JP3494542B2 - Wireless data communication system and duplexing method thereof - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless POS (Positive
int Of Sales: Point-of-sale information management) wireless system
The present invention relates to a data communication system and a duplex method thereof. [0002] Generally, a wireless POS system is a computer.
When a wireless base station is connected to a host device such as
Both are a plurality of POS terminals controlled by the host device.
Finally, a wireless slave station capable of wireless communication with the wireless base station
The data communication between the host device and each POS terminal
The communication is performed wirelessly. For example, there is
When a customer purchase product is registered for sale at the POS terminal,
Inquiry message for product data from the POS terminal's wireless slave station
Transmitted wirelessly. Then, this message is sent to the radio base station.
And input to the host device by wire communication. This
As a result, the higher-level device sends the product price, product name,
Product data is given to the wireless base station, and the POS terminal
It is transmitted wirelessly at the end. This product data is received by the wireless slave station
The POS terminal, the product sales based on the product data
Sales registration processing of sales data is performed. By the way, such a wireless POS system has been proposed.
System, a failure occurs in a higher-level device, or
When communication between the POS terminal and the POS terminal becomes abnormal, the POS terminal
Registration with the product in error and accounting with the shopper
Host device and wireless base station
Is being duplicated. [0004] Specifically, a higher-level device is referred to as a first higher-level device.
A pair of second higher-level devices, and each higher-level device
Connect each base station with a wired connection, and
A line switch is interposed on the line. And each upper device,
Monitor each other's operation and detect abnormalities in the other host device.
Knowingly, each wireless base station connected to the other higher-level device
Controls the line switch so that is connected to itself. like this
By doing so, under the control of the host
POS terminal can perform data communication with a normal host device
It does not hinder business. [0005] Also, each radio base station has its own substitute.
The radio base station is determined in advance. And each higher-level device
Monitors the status of each wirelessly connected wireless base station, and
When an abnormality of the radio base station is detected, the
The substitute radio base station substitutes the function of the radio base station.
By doing this, the wireless base station that has become abnormal
The connected POS terminal is updated via the alternative radio base station.
Since data communication with other devices is continued,
There is no hindrance. [0006] However, the above-mentioned problems
Conventional wireless type with dual host device and wireless base station
In data communication systems, higher-level devices and wireless base stations
If the line connecting the
A wireless base station and an alternative wireless base station are connected
If the wireless base station and the alternative wireless base station
The problem that all POS terminals connected by line becomes unusable
There was a title. [0007] Therefore, the present invention provides a method for controlling higher-level equipment and wireless base stations.
Not only failures, but also failures to connect higher-level equipment to wireless base stations.
Even if the line breaks, each controlled terminal and the host
Wireless data communication system that can secure
It is intended to be offered. [0008] The invention according to claim 1 of the present application.
Means that at least two higher-level devices
Connect the base station by wire and
Wireless communication with each wireless base station to multiple controlled terminals to be controlled
Wireless stations that can perform
Data communication with your terminal is now done wirelessly
In wireless data communication systems, each higher-level device
Monitor itself and detect an abnormality in the other host device,
A means for substituting the function of the other higher-level device is provided. Ma
Also, a wireless base station wired to at least one higher-level device
The communication between the base station and the higher-level device by wire becomes abnormal.
Stops the wireless communication operation with the wireless slave station connected wirelessly.
Means for disabling wireless communication are provided. In addition, each controlled
The terminal has one main radio that performs radio communication with its own radio slave station.
The information about the base station and the wireless communication with the main wireless base station have failed.
At least one sub-radio group to switch to when it becomes available
Means for storing information about the local station,
When the wireless communication of the
Means for switching from a station to the auxiliary radio base station.
The main radio base station and the sub radio base station are different
Wireless base station wired to the host device. [0009] In addition, a wired connection between a host device and a wireless base station.
A means for detecting a communication abnormality is provided in the wireless base station. Soshi
When an error occurs in the host device, the
Of the wired communication between the wireless base station and the host device.
Before the means for detecting normal operation is activated, the other
Priority is given to means for detecting the
It is intended to work. An embodiment of the present invention will be described below with reference to the drawings.
This will be described with reference to FIG. First, the server and the radio base station
Wireless POS system with a bus-type wired line connecting
FIG. 1 illustrates a first embodiment in which the present invention is applied to a system.
