JPS6155301B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an outdoor unit including a central control unit;
In a multi-system such as an air conditioner consisting of multiple indoor units each having a terminal control unit connected to the central control unit, the central control unit By simultaneously transmitting and receiving data from all terminals in synchronization with the clock pulses sent from the controller, the status of each terminal can be recognized at the same time, and controlled objects such as compressors and valves connected to the central control unit can be controlled. An object of the present invention is to provide a data transmission system that facilitates control suitable for the overall condition, and also facilitates noise contamination detection when using an inexpensive transmission line in which noise easily contaminates the transmission line.

Another object of the present invention is to provide a means for starting a block of blocked data using only a simple timer without using any special code.

A method of transmitting or receiving data in synchronization with a clock pulse is known as a so-called synchronous method. In this method, since transmission or reception is performed when a clock pulse is issued, if noise is mixed into the clock pulse, erroneous data will be transmitted or received. Therefore, in order to prevent malfunctions caused by this, various logic checks such as parity check and return verification must be performed for each block of received data. Especially for multi-type air conditioners, etc.
This is a particularly serious problem in systems where the transmission line is made of simple electric wires and also has a large noise source such as a compressor itself.

Additionally, to detect the start or end of one block of data, a common method is to send a certain code such as SOH (indicating the start of a block) or ETB (indicating the end of a transmission block) to indicate the start or end. However, this method requires a logical judgment as to whether or not the code corresponds to this, and has the disadvantage that the number of bits to be transmitted increases.

In this conventionally known method, a lot of processing and logical judgment is required for data transmission processing, so it is more difficult to control equipment than transmission control, such as air conditioners such as multi-air conditioners. If it is to be adopted in a system whose main purpose is to use the same method, the cost will increase and it cannot be adopted.

Hereinafter, the present invention will be described in detail using an example in which the present invention is applied to a home multi-air conditioner having one outdoor unit, three indoor units, and another control panel.

FIG. 1 is a diagram showing the configuration of the above system.

1 is a central control section installed in the outdoor unit;
In addition to the transmission lines shown in the diagram, the main purpose is to control the air conditioning of each indoor unit by controlling the compressor, blower, or valves that control the refrigerant flowing to each indoor unit depending on the status of each indoor unit. For this control, various data such as operating switches and room temperature are exchanged between each indoor unit. Reference numerals 2, 3, and 4 indicate indoor units connected to the outdoor units, each of which communicates data with the central control unit 1, and also includes devices installed in the indoor units 2, 3, and 4. For example, a terminal control unit for controlling a ventilation fan and various displays is provided.

Reference numeral 5 denotes a central control panel connected to the central control unit, which is provided with a terminal control unit that displays the operating status of each room and also communicates data with the central control unit 1. In addition to the illustrated transmission lines, there are connections necessary for the air conditioner, such as refrigerant piping, between each indoor unit 2, 3, 4 and the outdoor unit, but these will not be explained here.

Now, the transmission line constituting the transmission system according to the present invention consists of three lines, a transmission line, a reception line, and a data clock line, between the central control unit and one terminal. Of course, a common ground line is also required, but this is not included for simplicity.

Now, in FIG. 1, the transmission lines between the central control section 1 and the terminal control sections of one indoor unit 2 are, considering the central control section 1 as the center, the transmission line SL1 connected to the output end S1, This is connected to the input terminal of the terminal control unit, and from the perspective of the terminal control unit it becomes a receiving line, but to avoid confusion, from now on all lines are connected to the central control unit 1.
Look at it as the main subject.

Receiving line connected to input terminal R1 of central control unit 1
Three data clock lines RL1 and CKL connected to the output terminal S1 of the central control unit 1 are connected. In synchronization with the pulse of the output terminal CLK, data transmitted from the central control unit 1 is output from the output terminal S1 and read into the terminal control unit, and at the same time, data is output from the terminal control unit and input to the input terminal R1 of the central control unit 1. be done.

