JPH06149716A - Disk data transfer system - Google Patents

Abstract

PURPOSE:To transfer data to a disk without modifying software when access from a central controller is positioned halfway in a record on a disk with respect to the system which accesses plural kind of disk devices differing in record length. CONSTITUTION:In the data transfer system which has a central processor 1, a main memory 2, a direct memory control part 3, plural disk devices 4 and 5, and a file memory control part 7 controlling disks, the file memory control part 7 is provided with auxiliary buffer memories consisting of a start buffer memory 12 and an end buffer memory 13 in parallel to a buffer memory 8 for temporarily storing data from CC or DK and further provided with a data editing means 15 which selects the buffer memories 12 or 13, puts data together with data written in the buffer memory 8, and sends the composite data out to the disks, thereby transferring data corresponding to plural kind of disk devices.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for accessing a plurality of types of disk devices having different record lengths. In a system that transfers data to a plurality of types of disks, it is necessary to control a plurality of types of disk devices having different record lengths. FIG. 4 shows a configuration example of a plurality of types of disk devices. In the figure, the record length of the disk device DK0 consists of one record length of 256 bytes, the record length of DK1 doubles of 512 bytes, and the record length of DK2 is 3 bytes.
Suppose there are double 768 bytes.

Data writing to DK1 may start or end at the 256th byte, and DK2
May start or end data writing from the 256th or 512th byte, but because of the hardware characteristics of the disk unit, writing is done in record units, so data is written in DK0 record units (256 bytes). Even if it is written, there is a problem that in the case of DK1 it is not possible to write from the middle of a record unit (512 bytes), and in the case of DK2 it is not possible to write from two places in the middle of a record unit (768 bytes). .

[0003]

2. Description of the Related Art FIG. 5 shows a block configuration example of a conventional system for transferring data to and from a plurality of types of disks. In the figure, 31 is the central processor (CC) of the system,
32 is a main memory (MM), 33 is a direct memory access control unit (DMAC), 34 and 35 are a plurality of disk devices (DK0, DK1), 36 is a CC interface unit for notifying commands, addresses, and the number of records from the CC (CC
INF), 37 indicates a file memory control unit (FMC) for controlling the disk.

File memory control unit FMC37 shown by a dotted line
Is a buffer memory (BM) 38 that temporarily stores data from CC or DK, a data transfer control unit (DTC) 39 that transfers data from MM to DK, and a microprocessor (MPU) that controls the operation in the FMC. ) 40 and a disk control unit (DKC) 41 for controlling the DK. The buffer memory (BM) 38 is connected to the local bus by an address counter for the buffer memory, and the address counter is composed of a CC side counter (BMCCNT) 42 and a DK side counter (BMDCNT) 43.

The record address of DK0 34 to be accessed from CC 31 and the number of transfer records are notified to FMC 37, and D
Issue an access command of K034 to FMC37. FMC37
Upon receiving this command, the MPU 40 sets the record address and the number of transfer records in the DTC 39 and activates the data transfer. When the command is Write, DTC39 is MM
The data from 32 is written to BM38, then the data of BM38 is written to DK034, and this is repeated until the transfer is completed. When the command is Read transfer, DTC39 is DK
The data of 034 is written in BM38, the data of BM38 is written in MM32, and this is repeated until the transfer is completed.

At this time, access to the DK034 is made on a record basis, and the amount of data sent from the memory MM32 must be specified in consideration of the record length of the DK034. For example, in the disk configuration example of FIG. 4, consider a case where an instruction to write one record data from record address 0 to CC31 is received. If you try to access the disk DK135 with twice the record length,
Writing does not have to be performed up to the middle of the code address 0 of 35, but because of the hardware characteristics of the disk, it is written in record units, so data is also written in this portion.

[0007]

In order to solve this problem, it is necessary to change the software corresponding to different disk devices, but it takes a considerable number of man-hours to develop the software, so it is necessary to use hardware. It is hoped that this will be resolved.

The present invention recognizes the record information when the MPU reads the disc type, and when the access from the CC is located in the middle of the record of the disc, the data of the record is read by the auxiliary puffer memory. Then, the data written in the puffer memory is combined and edited and transferred to the disk to transfer the data without changing the software.

[0009]

FIG. 1 is a block diagram showing the principle of a data transfer system according to the present invention. In the figure, 1 is a central processor (CC) of the system, 2 is a main memory (MM), 3 is a direct memory access control unit (D).
MAC), 4 and 5 are a plurality of disk devices (DK0, DK)
Reference numerals 1) and 6 denote a CC interface unit (CCINF) that notifies a command, an address, and the number of records from the CC, and 7 denotes a file memory control unit (FMC) that controls a disk.

File memory control unit FMC7 shown by a dotted line
Includes a buffer memory (BM) 8 for temporarily storing data from CC or DK, a data transfer control unit (DTC) 9 for transferring data from MM to DK, and a microprocessor (F) for controlling the operation in the FMC. MPU) 10 and DK
The following means is added to a conventional circuit having a disk control unit (DKC) 11 for controlling the.