This will be described with reference to FIGS. FIG. 1 shows a wireless P in the first embodiment.
It is an overall view of the OS system, including the unit price of each product, product name, etc.
Product data file storing product data and each POS end
Sales that aggregate sales data for each product registered for sale at the end
A first server as a higher-level device having an aggregation file and the like
S1 and a second server S2 are provided. And
The first server S1 is connected to a bus type via a line switch CH.
The first radio base station BSU1-1 and the second
A second server S connects two radio base stations BSU1-2.
2 to a bus-type communication path L2 via the same line switch CH.
The third wireless base station BSU2-1 and the fourth wireless base station B
SU2-2 is connected. Under the control of the servers S1 and S2,
Product sales data is used as a controlled terminal that performs sales registration processing.
And 20 POS terminals TM1-1-10 and TM2-1-10
Have. And each POS terminal TM1-1 to TM10, TM2
-1 to 10 are assigned to POS terminals TM1-1 to 5, POS terminal TM1
-6 to 10, POS terminal TM2-1 to 5, POS terminal TM2-6
4 groups G1, G2, G each with 5 units like ~ 10
3 and G4, and 5 units belonging to the first group G1
The POS terminals TM1-1 to TM5 are connected to the first wireless base station BSU1-1.
Connected to the second group G2 with the radio line R1.
5 POS terminals TM1-6 to 10 to the second wireless base station
A third group is connected to BSU1-2 by radio line R2.
The five POS terminals TM2-1 to TM5 belonging to the
Connected to the radio base station BSU2-1 by the radio line R3,
5 POS terminals TM2-6 belonging to group G4
10 by the fourth radio base station BSU2-2 and the radio line R4
Connected. The first server S1 and the second server S
2 has a common hardware configuration, and as shown in FIG.
PU (Centrl Processing Unit) 11, ROM (Read O
nlyMemoly) 12 and RAM (Random Access Memoly)
The control unit is composed of 13 computer components
I have. Also, the connection is made via the inter-server monitoring signal line SV.
Server interface that inputs signals from the other server
Source 14, the bus-type communication path L (L1 or L2)
Communication that controls data communication with the connected wireless base station
Communication controller 15, the line switch signal C
It has an I / O port 16 for sending to H. further,
Flow, a storage medium that can be read by a computer
Read data stored on the disk 17
FDD (Floppy Disk Dr
ive) 18, Product data files, sales summary files, etc.
Read and write data to the hard disk that forms
External storage device of HDD (Hard Disk Drive) 19
And input of the keyboard 20, the printer 21, the display 22, etc.
Controllers 23 to 27 that control output devices respectively
CPU 11, ROM 12, RAM 1
3, server interface 14, communication controller 1
5, with I / O port 16 and each controller 23-27
Connected by bus lines 28 such as an address bus and a data bus.
Has continued. The first to fourth radio base stations BSU1-1, BSU1-1,
BSU1-2, BSU2-1, and BSU2-2 are hardware components.
As shown in FIG. 3, the CPU 31 and the ROM 3
2 and control by computer mounted parts of RAM 33
Unit. Further, the bus-type communication path L (L1
Or data communication with the server connected by L2)
Communication controller 34 for controlling, for example, 2.4 GHz band
Wireless data communication using the spread spectrum method
The CPU 31 and the ROM
32, RAM 33, communication controller 34, and wireless circuit
35 and bus lines 3 such as an address bus and a data bus.
6 is connected. As shown in FIG.
In particular, each of the error counter EC and the delay set time E0
Forming a memory. Each of the POS terminals TM1-1 to TM10, TM2-1
10 have a common hardware configuration, and as shown in FIG.
Computer of CPU41, ROM42 and RAM43
The control unit is configured by the mounted components. Also, the radio section
Interface 44, and
A wireless slave station 45 is connected to the server 44. In addition,
Reading and data stored on the disk 46
FDD 48 that writes data to the hard disk
External storage device of the HDD 49 for reading and writing data,
Board 50, scanner 51, drawer 52, printer 5
3. Control each POS terminal device such as the display 54.
CPU 55 to 61
1, ROM42, RAM43, wireless interface
44 and each controller 55-61
And a bus line 62 such as a data bus. The RAM 43 stores its own wireless slave station 45.
