JPS6313623B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control station device, particularly a data highway that is located between a data highway and an information processing device connected to the data highway and controls data communication between the two. control station device.

Generally, a control station device receives a received frame in a predetermined format from a data highway, and sends received data included in this received frame to an information processing device.

FIG. 1 is a format explanatory diagram showing an example of a frame format of a received frame received by the present invention and a conventional control station device. The frame format 15 is composed of a control section 16 and a data section 17, and the control section 16 includes a data length field 18 indicating the data length of the received data constituting the data section 17.

Therefore, the control station device is
When a received frame is received, storage control of the received data and transfer control of the information processing device are performed according to the data length indicated by the data length field 18.

A conventional control station device includes an input buffer for storing received data included in a received frame received from a data highway, and an information processing device for transmitting the received data stored in the input buffer each time the received frame is received. It is configured to include an input/output control section for sending out data.

An example of a conventional control station device will be described below with reference to the drawings.

FIG. 2 is a block diagram showing an example of a conventional control station device, which is equipped with one input/output buffer for transmitting and receiving data, and transmitting and receiving data to and from an information processing device, respectively. They were placed one by one in the buffer and sent and received from the data highway.

In the figure, reference numeral 1 indicates a control station device, and its configuration includes an input/output control unit 3 that controls an interface with a data highway 2, an input data buffer 4, and an input/output unit connected to an interface cable 6 with an information processing device 5. It consists of a control section 7, an output data buffer 8, and a common control section 9.

By the way, the data received from the data highway 2 includes, in addition to long data as general information sent from other control station devices,
There is short data such as normal reception notification and non-reception notification, but like long data, this short data is also stored in the input data buffer 4 of the control station device 1 and sent to the information processing device 5 each time.

Therefore, in the information processing device 5 serving as the host, the number of times the short data is received increases, which increases the load on the information processing device 5.

In addition, in a system in which a large number of real-time processing minicomputers, factory terminals, etc. are connected to the data highway 2, short data from these devices is continuously generated and sent to the control station device 1. , the information processing device 5 may not be able to receive it in time, and short data may be dropped.

That is, the conventional control station apparatus has a drawback in that the number of times received data is sent to the information processing apparatus is large.

An object of the present invention is to provide a control station device that can reduce the number of times received data is sent to an information processing device.

That is, an object of the present invention is to resolve the above drawbacks by determining long data and short data and storing short data in a control station until it reaches a specified number, thereby reducing the number of times an information processing device receives data. An object of the present invention is to provide a control station device that can prevent data from being dropped.

When the control station device of the present invention receives a receive frame consisting of a data section and a data length field indicating the data length of this data section from a data highway, the control station device determines whether the data length is longer than a predetermined length or not. a first input data buffer that stores long data when the determination result indicates that the data is long data; and a first input data buffer that stores the long data when the determination result indicates that the data is short data. a second input data buffer that cumulatively stores the short data when the determination result indicates that the data is short; and a second input data buffer that cumulatively counts the data length when the determination result indicates that the data is short and the cumulative value exceeds a predetermined value. a counter that generates a count over signal when the count over signal is reached; and a counter that generates a count over signal when the count over signal is generated; , an input/output control unit that outputs to the information processing device, and an input/output control unit that outputs to the information processing device.

That is, the control station device of the present invention is a control station device for a data highway that is located between a data highway and an information processing device connected to the data highway and transfers data between the two. In addition to the first input data buffer for storing long data transmitted from the highway, a second input data buffer for storing short data is provided, and when data is received from the data highway, it is determined whether the data is long data or short data. The long data is stored in the first input data buffer and the short data is stored in the second input buffer, the long data is sent to the information processing device each time it is received, and the short data is accumulated and specified. The second input buffer is configured to send the data to the information processing device only when data having a data length of 1000 is stored in the second input buffer.

