JPH087665B2 - Peripheral control device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a peripheral control device, and more particularly to a control method for writing data to an irreversible storage medium that cannot be erased and rewritten.

[Conventional technology]

Conventionally, this type of peripheral control device generates a data overrun due to overload of a host device during transfer of write data.
Alternatively, when a hardware error or data parity error that occurs in the host device or on the interface with the host device is detected, some or all of the sector in which the error occurred is already written on the medium. I was there.

[Problems to be Solved by the Invention]

Therefore, in a medium in which data cannot be erased and rewritten, a process of invalidating the sector as a defective sector and a process of defining the alternative sector in any area on the medium are necessary. These have the drawbacks that the capacity is substantially reduced and that complicated bad sector / replacement sector processing is required not only at the time of writing but also at the time of reading, resulting in a reduction in performance.

[Means for solving the problem]

The present invention reduces the occurrence of defective sectors by checking as much as possible in sector units before writing the data from the host device on the medium, and makes it easy to secure a predetermined storage capacity and to increase the storage capacity. It is intended to provide a peripheral control device having high performance and high reliability.

That is, the present invention provides a means for receiving data to be written on an irreversible medium that records information by changing the characteristics of the medium or removing a part of the medium, and writing to the medium the received data having a unit write length of the medium or more. A means for temporarily storing before, a means for detecting that the storing means stores data of a unit length or more, a means for detecting an abnormality occurring during receiving of data, and a case of detecting an abnormality Means for stopping the writing of the data held in the temporarily storing means onto the medium. Alternatively, the present invention provides means for receiving data to be written to a medium by dividing the data into a unit length for writing from the host device, means for temporarily storing the received data of the unit length before writing to the medium, and an abnormality. And means for stopping writing.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

Referring to FIG. 1, an optical disk control device (hereinafter abbreviated as ODC) 1 which is an embodiment of the present invention is connected to a host device 2 and an optical disk device (hereinafter referred to as ODU) 3, and this ODC 1
Is a transfer control unit 10 that controls the transfer of data and commands with the higher-level device 2, a data buffer unit 11 that temporarily stores the data sent from the higher-level device 2, and the number of data that is continuously received from the higher-level device 2. The data stored in the parity check unit 13 and the buffer unit 11 for detecting the parity error of the data received from the data counter 12 and the higher-level device 2 is ODU3.
To the write control unit 14, the parity check unit 15 that detects a parity error in the write data, the read control unit 16 that controls the transfer of the read data from the ODU 3, and the number of data transfers of the write data and the read data. It includes a data counter 17 for controlling and a micro program controller 18 for controlling the operations of the respective parts.

The micro program control unit 18 includes means for recognizing the address of each sector read from the medium and the transfer control unit 1.
0, write control unit 14, read control unit 16 via the host device 2,
Alternatively, it has means for transmitting / receiving operation instructions or transmitting / receiving stakes with the ODU 3, respectively. Data is written and read in the ODU3. The medium is a write-once optical disc medium that cannot be erased and rewritten.

FIG. 2 shows the relationship between each data transfer timing and the recording format on the medium when writing data to the sector. A plurality of sectors are arranged on a large number of tracks arranged on concentric circles of the medium in the circumferential direction of each track. Each sector is composed of an ID section indicating a physical address, a flag section indicating a defective sector, and a data section in which a logical address and data are written. The ID part is pre-formatted in advance. Focusing on the sector N, the data transfer from the higher-level device 2 to the buffer unit 11 is started during the write operation of the sector N-1, and after the data of the ID unit of the sector N is read, the data in the buffer is the data of the sector N. Written to the department. At this time, the defective sector flag portion must be in a non-written state.

 FIG. 3 shows a processing flow of this embodiment.

Next, the write operation of this embodiment will be described with reference to FIG. 1. The microprogram control unit 18 of the ODC 3 of this embodiment requests data transfer from the host device 2 based on an instruction from the host device 2. . After that, the micro program control unit 18 sets the data number of the write data forming the data portion of each sector in the data counter 12. When a value is set in the data counter 12, data transfer for one sector is started. Further, the ODU 3 is instructed to read the ID section of the sector through the write control section 14 and the data length is set in the data counter 17. The data of the ID portion, that is, the sector address, sent from the ODU 3 passes through the read control unit 16 and is compared with the target sector address in the microprogram control unit 18. If the comparison does not match, the instruction is reissued to ODU3 to read the ID of the next sector.
That is, the read and compare operations are repeated until the target sector is detected. When the address of the read ID coincides with the expected value, it is checked in the data transfer from the higher-level device 2 whether one sector of data to be written in the data section of the sector is already stored in the buffer section 11. That is, if the data counter 12 is decremented by the byte unit to be transferred and becomes "0", 1
Judge that the data for the sector has been sent. At the same time, the transfer control unit 10 suspends the reception of data from the higher-level device 2 until a value other than "0" is set again in the data counter 12 and an instruction to restart the transfer is given. If the data transfer for one sector in the sector is not completed from the host device 2 by the start of writing the data section, that is, if the data counter 12 is not "0", writing to the sector is not performed, Further, the ID reading and comparing operations are continued until the medium makes one round and the same sector is detected again. If the data counter 12 becomes "0" by that time, writing is possible.