Information on one main radio base station that performs radio communication with the
Switch when wireless communication with the main wireless base station is disabled
For storing information on one sub-radio base station
A station information memory 63 is formed. Here, the first group
Each of the POS terminals TM1-1 to TM5 belonging to the group G1
As shown in (a), the first server S as a main radio base station
On the first radio base station BSU1-1 connected to
Information, and contacts the second server S2 as a sub radio base station.
The information about the continued third wireless base station BSU2-2 is recorded.
Remember Each POS terminal TM belonging to the second group G2
1-6 to 10 are main radio base stations as shown in FIG.
The second radio base station BS connected to the first server S1
The information on U1-2 is stored, and the second
Fourth radio base station BSU2-4 connected to the server S2 of the
The information about is stored. Each POS terminal belonging to the third group G3
TM2-1 to 5-5 are main radio base stations as shown in FIG.
As a third wireless base station connected to the second server S2
Stores information about BSU2-1 and acts as a secondary radio base station
First radio base station BSU connected to first server S1
The information about 1-2 is stored. Belongs to the fourth group G4
The respective POS terminals TM2-6 to TM10 shown in FIG.
Connected to the second server S2 as the main radio base station
The information about the second radio base station BSU2-2 is stored, and
A second base station connected to the first server S1 as a wireless base station;
Information about the radio base stations BSU1-4 is stored. Thus, the two servers S1, S2
The CPUs 11 use the inter-server monitoring signal line SV to
Monitoring. Here, the CPU 11 of the first server S1
Is transmitted to the second server by the signal of the inter-server monitoring signal line SV.
When the abnormality of S2 is detected, the line switching signal SL1 is turned on.
To disconnect the second server S2 from the communication path L2.
The communication path L2 is connected to the first server S1. And the first
Server S1 replaces the function of the second server S2
Each part is controlled. On the other hand, the CPU 11 of the second server S2
The first server S1 is operated by a signal on the inter-server monitoring signal line SV.
When the abnormality is detected, the line switching signal SL2 is turned on,
The first server S1 is disconnected from the communication path L1, and the communication path
L1 is coupled to the second server S2. And the second service
Server S2 to replace the function of the first server S1.
Section is controlled. The four radio base stations BSU1-1, BSU1-1,
CPU 31 of BSU1-2, BSU2-1, BSU2-2,
The servers connected via the bus-type communication paths L1 and L2, respectively.
Whether the lines with the servers S1 and S2 are normally connected
Is periodically checked by the following program processing. You
That is, the CPU 31 checks the wired communication as shown in FIG.
Of the packet message of the bus type via the communication controller 34
The first server S1 connected by the communication paths L1 and L2 or
The message is transmitted to the second server S2 [p1]. In response,
Response messages from the servers S1 and S2 corresponding within a predetermined time
Is received [YES in p2], an error on the RAM 33
If the counter memory EC is reset to “0”, [p
3], wait for a certain delay time to elapse [p
4]. And if a certain delay time has passed, p1
Return to the corresponding server
To the terminals S1 and S2. The above-mentioned packet communication for confirming the wired communication is transmitted.
As a result, the servers S1, S
If the response message from P2 is not received, [p5
YES], an error has occurred in the communication path or server
The count value of the error counter memory EC is
Count up by “1” [p6]. After a while
Of the error counter memory EC and the RAM 33
Compare the set value of the delay set time memory E0 above.
You. And when the count value has not reached the set value
Waits for a certain delay time to elapse [NO in p7]
[P4]. And if a certain delay time has passed
If it returns to p1, it corresponds to the packet message of the wire communication confirmation again
To the servers S1 and S2. In contrast, an error
The count value of the counter memory EC is the delay set time memory
If the set value of E0 has been reached [YES in p7], the radio
The wireless communication function of the circuit 35 is stopped [p8].
Is completed. Also, each of the 20 POS terminals TM1-1
CPUs 41 to 10 and TM2-1 to 10
3, the main radio base station stored in the base station information memory 63
Base set as a wireless communication partner by information on
Stations BSU1-1, BSU1-2, BSU2-1, BSU2-2 and
It is determined whether or not the wireless lines R1 to R4 are normally connected.
Is periodically checked by the program processing described above. Sandals
That is, the CPU 41, as shown in FIG.
Corresponding to the main radio base station from the radio station 45
Radio base stations BSU1-1, BSU1-2, BSU2-1, BS
It transmits to U2-2 wirelessly [q1]. In response,
Radio base stations BSU1-1 and BSU1 corresponding within a predetermined time
-2, receive response messages from BSU2-1 and BSU2-2
And [YES in q2], wait for a certain delay time to elapse.