Similarly, the terminal control section of the indoor unit 3 and the central control section 1 are connected to another transmission line SL2 and reception line RL2, which are independent of the terminal control section 1, and in addition to this, a data clock common to the entire unit is connected. Line CKL is connected. Below, the terminal control sections and central control section 1 of other indoor units 4 and centralized control panel 5 are connected to independent transmission lines SL3, SL4 and reception lines, respectively.
RL3 and RL4 are connected, and CKL is connected to each as a common data clock line. A feature of the present invention is that a data clock line CKL common to all control sections is connected to the input terminal IRQ of the central control section 1, which is the source of the clock pulses. This allows the central control section 1 to check the pulse signal it has issued.

Now, in order to realize the data transmission system according to the present invention, a logic judgment section is required to create the transmission data and analyze the reception data, and at the same time, a timer and the like to measure the interruption time of the clock pulse are required. Furthermore, although not shown in the drawings, as mentioned above, considerable logical judgment and calculation functions are required to control various devices such as the compressor and the blower fan. Considering these points, it is preferable to use a so-called microcomputer for each control section. A microcomputer is a computer that inputs data, performs calculations, and outputs data according to predetermined control procedures.
It is an integrated circuit element that can be turned on and off, and also has a memory section that stores the control procedure described above.
A block diagram of a one-chip microcomputer integrated in one integrated circuit device is shown in FIG.
This is a microcomputer suitable for implementing the present invention, and the ROM is a storage unit that stores predetermined control procedures, so-called programs. The instruction analysis section analyzes the code stored in the ROM, the RAM is a temporary data storage section, X and Y are registers, ACC is a calculation register, ALU is a logic operation unit, and output through the output buffer. Ends S1, S2...
CLK, and there is also an input terminal connected to the input buffer. Further, IRQ is also an input terminal, and by this input, an interrupt can be caused during the execution of the program, and the corresponding processing can be performed. The OSC is an oscillator that generates the operating timing for the entire microcomputer, and the control section controls all of these. Also, the timer
It counts the oscillations from the OSC and sets the TF when it reaches a predetermined value, and by using this timer, it is possible to measure a predetermined time. Also, the shift register changes the data in the shift register in synchronization with the pulse that enters the input terminal CLKK.
It is output to SO and read into the shift register from input terminal SI. Further, the contents in this shift register can be taken into the calculation register ACC by an appropriate command and stored in the storage RAM, or can be subjected to logical judgments and calculations.

In addition, the shift counter sets SF when the pulse input to the input terminal CLKK reaches a predetermined value.
Indicates that the shift register is full of data.

When a microcomputer as described above is used as the central control unit 1 of the present invention, the transmission lines SL1, SL2...SL4 to each terminal control unit are connected to the output terminals S1, S2...S4 via appropriate buffers. Connect and receive lines RL1, RL2,... from each terminal control unit.
... are input terminals R1 and R through a suitable buffer.
2. Connect to... and clock data line
CKL is also connected to the output terminal via a suitable buffer.
It is best to connect it to CLK and also to the interrupt input terminal IRQ.

When used as a terminal control section, the transmission line SL from the central control section 1 becomes an input in the terminal control section, so it is connected to the input terminal SI of the shift register, and the reception line RL of the central control section 1 is connected to the input terminal SI of the shift register. Since it is the output of the terminal control section, connect it to the output terminal SO of the shift register. It is very convenient to connect the data clock line CKL to CLKK, which is the shift clock input terminal of the shift register.
In other words, data is output from the shift register in synchronization with the pulse of the data clock line CKL, and is read from the input terminal SI at the same time. When the shift register is full, SF becomes 1, so the data in the shift register is read at this time. All you have to do is make a logical judgment and set new transmission data in the shift register.

Now, FIG. 3 shows a time sequence in the central control unit for data transmission according to the present invention. Third
The figure only shows the interaction with the terminal control section of the indoor unit 1. S1 is the signal of transmission line SL1, R
1 indicates a signal on the receiving line RL1, CLK indicates a signal on the data clock line CKL, and IRQ indicates an input signal to which the data clock line CKL is also connected.