The buffer memory (BM) 8 is provided with two auxiliary buffer memories consisting of a start buffer memory (BMS) 12 and an end buffer memory (BME) 13, and the output side of the auxiliary buffer memory is buffered. It is connected in parallel with the output side of the memory (BM) 8 and the buffer memory (B
The input side of M) 8 is connected to the local bus by the CC side address counter (BMCCNT) 14 of the buffer memory.

Data editing means 15 is provided for selecting the above-mentioned two auxiliary buffer memories 12 and 13 and synthesizing the data to be written in the buffer memory 8 and sending the data to the disk. Configure to transfer.

[0013]

The minimum record length of the disc that can be accessed by the system is one block, and the CC transfers data by using this as a unit data. Assuming that the maximum record length of the disk accessible by the system is N blocks, the buffer memory for N-1 blocks is 2 in addition to the buffer memory BM.
(BMS, BME) are prepared.

When the MPU reads the disc type,
When the record information is recognized and the access from the CC is located in the middle of the record of the disc, the data of the record is read by the BMS and BME, combined with the data written in the BM, and transferred to the disc. Data can be transferred without changing the software.

[0015]

FIG. 2 shows a block diagram of an embodiment of the present invention. In the figure, the same numbers as in FIG. 1 indicate the same device names.
The figure shows multiple types of disk drives with different record lengths (DK
0, DK1) access system.

This system comprises a central processing unit (CC) 1
And a main memory (MM) 2, a file memory control unit (FMC) 7 that controls disks, and a direct memory access control unit (DMAC) 3 that controls data transfer between MM and FMC. Has a buffer memory (BM) 8 for temporarily storing transfer data, and data is hard transferred by a data transfer control unit (DTC) 9 which transfers data from MM to DK in the FMC.

The disks accessed by this system are
As shown in the disk configuration example in Fig. 4, assume that there are two disks with a record length of 256 bytes (DK0) and 512 bytes (DK1), and 512 bytes are written from the 257th byte of DK1. think of.

The software of the system accesses with the minimum record length of the disc accessible by the system as one block, and in this case, writes the command information of writing two blocks from the block No. 1 to the FMC. Upon receiving this, the FMC MPU reads the access start record number (SRA) from the record length of the disc when reading the disc type.
D) and up to which byte of access information (SBYTE)
Read the last record No. (ERAD) and the number of bytes of the access (EBYTE), calculate the transfer record number (RRCS), and set SBYTE to the start conversion register (SCH
R) 16, EBYTE to end conversion register (ECHR) 17, transfer record number to actual transfer record size register (RRCSR) 18
Write in.

In this case, the transfer is started at the record No. 0.
256 bytes, the end of transfer is 255 bytes of record No. 1,
The number of transfer records is 2. Next, it is determined whether or not the start of transfer is in the middle of a record, and if it is in the middle, the start record flag (SRRF) 19 is set and the start record from the disk is read.

Here, the hardware has a buffer memory selector (BMSEL) 20 for selecting a buffer memory, and the selector 20 selects the BMS 12 according to the start record flag (SRRF) 19 and the discrete condition, and the disk configuration of FIG. The data in the part of the example is read, and the rest is read and discarded. Next, it is determined whether the end of transfer is in the middle of a record, and if it is in the middle, the end record flag (ERRF) 21 is set, the part of the last record is read from the disk,
Discard other parts.

Here, the buffer memory selector (BMSEL) 2
When 0 is selected, the BME 13 is selected based on the end record flag (ERRF) 21 and the discrete condition. Then, MPU10 is DTC
The transfer is activated to 9 and waits for the end of transfer by hardware.

The DTC 9 issues a data transfer request on the MM2 side and transfers the data to the BM8. When the BM8 becomes full, the disk side transfer starts, but at this time, the selector 20
Selects BMS12 according to the value of the start record flag (SRRF) 19, the value of the record counter (RECCN) 22 that counts the number of transferred records, and the condition that it is a write transfer.
The MS12 data is written to the disc. The buffer memory address is the buffer memory counter (BMCNT) 23.
It is supplied by and is counted up by the transfer command,
It is cleared by the buffer memory clear circuit (BMCR) 24.

The count value is the start conversion register (SCH
When it becomes equal to (R) 16, the selector 19 selects BM8,
Thereafter, the data of BM8 is written to the disc until the final record. Counter (BMCNT) 2 at transfer of last record
When the value of 3 becomes equal to the value of the end conversion register (ECHR) 17, the selector 19 selects BME13 and the data of BME13 is written to the disk.

