JPH01286550A - Interface system - Google Patents

Abstract

PURPOSE:To relieve the load on the software of a communication processor and to send information surely with less number of components by discriminating whether or not the sent information is received by the receiver side every time a communication processor at the sender side sends the information of a prescribed length. CONSTITUTION:Two communication processors 101a, 101b make mutual communication. Then an interface device 110 is provided with a storage means 111 storing the information of prescribed quantity received/sent between the communication processors 101a, 101b and a communication control means 112 discriminating whether or not the information of prescribed quantity stored in the storage means 111 is already read to control the communication between the communication processors 101a, 101b. Thus, every time one communication processor at the sender sends prescribed amount of information, whether or not the other communication processor 101 of the receiver side receives the prescribed amount of information is discriminated. Then the load of the software of the communication processor is relieved and sure communication is attained with less number of components.

Description

[Detailed Description of the Invention] [Table of Contents] Overview Industrial Application Fields Conventional Technology Problems to be Solved by the Invention Means for Solving the Problems Action Examples ■, Correspondence between the Examples and FIG. 1 ■ , Configuration of the embodiment (i) Overall configuration (ii) Modem configuration (ji) DBU configuration (iv) Interface device configuration (iv-1) Bidirectional transceiver configuration ■, Operation of the embodiment (i) Operation of the interface device (ii) Overall operation (ii-1) Operation of the transmitting side (ii-2) Operation of the receiving side Regarding the interface method for controlling communication between processing devices, the purpose is to reduce the burden on the software on the communication processing device side and to perform reliable communication with a small number of components. 2. A storage means for storing a predetermined amount of information exchanged between two communication processing devices; and a communication control means for determining whether the predetermined amount of information stored in the storage means has already been read. An interface device is provided for controlling communication between two communication processing devices, and each time one of the communication processing devices on the sending side transmits a predetermined amount of information, the other communication processing device on the receiving side transmits the predetermined amount of information. The apparatus is configured to determine whether or not information has been received.

[Industrial application field]

The present invention relates to an interface method for a communication system,
In particular, it reduces the burden on the software on the communication processing device side,
This invention relates to an interface system that allows reliable communication with a small number of components.

[Prior Art] For example, a communication system that performs communication through a dedicated line is equipped with a dial backup device (DBLI) that backs up the line using an emergency dial line when a failure occurs in the dedicated line. Normally, this DBU exchanges information such as commands and data with a modem that modulates and demodulates communication, and communicates through a dial line.

Data exchange between the modem and the DBU requires a parallel-to-serial (P/S) converter that converts parallel data from the modem into serial data and serial data from the DBU into parallel data. It is controlled by an interface device equipped with a FIFO circuit that holds several bytes of parallel data from the modem or DBU and transfers it to the receiving side in the order in which it was written.

Here, since the communication between the modem and DBU is not one-way, the transmission line connecting the modem and DBU allows for the transmission of commands and data from the modem to the DBU, and the transmission of responses and data from the DBU to the modem. It is necessary to perform exclusive control of the right to use the interface device between the modem and the DBU so that these events do not occur at the same time.

[Problems to be Solved by the Invention] By the way, in the interface device equipped with the above-mentioned P/S converter, the 4 communication speed is determined by the processing speed of the P/S converter, so it depends on the processing state of the modem and DBU. Unable to adapt communication speed. On the other hand, an interface device equipped with a FIFO circuit can handle several bytes of data at once, but since the FIFO circuit is relatively expensive, it becomes a high-cost device.
In the system using the two types of interface devices mentioned above, exclusive control of the interface devices is performed entirely by the modem and DBU software.
There is a problem in that the burden on the software of the modem and DBU increases.

The present invention was created in view of these points, and provides an interface method that reduces the burden on the software of communication processing devices such as modems and DBUs, and enables reliable communication with a small number of components. is intended to provide.

[Means for Solving the Problems] FIG. 1 is a block diagram of the principle of the interface system of the present invention.

In the figure, two communication processing devices 101a and 101b communicate with each other.

The interface device 110 includes a communication processing device 101a,
storage means 111 for storing a predetermined amount of information exchanged between the devices 101b; It has communication control means 112 that determines whether a predetermined amount of information stored in storage means 111 has already been read, and controls communication between communication processing devices 101a and 101b.