The central control unit 1 first sends the transmission data to the output terminal S1.
When the output terminal CLK is set to 1, the data is read into the terminal control section of the indoor unit 1 and simultaneously sent to the reception line RL1. After setting the clock pulse to φ, read this received data,
Thereafter, this process is repeated at a substantially constant period t _a .
When a predetermined number of data transmissions are completed, one block is completed and the clock pulse is kept at φ for a starting time t _b before starting transmission of the next one block. In this way, the period t _a and the start time t _b can be easily measured by using the built-in timer. After the start time t _b has elapsed, the transfer of the next block begins in the same way, setting data and sending clock pulses.
Read data. A feature of the present invention is that the state of the input terminal IRQ is constantly monitored during these operations. In other words, in the part other than point A in the diagram, the output terminal CLK that you output and the data block line
The data clock line CKL changes at exactly the same timing as the input terminal IRQ that reads CKL.
A logical judgment is made that there is no noise mixed in.
However, at point A in the diagram, its own output terminal
Although the CLK signal remains φ, the signal at its input terminal IRQ has become 1. This logically determines that some kind of noise has entered the data clock line CKL, immediately terminates data transmission, and suspends the clock pulse at the start time _tb for transmitting the next new block.

FIG. 4 and FIG. 5 show the above-mentioned central control unit 1.
3 is a flowchart showing a control sequence of FIG.
In FIG. 4, after setting the initial values of the microcomputer and setting the output from the starting point, a start time t _b is set in the built-in timer and the timer is operated (a). Thereafter, processing other than transmission, such as controlling the compressor, is performed until time t _b elapses at C (b). Then, at C, when time t _b has elapsed, at d the counter for counting the number of data in one block to be transmitted is reset, at e the first data is set in S1, and at f the clock pulse is set to 1. Then, at g, set t _a in the timer and operate the timer, and at i, read the received data of R1, add 1 to the counter for the number of transmitted data, and (j) check from that number whether one block is completed or not at k. is determined, and in the case of completion, returns to a. If it has not been completed, wait at l for the time t _a and then go to e to repeat the transmission of the next data.

During this series of operations, if the interrupt operation is made to occur when the input terminal IRQ becomes 1, the input terminal
Each time the IRQ becomes 1, the control procedure shown in the flowchart of FIG. 5 is executed. That is, whether or not the signal at the output terminal CLK was set to 1 at this point in time at m (that is, whether it was the moment when f in Figure 4 was executed).
If so, it is normal operation of n and returns from the interrupt. However, it is the output end
If this occurs even though CLK has not been set to 1, it is determined that the output terminal CLK has become 1 due to noise, the abnormality (o) process is performed, and the process returns to a in Figure 4. Just go into transmission.

Correspondingly, in the terminal control section, following the flowchart showing the processing procedure shown in FIG. 6, after performing necessary initialization processing such as resetting the output from the starting point, ,1
After resetting the data counter for counting the number of data in the block, setting the data to be sent to the shift register in step B, and setting the reset time _tc in the internal timer in step C, processing other than transmission is performed in step D. For example, a blower fan is controlled, and in E, it is determined by SF whether the shift register is full. If it is full, read the data in F and store it in a suitable storage section, add 1 to the data counter in T, return to B to set the next data, and set t to the timer again in C.
Set _c .

If the shift register is not full in E, it is determined whether the time t _c has elapsed or not, and if it has not elapsed, the process returns to D. However, t _c
If time has elapsed, it means that t _c time has passed since the data was received previously, then t _a <
If the relationship is set such that t _c < t _b , the central control unit determines that it has entered the waiting time for the start time of t _b , determines that one block has been completed, and goes to the next step. Here, the data counter is Check the value, and if it is equal to the value for one block, it is determined that one block of data has been successfully communicated, and after processing that data in N, it returns to Step 1 in preparation for communication of one new block. Return.

