JPH02228842A - Communication system for home control system - Google Patents

Abstract

PURPOSE:To attain sure transmission and reception of a data by sending a reception reject frame to a sender terminal equipment from a buffer memory when a data is further sent to a terminal equipment whose reception reaches an allowable limit. CONSTITUTION:A telecontroller 1, a house keeping controller 2 and a room controller 3 as plural terminal equipments are connected through a common home bus 4. If a capacity of a buffer memory of a terminal equipment is occupied, when a data is received from other terminal equipment with higher transmission priority than the former terminal equipment, a reception reject frame is sent to the data sender to stop the transmission from the other terminal equipment. When the reception buffer is idle, a transmission enable frame is sent to the sender terminal equipment to allow the terminal equipment to send the data again. Thus, a disadvantage of the sent data overflowed from the buffer and lost without any compensation is avoided and the reliability of communication is enhanced.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a communication method for a home control system, and particularly to a communication system for a home control system in which a plurality of terminal devices such as a home telephone, a telecontroller, etc. are connected via a common home bus. Regarding transmission and reception methods.

[Prior art] Figure 3 shows, for example, the "Japan Electronics Industry Association/Radio Technology Association Project ET/2101 Home Bus System"<September 1988.
This figure shows the configuration of a conventional home control system published in the 2006 issue of

The multiple terminals include a telecontroller (1), a housekeeping controller (2), and a room controller (3).
) are connected via a common home bus (4). In the illustrated example, only three terminals are shown for convenience, but the present invention is not limited to this, and it is of course possible to provide a plurality of other terminals.

FIG. 4 shows the address table of each terminal published in the above document, for example, the telecontroller (1) is 04H, the housekeeping controller (2) is 02H, room,
The address of each controller (3) is set as 06H.

FIG. 5 shows the format of a frame transmitted on the home bus, which is also published in the above-mentioned document, and this frame has a priority code PR (5) and a self address SA (6
), destination address DA (7), control code CC (8
), message length code B (9), and data DAT
A (10) etc. A pause period (11) of 10 m5 is set between each frame.

FIG. 6 is a timing chart showing the procedure for determining the number of collisions when a plurality of terminals start transmitting on the home bus (4) at the same time in the above-mentioned document. This is a case where the housekeeping controller (2) and the housekeeping controller (2) start transmitting at the same time.

When a plurality of frames conflict like this, each terminal verifies the transmitted data and received data bit by bit using the priority code PR (5) and its own address SA (6).

The home bus (4) is set so that logical 0 data has priority over logical 1 data.

Here, since the teleconverter (1) and the housekeeping controller (2) have the same priority code PR (5), they continue transmission based on the match between the transmitted data and the received data.

However, as shown in Figure 4 above, the teleconverter (
Since the address of 1) is 04H and the address of the housekeeping controller (2) is 02H, only the housekeeping controller (2) detects a mismatch between the sent data and received data due to a bit conflict in the self address SA (6). detected, immediately stops sending and starts receiving.

Then, the teleconverter (1) continues to transmit.

[Problems to be Solved by the Invention] However, in the conventional home control system configured as described above, the data sent and received exceeds the capacity of each terminal, making correct data transmission impossible. There was a problem with putting it away.

That is, since the home control terminal in the above system is a home appliance product, there is a limit to the cost spent on its hardware, and this burden often extends to memory, especially when a one-chip microcomputer is used.

As a result, if a terminal continues to receive data from a terminal with a higher transmission priority than itself, even if it has to make a transmission request to one of the terminals as a result of processing the received data, it will not be able to send its own data. Since the priority is low, transmission cannot be started on the transmission path, causing the reception buffer to overflow and the received data to be lost.

The present invention was made in view of the above-mentioned conventional problems, and its purpose is to reliably transmit and receive data without increasing hardware costs, and to minimize the complexity of communication control. Our goal is to provide a complete home control system.

[Means for Solving the Problems] In the communication method of the home control system according to the present invention, when the buffer memory capacity of a certain terminal overflows and data is received from a terminal with a higher transmission priority than the terminal, The configuration is such that a reception refusal frame is sent to the source of the data to stop the transmission, and when the reception buffer becomes empty, the transmission permission frame is sent to the source terminal.

[Operation] According to the present invention configured as described above, when a certain terminal transmits data to a terminal with a lower transmission priority than itself, and a reception rejection frame is returned in response to the transmission, Interrupts transmission of next data.

Then, the transmission data is retransmitted only after a reception permission frame is transmitted.

[Example] Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 3 is a block diagram of a conventional home control system, and the basic structure of the present invention is the same. In addition, the addresses of these terminals (1) to (3) and the format of the frame to be transmitted are also
This is the same as the conventional example shown in Figs.
3) is 06H.

Conflict effects when multiple terminals start transmitting at the same time are also performed as in the conventional example, as shown in Figure 6, and when the transmission frames of the teleconverter (1), housekeeping controller (2), and room controller (3) conflict. The priority set by the self address (telephone controller (1), housekeeping controller (2), room controller (3)
)) determines which one to adopt.

FIG. 7 shows the internal configuration of the housekeeping controller (2) in FIG. ) is connected to the microcomputer (12), and a memory (14) for temporarily storing data to be sent and received is connected to the microcomputer (12), and this memory (14) functions as a reception buffer.

