JPH0342757B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a multiplex transmission system.

[Background technology]

Figure 1 shows a schematic configuration diagram of a multiplex transmission system, in which 1 is a base unit, 2 is a terminal unit, 3 is a signal line, and 4 is a terminal unit.
is a controlled load connected to the terminal device 2.
In this system, address data is sent from base unit 1.
AD, control data CD, and a transmission signal consisting of a long pulse RP that determines the return waiting period is transmitted sequentially for each address via the cyclic signal line 3,
The terminal device 2 reads the address data AD in the transmission signal, and when it matches its own address set in advance, takes in the control data CD and controls the load 4 based on the control data CD. Then, if necessary, the operation monitoring data of the load 4 is sent back as a return signal during the reception period of the long pulse RP.

FIG. 2 shows the format of the transmitted signal.

FIG. 3 shows a conventional terminal device 2. Reference numeral 5 denotes an address setting section consisting of a dip switch. What is the received address data AD?Address data comparison unit 7
When the address data AD and the set address match, the output switching circuit 8 is controlled to generate a control output based on the control data CD read by the signal receiving section 6. It's getting old.

By the way, in the multiplex transmission system that has actually been constructed and installed, if it is necessary to change the system, it becomes necessary to change the address of the terminal device.
Now, use the deep switch to set the address setting section 5.
, it is necessary to change the state of the deep switch each time, and if the terminal device 2 is installed in a place that is out of reach, it is difficult to change the address.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a multiplex transmission system in which the address can be changed arbitrarily by a signal from the base unit and the system can be easily changed.

[Disclosure of the invention]

FIG. 4 shows the format of the transmission signal used in the present invention. In contrast to the conventional transmission signal shown in FIG. 2, mode data MD is transmitted before address data AD. A control mode and an address mode are set, and in the control mode, the data that literally controls the load 4 is transmitted from the base unit 1 to the control data CD as in the past, and in the address setting mode, the data that literally controls the load 4 is transmitted from the terminal 1 during the transmission period of the control data CD. Address setting data for the device 2 is transmitted from the base device 1.

FIG. 5 shows an example circuit of the terminal device 2,
Reference numeral 9 in the figure indicates a mode judgment change section, and this mode judgment change section 9 transfers the above-mentioned mode data MD to the signal receiving section 6.
This is to determine whether the mode data MD is the control mode or the address setting mode.In the address setting mode, the address setting data is input from the signal receiving section 6 to the address latch 10 side. The output switching circuit 8 is configured to switch and set. Reference numeral 11 denotes an input data comparison section, and this input data comparison section 11 compares the unique address of the terminal set by the deep switch section 12 at the time of setting with the unique address data sent from the base device 1 in the address setting mode. Something,
When there is a match, the address latch 10 generates a signal to latch the address setting data mentioned above. Reference numeral 13 denotes an address data comparison section, which compares the address setting data latched by the address latch 10 and the address data AD in the control mode, and outputs control data CD when they match to the switching circuit 8.
This is for switching and setting the output switching circuit 8 so that the output is output as a control output.

The base unit 1 then cyclically transmits transmission signals consisting of mode data MD, address data AD, control data CD (address setting data), and long pulse RP to each address in sequence. Here, if the mode data MD is the address setting mode data, the base unit 1 sends the unique address data of the terminal unit 2 whose address you want to change to the address data AD.
At the same time, the data of the address to be set is transmitted as address setting data during the transmission period of the control data CD. In the terminal device 2, the signal receiving section 6 receives the transmission signal via the signal line 3,
A mode determination change section 9 performs mode determination. If the sent mode data MD is the address setting mode, the address data comparison section 13 is enabled, the input data comparison section 11 is enabled, and the output switching circuit 8 is switched to the address latch 10 side. Next, the address data AD after the mode data MD is taken in from the signal receiving section 6, and the input data comparison section 11 compares it with the unique address set in the deep switch section 12. If they match, the address setting data following the address data AD is taken in. is input to the address latch 10 via the output switching circuit 8 and latched. The latched address setting data becomes the calling address in the control mode thereafter.

Now, mode data MD of control mode from base unit 1
When transmitting , the next address data AD becomes the calling address data, and further address data
The next data after AD is control data CD. now,
When the control mode data is determined by the mode determination change unit 9, the mode determination change unit 9 enables the address data comparison unit 13 and disables the input data comparison unit 11. Next, the address data AD is inputted to the address data comparing section 13 via the signal receiving section 6, and the input data is compared with the latch data of the address latch 10. If the comparison results in a match, the output switching circuit 8 is switched to generate a control output for controlling an external device based on the next control data CD.

〔Effect of the invention〕

Since the present invention is configured as described above, the address of the terminal device to be called during control can be changed by the transmission signal from the base device side, and therefore the address of the terminal device can be changed one by one when changing the system. Since there is no need to change the address on the terminal side, the installation location of the terminal does not interfere with changing the address, so there is no need to specially select the address of the terminal depending on the installation location, which helps simplify the installation. play.

Moreover, each terminal device has a unique address in addition to the address setting data, and when changing the address setting data set in the address latch,
Since the terminal device is identified by determining whether the address data of the transmission signal and the unique address match, even if the address setting data is set incorrectly, the terminal device can be identified by the unique address. This has the advantage that address setting data can be easily modified. In other words, if a unique address is not provided and all terminals are set with the same address setting data, the problem may arise that the terminal cannot be identified and the address setting data cannot be modified. However, in the present invention, such a problem does not occur because a unique address is provided that takes precedence over address setting data.

[Brief explanation of drawings]

Figure 1 is a schematic diagram of the multiplex transmission system;
The figure is an explanatory diagram of the format of a conventional transmission signal.
The figure is a circuit block diagram of a conventional terminal device, FIG. 4 is an explanatory diagram of a transmission signal format of the present invention, and FIG. 5 is a circuit block diagram of a terminal device according to an embodiment of the present invention. 1 is a base unit; 2 is a terminal device, 3 is a signal line, 4 is a load, 6 is a signal receiving section, 8 is an output switching circuit, 9 is a mode judgment change section, 10 is an address latch, 11 is an input data comparison section, 12 is a deep switch section,
13 is an address data comparison section, AD is address data, CD is control data, and MD is mode data.

Claims (1)

[Claims] 1 Transmission signals consisting of address data, control data, etc. are transmitted from the base device via signal lines by time division multiplexing, and the terminal device whose set address matches the received address data takes in the control data and performs control operations. In a multiplex transmission system that performs multiplex transmission, the base device sends mode data for either control mode or address setting mode as a transmission signal together with address data, control data, etc., and the terminal device determines whether the received mode data is the control mode or the address. a mode determination change unit that determines whether it is in the setting mode; an address setting unit that sets an address specific to the terminal device; and an input data comparison that compares the address data and the set address when the mode determination change unit determines that it is in the address setting mode. and an address latch that latches the data of the control data transmission period as address setting data if the comparisons of the input data comparison section and the input data comparison section match, and an address latch that latches the data of the control data transmission period as address setting data if the comparison of the input data comparison section and the input data comparison section match; An address data comparison section that compares the address setting data latched by a latch, and if the address data comparison section matches, a control output based on the control data is generated. transmission system.