JPH0377159A - Station adaptor - Google Patents

Abstract

PURPOSE:To prevent a station connected to a station adaptor from joining the handshake with another station by separating the adaptor connected station form a bus transmission line when this station performs no transmission of data. CONSTITUTION:In a picture data generating device 12-1, the parallel data are transmitted via a bus 10 and the address of the device 12-1 is stored at an address setting part 14. Then a switch control part 16 decides whether the device 12-1 performs the transmission of parallel data or not based on the address stored at the part 14 and the data on the line 10. If not, the device 12-1 is separated from the line 10 via a switch part 18. As a result, the device (connection station) 12-1 which is not related with the transmission of data to another station never joins the handshake with another station.

Description

[Detailed Description of the Invention] [Summary] Regarding a station adapter that is inserted and connected between a station where parallel data transmission is performed using a handshake method and a bus transmission line used for that data transmission, the configuration of the connected station is described. The purpose of this project is to provide a station adapter that makes it possible to avoid slowdowns in data transfer between other stations without changing the address of a station where parallel data transmission is carried out using a handshake method via a bus transmission path. means for storing, means for determining whether or not the station transmits parallel data based on the storage address and data on the bus transmission path, and disconnecting the station from the bus transmission path when the station does not transmit parallel data. Consists of means and.

[Industrial Application Field] The present invention relates to a station 7 doubler that is inserted and connected between a station where parallel data transmission is performed using a handshake method and a bus transmission line used for the data transmission.

In systems that are composed of many devices and require efficient and reliable high-speed data transmission between these devices, these devices are connected via a bus transmission path such as GP-IB, and the devices are connected in parallel using a handshake method. Transfer of data occurs between devices.

[Prior Art] The system shown in 4th ryJ includes an image data generating device 12-1, such as a CT. Data processing devices such as personal computers! 2-2. Image processing device 12-3
They are connected by a bus transmission line 10.

In this system, image data obtained by an image data generation device 12-1 is transmitted via a bus transmission line 10 to a data processing device 12-2 using a handshake method, subjected to predetermined processing, and temporarily stored. It will be done.

The image data stored in the data processing device 12-2 is transmitted to the image processing device I2-3 via the bus transmission line 10 in a handshake manner, and display using this data is performed.
Recording and the like are performed by the image processing device 12-3.

When the above data transmission is performed according to the GP-rB interface specifications, the data is performed in units of 1 byte, and 1
Every time a byte of data is transmitted, reception is confirmed by handshaking.

As a result, data can be transmitted at high speed and reliably.

[Problem to be Solved by the Invention] When data is received by two or more devices, reception is confirmed by all of these devices (listeners) before the transmission source device (talker) transmits the next data. is sent.

Therefore, the data transmission rate of the system is limited by the least capable device.

In the system shown in FIG.
-2 and the image processing device 12-3, and the data processing device 12-2. During data transmission between the image processing devices 12-3, the image data generation device 12-1 has low capability.
Since the data processing device 12-2 performs handshake with the talker's data processing device 12-2, the data transfer rate at that time is also extremely low.

The present invention has been made in view of the above-mentioned conventional circumstances,
The purpose is to provide a station adapter that makes it possible to avoid a reduction in the speed of data transfer between other stations without changing the configuration of the connected stations.

[Means for Solving the Problems] In order to achieve the above object, the station adapter according to the present invention is configured as follows.

In the station 12-1 (image data generation device) in the figure, parallel data transmission is performed via the bus transmission line 10, and the station 12-1 (image data generation device)
The address of 2-1 is stored in means 14 (address setting section).

The means 16 (switch control section) then determines whether or not the station 12-1 transmits parallel data, and this determination is made using the storage address of the means 14 and the data on the bus transmission line 10. ing.

When the means 16 determines that the station 12-1 does not transmit parallel data, the station 12-1 is disconnected from the bus transmission line 10 by the means 18 (switch unit).

[Operation] In the present invention, since the connected station 12-1 is disconnected from the bus transmission path 1o when not transmitting data, the data transmission between other stations (12-2, 12-3) is interrupted. The connecting station 12-1, which is in direct contact with this station, does not participate in the handshake between these other stations.

[Embodiment] Hereinafter, a preferred embodiment of the station adapter according to the present invention will be described based on the drawings.

FIG. 1 shows an example of a station adapter 1 to which the present invention is applied, and as can be understood from FIG. It is inserted between the generator 12-1 and the bus transmission line 10.

The configuration of the image data generator 12-1 is the same as that in FIG. 4, and the station adapter 1 is an independent device with a separate power supply from the image data generator 12-1. ing.

In FIG. 1, the station adapter 1 includes an address setting section 14.
Switch control section 16. The switch control unit 16 includes a command mode detection unit 16a, a listener address detection unit 16b, a listener address comparison unit 16, an unlisten detection unit 16d, and a switch control unit 16.
Flip-flop 16e, OR circuit 16f, 16g
, )-address detection section 16h.

A talker address comparison section 16i is provided.

Further, as shown in the figure, the bus transmission line 10 includes data iJ,
10m, a control line 10b, and a handshake line 10c.