[Q3]. And a certain delay time has passed
If it returns to q1, the packet message of the wireless communication confirmation is again
Radio base stations BSU1-1 and BSU1 corresponding to the radio base stations
-2, BSU2-1 and BSU2-2 are transmitted by radio. The wireless communication confirmation packet message is transmitted.
As a result, even if a predetermined time has passed, the corresponding radio base station BS
Response from U1-1, BSU1-2, BSU2-1, BSU2-2
When the answer message cannot be received [YES of q4],
Since an abnormality has occurred in the wireless base station, the base station
Reads information on the sub wireless base station from the information memory 63
[Q5]. And the wireless communication partner is
Switching [q6]. Then, return to q1 and confirm the wireless communication.
Base station corresponding to the secondary main base station
To stations BSU1-1, BSU1-2, BSU2-1, BSU2-2
Transmit by radio. In the first embodiment configured as described above,
In a wireless POS system, for example, the first service
Server S1 has failed and the second server S2 detects the failure.
The line switching signal S from the second server S2.
L2 is turned on. Thereby, the first server S1 communicates.
The communication path L1 is disconnected from the communication path L1, and the communication path L1 is
It is coupled to bus S2. As a result, it is connected to the communication path L1.
The two wireless base stations BSU1-1 and BSU1-2 are connected to a communication path.
Two radio base stations BSU2-1 and BSU connected to L2
As in the case of 2-2, a wired connection is made to the second server S2, and the server
The communication-enabled state with is continued. Also, for example, if the second server S2 fails,
If this failure is detected by the first server S1, the first server
Line switching signal SL1 from the server S1 is turned on.
Thereby, the second server S2 is disconnected from the communication path L2.
The communication path L2 is connected to the first server S1.
You. As a result, the two wireless base stations connected to the communication path L2
The stations BSU2-1 and BSU2-2 are connected to the communication path L1.
Like the two radio base stations BSU1-1 and BSU1-2, the first
Is connected to the server S1 by wire and is in a communicable state with the server.
Is continued. By the above action, either service
If a server fails, the other server fails
Server function can be replaced,
To achieve dualization. Next, the first and second servers S1 and S2
When the shift is also normal, for example, the first wireless base station B
If US1-1 breaks down and wireless communication becomes impossible,
The first wireless base station BUS1-1 is set as a main wireless base station.
In the POS terminals TM1-1 to TM5 of the group G1, no
First radio base station BUS1
-1 wirelessly transmitted, but no response can be received.
Automatically changes the wireless communication partner from the primary wireless base station to the secondary wireless
Switch to base station. As a result, the PO of this group G1
The S terminals TM1-1 to TM5 have no connection with the third wireless base station BUS2-1.
Line communication becomes possible, and this third wireless base station BUS2-1
Data communication with the second server S2 via the
You. Similarly, for example, the second radio base station BUS1
-2 has failed and wireless communication is no longer possible,
Group that uses the second radio base station BUS1-2 as the main radio base station
G2 POS terminals TM1-6 to 10 automatically disable
The wireless communication partner is switched to the secondary wireless base station, and the fourth wireless base station is switched.
Data communication with the second server S2 via the BUS2-2.
It will be. Further, for example, the third wireless base station BUS2
-1 has failed and wireless communication is no longer possible,
3 with the wireless base station BUS2-1 as the main wireless base station
G3 POS terminals TM2-1 to TM5 automatically
The wireless communication partner is switched to the secondary wireless base station, and the first wireless base station
Data communication with the first server S1 via the BUS1-1.
It will be. Further, for example, the fourth radio base station BUS2-2
If wireless communication fails due to a failure,
Group whose primary wireless base station is the wireless base station BUS2-2
G4 POS terminal TM2-6 to 10 automatically wireless
The communication partner is switched to the sub radio base station, and the second radio base station B
Perform data communication with the first server S1 via US1-2
Will be. With the above operation, one of the wireless
If a failure occurs in a local station, the base station is
POS terminal as base station, wireless communication partner is secondary wireless
Automatically switches to the radio base station set as the base station,
Perform data communication with a normal server via a wireless base station.
As a result, there is no need to duplicate radio base station failures.
