JPH04223633A - Address setting system for 1:n serial communication system - Google Patents

Abstract

PURPOSE:To unnecessitate providing a dip switch or the like for setting an address at every slave device, to prevent the erroneous setting of an address, and to improve a fail safe for preventing a system down. CONSTITUTION:A switch circuit 40 which opens and closes a communication line 30 between each slave device 20 is provided between each slave device 20. A master device 10 transmits an address setting signal peculiar to each slave device to each slave device 20 through the communication line 30 at the time of turning-on a power source, and each slave device 20 receives the address setting signal from the master device 10, and completes the address setting. Then, the switch circuit 40 between the slave device 20 and the next serially connected slave device 20 is closed, so that the next address setting signal from the master device 10 can get to the next slave device 20. The switch circuit 40 is constituted of plural switch elements connected in parallel and/or serially for safety.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to an address setting system in a one-to-N serial communication system, and more particularly, the present invention relates to an address setting system in a one-to-N serial communication system, and in particular, in which one base unit and a plurality of slave units are connected in series to the base unit through communication lines. The present invention relates to an address setting system in a 1-to-N serial communication system.

0002

2. Description of the Related Art A 1-to-N serial communication system is already known in which a base unit and a plurality of slave units are connected in series to each other via communication lines, and communication is performed between the base unit and each slave unit. This communication system is used in vending machines for various products,
In automatic ticket vending machines and other station equipment, multiple push-button switch units operated by users for selecting products, setting ticket purchase prices, etc. are used as child units, and one calculation control unit is used as a parent unit. It is being considered that this method can be used for communication between a plurality of push button switch sections and one arithmetic control section.

In automatic vending machines, automatic ticket vending machines, etc. using a 1-to-N serial communication system, it is no longer necessary to connect each of the plurality of push button switch sections to one arithmetic control section through individual signal lines. The number of wires can be reduced, and it is also possible to easily accommodate an increase in the number of push button switch sections.

0004

[Problems to be Solved by the Invention] However, in a 1-to-N serial communication system, each slave unit, such as a push button switch unit, is required to have an individual Address needs to be set.

[0005] This address setting is generally performed by a hardware configuration using a dip switch, etc. provided for each slave device, but in this case, it is necessary to provide a dip switch, etc. for each slave device. There is, which is
This may increase the cost of the device and may cause setting errors such as duplicate settings of the same address or forgetting settings.

The present invention has been made in view of the above-mentioned problems, and there is no need to provide a dip switch for setting an address for each handset, and there is no need to make an address setting error. A 1:N system that is fail-safe, less likely to cause system downtime, and has excellent operational reliability.
The purpose is to provide an address setting system in a serial communication system.

[0007]

[Means for Solving the Problems] According to the present invention, one base unit and a plurality of slave units are connected in series to each other by a communication line, and the base unit and each slave unit are connected in series to each other by a communication line. In the address setting system in a 1-to-N serial communication system where communication is performed between etc., an address setting signal unique to each slave unit is sent to each slave unit via the communication line, and each slave unit receives the address setting signal from the base unit and completes the address setting. The switch circuit between the slave unit is closed, and when the switch circuit is closed, the next address setting signal from the base unit reaches the next slave unit, and the switch circuits are arranged in parallel with each other, and Alternatively, this can be accomplished by an address setting system in a 1-to-N serial communication system, which is characterized by comprising a plurality of switch elements connected in series.

[0008]

[Operation] According to the above-described configuration, when the power is turned on, each slave unit receives an address setting signal from the base unit and completes the address setting, so that the connection between the slave unit and the next slave unit connected in series is The switch circuit is closed, allowing the next address setting signal from the master unit to reach the next slave unit.
Address settings are automatically performed sequentially starting with the child device closest to the parent device.

