmits data of one sector from the buffer memory 30 to the host computer by the data transmission signal.

Hereinafter, the operation of the effective data transmission apparatus having the above-described configuration will be described.

First, when a data read command is received from the host computer, the microcontroller 14 uses the servo information written in the servo field to position the head 4 on the target track. Then, the target sector-laddered data on the target track via the head 4 is pre-amplified by the preamplifier 8 and then input to the DDC 28 through the read / write channel circuit 10. [ At this time, the read data input to the DDC 28 is transferred to the buffer memory 30 by the disk transfer unit 32. When the read data is transferred to the buffer memory 30, the value of the valid sector counter 36 is increased and this value is compared with the value of the minimum sector counter 38 by the counter comparing unit 40. At this time, if the count value of the valid sector counter 36 is larger than the value of the minimum sector counter 38, the counter comparing unit 40 generates a data transmission signal and outputs it to the host transmission unit 34. Accordingly, the host transmission unit 34 transmits the read data stored in the buffer memory 30 to the host computer in response to the data transmission signal input. As a result, the valid sector counter 36 decrements (by data transfer to the host computer) and again compares the count value of the valid sector counter 36 with the value of the minimum sector counter 38. If the count value of the valid sector counter 36 is less than the value of the minimum sector counter 38 as a result of the comparison, the counter comparison unit 40 determines that the host transfer unit 34 After the signal is disabled, new data is sent from the disk 2 to wait for the value of the valid sector counter 36 to increase. If the data is transferred in the above-described manner, data read from the disk 2 is not transferred to the host computer until data corresponding to the minimum sector counter 38 is transferred, If the data read in (2) is confirmed to be on a sector other than the target sector, the data written to the target sector can be read again through the retry operation. That is, even if data is read from a sector other than the target sector in the hard disk drive employing the headerless servo, it is not transmitted to the host computer.

As described above, the present invention has an advantage in that reliability of a product can be secured by blocking data transmitted from a sector other than the target sector to the host computer.

Claims (3)

And a memory for temporarily storing data transferred between the disk and the host computer, the apparatus comprising: a disk for transferring data read from the disk to the memory, A host transfer unit for transferring data stored in the memory to the host computer during an enable period of a data transfer signal, and a counter for increasing the count when data for one sector is transferred from the disk transfer unit to the memory, A valid sector counter that counts down when data of a sector is transferred from the host transmission unit to the host computer; a minimum sector counter that indicates the number of the minimum sectors that should be present in the memory; If the value of the sector counter is greater than the value of By generating a data transmission signal of the block status to valid data transmission device characterized in that it consists of a counter comparator for output to the host transmission. The valid data transmission apparatus of claim 1, wherein the number of the minimum sectors is loaded from a control unit when a data read command is received from the host computer. 3. The effective data transmission apparatus of claim 2, wherein the hard disk drive is a hard disk drive employing a headerless servo recording method.