When transmitting data, the control line 10b is
A command mode is set in advance as shown in B), and during this command mode, a talker address and a listener address are sent to the data line 10a in a time-division manner.

In the station adapter 1, the command mode detection section 16a of the switch control section 16 controls the selection of the command mode &! It is detected by monitoring the job, and its output is given to the listener address detection section 16b.

As a result, the listener address detecting section 16b detects the listener address from the data K10a, and the detected address is given to the listener address comparing section 16c.

The station address set by the address setting section 14 is given to the listener address comparison section 16c, and the station address of the image data generation device 12-1 is set in advance in the address setting section 14.

Therefore, when the detected address given from the listener address detection section 16b and the set address of the address setting section 14 match (that is, when the image data generation device 12-1 is designated as a listener), the listener address comparison section 1
6c, a matching comparison output is obtained.

This comparison output passes through an OR circuit 16g and is given to the set input of a flip-flop 16e.
The output of e is given to the switch section 18 via an OR circuit 16f.

As a result, handshake &! 10c is closed, and the data processing device 12-2 or image processing device 12-3 of the talker connects the data line of the bus transmission line 10 to the third
The data sent out as shown in Figure (A) is received by the image data generating device 12-1.

Note that the detection output of the command mode detection section 16a is given to the OR circuit 16f, so that the NACK line of the handshake line 10C is closed in advance when the command mode is detected.

The detection output of the command mode detection section 16a is also given to the unlisten detection section 16d, and when the command mode detection section 16& detects the command mode, the unlisten signal (all listener specified is released) is detected by the unlisten detection section 16d, and the flip-flop 16e is reset by its output.

Here, if the image data generating device 12-1 is not designated as a listener and the data mode shown in FIG. 3(B) in which data is transmitted as shown in FIG. 3(A) is selected, , the set output of the flip-flop 16e is not obtained, and the detection output of the command mode detection section 16a is also not obtained.

Therefore, these outputs are not given to the switch unit 18 via the OR circuit 16f, and T1 of the handshake line 10c becomes open.

Therefore, during data transmission in which the data processing device 12-2 becomes the talker and the image processing bag R12-3 becomes the listener, the image data generation device 12-1, which has a lower capability in terms of data transmission speed, is used as the communication between the two. It does not participate in the handshake.

The explanation so far has focused on detecting the listener address, but even when the own station is designated as a talker, it is necessary to connect the NACK line 10c for transmission handshake.

As in the case of specifying the listener, the talker address detection section 16h
and a talker address comparison unit 16 into which the own station address is input.
The output of i, the output of the listener address comparator 16C, and the OR circuit lag are logically summed and the flip-flop 1 is
Set 6e.

As a result, even if the own station is designated as a talker, the switch unit 1
8 is closed, the image data generating device 12-1 is logically connected to the bus, and data transmission to other stations becomes possible. The connection to the bus is established and transmission is performed normally.

As explained above, according to this embodiment, the adapter connection station (device 12-1) with low data transmission speed capability is connected to another station (device 12-1).
Since the adapter-connected station is disconnected from the bus transmission line 10 when data transmission is performed between the devices 12-2 and 12-3), the adapter-connected station does not participate in handshaking between other stations.

Therefore, high-speed data transmission can be performed only between other stations.

Further, according to this embodiment, there is no need to change the configuration of the adapter-connected station, and sufficient transmission speed can be obtained by connecting this station adapter only to stations whose capabilities are extremely low in terms of transmission speed. It becomes possible to construct a system that can perform high-speed data transmission between stations extremely easily and at low cost.

Note that even if the adapter-connected station is capable of high-speed data transmission, the intervening reception confirmation is always omitted, making it possible to further speed up data transfer between other stations.

[Effects of the Invention] As explained above, according to the present invention, when the station connected to the station adapter is not transmitting data, it is disconnected from the bus transmission path, and therefore, the station connected to the adapter is disconnected from the bus transmission path. It does not participate in the handshake.

Furthermore, it can be used as is without changing the configuration of the station.

As a result, it becomes possible to easily and inexpensively construct a system in which data transmission between stations is performed at high speed.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the configuration of the embodiment, 'I42 is a connection explanatory diagram of the embodiment, FIG. 3 is an explanatory diagram of the operation of the embodiment, Figure 4 is an explanatory diagram of the prior art; It is. ...station adapter 0...Bus transmission line Oa...data line ob… system &lli&! Oc...handshake line 2-1... Image data generator 2-2...Data processing device 2-3... Image processing device 4...Address setting section 6...Switch control section 6a...Command mode detection section 6b...Listener address detection section 16c ・ 16e ・ 16f ・ 16g dispute 16h ・ 16j ・ 8-- ・Listener address comparison section ·flip flop ・OR circuit ・OR circuit ・Talker address detection section ・Talker address comparison section Switch part Example connection diagram Figure 2 No. figure

Claims (1)

[Claims] Means (14) for storing an address of a station (12-1) in which parallel data transmission is performed via a bus transmission line (10) in a handshake manner; means (16) for determining whether or not to transmit data based on the storage address and data on the bus transmission line (10); -1) from the bus transmission line (10);