[0009] The switch circuits are arranged in parallel with each other and/or
Since it is composed of multiple switch elements connected in series with each other, even if one of the switch elements becomes inoperable due to a disconnection, at least one other switch element connected in parallel will be disabled. If the switch element is operable, its closing operation will ensure a valid operating state of the switch circuit, and even if one of the switch elements becomes inoperable in the closed state due to a failure of the control gate, etc. If at least one other switch element connected in series with the switch element is operable, its opening operation ensures an effective operating state of the switch circuit.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows one embodiment of a 1-to-N serial communication system implementing an address setting system according to the present invention. The 1-to-N serial communication system includes one base unit 10,
The base unit 10 and the multiple slave units 20 are connected in series with each other by a communication line 30, and the communication line 30 connects the base unit 10 and each slave unit 20. Communication is now taking place between them.

As shown in FIG. 2, the base unit 10 has a C
PU 11, system program memory 12, handset reception register 13, handset transmission register 14, serial-parallel converter 15 for reception, parallel-to-serial converter 16 for transmission, input terminal CIN, output terminal COUT and an input terminal C
Both IN and output terminal COUT are connected to a communication line 30.

The system program memory 12 stores a system program for overall control and an address setting program.
It is called by the CPU 11 and executed by the CPU 11 when the power is turned on, reset, etc., and an address setting signal unique to each slave unit is transmitted to each slave unit 20 via the communication line 30. In addition, in this embodiment, CPU1
When a power-on signal is applied to 1, an address setting program is executed.

As shown in FIG. 3, each slave unit 20 has a receiving serial-to-parallel converter 21, an address setting register 22 for setting its own address, and an address set in the address setting register 22. An address comparator 23 that compares communication data with an address, a latch circuit 24 having a latch area for received data and a latch area for transmitted data, a parallel-to-serial converter 25 for transmission, and a latch circuit 24
A three-state output circuit 26 receives transmission data via a parallel-to-serial converter 25 and changes its output state in response to a control signal from an address comparator 23, and a plurality of manual switches 2 such as push button switches.
7, a light emitting element 28 that displays a message such as "on sale", and "
Light-emitting element 29 that displays messages such as “Sold out” and “Sold out”
, an input terminal IN, and an output terminal OUT, and both the input terminal IN and the output terminal OUT are connected to the communication line 30 . The address setting register 22 is a volatile address memory, and after being given a power-on signal, the address setting register 22 is a volatile address memory.
The address setting signal from 0 is taken in only once and held.

A switch circuit 40 is provided between adjacent slave units 20 to open and close the communication line 30 between the two slave units 20. The switch circuits 40 between each handset 20 are each
As shown in FIG. 4, a plurality of (n×n) analog switch elements 4211 to 42nn are connected in parallel and in series between the connection terminal a and the terminal b.
Analog switch elements 4211 to 42
Each control gate Ga, Gb of nn is connected to a common control signal terminal c, from which a control signal can be applied all at once.

An on signal is given to the control signal terminal c due to an address being set in the address setting register 22 of the corresponding slave device 20, and an on signal is given to the control signal terminal c. If so, the analog switch elements 4211 to 42nn will be closed all at once in one switch circuit unit by applying an ON signal or an inverted signal thereof to each control gate Ga and Gb at the same time. There is.

The input terminal IN of each slave unit 20 is connected to the communication line 30 on the side of the base unit 10 from the switch circuit 40 between the next slave unit 20 in the series connection, and the output terminal OUT of each slave unit 20
is connected to the communication line 30 on the side of the next slave unit 20 from the switch circuit 40 between it and the next slave unit 20 connected in series.

It should be noted that the switch circuit 40 attached to the final, ie, Nth, slave unit 20 is not necessarily required, and is provided for uniformity of each slave unit as a component.

Next, the address setting operation of the handset 20 will be explained using FIG.

In this embodiment, the address setting of the slave device 20 is executed when a power-on signal is given to the CPU 11, that is, when the power is turned on, and in this address setting, initialization is first performed. I (Step 10)
As a result, an off signal is output to the control signal terminal c of each switch circuit 40, all of the analog switch elements 4211 to 42nn of each switch circuit 40 are turned off, and the three-state output circuit 26 of each slave unit 20 outputs an off signal. The terminal OUT is set to a non-logic state due to high impedance. Also, in this initialization, the count n is reset to "0".