Therefore, as a whole, one communication processing device 10 on the transmitting side
1 transmits a predetermined amount of information, the other communication processing device 101 on the receiving side determines whether or not it has received the predetermined amount of information.

[For production]

For example, when transmitting information from one communication processing device 101a to the other communication processing device 101b, communication processing device 1
When 01a writes a predetermined amount of information into the storage means 111,
The communication control means 112 notifies the communication processing device 101a that there is information in the storage means 111 that has not been completely read, and prohibits writing of the next information. Storage means 11
When the information stored in the communication processing device 101b is read by the communication processing device 101b and the communication control means 112 notifies that the reading of the information is completed, the communication processing device 10
In step 1a, the following predetermined amount of information is written.

Similarly, the interface device 110 controls the transmission of information from the communication processing device 101b to the communication processing device 101a.

In the present invention, the storage means 111 stores information for each predetermined amount.
and the communication processing device 101 on the receiving side stores it in the storage means 1.
Since the communication processing device 101 on the transmitting side writes the next information after the information written in the communication device 11 is read, the information is reliably transmitted.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 2 shows the configuration of a communication system using an interface method according to an embodiment of the present invention.

Correspondence between the Llii example and FIG. 1 Here, the correspondence between the embodiment of the present invention and FIG. 1 will be shown.

The communication processing device 101a corresponds to the modem 201.

The communication processing device 101b includes a dial backup device (
DBU) 202.

The interface device 110 is the interface device 21
Corresponds to 0.

Storage means 111 corresponds to bidirectional transceiver 211.

The communication control means 112 includes flip-flops 213a, 2
Corresponds to 13b.

Examples of the present invention will be described below assuming that the correspondence relationship as described above exists.

In FIG. 2, the communication system of the embodiment includes a modem 201 that modulates and demodulates communications through a dedicated line, and a dial backup device f that backs up the line by using an emergency dial line in the event that a failure occurs in the dedicated line. (DBU) 202, modem 201 and DBU20
2, and an interface device 210 that controls communication between the two.

(ii) Modem configuration The modem 201 has an input/output port (Ilo) for inputting/outputting 1 byte data, and outputs a read strobe signal Sra synchronized with reading data from the output terminal o1 to the I10 port. Output and also output terminal 02
It is configured to output a write strobe signal Swa in synchronization with writing from to the I10 port.

Furthermore, communication with the DBU 202 is determined by the states of the transmission status flag a, which indicates whether the transmission to the DBU 202 has been read, and the reception status flag a, which indicates whether the data from the DBU 202 has been written to the bidirectional transceiver 211. configured to determine the condition. For example, if the transmission status flag a is "0", it is determined that the reading of the transmitted data has been completed, and if it is "1", it is determined that the reading has not been completed. If the reception status flag a is "0", it is determined that there is no data in the bidirectional transceiver 211, and if it is "'1", it is determined that there is data.

(iii) DBU configuration BU202 has an input/output port (Ilo) port that inputs and outputs 1-byte data, and outputs a read strobe signal Srb synchronized with reading data from the I10 port from the output terminal OI. and from output terminal 02 to I1
It is configured to output a write strobe signal Swb synchronized with writing to the 0 port.

Also, depending on the state of the transmission status flag b indicating whether the transmission to the modem 201 has been read or not and the reception status flag b indicating whether the data from the modem 201 has been written to the bidirectional transceiver 211, the modem 201 is configured to determine the state of communication with 201. For example, if the transmission status flag b is '0', it is determined that the reading of the transmitted data has been completed, and if it is '1', it is determined that the reading has not been completed.The reception status flag b is '0'. ”
If so, it is determined that there is no data in the bidirectional transceiver 211, and if it is "1°", it is determined that there is data.

(iv) Configuration of interface device The interface device 210 includes a modem 201゜DBU2
Bidirectional transceiver 21 storing data from 02
1 and the write strobe signals Swa and D of the modem 201
A flip-flop 213a determines whether reading of data from the bidirectional transceiver 211 is completed based on the read strobe signal Srb of the BU 202 and outputs a read completion signal Sca; Based on the read strobe signal Sra, it is determined whether reading of data from the bidirectional transceiver 211 is completed, and a read completion signal S is generated.
It is formed by a flip-flop 213b that outputs cb.

