JPH03101332A - Transmission controller - Google Patents

Abstract

PURPOSE:To accurately recognize the time when generated frame data is transmitted to a transmission line by always informing a data processor of the message of 'transmission termination' when the transmission of transmission data transferred from the data processor to the transmission line is terminated. CONSTITUTION:A transmission controller 3 generates a serial data frame from data transferred from the data processor 4, recognizes that the transmission line 1 is in an idle state and starts transmission to the transmission line 1. When the termination of transmission is detected, an informing means 7 immediately informs the data processor 4 of data showing 'transmission termination' by using a data bus 5 and a timing signal line 6. Thus, the data processor 4 can obtain information of the frame transmission timing of the transmission line and the time when generated frame data is transmitted to the transmission line can accurately be recognized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a transmission control device that controls data transmission in a home bus system or the like.

[Conventional technology]

The edge of information technology in recent years has also appeared in household equipment in the form of ``home bus systems''.

The basic component of the home bus system, the transmission system mLB, was announced at the Kansai Electronic Industry Promotion Center in 1981, and then in September 1988, K
(1! Wave Association Joint HBS Standards Committee) K led to the establishment of domestic standards for ``home bus systems''.

Figure 5, for example, was published by the Kansai Electronic Industry Promotion Center EIBEI Study Group on March 1, 1980.
In Figure 5, which is a block diagram of a conventional data transmission device shown in ``K1n0-HB B V 1.1 Baseband Transmission Control L8 Engineering'', (1) is the transmission path, and all information between each terminal is Data is transmitted and received via this transmission path (1). (2) is a terminal, and each terminal is a transmission path [1]
It is connected to the. (3) is a transmission control device that is installed in this terminal (2) and controls the transmission of data; 14) is the data that is received via the transmission path (1) and the transmission control device (3); or e terminal 1! It is a data processing device that has the function of generating data to be transmitted to the data bus (5).
and a timing signal line (6) that controls the timing of data exchange.

Here, data transmitted on the transmission path (1) will be explained. FIG. 6 is a frame configuration diagram showing the frame configuration of data transmitted to the transmission path (1).

In the figure, (IG is priority code PR, ([11 is self address SA, f12 is destination address DA, fi3 is control code)"C!O, (14i data length code BC, (1
9 is a data portion DATAn, and αe is a frame check code FCC.

The above codes are the contents of the transmission frame.

If this frame is addressed to an individual terminal.

A from the other party's terminal after a certain period of time after sending yacai.
CK/NAKαη is returned. The frame transmission destination is determined in the individual/broadcast distinction PR (I is also DATACII).

FIG. 7 is a flowchart showing the operation when the conventional transmission control device shown in FIG. 5 performs transmission. When the transmission control device (3) receives the transmission data from the data processing device (4), it determines that there is a data transmission request from the data processing device (14), and after confirming that the transmission path fil is in a communicable state, One frame containing data is constructed and transmitted to the transmission path (1) (steps B1 and B2). If a collision with data transmitted from another terminal (2) is detected during transmission, the transmission process is stopped and transmission is restarted after a certain period of time (step B3), after transmitting one frame of data. , determines whether the transmitted data is addressed to an individual terminal or multiple terminals based on the contents of the transmitted data, and determines whether there is a request for an affirmative response from the other party (step B5). 5 Sending data is addressed to multiple terminals,
That is, in the case of simultaneous broadcasting or group circular broadcasting, an acknowledgment (hereinafter abbreviated as AOK) from the destination terminal 4 is not required.

The transmission is completed, a message "transmission completed" is sent to the data processing device (4), and the transmission operation is completed. If the transmitted data is addressed to an individual terminal, an AOK from the destination terminal is waited for (step BS).

If a code other than ACK is returned or there is no return, a retransmission operation is performed, and if an ACK is returned, it is determined that the data has been successfully transmitted to the destination terminal, and the data is The processing device 4K notifies the message "transmission complete" and ends the transmission (steps B5 to B7).

Therefore, in the conventional transmission control device, the period from receiving transmission data transfer from the data processing device to returning a "transmission complete" message may be as follows.

■ If the transmitted frame is a broadcast frame → Immediately after the frame has been transmitted once ■ If the transmitted frame is an individual frame and is normally received on the receiving side → Immediately after the frame is transmitted and an AOK is returned in response [Problem to be solved by the invention] As systems equipped with the above-mentioned terminals: 88 become widespread, communication system diagnostic equipment (protocol analyzers) for test@-maintenance and troubleshooting of the systems have become necessary. Comes.

An essential function of a protocol analyzer is the ability to know the transmission timing of frames on a transmission path. If this function is attempted to be achieved using the "transmission complete" notification function of a conventional transmission control device, the notification timing will change depending on whether the transmitted frame is addressed to an individual address or not. There was a problem in that it was not possible to know exactly when the process ended.

This invention was made to solve the above-mentioned problems, and it is an object of the present invention to enable a data processing device to obtain information on frame transmission timing on a transmission path.

