JP2581468B2 - Non-SCSI device access method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device (non-SC) connected by an interface specific to a computer system.
SI (Small Computer System Interface) device)
Can be used directly from other computer systems connected to the computer system via a SCSI bus (shared)
The present invention relates to an access method of a non-SCSI device which is enabled.

[0002]

2. Description of the Related Art As a conventional example of a method for sharing a non-SCSI device, there is a method as disclosed in Japanese Patent Application Laid-Open No. 4-297945 ("Access Method for Electronic File System"). In this method, a gateway device is provided at the connection destination of the SCSI bus, and the SC
By changing the SI command, it is possible to use an externally connected non-SCSI device.

[0003]

However, in this system, the gateway device must be connected by the SCSI bus without fail. Also, the ID is assigned to the gateway device.
Has to be allocated, which has been an obstacle to expansion and connection. Further, in this method, a non-SCSI device connected by an interface unique to a computer system cannot be directly used by another computer system connected to the computer system by a SCSI bus.

[0004] The present invention has been made to solve such a problem, and an object of the present invention is to easily perform expansion and connection, and to perform physical connection over an existing SCSI connection. A non-SCSI device that can directly use a non-SCSI device connected by a computer system-specific interface from another computer system connected via a SCSI bus without making changes, adding devices, or changing terminal settings. To provide an access method.

[0005]

In order to achieve such an object, the first invention (the invention according to claim 1) includes an SCS.
The command sent through the I bus is picked up, the picked up command is sent to the virtual device driver manager, and the command is assigned to an appropriate virtual device driver by the virtual device driver manager. The non-SCSI device connected to the virtual device driver is accessed according to the allocated command.

A second invention (an invention according to claim 2) picks up a command sent from another computer system via the SCSI bus, sends the picked up command to a virtual device driver manager, and the virtual device driver manager The command is allocated to a virtual device driver specified by a logical unit number included in the command, and a non-SCSI device connected to the virtual device driver is allocated to the virtual device driver via the allocated virtual device driver. In this case, the access is made according to the command.

[0007]

According to the present invention, therefore, in the first invention,
The command transmitted through the SCSI bus is allocated to an appropriate virtual device driver by the virtual device driver manager, and a non-SCSI device connected to the virtual device driver to which the command is allocated accesses according to the allocated command. Is done.

In the second invention, the SCS is transmitted from another computer system by the virtual device driver manager.
A command sent through the I bus is allocated to a virtual device driver specified by a logical unit number included in the command, and a non-SCSI connected to the virtual device driver to which the command is allocated is assigned.
The device is accessed according to the allocated command.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on embodiments. FIG. 1 is a configuration diagram of a system to which an embodiment of the present invention is applied. In the figure, 100 is a computer system, 200 is a SCSI bus, 300 is another computer system, 41 to 43 are computer systems 1
00 is a non-SCSI device connected by a unique interface.

The computer system 100 has a SCSI
The SCSI controller 1 that picks up the command sent to the computer system 100 transmitted through the bus 200 and the command picked up by the SCSI controller 1 are specified by the recognized LUN after recognizing the logical unit number (LUN) included in the command. A virtual device driver manager 2 for allocating the virtual device drivers 31 to 33 to be executed, an appropriate operation in accordance with a command transmitted from the virtual device driver manager 2, a non-SCSI device 41 to 4
Virtual device drivers 31 to 33 for mediating the transfer of commands to the
And a computer system basic unit 5 which constitutes the basic unit.

In this embodiment, the computer system 1
The virtual device driver manager 2 is installed at the time of system startup. The virtual device driver manager 2 not only receives a command for accessing a SCSI device connected to a SCSI interface (not shown), but also starts up the virtual device drivers 31 to 33 at the time of startup,
Allocation of LUN to 1-33, L included in command
Command allocation according to UN is also performed.

On the other hand, virtual device drivers 31 to 33
Executes a command assigned from the virtual device driver manager 2 in accordance with the actual situation of each interface;
It mediates the transfer of data to 1 to 43. By combining these, other computer systems 30
0 to the non-S connected to the computer system 100
Access to the CSIs 41 to 43 becomes possible.

Next, a specific operation of the system will be described with an example of SCSI command transfer. For reference, FIG. 2 shows the flow of data from the computer system basic unit 5 and the flow of data from the SCSI controller 1. The SCSI controller 1 holds its own ID in a register, and picks up a command for itself if the command is present on the SCSI bus 200. Then, the picked up command is sent to the virtual device driver manager 2.