The details of the method of the present invention will be explained below with reference to the sequence diagram shown in FIG. 1 showing the communication control procedure of the method of the present invention and the flowchart shown in FIG. 2 showing the operation of the housekeeping controller (2) operating according to the method of the invention. Explain the effect of

First, when the housekeeping controller (2) detects received data 1 (21) from the teleconverter (1), (31
), - After storing the received data 1 (21) in the memory (14) which is a reception buffer (S2), the memory (14)
Retrieve received data 1 (21) from and process it (S3)
.

As a result, the housekeeping controller (2) starts transmitting the generated transmission data (1) to the room controller (1) onto the home bus (4) (S4), but at this point, the teleconverter (1) also transmits the data at the same time. 4, the address of the teleconverter (1) is 04H and the address of the housekeeping controller (2) is 02H, so the teleconverter (1) with the higher transmission priority due to a bit conflict with its own address SA (6). ) will survive. Therefore, only the housekeeping controller (2) with a low transmission priority detects the collision (S5), immediately stops transmission, and then receives the received data 2 (22).

At this point, the reception buffer is empty (S6), so the reception data 2 (22) is stored in the memory (14) (S7), and transmission of the transmission data (1) is started again (S4).

However, if the teleconverter (1) starts transmitting at the same time again this time, the teleconverter (1) wins in the bit conflict of its own address SA (6) as before, and the housekeeping controller (2) detects a collision again (S5) and receives the However, if the reception buffer is for one frame, the previous reception data 2 (22) has already been stored and remains unprocessed.

Therefore, it is understood that the reception buffer is currently full (S6).

Therefore, a request to transmit a receiving frame is generated, and the transmission of this frame is started (S4).

If no terminals start transmission at the same time, no collision will occur (S5), so the transmission of this reception rejection frame (24) can be completed (S9).

Furthermore, since the transmission request for the transmission data 1 (25) remains (S10), transmission of this is started (S4).
.

Here, if the room controller (3) starts transmitting at the same time, from Fig. 4, the room controller (3)
The address of 2) is 02H1, and the address of the room controller (3) is 06H, and the housekeeping controller (2) survives the self-address conflict, so it does not detect a collision (S5) and transmits data 1 (25). transmission can be completed (S9).

As shown in Figure 5, there is a pause period of 10m5 between frames (
11), and in a system where the terminal can process the received data (S3) during this 10 mS period, when the receive buffer is full, a transmission request is always generated and transmission starts, so the receive buffer is There is no need for a terminal with a lower transmission priority to receive more data in a full state.

Therefore, in this case, the housekeeping controller (2
) in the program of the microcomputer (12), there is no need to control the transmission of a reception rejection frame to a terminal with a lower transmission priority than itself.

Next, since received data 2 (22) remains in the memory (14) <S 11), after taking it out and processing it (S3), transmitting data 2 (26) is transmitted (S4)
, (85), (S9), (SIO).

As a result of the above, the memory (14) becomes empty (S11), and as mentioned above, the reception rejection frame (
24) is currently being transmitted (S12), and in response, a transmission permission frame (27) is transmitted (S1
3), (s4), (S5), (S9).

Note that if the priority code PR(5) of the reception-rejected frame is set so that the transmission priority is higher than that of other frames,
If the transmitted data is not received because the buffer is full, a reception rejection frame is always returned immediately after the data transmission, which further improves the performance of the system.

[Effects of the Invention] As explained above, according to the method of the present invention, when receiving data from a terminal with a high self-imaging transmission priority when the buffer is full, a reception rejection is returned. If a reception rejection is not returned, it means that the transmitted data has definitely been received and processed, and it is possible to effectively avoid the inconvenience of the transmitted data overflowing from the buffer and disappearing as it is.

Additionally, when a reception rejection is returned, it is possible to take recovery measures such as waiting for transmission permission and retransmitting, which can improve communication reliability without increasing hardware costs such as increasing buffer capacity. .

Further, by omitting this control for terminals with lower transmission priority than the terminal itself, it is possible to minimize the complexity of the control program.

[Brief explanation of the drawing]

FIG. 1 is a sequence diagram showing the communication control procedure according to the present invention, FIG. 2 is a flowchart showing the operation of the housekeeping controller (2) operated according to the present invention, and FIG. 3 is a conventional home control according to the present invention. A system configuration diagram, FIG. 4 is an address table diagram showing addresses of conventional home control system terminals of the present invention,
Fig. 5 is a block diagram showing the format of transmission frames in the present invention and the conventional home control system, Fig. 6 is a timing diagram showing the procedure for detecting collisions of multiple frames, and Fig. 7 shows the internal structure of the housekeeping controller. FIG. In the figure, (4) is a home bus, (24) is a reception refusal frame, and (27) is a transmission permission frame. In addition, in the figures, the same reference numerals indicate the same or equivalent parts. Agent: Patent attorney Masuo Oiwa (2 others) Communication control procedure of the present invention system Fig. 1 1 Telephone controller 2: Housekeeping controller 3 Room controller 4: Home bus Home control system configuration Fig. 3 Transmission The 5th frame of the frame

Claims (1)

[Claims] A bus-type transmission path connects a plurality of terminals equipped with a buffer memory for temporarily storing received data, and sets transmission priorities for each terminal based on addresses, etc., and sets priorities in the event of a collision. In a home control system that performs communication control that detects collisions and interrupts transmission only in terminals with low levels of data transmission, when further data is sent to a terminal whose buffer memory has already reached its reception limit, the transmission is terminated. The present invention is characterized by transmitting a reception refusal frame to the data transmission source terminal, and transmitting a transmission permission frame to the transmission source terminal when the data processing in the terminal progresses and the buffer memory becomes ready for reception. communication method for home control systems.