[Means for Solving the Problems] The transmission control device according to the present invention is provided with a notification means that always notifies the data processing device when one frame transmission is completed.

[Effect]

The reporting means in this invention always transmits data indicating "end of transmission of one frame" to the data processing device, regardless of the type of transmitted frame and the presence or absence of a response.

[Embodiments of the invention]

An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a transmission control device according to an embodiment of the present invention. In FIG. 1, ft) is a transmission path, and (2) is a terminal I'm! (including a protocol analyzer in this embodiment), +3) is a transmission control device.

+41 is a data processing device (in this embodiment, it includes a data processing portion of a protocol analyzer), 15) is a data bus, and C6) is a timing signal line. Further, (7) is a reporting means which has the function of detecting the end of transmission of one frame in the transmission control value @13) and reporting this to the data processing device +41K. Further, FIG. 2 is a configuration diagram showing details of the data bus (5) and timing signal line (6) that connect between the transmission control device (3) and the data processing bag #14.

In FIG. 2, DO to D7 are data buses that transmit data bidirectionally. (6a) is a timing signal line TBY14. for frame synchronization during transmission. (6b) is the output buffer full signal line OB F, C60) is the input buffer full signal line P, (6dl is the output signal @AOK, (6e> is the strobe signal line EIT)
B.

(6f) IIi error status signal @EFtR.

Here, T [I Y N (6m) + OB F
(6b) S T B (de) is data processing bag #1
4)→Transmission control device (3) direction signal line, from F (60
), AOK (6d), and ERR (df) are the transmission control device (
This is a signal line from 3) to the data processing device (4).

Next, I will explain the nine works. FIGS. 3 and 4 are flowcharts showing the transmission operation of the transmission control device (3).

The data processing device (4) generates transmission data and transfers the transmission data to the transmission control device (3), and determines that a transmission request has occurred within the transmission control value fit (31).
Step At) The transmission control device (3) creates a serial data frame from the data transferred from the data processing device (4), and after confirming that the transmission path ( 1). If there is a collision during transmission, the process returns to step A2 (step A3).

If the transmission fe is completed without collision, that is, if the transmission up to the FCC stop bit is successfully transmitted, that is, if the end of transmission is detected, the 9 notification means ('l) immediately sends data indicating "end of sending oI". Data processing bag fi + using the data <S15) and timing signal @(6)
4) Notify K (step A5).

Although there are several possible methods for notifying the data processing device [4] that "one frame transmission has ended," a case using handshaking will be described here.

FIG. 4 is a flowchart showing the operation of the reporting means (7) when transmitting the message "one frame transmission completed" to the data processing device (4) using handshake. 9 reporting means (7
) first confirms that I B IF (5c) is "L", that is, that notification is possible (step A31).

After that, set the error status signal line meRR (6f) to "L".
5) is a tosit code (
For example, 01H) is set (step A33). Furthermore, set 8TB (6d) to ``L'' in step A3.
4).

Wait for response from data processing device (4) (step A35)
.

The data processing device (41 is the data from the reporting means (71)
Receive the transmission end code) and send IBII'(do) to "
H' and terminates the 9:09 report (step A36).

If notification is performed using the method described above, the data processing device and the transmission control device can be operated asynchronously.

In the above embodiment, a sequence using handshake is shown, but it is also possible to notify the transmission end timing even if a signal line for 9 notification is provided separately.

Through the above-described operations, the data processing device i 141 can accurately detect the time when frame data is sent. From this point on, ACK reception and the like are performed in the same manner as before.

〔Effect of the invention〕

In this way, the transmission control device according to the present invention is provided.

The data processing device is configured to always notify the data processing device of the “transmission completed” message when the transmission data transferred from the data processing device is finished being sent to the transmission path, so the data processing device can check whether the generated frame data is being transmitted. This has the advantage that it is possible to accurately know the time at which it was transmitted over the Internet.

[Brief explanation of drawings]

FIG. 1 is a block configuration diagram showing a transmission control device according to an embodiment of the present invention, and FIG. 2 is a configuration diagram showing connections between the transmission control device and a data processing device. FIG. 3 is a flowchart showing the operation of the notification means within the transmission control device, FIG. 4 is a flowchart showing details of the notification operation, FIG. 5 is a block diagram showing the configuration of the conventional transmission control device, and FIG. FIG. 6 is a flowchart showing the operation of a conventional transmission control device. FIG. 7 is a frame configuration diagram showing frame addition of data transmitted on a transmission path. In the figure, Ill is the transmission path, (2) is terminal J, r3+
14) is a transmission control device, 14) is a data processing device, (5) is a data processing device, (6) is a timing signal line, and (7) is a reporting means. The same reference numerals in each figure are the same or corresponding parts. shows.

Claims (1)

[Claims] A transmission control device that transmits data from a data processing device via a transmission path, detects the timing at which one frame of data transmission to the transmission path is completed, and constantly reports the timing to the data processing device. A transmission control device characterized by comprising means.