That is, the control station device of the present invention has a first input data buffer for storing long data and a second input data buffer for storing short data.
an input data buffer, and a buffer control unit that controls these two input data buffers,
Long data and short data from the data highway are judged by a judgment circuit and input into respective input buffers, and when the counter of the buffer control section counts the data length of the short data to a specified number, the accumulated short data is buffered. The second input buffer is configured to have a mechanism for sending data from the second input buffer to the information processing device according to instructions from the section.

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 3 is a block diagram showing an embodiment of the present invention, in which the control station device 1' includes a determination circuit 12 for determining the length of received data from the data highway 2, and a determination circuit 12 for determining the length of data received from the data highway 2, and for storing the length data after determination. An input data buffer 10 for storing short data after determination, an input data buffer 11 for storing short data after determination, and a counter 13 for controlling the two input data buffers and accumulating and counting the data length of the short data stored in the input data buffer 11. It is configured to include a control section 14. The other parts are the same as those shown in FIG.

Next, the operation of transmitting short data to the information processing device 5 will be described.

Received data from the data highway 2 is received by an input/output control section 3 for the data highway.
The frame format of the received frame is configured as explained in FIG.

Therefore, if the data length shown in the data length field 18 is less than a certain value (for example, 8 bytes), it is considered short data, and if it exceeds that value (for example, 9 bytes or more), it is considered long data. A reception frame received by the input/output control unit 3 is determined by a determination circuit 12 for determining the data length as to whether it is long data or short data, and is input into the corresponding input data buffer. If it is determined that the data is short data, the counter 13 of the buffer control section 14 is counted up by the data length, and the short data is input into the input data buffer 11.

The end mark indicating the end of the data stored in the input data buffer 11 is placed at the address immediately after the newly accumulated short data, with the previous end mark erased every time new short data is stored.

When the counter 13 in the buffer control unit 14 reaches or exceeds a specified number (for example, 57 bytes if the input data buffer 11 has a capacity of 64 bytes), a count over signal is generated and the buffer control unit 14 immediately inputs the data. The short data accumulated up to the end mark is transmitted to the information processing device 5 through the output control section 7.

By adding a second input data buffer and a counter, the control station device of the present invention cumulatively stores short data, and when the cumulative value of the data length exceeds a predetermined value, the cumulatively stored short data is stored all at once. Since the received data can be sent to the information processing device after receiving the received data, the number of times the received data is sent out can be reduced.

That is, the control station device of the present invention can greatly reduce the number of times the short data is transmitted to the information processing device by accumulating and storing the short data in the input data buffer until the counter counts out, and the short data can be stored in the input data buffer until the counter counts out. Since it can be temporarily stored in an input data buffer separate from the data, it has the effect of preventing short data from being dropped.

[Brief explanation of the drawing]

FIG. 1 is a format explanatory diagram showing an example of a frame format of a received frame received by the present invention and a conventional control station device, FIG. 2 is a schematic block diagram including an example of a conventional control station device, and FIG. 3 1 is a block diagram containing one embodiment of the present invention; FIG. 1, 1'...control station device, 2
...data highway, 3...input/output control unit, 4...input data buffer, 5...information processing device, 6...interface cable, 7...input/output control unit, 8...output data buffer, 9...common control unit, 10...input data buffer , 11...input data buffer, 1
2... Judgment circuit, 13... Counter, 14... Buffer control section, 15... Frame format, 16... Control section, 17... Data section, 18... Data length field.

Claims (1)

[Claims] 1 When a received frame consisting of a data section and a data length field indicating the data length of this data section is received from the data highway, it is determined whether the data is long data or short data based on whether the data length is greater than or equal to a predetermined length. a first input data buffer that stores the long data when the determination result indicates that the data is long; and a first input data buffer that stores the long data when the determination result indicates that the data is short; a second input data buffer that cumulatively stores the short data; and a count over signal when the data length is cumulatively counted when the determination result indicates that the data is short data, and the cumulative value exceeds a predetermined value. a counter that outputs the stored long data to the information processing device when the determination result indicates that the data is long data, and short data that is cumulatively stored when the count over signal is generated. What is claimed is: 1. A control station device comprising: an input/output control section that outputs the information to an information processing device.