Can be Next, the first and second servers S1, S2 and
First to fourth wireless base stations BUS1-1, BUS1-2, BU
Example when both S2-1 and BUS2-2 are normal
For example, a first server S1 and first and second wireless base stations BU
Point A of communication path L1 connecting S1-1 and BUS1-2 (see FIG. 1)
If the disconnection occurs in (1), the first and second wireless
In the base stations BUS1-1 and BUS1-2, wired communication
Sent an approved packet message to the first server S1,
The wireless communication function is stopped because a response to
Stop. Thereby, the first and second radio base stations B
US1-1 and BUS1-2 as main wireless base stations
POS terminal TM1 belonging to loop G1 and group G2
-1 to 5 and the POS terminals TM1 to 6 to 10,
Inability to receive a response to a packet confirmation message
From the wireless base station automatically as described above
And the POS terminals TM1-1 to TM5 of the group G1
With the second server S2 via the third wireless base station BUS2-1
Data communication is performed, and the POS terminals TM1-6 of the group G2
10 through the fourth radio base station BUS2-2.
Data communication is performed with the server S2. Also, for example, the second server S2 and third and
Communication connecting the fourth wireless base stations BUS2-1 and BUS2-2
When a disconnection occurs at the point B (see FIG. 1) of the road L2
Are the third and fourth wireless base stations BUS2-1 and BUS2-2.
In, the packet message of the wire communication confirmation is transmitted to the second server.
Sent to server S2 but cannot receive a response to it.
And the wireless communication function is stopped. As a result, this third
And the fourth wireless base stations BUS2-1 and BUS2-2.
Group G3 and group G4 as primary radio base stations
POS terminals TM2-1 to TM5 and POS terminals TM2-6 to which they belong
In the case of ~ 10, for packet message of wireless communication confirmation
Since the response cannot be received, the wireless
The communication partner is switched to the secondary wireless base station, and the PO of group G3 is
The S terminals TM2-1 to TM5 are connected via the first wireless base station BUS1-1.
To perform data communication with the first server S1,
4 POS terminals TM2-6 to 10 are connected to the second wireless base station BUS.
Performing data communication with the first server S1 via 1-2
become. With the above operation, one of the communication paths
If a disconnection occurs at
The wireless base station connected to the communication path
POS terminal does not automatically disconnect.
Wireless base station connected to the other communication path
And a communication path with the server is secured.
Duplication is also achieved for disconnection. By the way, for example, the first server S1 fails.
In this case, the server S1 is connected via the communication path L1.
The connected wireless base stations BUS1-1 and BUS1-2 are connected by wire.
Inability to receive a response to a packet confirmation message
To stop the wireless communication function. This allows this wireless
P with base stations BUS1-1 and BUS1-2 as main radio base stations
OS terminals TM1-1-5 and TM1-6-10 are wireless communication partners.
Are set as the radio base stations BUS2-1 and B set as the sub radio base stations.
Switch to US2-2. As a result, the communication path L1 and the wireless base
Although the stations BUS1-1 and BUS1-2 are not abnormal,
Wireless base stations BUS2-1 and BUS2 connected to communication path L2
-2 The number of POS terminals under the control of
There is concern that performance will be reduced. This means that
The same applies when the second server S2 fails.
Despite the fact that the radio base stations BUS2-1 and BUS2-2 are not abnormal,
Wireless base stations BUS1-1 and BUS1-1 connected to the communication path L1.
As the number of POS terminals under the control of BUS1-2 increases,
System performance may be degraded. Therefore, in the first embodiment,
Are the first to fourth wireless base stations BUS1-1, BUS1-2,
BUS2-1 and BUS2-2 are used to check the line with the server.
It takes a delay set time E0 to detect an abnormality
This delay setting time E0 is caused by a server failure.
Until the line is switched to the other server and communication becomes stable.
By setting the time longer than the required time,
The function of the failed server is correct before the time E0 elapses.
Server is replaced by a normal server, and this alternative server
A response to the acknowledged packet message is returned and an error
Is cleared. As a result, when an error occurs in the server,
Means for detecting abnormalities in wired communication between the
Before operation, the other server detects an error and
Since the means to substitute for the function will work preferentially,
Wireless connected to one server due to failure of one server
The wireless communication function of the base station does not stop, and the other
There is no concern that the load on the wireless base station connected to the
No. Next, there is a connection between the server and the radio base station.
