JPH0339351B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to a system for controlling a plurality of different types of disk devices using the same controller.

(b) Background of the Technology Disk devices differ in the number of cylinders, number of heads, and seek operation sequences depending on their capacity, but the control methods related to reading and writing are often almost the same.

Therefore, if the number of cylinders, number of heads, and seek operation sequence of each disk device mentioned above can be searched,
One controller can control different types of disk devices.

The present invention has been devised by focusing on the characteristics of controlling a plurality of disk devices of different types.

(c) Prior art and problems Conventionally, when controlling a disk device, each time the disk device changes, the settings on the disk controller must be changed or the disk controller must be changed.
Because it was newly designed to match the connected disk devices, there were problems such as an increase in the number of controller types, complicated settings, and reduced operational and maintenance efficiency. Another method is to install a circuit to set and hold model information in the disk device, and to report the above model information as response information in response to a request from the controller (for example, issuing a sense command). .

In this case, an extra circuit and a special interface for reporting model information using sense commands are required, resulting in an increase in price. The other method is to create a table in the system program and set the model information of the disk device connected to the disk controller.
It was necessary to change the system program every time the type or number of disk devices connected to the disk controller changed.

(d) Purpose of the Invention In view of the above-mentioned drawbacks of the conventional technology, the present invention provides a single disk controller that allows the user to set the type of disk by means other than software (table settings on the system program) or terminal settings (flag settings) on the hardware. The object of the present invention is to provide a method that makes it possible to control different disk devices.

(e) Structure of the Invention According to the present invention, in a disk controller that controls a plurality of different types of disk devices, a letter in which device identification data is written in a specific record of a disk storage medium, and the data is means for reading and determining an operation mode for controlling the disk storage medium based on the data; and means for notifying software of the data;
Means for protecting the record recording the data, and device identification data for storing the record in duplicate on a cylinder diagonally, and when one data is abnormal, the other data is used. This is achieved by providing a method for controlling the disk device according to the contents of the configuration record, and a controller protects the disk storage medium and the device identification data stored in the specific record. By reading, retaining, and referring to the information when executing each command, there is an advantage that any disk device connected to the controller can be controlled.

(f) Embodiments of the Invention First, the general operation when controlling a disk device will be explained.

In the central processing unit (not shown), seek commands, read commands, write commands, etc. are executed.

In the case of a seek command, the execution of the command determines the next read to be executed, the data read in the write command, and the write position.
However, it is also possible to read and write by directly specifying the head position and record position using read and write commands.

The present invention calculates the position of a certain record to be read or written, and calculates the timing for performing a seek operation as a result.
This is a method to obtain the number, cylinder Cy number, and seek mode.

Embodiments of the present invention will be described in detail below with reference to the drawings.
FIG. 1 is a diagram illustrating an example of connection between a disk controller embodying the present invention and various disk devices (hereinafter referred to as units), in which 1 is a disk controller, and 11 is a device type identification register necessary for implementing the present invention. (DTRR), 2 is the unit. Figure 2 is a diagram showing the differences in devices for each unit number, and shows the number of heads and
It is understood that the number of cylinders and seek mode are different. Here, the normal seek mode is a mode in which pulses are issued to perform a seek operation in accordance with the time required to move the head from one cylinder to the next. Also SU/
In the mode with SD, when moving the head over a large distance, it is first moved at the above normal speed, then moved at high speed in the middle, and finally reduced to normal speed, making it more efficient overall. The purpose of this is to perform a seek operation.

Depending on the number of heads He, the number of cylinders Cy, and the seek mode, for example, the processing when calculating an address in the central processing unit and, as a result, the control method of the seek operation will change.

FIG. 3 is a diagram showing an example of device identification data provided on the disk storage medium of each unit, which is the main focus of the present invention. They are provided in head 0, sector 0, and sectors on the diagonal line thereof.

Here, A indicates a disk storage medium of a certain unit, and 0 to 15 are record Sec numbers. B is a diagram showing each record of cylinder Cy0 and head He0 expanded on a plane, and C is a diagram showing an example of storing the above device identification data. In this example, record Sec0 or facing record Sec8 Stored.

Then, the maximum head number is stored in He,
The maximum cylinder number is stored in Cy, and the seek operation mode is stored in Seek.

The operation of the present invention will be described below with reference to FIGS. 1 to 3.

First, for example, when the central processing unit uses the unit 2 for the first time, it uses a special command to change the cylinder Cy0, head He0, record Sec0, and diagonal line of each unit 2, as shown in Figure 3. Write the device identification data (He, Cy, Seek) in record Sec. The operation of writing with this special command functions as a protection mechanism for the device identification data.
Further, for the main write operation, a method of writing using an operation console or the like provided in the unit 2 itself may be considered.

If the unit is new and has not been formatted yet, the device identification data should be written using the above method after the formatting process is completed.

In addition to track 0 (cylinder 0, head 0), device identification data is also provided on the diagonal line.
The diagonal line is used to minimize malfunctions caused by damage to the disk storage medium caused by the head touching the disk storage medium when the power is turned on or off. This is because it is the most effective considering the following.

When the system is powered on, unit 2 automatically seeks to track 0.

For units 2 that do not have automatic seek, the disk controller 1 causes them to seek.

However, the seek speed does not differ depending on the unit because the seek operation is performed while detecting and checking the track 0Cy0 signal for each cylinder.

When a sense command is sent from the central processing unit of the system, the disk controller 1 reads the device identification data, holds it in the register 11 for each unit, and operates to report it to the central processing unit.

The central processing unit calculates addresses, creates commands, etc. regarding the data to be processed according to the contents.

The device identification data held in the disk controller 1 is referenced every time a command to access a certain unit is sent from the central processing unit, and is referenced every time a command is sent from the central processing unit to access a certain unit. and the seek speed (normal, with SU/SD) are determined, and each unit is controlled according to the operation sequence.

(g) Effects of the Invention As explained above in detail, the disk control method of the present invention stores device identification data (He, Cy, Seek) in a specific record of a disk storage medium in advance.
By writing this data, the disk controller reads and retains the data, and is controlled to report it to the central processing unit. Therefore, the disk controller changes the control method depending on the disk difference for each unit number. be able to.

Therefore, it is possible to inexpensively control disk devices with different disks for each unit number using one controller.

[Brief explanation of the drawing]

FIG. 1 is a diagram illustrating an example of the connection between a disk controller embodying the present invention and various disk devices, FIG. 2 is a diagram showing the differences in models for each disk device number, and FIG. FIG. 3 is a diagram showing an example of device identification data provided in FIG. In the drawing, 1 is a disk controller;
1 indicates a disk type identification register, 2 indicates a disk device (unit), He indicates the maximum head number, Cy indicates the maximum cylinder number, and Seek indicates the seek operation sequence.

Claims (1)

[Claims] 1. In a disk controller that controls a plurality of different types of disk devices, means for writing device identification data in a specific record of a disk storage medium, and an operation for reading the data and controlling the disk storage medium based on the contents. means for determining a mode; means for notifying software of the data; means for protecting the record storing the data; storing the record in duplicate on a diagonal on a cylinder; and means for protecting device identification data that uses the other data if the data of the specific record is abnormal, and the disk device is controlled according to the contents of the specific record.