When all of the analog switch elements 4211 to 42nn of the switch circuit 40 are turned off, one of the analog switch elements 4211 to 42nn becomes closed and inoperable due to a failure of the control gates Ga, Gb, etc. also, if at least one other analog switch element connected in series with this is operable,
This opening operation ensures an effective operating state of the switch circuit 40. That is, a row of analog switch elements connected in series, for example, analog switch elements 4211 to
As long as all of the switch circuits 421n are not closed and become inoperable at the same time, the effective operating state of the switch circuit 40 is ensured.

Next, the CPU 11 of the base unit 10 sets the address setting signal ADD to "address 0" (step 20).
), this address setting signal ADD is sent to the handset transmission register 1.
4. Send the output terminal COUT to the communication line 30 via the parallel-to-serial converter 16 (step 30).

At this time, all of the switch circuits 40 are still in the off state, so the address setting signal ADD of address 0 is applied to the input terminal IN of the first slave unit (slave unit 0) 20.
, only the first handset 20 receives the address setting signal ADD of "address 0", this is taken into the address setting register 22 of the first handset 20, and the address setting register 22 holds it. I come to do it. As a result, the address of the first handset 20 is “0”.
” is set.

When the address setting of the first handset 20 is completed, the first handset 20 sets its own output terminal OUT to the output state, and the next second handset (handset 1) 2
0, an on signal is output to the control signal terminal c of the switch circuit (SW0) 40, and this switch circuit 4
0 analog switch elements 4211 to 42nn are all turned on. As a result, all of the analog switch elements 4211 to 42nn of one switch circuit 40 are turned on.

When all of the analog switch elements 4211 to 42nn of one switch circuit 40 are turned on, the analog switch elements 4211 to 42n are turned on due to disconnection or the like.
Even if one of n is in an open state and becomes inoperable, if at least one other switch element connected in parallel with it is operable, the switching circuit 40 can be operated effectively by its closing operation. The effective operating state of the switch circuit 40 is ensured, that is, unless all of the analog switch elements in each column connected in parallel, for example, the analog switch elements 4211 to 42n1, become inoperable due to the open state at the same time. Secured.

The CPU 11 starts time counting by the timer T from the time when the address setting signal ADD is sent to the communication line 30 (step 40), and from the time when the address setting signal ADD is sent to the communication line 30, a predetermined time TSET is started.
elapses (step 50), the timer T is reset and the count n is incremented by one (step 60).
).

[0027] At this time, the switch circuit 40 between the first handset 20 and the next second handset 20 is turned on.

Next, it is determined whether the count n has reached N, which is one smaller than the number of slave units 20 (step 7).
0), if n=N, the address setting operation ends as the address setting of all the handsets 20 is completed, whereas if n=N, the address setting of all the handsets 20 is still completed. If not, the address number of the address setting signal ADD is incremented by one in order to set the address of the next handset 20 (step 80), and the process returns to step 30 and this new address setting signal ADD, this Sometimes, the address setting signal ADD of "address 1" is sent to the communication line 30 from the output terminal COUT of the base unit 10.

[0029] At this time, the first slave unit 20 (slave unit 0)
Since the switch (SW0) 40 between this and the next second handset (slave unit 1) 20 is in the on state, the main unit 1
0's output terminal COUT to the communication line 30.
The address setting signal ADD for “Address 1” is set by the switch (S
W0 ) 40 and the input terminal I of the second slave unit 20
N, the second handset 20 receives the address setting signal ADD of "address 1", this is taken into the address setting register 22 of the second handset 20, and the address setting register 22 holds it. I come to do it. As a result, the address of the second handset 20 is "1"
is set to

When the address setting of the second handset 20 is completed, the second handset 20 sets its own output terminal OUT to the output state, and also switches between the second handset 20 and the third handset (handset 2) 20. All analog switch elements 4211 to 42n1 of the circuit (SW1) 40 are turned on. As a result, this switch circuit 40 is turned on.