(iv-1) Configuration of bidirectional transceiver The bidirectional transceiver 211 has an I10 port a to which the modem 201 writes and reads 1 byte data, and a D
The BU 202 has a port (10) b for writing and reading 1 byte of data, and the write strobe signal Swa of the modem 201 input to the I10 port a is synchronized with the write strobe signal Swa of the modem 201 input to the input terminal (2). DB that reads and stores data and inputs it to input terminal ■3
I1 in synchronization with the write strobe signal Swb of U202.
It is configured to read and store data from the DBU 202 that is input to the DBU 202.

Also, in synchronization with the read strobe signal Sra input to the input terminal I2, the data of the I10 port a is determined, and the read strobe signal Sra input to the input terminal I4
In synchronization with b, the data of I10 port b is determined.

LJL! Operation of the J Can Example FIG. 3 is a timing diagram illustrating the operation of the communication system according to the embodiment shown in FIG.

FIG. 4 is a flow chart showing the operation of the communication system according to the embodiment shown in FIG.

The operation of the embodiment will be described below with reference to FIGS. 2 to 4, taking as an example the case where communication is performed from the modem 201 to the DBU 202.

(i) Operation of the interface device The write strobe signal Swa (see Figure 3 ■) that the modem 201 outputs in synchronization with data writing to the I10 port is sent to the bidirectional transceiver 211 input terminal ■2.
is input to the clock terminal CK of the flip-flop 213a. At the rising edge of the write strobe signal Swa, the flip-flop 213a sets the output terminal Q to "1", and the read completion signal 5ca (see Figure 3) becomes "1".
Output.

In response to this read completion signal Sca, the modem 201's transmission status flag a (see Figure 3 ■) and the DBU 202's reception status flag b (see Figure 3 ■) are set, and the modem 201 writes the data to the bidirectional transceiver 211. indicates that the data has not yet been read.

A read strobe signal 5rb (see 3 in FIG. 3) output when the DBU 202 reads data input to the I10 port is input to the bidirectional transceiver 211 and the clear terminal CLR of the flip-flop 213a.

As a result, the flip-flop 213a is cleared and outputs "O" from the output terminal Q as the read completion signal Sca.

By this read completion signal Sca, the transmission status flag a of the modem 201 and the reception status flag b of the DBU 202 are cleared to "0", indicating that the data written in the bidirectional transceiver 211 by the modem 201 has been read. .

In the same manner as described above, when the DBU 202 becomes the transmitting side and sends data to the modem 201, the output of the flip-flop 213b is set to 1 by the write strobe signal Swb (■ in Figure 3) of the DBU 202, and the modem The output of the flip-flop 213b is cleared by the read strobe signal 5ra (■ in FIG. 3) of the flip-flop 201.

Reading completion signal 5 which is the output of the flip-flop 213b
cb (Fig. 3 ■)) sets and clears the modem 201's reception status flag a (Fig. 3 ■) and the DBU 202's transmission status flag b (Fig. 3 @)).
Indicates whether the data written by U202 to bidirectional transceiver 211 has already been read.

” ■ Masukura body ■ Kisho Below, the operation of the entire communication system will be explained by dividing it into the transmitting side and the receiving side.

(ii-1) Operation on the Transmitting Side First, the modem 201 checks whether there is any data remaining in the bidirectional transceiver 211 to be read by the modem 201, based on the reception status flag a (step 401).

In step 401, if the reception status flag a is "1", it is determined that the transmission process cannot be continued because the transmission from the DBU 202 to the modem 201 has not yet been completed, and the transmission from the modem 201 to the DBU 202 is terminated. Finish the process.

If the reception status flag a is "0" in step 401, the modem 201 checks the transmission status flag a (step 402).

Here, in step 402, the transmission status flag a is set to “
If the loop that occurs when "1" is set continues for more than a predetermined time (for example, 200IIs), DBU20
It is determined that a failure has occurred in No. 2, and the transmission process is terminated.