The present invention is applied to a wireless POS system in which a line is looped.
9 to 11 about the second embodiment to which
It will be described using FIG. The first and second servers S1, S
2. First to fourth radio base stations BUS1-1, BUS1-2,
BUS2-1, BUS2-2 and each POS terminal TM1-1-1
0, TM2-1-10 hardware configuration is the first embodiment
Therefore, the description will be made using FIGS. 2 to 6 in common.
Omitted. FIG. 9 shows a wireless P in the second embodiment.
FIG. 1 is an overall diagram of an OS system.
The same reference numerals are given. In other words, it functions as a host device
A first server S1 and a second server S2 that perform
You. Then, the first server S1 is connected via the line switch CH.
And the first wireless base station BS through the loop-type communication path Q1.
U1-1 and the second wireless base station BSU1-2 are connected in order
Then, the second server S2 is routed through the same line switch CH.
The third wireless base station BSU2-1 by the loop-type communication path Q2.
And the fourth wireless base station BSU2-2 are sequentially connected.
You. Then, the first wireless base station BSU1-1 is
And POS terminals TM1-1 to TM1 belonging to the first group G1.
5 via a radio line R1, and a second radio base station BSU1
-2 POS terminal TM belonging to the second group G2
1-6 to 10 are connected by a radio line R2, and a third radio base station B
POS end belonging to the third group G3 with respect to SU2-1
Ends TM2-1 to 5 are connected by a radio line R3, and a fourth radio base station is connected.
P belonging to the fourth group G4 for the local station BSU2-2
The OS terminals TM2-6 to TM10 are connected by a radio line R4. Thus, the two servers S1 and S2
The CPU 11 communicates with the server as in the first embodiment.
They monitor each other using the monitoring signal line SV. here,
The CPU 11 of the first server S1 is a server-to-server monitoring signal line.
Detecting abnormality of second server S2 based on SV signal
And the line switching signal SL1 is turned on, and the second server S2
Is disconnected from the communication path Q2, and this communication path Q2 and other
Communication path Q1 and the first server S
Bind to 1. Then, the first server S1 operates as the second server.
Each part is controlled so as to replace the function of the bus S2. On the other hand, the CPU 11 of the second server S2
The first server S1 is operated by a signal on the inter-server monitoring signal line SV.
When the abnormality is detected, the line switching signal SL2 is turned on,
Disconnect the first server S1 from the communication path Q1 and
Communication path Q1 and the other communication path Q2 into one loop
To the second server S2. And the second server
Each part is changed so that S2 replaces the function of the first server S1.
It is controlled. The first and second servers S1 and S2
The CPU 11 is connected via loop communication paths Q1 and Q2.
Radio base stations BUS1-1, BUS1-2, BUS2-
1. Whether the line with BUS2-2 is connected normally
Is periodically checked by the following program processing. You
That is, as shown in FIG.
Of the packet message connected to the communication controller 34.
[R1] is transmitted to the loop-type communication paths Q1 and Q2. here,
The polling packet transmitted from the first server S1
The sentence is composed of a loop type communication path Q1 and a wireless base station BUS1-1,
When BUS1-2 is normal, the communication path Q1 makes one round and the first
Returned to server S1, sent from second server S2
The polling packet message includes the loop communication path Q2 and the
Communication path when the line base stations BUS2-1 and BUS2-2 are normal
Q2 makes a round and returns to the second server S2.
U11 returns the polling packet message within a predetermined time.
Is detected [YES in r2], a certain delay time elapses
To wait [r3]. And a certain delay time
When the time has elapsed, the process returns to r1, and the polling packet
A loop-type communication path connected to the communication controller 34
Transmit to Q1 and Q2. When the polling packet message is transmitted,
As a result, the polling packet message remains
If not returned [YES in p4], the communication path or
Indicates that an error has occurred in the wireless base station.
A command message is transmitted to the loop communication paths Q1 and Q2.
[P5]. After a while, return to r1 and polling packet again.
To send a loop message to the loop communication path Q1 or Q2.
You. On the other hand, each of the radio base stations BSU1-1 and BSU1
-2, BSU2-1, and BSU2-2 CPU 31 are shown in FIG.