However, if the number of data does not match the number of data for one block, it is determined that the interruption is due to noise like the one that occurred at A in FIG.
It returns to step 1 without processing the data and prepares for the start of the next block.

In this way, the terminal control section can detect the start and end of one block simply by monitoring the reset time tc, which is very simple. Since the quality of one block of data can be judged by simply counting the number of data in one block, an extremely simple logical judgment configuration can be achieved, and the processing required for transmission in the terminal control section is reduced. Furthermore, the reliability of data transmission is improved because noise contamination is detected in the central control unit as well.

Furthermore, since data can be exchanged simultaneously with all terminal control units using one data clock line, control can be performed that best suits the conditions of all terminals. In other words, in systems such as multi-air conditioners where multiple indoor units are connected to one compressor, the compressor must be controlled taking into account the status of all indoor units at that time. . Therefore, in a transmission system where the status of each indoor unit can only be recognized sequentially,
Since control cannot be performed until data from all indoor units can be collected, the control of the compressor and other equipment may be delayed, causing inconvenience.

The effects of the present invention are listed below.

(1) The central control unit and each terminal control unit only need to be connected by three transmission lines.

(2) The reliability of data is improved because noise contamination is determined.

(3) Since the relationship t _a < t _c < t _d is established, 1
The start of data in a block can be easily detected.

(4) Since the central control unit can receive the status of each terminal at the same time, this is extremely convenient in cases where control is adapted to the status of the entire terminal, such as in a multi-air conditioning system.

[Brief explanation of the drawing]

FIG. 1 is a system configuration diagram of a transmission section when a data transmission system according to an embodiment of the present invention is adopted in a multi-air conditioner, and FIG. 2 is a configuration diagram showing an example of a microcomputer suitable for implementing the present invention. FIG. 3 is a time chart of transmission data in the central control unit according to an embodiment of the present invention;
5 and 5 are flowcharts showing an example of the control procedure in the central control unit according to an embodiment of the present invention, and FIG. 6 is a flowchart showing an example of the control procedure in the terminal control unit according to the embodiment of the present invention. It is a chart diagram. 1... central control section provided in the outdoor unit,
2, 3, 4...indoor unit including a terminal control unit,
5... Centralized control panel including terminal control unit, CKL...
Data clock line, IRQ...Input terminal of central control unit.

Claims (1)

[Claims] 1. In a data transmission system consisting of a central control unit and a plurality of terminal control units connected to the central control unit, each terminal control unit and the central control unit are coupled through independent transmission lines and reception lines, and further, A data clock line is provided for transmitting a clock pulse indicating the validity of data on the transmitting/receiving line, and the data clock line is commonly coupled to an output terminal of the central control unit and an input terminal of each terminal control unit. and is also connected to an input terminal of the central control section, and each of the terminal control sections operates the transmission line/reception terminal in synchronization with a clock pulse sent from the central control section via the data clock line. A transmitter/receiver section that sends and receives data on the line, a data number counter that counts the number of clock pulses, and a data counter that detects that the clock pulse is interrupted for a predetermined reset time (t _c ) and controls the transmission of one block of data. a block end detection section that determines the end; and when the block end detection section detects the end of transmission of one block, the data number counter;
an error detection section that determines whether or not the number of data in one block is equal to a predetermined number of data; Then, the transmission of the clock pulse is interrupted for a predetermined start time t _b , and thereafter, the clock pulse is transmitted at a substantially constant period t _a , and between the t _a , t _b , and t _c , t _a < A data sending unit performs control to maintain the relationship t _c < t _b , and the data clock is determined by comparing the clock pulses input to the input terminal of the central control unit and the clock pulses output by the central control unit itself. A noise detecting section detects that noise has entered the clock pulse line, and when the noise detecting section detects noise, it stops sending out the clock pulse and restarts the clock pulse line.
A data transmission system comprising: an error detection section for instructing said data transmission section to restart the data transmission of a block from the beginning including interruption of clock pulse transmission for an interval of time.