Thereafter, the CPU 11 of the base unit 10 repeats the address setting as described above, so that the addresses of the slave units 20 are automatically set in the order of those closest to the base unit 10.

[0032] When the address setting of all slave units 20 is completed, the address setting operation is completed, and from then on, communication is performed between the master station 10 and each slave unit 20 according to the set address, and the manual Signals related to the opening and closing of the switch 26 are transmitted from each slave unit 20 to the base unit 10, and the base unit 10
starts transmitting light emission control signals for the light emitting elements 27 and 28 of each slave unit 20 to each slave unit 20 (step 90).

[0033]

As can be understood from the above explanation, according to the address setting system in a 1-to-N serial communication system according to the present invention, each slave unit receives an address setting signal from the base unit when the power is turned on, etc. By receiving this and completing the address setting, the switch circuit between the next slave unit in the series connection is closed, so that the next address setting signal from the base unit can reach the next slave unit. Since address settings are automatically performed sequentially starting from the child device closest to the parent device, there is no need to provide a dip switch for address setting on each child device, and there is no possibility of setting errors, reducing costs. At the same time, maintainability is greatly improved.

[0034] The switch circuits are arranged in parallel with each other, and/or
Since it is composed of multiple switch elements connected in series with each other, even if one of the switch elements becomes inoperable due to a disconnection, at least one other switch element connected in parallel will be disabled. If the switch element is operable, its closing operation will ensure a valid operating state of the switch circuit, and even if one of the switch elements becomes inoperable in the closed state due to a failure of the control gate, etc. If at least one other switch element connected in series with the switch element is operable, its opening operation ensures a valid operating state of the switch circuit, thereby providing fail-safe protection and preventing system failure due to a fault in the switch circuit. Failures are less likely to occur and operational reliability is improved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of a 1-to-N serial communication system implementing an address setting system according to the present invention.

FIG. 2 is a block diagram showing an example of the configuration of a base unit used in a 1-to-N serial communication system that implements the address setting system according to the present invention.

FIG. 3 is a block diagram showing a configuration example of a slave device used in a 1-to-N serial communication system implementing the address setting system according to the present invention.

FIG. 4 is a circuit diagram showing a configuration example of a switch circuit used in a 1-to-N serial communication system implementing the address setting system according to the present invention.

FIG. 5 is a flowchart showing the address setting operation in the address setting system according to the present invention.

[Explanation of symbols]

10 Base unit 20 Child machine 30 Communication line 40 Switch circuit

Claims (2)

[Claims] Claim 1: In a 1-to-N serial communication system, in which one base unit and a plurality of slave units are connected in series to each other via a communication line, and communication is performed between the base unit and each of the slave units. In the address setting system, a switch circuit is provided between each slave unit to open and close the communication line between each slave unit, and when the power is turned on, the base unit uses the communication line to send a unique message to each slave unit. The address setting signal is transmitted, and each slave unit receives the address setting signal from the base unit and completes the address setting, thereby closing the switch circuit between the next slave unit in the series connection, and the switch circuit is closed. When closed, the next address setting signal from the master device reaches the next slave device, and the switch circuit is composed of a plurality of switch elements connected in parallel to each other. An address setting system in a 1-to-N serial communication system. 2. In a 1-to-N serial communication system in which one base unit and a plurality of slave units are connected in series to each other via a communication line, and communication is performed between the base unit and each of the slave units. In the address setting system, a switch circuit is provided between each slave unit to open and close the communication line between each slave unit, and when the power is turned on, the base unit uses the communication line to send a unique message to each slave unit. The address setting signal is transmitted, and each slave unit receives the address setting signal from the base unit and completes the address setting, thereby closing the switch circuit between the next slave unit in the series connection, and the switch circuit is closed. When closed, the next address setting signal from the master device reaches the next slave device, and the switch circuit is composed of a plurality of switch elements connected in series with each other. An address setting system in a 1-to-N serial communication system.