By detecting the ID of the target sector, the data counter 12 becomes "0" by the time the writing starts, and if there is no error, the microprogram control unit 18 sends the ODU3 through the write control unit 14.
To write to the data section. Then set the number of data to be transferred in the sector to the data counter 17,
The write control unit 14 is instructed to start the data write operation.
The data counter 17 feels 1 each time 1 byte of data in the buffer 11 is transferred to the ODU 3. Therefore 1
When all the data for the sector is transferred from the buffer 11 to the ODU 3, the data counter 17 becomes “0”.

In the multi-sector continuous write command, when the microprogram control unit 18 determines that the sector instructed to write is not the last, it receives the write data of the next sector from the host device 2 and stores it in the buffer 11. Set the number of data in the next sector to
Instruct 10 to restart data transfer. After that, the writing operation of the data portion instructed to the ODU3 is completed.
That is, it waits for the data counter 17 to reach "0". The data counter 17 becomes "0", the writing of the first sector is completed, and if there is no error, the ID of the next sector to ODU3.
Instruct to read the copy. Subsequent operations are the same as for the first sector.

When the reading of the ID part is completed, it is confirmed that the data transfer from the host device 2 to the sector is completed, and whether or not there is an error related to the reading of the ID part and the data transfer from the host device 2 is checked. When an error is detected here, for example, when there is a parity error in the write data transferred from the host device 2 and the parity check unit 13 detects this, the microprogram control unit 18 issues a write instruction for writing the data. To output to the ODU3 and report the sector address together with the error status to the host device 2. Therefore, the sector in which a parity error has occurred during data transfer from the higher-level device 2 is not written on the medium. Host device 2
Instructs the ODC 1 to write the remaining sectors including the error sector based on the report. When the data of the sector is stored in the buffer 11 that is retransferred without error, the microprogram control unit 18 instructs the ODU 3 to write the data, and writing to the unwritten sector becomes possible.

As described above, by dividing the data transfer into sector units in the case of writing a plurality of sectors with one write command from the higher-level device 2, it is possible to specify the sector address where the error occurred.

During the write operation of the data part in ODU3, that is, ODC1
When an error is detected during data transfer from the buffer 11 to the write control unit 14 and further to the ODU 3, for example, when a parity error is detected by the parity check unit 15, the microprogram control unit 18 writes the same sector after completion of writing. The ODU3 is instructed to write a predetermined data pattern, that is, a defective sector flag into the flag part of the. Furthermore, by writing the address and data of the original error sector to the data part of one of the unused alternative sectors among a plurality of alternative sectors that are defined in advance on the same track, this error It is possible to use a sector, that is, a sector instead of a bad sector. Referring to Figure 2, the microprogram control unit 18 instructs the writing of the N-th sector to the ODU3, after the start of forward ODU3 navel data from the buffer 11 (time t _6), from the host device 2 N + 1 th sector Buffer of data 11
The transfer control unit 10 is instructed to receive (time t ₇ ).
Thereafter, detects that the writing of the N-th sector is completed (time t _8), reads the ID part of the N + 1-th sector (time t ₁₀ ~t _11), issues writing instruction to the OUD3 the data portion (time t ₁₂₎ and N + 1 th data has not yet been forwarded all the buffer 11 immediately before (time t ₉ ~t
₁₃ ). That is, the occurrence of data overrun. At this time, the microprogram control unit 18 immediately stops sending the write instruction for the (N + 1) th data portion. Further, if all the data is stored in the buffer 11 by the time the disk rotates once and the same sector is detected again, the data is written in the sector. Therefore, the processing for making the sector concerned a defective sector and the alternative sector processing are unnecessary.

〔The invention's effect〕

As described above, the present invention, as described above, writes error data in which a data overrun or a parity error has occurred in a host device by always storing one or more sectors of data in a buffer before writing the data in units of sectors. This is effective in preventing a decrease in storage capacity and performance.

[Brief description of drawings]

FIG. 1 is a block diagram partially showing an embodiment of the present invention,
FIG. 2 is a diagram showing a recording format on a medium used in an embodiment of the present invention and a timing of data transfer at the time of writing, and FIG.
The drawing is a flow chart showing the processing procedure at the time of writing in one embodiment of the present invention. In FIG. 1, 1 ... Optical disc control device, 2 ... Upper device, 3 ... Optical disc device, 10 ... Transfer control unit, 11
...... Buffer section, data counter, 13 ...... Parity check section, 14 ...... Write control section, 15 ...... Parity check section, 16 ...... Read control section, 17 ...... Data counter, 18 ...
… Microprogram control unit, 100 in Fig. 2…
… ID part, 101 …… Flag part, 102 …… Data part.

Claims (2)

[Claims] 1. Means for receiving data to be written to an irreversible medium for recording information by changing characteristics of the medium or removing a part of the medium from a host device, and the received data having a write unit length of the medium or more. Means for temporarily storing the data before writing on the medium, means for detecting that the storing means stores data having a unit length or more, and means for detecting an abnormality that occurs during the reception of the data. A peripheral control device, which stops writing the data held in the temporarily storing means onto the medium when the abnormality is detected. 2. A unit for receiving data to be written to an irreversible medium, which records information by changing the characteristics of the medium or removing a part of the medium, into a unit length for writing from the host device to the medium, and the received unit. A means for temporarily storing long data before writing to a medium, a means for detecting an abnormality occurring during reception of the data, and a means for temporarily storing the abnormality when the abnormality is detected. And a means for stopping writing of existing data on the medium.