Next, FIG. 3 shows an embodiment of an operation flow chart of writing to the disk device of the present invention. In FIG. 3, (1) Command information is written to FMC from CC. (2) Read command information from CC in FMC. (3) The FMC reads the disc information from the DK. (4) Calculate the start record number. (SRAD) (5) Calculate the start byte. (SBYTE) (6) Calculate the end record number. (ERAD) (7) Set the number of transfer records. (RRCS) (8) Write the transfer record count (RRCS) to the actual transfer record size register. (9) Check if the start access information (SBYTE) is "0". (10) Set the start record flag (SRRF) if it is not "0". (11) Set the disc. (12) Read the start record set in BMS in DTC. (13) If the start access information (SBYTE) is "0", check whether the end access information (EBYTE) is "511". (14) If it is not "511", set the end record flag (ERRF). (15) Set the disk. (16) Read the end record set in BME in DTC. (17) If the end access information (EBYTE) is "511", the disk is set, and (18) the transfer to the DK is started by the DTC. (19) Transfer data to DK by DTC. BM
Data is transferred by editing in the order of S → DK, MM → BM → DK, BME → DK. (20) End data transfer from MM to DK.

In the operation flow of the above embodiment, (4)-
(16) is a part added to the conventional operation flow. In the conventional operation flow, data transfer is performed by MM → BM → DK in (19). The location data is not written correctly.

[0026]

The data is written in the above procedure, and the software sets the minimum record length as one unit.
It is possible to transfer without being aware of other record lengths.

[Brief description of drawings]

FIG. 1 is a block diagram of the principle of the present invention.

FIG. 2 is a block diagram of an embodiment.

FIG. 3 is an operation flowchart of the embodiment.

FIG. 4 is a configuration example of a plurality of types of disk devices.

FIG. 5 is a block diagram of a conventional example.

[Explanation of Codes] 1,31 Central Processor (CC) 2,32 Main Memory (MM) 3,33 Direct Memory Access Control Unit (DMAC) 4, 5, 34, 35 Multiple Disk Devices (DK0, DK)
1) 6,36 CC interface unit (CCINF) 7,37 File memory control unit (FMC) 8,38 Buffer memory (BM) 9,39 Data transfer control unit (DTC) 10,40 Microprocessor (MPU) 11,41 Disk control unit (DKC) 12 Start buffer memory (BMS) 13 End buffer memory (BME) 14, 42 CC side address counter (BMCCNT) 15 Data editing means 16 Start conversion register (SCHR) 17 End conversion register (ECHR) 18 Actual transfer record size register (RRCSR) 19 Start record flag (SRRF) 20 Buffer memory selector (BMSEL) 21 End record flag (ERRF) 22 Record counter (RECCN) 23 Buffer memory counter (BMCNT) 24 Buffer memory clear circuit (BMCR) ) 43 DK side address counter (BMDCNT)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kenji Fujizono 1015 Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Fujitsu Limited

Claims (3)

[Claims] 1. System central processor CC
(1), a main memory MM (2), a direct memory access control unit (3), a CC interface unit (6) for notifying a command, an address, and the number of records from the CC, and a file memory control for controlling a disk A plurality of types of disk devices DK (4) to
In the data transfer system for accessing (5), the file memory control unit (7) is accessed from CC or DK.
Buffer memory (8) for temporarily storing data from
And a data transfer control unit (9) for transferring data from the MM to the DK, a microprocessor (10) for controlling the operation in the control unit, and a disk control unit (11) for controlling the DK. (8) is provided with two auxiliary buffer memories including a start buffer memory (12) and an end buffer memory (13), and the output side of the auxiliary buffer memory is the output side of the buffer memory (8). Connected in parallel, the input side of the buffer memory (8) is connected to the local bus by the CC side address counter (14) of the buffer memory, and the above two auxiliary buffer memories (12) and (13) are selected to A data editing means (15) for synthesizing the data written in the memory (8) and sending it to the disk is provided,
A disk data transfer method characterized by transferring data corresponding to multiple types of disk devices. 2. In the above system, the minimum record length of the disk that can be accessed by the system is one block, CC (1) transfers data by using this as unit data, and the maximum record length of the disk that the system can access is N blocks. Then, two auxiliary buffer memories (12) and (13) provided in parallel with the buffer memory (8) are used as N-1 blocks of buffer memory, and data writing to the disk and data reading / transfer from the disk are performed. In this case, when the microprocessor (10) recognizes the record information when reading the disc type, and the access from CC (1) is located in the middle of the record of the disc, the data of the record is stored in the buffer memory ( 12) and (13) read and combined with the data written in the buffer memory (8) 2. The disk data transfer method according to claim 1, wherein the unnecessary data is read out without being written in the buffer memory (8), is written out, is written into the buffer memory (8) in units of blocks, and the data is sent. . 3. In the above system, the data editing means (15) includes a record counter (22) for counting the number of transfer records, a record size register (18) for storing the number of transfer records, and a disk access from the CC. If it is located in the middle of the record, the start conversion register (16) that stores information on which byte in the transfer start record has the transfer start position, and which byte of the last record has the transfer end position End conversion register (17) that stores information, flag (19) indicating that the start record is being read, and flag (21) indicating that the last record is being read
And a buffer memory selector (20) that selects the buffer memory (8) and the auxiliary buffer memories (12) and (13) by looking at the values of the flag (19), the flag (21) and the record counter (22). The disk data transfer system according to claim 1, further comprising: