JPH0415853A - Scsi device converter - Google Patents

Abstract

PURPOSE:To execute interruption from a peripheral device side by providing an interruption control part which once releases the line of EWS (engineering working station) when interruption data is not prepared and makes it possible to read data when interruption data is inputted. CONSTITUTION:This SCSI device converter 3 inputs/outputs data to/from the peripheral device 4-6 through device interfaces 8-10, converts the data into the data of SCSI specification by a code conversion part 15 and input/outputs it to data write parts and read parts 11-14. When the data is not prepared in an interruption data read part, the interruption control part 17 once releases the line of EWS by using the disconnecting signal and the reconnecting signal of SCSI specification to the read instruction of interruption data from EWS 1. When the data is prepared, the data is read. Thus, the SCSI interface 7 of EWS is allowed to execute a pseudo interruption operation and a device which requires interruption can be connected.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention is a general-purpose 5C3I device that allows devices such as personal computer peripherals and sequencers to be easily connected to the 5csr interface of an EWS (engineering workstation). Regarding converters.

[Problems to be solved by conventional technology and invention] EW
S is used for consumer use because it is capable of high-speed data processing with a relatively inexpensive equipment configuration due to multi-tasking and multi-window processing.

This EWS is a standard interface for SCs intended for connection with hard disks and magnetic tape drives.
Equipped with SI interface. However, it does not have an expansion board slot like a personal computer. Therefore, it was not possible to directly connect output devices such as the PC I10 bus, which is a PC-compatible bus, or a block with a bidirectional parallel bus with interrupts, a sequencer, etc. to the EWS. In other words, the current EWS only functions as an initiator. Because the converter does not have one, it is not possible to connect the line from the converter to the EWS.

Although personal computers have a high degree of freedom in connecting peripheral devices by using expansion slots, the processing speed is slow and is not practical because the processing is a single task.Furthermore, high-end EWSs require connection to peripheral devices. Some devices are equipped with a dedicated bus, but because they are targeted at specific devices, it is not possible to freely connect any device, making the system configuration very expensive.

If you want to connect a peripheral device with a PC-compatible bus to the EWS, you will need to convert the code between the standard SCSI interface, which is currently designed for hard disks, and the PC-compatible bus, such as a GPIB interface. All you have to do is create a code converter to connect.

However, current SCSI designed for hard disks
The interface did not have an interrupt function, and it was not possible to connect devices that required interrupts to the host side, such as sequencers.

Therefore, this invention was developed for the 5CSI interface of EWS, which is made for the purpose of connecting with hard disks.
To provide a general-purpose 5C3I device converter which can easily connect peripheral devices having a bus of a different standard from 5C3I, such as a bus compatible with a personal computer, and in particular can receive an interrupt from the peripheral device side.

[Means to solve the problem]

This invention provides a SCSI interface connected to a 5C8I interface for hard disk connection of an EWS (engineering workstation), a device interface for connecting to a peripheral device, and a different ID number or the same ID number from the EWS through the SCSI interface. A data writing section, a data reading section, a control data writing section, and an interrupt data reading section, which are recognized with different unit numbers based on ID numbers, are interposed between these data writing section and reading section, and the device interface, and the data a code conversion unit that mutually converts the data into the 5C3I type and the bus type of the peripheral device; a control unit that manages data transmission and reception between the EWS and the peripheral device, which is performed by relaying the data writing unit and reading unit; When interrupt data is not prepared in the interrupt data read section in response to an interrupt data read command sent from When interrupt data is input from the device to the interrupt data reading section, the reconnect signal (SCS
I standard) through the 5C5I interface.
An interrupt controller that sends the interrupt data to the WS and allows the EWS to read the interrupt data.
Provides a CSI device converter.

C action] The above SCSI device converter inputs and outputs data to and from the SCSI interface of the EWS according to the same standards as the SCSI interface for hard disks, and the EWS functions as a data relay station with peripheral devices. It is possible to arbitrarily write and read data to and from a data writing section and a data reading section.

In addition, this 5C5I device converter inputs and outputs data to and from peripheral devices according to the bus standard of the device through the device interface, and converts this data into data of the 5CSI standard by the code conversion section. It inputs and outputs four types of data to the write section and read section.

In response to an interrupt data read command from the EWS, the interrupt control unit temporarily releases the EWS line by using the SCSI standard disconnect signal and connect signal when no data is prepared in the interrupt data read unit. , and then read the data when it is ready.

This operation allows the SCSI interface of the EWS, which is not designed to allow interrupts from the device side, to perform superior interrupt operations, and allows devices that require interrupts to be connected to the SCSI interface of the EWS, which is designed for connecting hard disks. can.

〔Example〕

An example of a configuration in which peripheral devices are connected to an EWS using a 5C5I device converter according to an embodiment of the present invention will be described with reference to FIG.

In the figure, (1) is a relatively inexpensive EWS (engineering workstation) such as a desktop type, and the SCSI interface (2) for connecting the hard disk.
is included as standard equipment. (3) is a 5csI device converter built into one board, and the above EWS
Connected to (1) are peripheral devices such as an output device (4) such as a plotter, an input device (5) such as a CDROM, and a device (6) that performs interrupt control such as a sequencer.

The 5C3I device converter (3) has a SCSI interface (7) for connection with the EWS (1), and a personal computer I10 bus interface (8) (9) as a device interface for connecting peripheral devices.
) and bidirectional parallel bus interface with interrupts (
10), and this 5C3I device converter (3) has different ID numbers N, N+1,... through the EWS (1) to 5C8I interfaces (2) (7).
・N+3 (or same ID number but different unit number N,
N+1,...N+3), a data writing section (11), a data reading section (12), a control data writing section (13), an interrupt data reading section (14), and each data writing section and reading section. (11) (12) (13) (14) and device interface (8) (9) (10
), there is a code conversion unit (15) that mutually converts the data format between the 5CSI standard and the device interface bus standard, and the EWS and peripheral devices that relay the data writing and reading units. A control unit (16) that manages data transmission and reception, and an EWS (1)
In order to be able to accept interrupt signals from devices through the SCSI interfaces (2) and (7) without interrupting processing, an interrupt control unit (17) that generates control signals is connected to a microcomputer and a ROM. and RAM.

The device interface of this SCSI device converter (3) can also be used with other types of the above-mentioned I10 bus interfaces (8) and (9) and bidirectional parallel bus interface with interrupts (10). Can be adopted according to the requirements. For example, an A/D converter (19) may be built in so that analog data can be input from an analog device (18) such as a sensor. Here, the device interface may be R3-232, a standard interface such as Centronics or VME bus, or a dedicated interface such as an expansion bus of each personal computer.

The EWS device converter (3) having the above configuration operates as follows.

The SCSI interface of EWS (1) is designed to connect up to eight hard disks.

Therefore, in this invention, the EWS (1) has a good appearance, a data writing section (11), a data reading section (12)
, control data reading section (13) and interrupt data reading section (14), so that each writing section and reading section (11) ... (14) can be recognized as four hard disk devices among them. ID number (or unit number with the same ID number) (N, N+1,...
・N+3) is assigned. In other words, EWS (1
) simply performs a write or read operation on each write unit or read unit using the same procedure as for the four hard disks.

On the other hand, the control unit (16) controls the peripheral devices (4) and (5).
In contrast to (6), device interface (8)
(9) Controls data input/output through (10). That is, the data written in the data writing section (11) is outputted to an output device (4) such as a plotter,
Data read from an input device (5) such as a CD-ROM is input to a data reading section (12), and data written to a control data writing section (13) is sent to a device (6) that performs interrupt control such as a sequencer. Interrupt data from the device (6) that outputs and performs interrupt control is input to the interrupt data reading section (14). This input/output control of the control unit (17) is performed at a predetermined timing by interpreting commands sent from the EWS (1).
(9) (10) and each data write section and read section (11) (12) (13) (14
) A code conversion unit (15) intervenes in data transmission and reception between the SCSI standard and each bus standard, and performs code conversion between the SCSI standard and each bus standard. Also, device interfaces (8) (9) (
10), even if there are multiple channels, the code conversion unit (15), control unit (16), and interrupt control unit (17)
can be controlled by

In this invention, since the EWS (1) recognizes each writing section and reading section (11) (12) (13) (14) as separate devices, the EWS (1) recognizes each writing section and reading section (11) ( 12) (13
) For (14), different writing programs and reading programs are started at the same time and processed in parallel, resulting in high processing efficiency.

A major feature of this invention is that the 5C5I interface (2) of the EWS (1), which does not take into account interrupts from the device side, performs pseudo interrupts. That is, from the EWS (1) to the interrupt data reading section (14
), and if no interrupt data is prepared, the CD-ROM input device (5) is set to EWS (1). Unlike preparing data in response to read instructions from
) sends a disconnect signal to EWS (1) and
Temporarily release the WS line. This allows EWS (1)
can do other things. After this, when interrupt 12 data is prepared in the interrupt data reading section (14),
The interrupt control unit (17) sends a reconnect signal to the EWS (1). Upon receiving this, EWS (1) reads the interrupt data, and EWS (1) finishes reading the interrupt data.

The above operation will be explained in terms of the procedure on the SCSI driver (software) of EWS (1). EWS 5
The C3I driver is developed as a driver for connecting hard disks.

Therefore, the device of the present invention behaves like an emulation of this hard disk. This procedure is performed according to the flowchart shown in FIG.

In this flowchart, from 5tart to Mode 5e
nse is the hard disk initialization procedure, Inqu
iry reports target and logical unit attribute information (device type identification code), 5tar
t/5top Unit starts/stops the logical unit, Te5t Unit Ready tests the usability status of the logical unit, Mode 5e
nse is a report of various parameter values (data format, configuration of recording medium). As a result, each writing section and reading section (11) (12) (13) (1
4) becomes active for EWS (1).

After this initialization procedure, the EWS (1) has each writing part and reading part (11) (12) (13)
Execute writing or reading to (14). That is, Read Extended is read from the specified block, that is, the data reading unit (12) or the interrupt data reading unit (14), and Write Extended is
xtendnd is the specified block, that is, the data writing section (11) or the control data writing section (13).
).

Since the above procedure uses the SCSI standard, the device of the present invention can be used with EWS (1
) can be easily connected to the SCSI interface of

A procedure for controlling devices with various interfaces, such as those compatible with personal computers, using this standardized procedure will be explained. Control of various devices involves reading and writing to memory,
It is divided into writing commands and reading interrupt signals from the device. In the device of this invention, each function is divided into a writing section and a reading section (11) (12) (
13) Since the four units in (14) share the responsibility, both the writing and reading programs are activated at the same time in the EWS. Among these functions, reading of interrupt data is performed as shown in the flowchart shown in FIG. 3, and a pseudo-interrupt is caused by the SCSI interface, which does not take interrupts into consideration.

First, from the EWS, interrupt data reading section (14)
, the read command causes the output. This reading needs to be performed periodically in anticipation of the interval at which device interrupts occur. At this time, normally no interrupt data is prepared, so the interrupt control unit (17) sends a disconnect signal to the EWS (1), releases the line of the EWS (1), and enables other processing. do. Next, when an interrupt occurs in the device and the interrupt data is prepared, the interrupt control section (17) outputs a reconnect signal to the EWS (1), and the interrupt data reading section (17) outputs a reconnect signal to the EWS (1).
4) Read the interrupt data from. When the interrupt data has been sent to EWS (1), it means that EWS (1) has finished executing this read instruction.

〔Effect of the invention〕

According to the present invention, it is possible to easily connect a device having an interface that requires an interrupt to a SCSI interface of an EWS that does not take interrupts into consideration.

In addition, in this invention, four write sections and a read section are provided for reading and writing data from the EWS to the device, writing commands, and reading interrupt data, which are recognized as different logical devices. It can be started at the same time as the reading program, enabling high-speed processing.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a 5C3I device converter according to an embodiment of the present invention, which is connected between an EWS and a device;
FIG. 2 is a flowchart showing the operation procedure of the EWS in the connection shown in FIG. 1, and FIG. 3 is a flowchart showing the procedure for reading interrupt data in the configuration shown in FIG. (1)-EWS. (2) (7)-5C3I interface, (3)-5
C3I device converter, (4) (5) (6) - Peripheral device, (9') (10) - Device interface, data read section, data write section, control data write section, interrupt data read section, code Conversion section, control section, interrupt control section.

Claims (1)

[Claims] (1) EWS (Engineering Workstation)
A SCSI interface to be connected to the SCSI interface for connecting the hard disk, a device interface for connecting to peripheral devices, and a different I/O interface from the EWS through the SCSI interface.
A data writing unit and a data reading unit that are recognized by a D number (or a different unit number with the same ID number),
A control data writing section, an interrupt data reading section, and a code conversion section interposed between these data writing and reading sections and the device interface, and converting data between the SCSI format and the peripheral device bus format. and a control unit that manages data transmission and reception between the EWS and peripheral devices, which is carried out by relaying the data write and read parts, and a control unit that handles the interrupt data to the interrupt data read unit in response to an interrupt data read command sent from the EWS. When it is not ready, output a disconnect signal to the EWS through the SCSI interface to release the EWS line,
Thereafter, when interrupt data is input from the device to the interrupt data reading section, the interrupt control section sends a reconnect signal to the EWS through the SCSI interface to enable the EWS to read the interrupt data. SCSI device converter.