As shown, the servers S1 and S2 which are control stations
Predetermined packet message or error notification command message
It monitors whether it can be received in time. Where
If a polling packet message is received within a fixed time
[YES in s1], Error counter memo on RAM 33
If reset EC is reset to "0" [s2],
Wait for the delay time to elapse [s3]. And one
After the specified delay time has elapsed, the next polling
A packet message or a command message for abnormal notification is sent within a predetermined time.
Monitor whether it can be received. In addition, a command signal for anomaly notification is sent within a predetermined time.
When a sentence is received [YES in s4], it is downstream from itself.
An error has occurred in the communication path or wireless base station on the
Then, the wireless communication function of the wireless circuit 35 is stopped and [s
8], the message monitoring process ends. On the other hand, the polling packet
Neither the reset message nor the error notification command message could be received.
In this case, [YES in s5], the communication
Or an error has occurred in the wireless base station or server.
Only the count value of the error counter memory EC is "1"
Count up [s6]. After a while, this error
Counter value on the counter memory EC
The set value in the delay set time memory E0 is compared. Soshi
If the count value has not reached the set value, [s7
NO], and waits for a certain delay time to elapse [s
3]. And after a certain delay time has passed
Next polling packet message or error notification command
It monitors whether a message can be received within a predetermined time. this
The count value of the error counter memory EC is delayed
When the set value of the set time memory E0 is reached, [s7
YES], the wireless communication function of the wireless circuit 35 is stopped.
[S8], the message monitoring process ends. Further, each of the POS terminals TM1-1 to TM10, TM2
As in the first embodiment, CPUs -1 to 10 are
A line connection confirmation process with the wireless base station shown in FIG.
Has become. In the second embodiment configured as described above,
In the wireless POS system, the servers S1, S
In the case of failure 2, the normal server has failed.
Since the function is substituted, duplication is achieved. Also, the radio base
Stations BUS1-1, BUS1-2, BUS2-1, BUS2-2
In case of failure, the failed wireless base station is
POS terminal automatically changes the wireless communication partner to the normal secondary wireless
Switching to a base station achieves duplication. On the other hand, the first and second servers S1, S2 and
First to fourth wireless base stations BUS1-1, BUS1-2, BU
Example when both S2-1 and BUS2-2 are normal
For example, the first server S1 in the loop communication path Q1
A point A on the upstream side of the wireless base station BUS1-1 (see FIG. 9)
If the disconnection occurs in (1), the first and second wireless
Polling packets for base stations BUS1-1 and BUS1-2
Wireless communication function because messages cannot be received within a predetermined time
To stop. Thereby, the first and second radio base stations
Let the stations BUS1-1 and BUS1-2 be main radio base stations, respectively.
POS terminals TM1-1-5 and POS terminals TM1-6-10
, The response to the packet message of the wireless communication confirmation
Wireless communication partner is automatically set to the secondary wireless
Switch to the base station, and POS terminals TM1-1 to TM5
Data communication with the second server S2 via the base station BUS2-1
And the POS terminals TM1-6 to TM10 are connected to the fourth wireless base station.
Data communication with the second server S2 via the BUS2-2.
It will be. For example, the loop type communication path Q1
B point downstream of the second wireless base station BUS1-2 (see FIG.
9), when the disconnection occurs, the first and second
Polling packet for wireless base stations BUS1-1 and BUS1-2
The first server S can receive the electronic mail message within a predetermined time.
In 1, the polling packet message is not returned
To the first and second wireless base stations BUS1-1, BUS1-2
Sends a command message for error notification to This
And the first and second wireless base stations BUS1-1 and BUS1-2.
, The wireless communication function stops, and the POS terminal TM1-1
5 and TM1-6 to 10 work as described above.
POS terminals TM1-1 to TM5 and TM1-6 to 10
Data communication is performed with the server S2. Further, for example, the loop type communication path Q1
The first wireless base station BUS1-1 and the second wireless base station B
Disconnection occurred at point C (see Fig. 9) between US1-2
The same applies to the case where the first server S1 sends the first and second
Error notification to the local base stations BUS1-1 and BUS1-2
A command message is sent. Thus, the first wireless base station BUS1-1
In, the wireless communication function stops. Also, the second wireless
Polling within base station BUS1-2 within a predetermined time
The wireless communication function has stopped due to the inability to receive packet messages.
Stop. As a result, the POS terminals TM1-1 to TM5 and TM1
-6 to 10 operate as described above, and the POS terminal
TM1-1-5 and TM1-6-10 communicate with the second server S2.