The virtual device driver manager 2
The command sent from the CSI controller 1 is recognized by the LUN included in the command, and the virtual device drivers 31 to 33 specified by the recognized LUN.
Allocate to The virtual device drivers 31 to 33 pass a response according to the device type through the virtual device driver manager 2 to another computer system 3.
The access is executed by returning to 00.

For example, it is assumed that a non-SCSI device 41 connected to a parallel port existing on the computer system 100 is a printer, and this printer is accessed from another computer system 300.

An Identify message (hereinafter, referred to as an ID message) for making a logical connection defined in the SCSI specification is as shown in FIG. The manager 2 recognizes the LUN (number representing the target device) of the ID message and passes the ID message to the virtual device driver 31 specified by the recognized LUN.
In FIG. 3, if LUNTAR is "0", L
UN represents the target device.

If there is no problem in setting a logical connection, a command is subsequently transferred, and a method of processing data transmitted thereafter is defined. In the case of a printer, logical connection may not be established due to paper jam or the like. In other cases, a command for notifying start of printing is transmitted to the virtual device driver 31 after transmitting an ID message.

Thereafter, the print data is transferred to the printer 41 via the virtual device driver manager 2 and the virtual device driver 31, and access from another computer system 300 is executed. Then, after the printing is completed, a command to cancel the logical connection is sent from another computer system 300, and the printing is ended.

When the print data receiving buffer becomes full during printing and the data cannot be received anymore, the virtual device driver 31 sends a disconnect message defined in the SCSI specification to another computer system. By sending the SCSI bus 200, the release of the SCSI bus 200 is considered.

Thus, the non-SCSI device 41
~ 43 is regarded as a SCSI device and processed,
Other computers connected by the SCSI bus 200 only by changing the software configuration of the computer system 100 alone without changing the physical connection on the existing SCSI connection, adding devices, or changing terminal settings. The non-SCSI device 4 connected from the system 300 through an interface unique to the computer system 100.
1 to 43 can be used directly, and expansion and connection can be easily performed.

[0021]

As is apparent from the above description, according to the present invention, in the first invention, a command transmitted through the SCSI bus is allocated to an appropriate virtual device driver by the virtual device driver manager.
The non-SCSI device connected to the virtual device driver to which this command is allocated is accessed according to the allocated command, and the non-SCSI device is accessed.
By processing the I device as a SCSI device, it is possible to change the physical connection on the existing SCSI connection, add a device, or change the terminal setting without changing the setting of the terminal from other computer systems connected by the SCSI bus. , Non-SC connected by computer system specific interface
It is possible to directly use SI devices,
Connection can also be made easily.

In the second invention, the SCS is transmitted from another computer system by the virtual device driver manager.
A command sent through the I bus is allocated to a virtual device driver specified by a logical unit number included in the command, and a non-SCSI connected to the virtual device driver to which the command is allocated is assigned.
The device is accessed according to the allocated command, and the non-SCSI device is regarded as a SCSI device and processed, thereby changing the physical connection on the existing SCSI connection, adding the device, and changing the terminal setting. Without this, other computer systems connected by a SCSI bus can directly use non-SCSI devices connected by an interface unique to the computer system, so that expansion and connection can be easily performed. Become.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a system to which an embodiment of the present invention is applied.

FIG. 2 is a diagram showing a flow of data from a computer system basic unit shown in FIG. 1 and a flow of data from a SCSI controller.

FIG. 3 is a diagram showing a configuration of an ID message.

[Explanation of symbols]

100 computer system, 200 SCSI bus, 300 other computer systems, 41-43
Non-SCSI devices, 1 ... SCSI controllers 1, 2
... Virtual device driver manager, 31-33 ... Virtual device driver, 51 ... Computer system basic unit.

Claims (2)

(57) [Claims] 1. A command sent through a SCSI bus is picked up, the picked up command is sent to a virtual device driver manager, and the command is allocated to an appropriate virtual device driver by the virtual device driver manager, and the command is allocated. Non-SC connected to the virtual device driver via the virtual device driver
An access method for a non-SCSI device, characterized in that an SI device is accessed in accordance with an allocated command. 2. A method for connecting a SCSI from another computer system.
The command sent through the bus is picked up, the picked up command is sent to the virtual device driver manager, and the command is allocated by the virtual device driver manager to the virtual device driver specified by the logical unit number included in the command. A non-SC connected to the virtual device driver via the virtual device driver to which the command is assigned
An access method for a non-SCSI device, characterized in that an SI device is accessed in accordance with an allocated command.