The modem 201 outputs 1 byte of data to the I10 port, and also outputs a write strobe signal Swa.
Write 1 byte of data to bidirectional transceiver 211. At this time, a read completion signal Sca is output from the flip-flop 213a by the write strobe signal Sima, and the transmission state flag of the modem 201 and the DBU2
02 is set to "1" (step 403).

If there is still data to transmit, the process returns to step 402 (step 404).

Repeating steps 402 to 404, modem 201 transmits data one byte at a time, and after confirming that the transmitted data has been received, transmits the next data to DBU 202.

(ii-2) Default operation The DBU 202 reads the reception status flag b to check whether data from the modem 201 has been written to the bidirectional transceiver 211 (step 411).

In step 411, if the reception status flag b is "1", the DBU 202
11, the DBU 202 determines that the data to be read is stored in the I10 port, outputs a read strobe signal Srb, and sends the data from the bidirectional transceiver 211 to the I10 port.
Read bytes of data. At this time, the read strobe signal Srb clears the transmission status flag a of the modem 201 and the reception status flag b of the DBU 202 (
step 412).

In this way, data communication is performed between the modem 201 and the DBU 202. The processing speed of this data communication does not depend on the performance of the bidirectional transceiver 211 of the interface device 210, but rather depends on the performance of the modem 201 and DBU.
The communication processing speed can be adjusted depending on the processing state of the modem 201 and the DBU 202.

(2) Summary of the Embodiment As described above, for example, if the modem 201 is the transmitting side and the DBU 202 is the receiving side, the flip-flop 213a
outputs “1” or “0” as the read completion signal Sca, and transmits the transmission status flag a of the modem 201 and the DBU 20.
Set reception status flag b of 2.

In this way, when it becomes the receiving side, it judges whether 1 byte of data to be received has been written to the bidirectional transceiver 211 based on each reception status flag, and on the other hand, when it becomes the sending side. In this case, it is possible to determine whether the data written to the bidirectional transceiver 211 has been read by the receiving side, depending on the respective transmission status flags.

This makes it possible to confirm that the data that the modem or DBU on the transmitting side writes and transmits one byte at a time to the bidirectional transceiver 211 has been received on the receiving side.

■1 Form of the invention In the embodiment of the invention described above, the modem and D
I thought of controlling communication based on the BU's write strobe signal and read strobe signal, but the modem and DB
It can be applied as long as it is not attached between the sender and the sender and that the receiver confirms that the information sent at intervals of a predetermined length is received by the receiver. Furthermore, the length of the information transmitted at each time is not limited.

Furthermore, in "■, Correspondence between Examples and FIG. 1",
Although the correspondence between the present invention and the embodiments has been described above, those skilled in the art can easily imagine that the present invention is not limited to this and that there are various modifications.

[Effects of the Invention] As described above, according to the present invention, each time the communication processing device on the transmitting side transmits information of a predetermined length, it is determined whether the transmitted information has been received by the receiving side. can do.

This makes it possible to reduce the burden on the software of the communication processing device and reliably transmit information using fewer components, which is extremely useful in practice.

[Brief explanation of the drawing]

Fig. 1 is a principle block diagram of the ink face method of the present invention, Fig. 2 is a configuration diagram of a communication system using an interface method according to an embodiment of the present invention, and Fig. 3 is a diagram according to the embodiment shown in Fig. 2. Timing Chart for Explaining Operation of Communication System FIG. 4 is a flowchart for explaining the operation of the communication system according to the embodiment shown in FIG. In the figure, 101 is a communication processing device, 110 is an interface device, 111 is a storage means, 112 is a communication control means, 201 is a modem, and 202 is a DBU. 210 is an interface device, 211 is a bidirectional transceiver, and 213 is a flip-flop. :. ■Go to the seat 4 theory

Claims (1)

[Claims] (1) Two communication processing devices (101
a, 101b) and a storage means (111) for storing a predetermined amount of information exchanged between the communication processing device (101a, 101b);
communication control means (112) for determining whether a predetermined amount of information stored in the storage means (111) has already been read;
), and controls communication between the communication processing devices (101a, 101b).
and, each time one communication processing device (101) on the sending side transmits a predetermined amount of information, the other communication processing device (101) on the receiving side receives the predetermined amount of information. An interface method characterized by being configured to determine.