Data communication. The disconnection of the loop communication path Q1 described above
The effect on the second loop type communication path Q2
Similarly, the third wireless base station BUS2-1 is connected to the main wireless base station.
POS terminals TM2-1 to TM5, which are stations, are first radio base stations B
Data communication with the first server S1 via US1-1
And the fourth wireless base station BUS2-2 as the main wireless base station
The POS terminals TM2-6 to 10 are connected to the second wireless base station BUS1-2.
Data communication with the first server S1 via the
You. As described above, in the second embodiment,
Also, as in the first embodiment, either one of the communication paths
If a disconnection occurs at
The wireless base station connected to the communication path
POS terminal does not automatically disconnect.
Wireless base station connected to the other communication path
Switch to a stable communication path with the server.
Thus, redundancy is achieved for the disconnection of the communication path. Moreover, in the second embodiment,
BUS1-1, BUS1-2, BUS2-
1, BUS 2-2 reports that there is an error in the line connection with the server.
Judging from the absence of ring packet messages, wireless communication
It takes delay set time E0 to stop the function
The delay setting time E0 is determined by the server.
The line is switched to the other server due to a failure, and communication is stabilized
By setting the time longer than
In the event of a server failure, wired communication between the server and the wireless base station
Before the means for detecting communication failures are activated, the other server
Means to detect an error and substitute the function of the server
Work properly, so that no
Needless to say, the load on the line base station can be prevented from increasing.
There is no such thing. The loop communication path according to the second embodiment
The first embodiment is also applied to a wireless POS system having
Wireless POS system having a bus-type communication path in the form of
In this way, an error in wired communication between the server and the wireless base station can be detected.
Configuring the wireless base station to have means for detecting
Is also possible. However, in this case, connection to one communication channel
As the number of connected wireless base stations increases,
Since the communication traffic on the communication path increases, the second implementation
As in the form, the wired communication between the server and the wireless base station
The server has means for detecting an abnormality, and the server detects the abnormality.
When detected, notifies the wired base station that there is an error
It is desirable to configure so that In addition, the present invention is applied to a wireless POS system and the like.
The present invention is applicable to other wireless data communication systems.
It is possible to carry out various modifications without departing from the gist of
Of course. As described in detail above, according to the present invention,
Not only failure of the base equipment and the wireless base station, but also
Even if the line connecting to the base station is disconnected,
Ensure a stable communication path between the control terminal and the host device
And stable duplication of wireless data communication systems
realizable.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a wireless PO according to a first embodiment of the present invention.
1 is an overall view of an S system. FIG. 2 is an exemplary block diagram showing a main configuration of a server in the wireless POS system. FIG. 3 is a block diagram showing a main configuration of a wireless base station in the wireless POS system. FIG. 4 is a diagram showing a main memory area formed in a RAM of the wireless base station. FIG. 5 is a block diagram showing a main configuration of a POS terminal in the wireless POS system. FIG. 6 is a configuration diagram of a base station information memory formed in a RAM of the POS terminal. FIG. 7 is a flowchart showing base station = server line confirmation processing executed by the CPU of the wireless base station in the wireless POS system. FIG. 8 is a flowchart showing POS = base station line confirmation processing executed by the CPU of the POS terminal in the wireless POS system. FIG. 9 shows a wireless PO according to a second embodiment of the present invention.
1 is an overall view of an S system. FIG. 10 is a flowchart showing server = base station line confirmation processing executed by the CPU of the server in the wireless POS system according to the second embodiment; FIG. 11 is a flowchart showing base station = server line confirmation processing executed by the CPU of the wireless base station in the wireless POS system according to the second embodiment; [Description of References] S1, S2: First and second servers (upper devices) CH: Line switchers BUS1-1, BUS1-2: First and second wireless base stations BUS2-1, BUS2-2 ... Third and fourth radio base stations TM1-1 to TM10, TM2-1 to 10 POS terminals (controlled terminals) L1, L2 Bus-type communication paths Q1, Q2 Loop-type communication paths EC Error counter memory E0 ... Delay setting time memory 63 ... Base station information memory

Claims (1)

(57) [Claims 1] A different wireless base station is connected to at least two higher-level devices by wires, and a plurality of controlled terminals controlled by the higher-level devices are connected to the respective wireless terminals. Providing a wireless slave station capable of wireless communication with the base station,
In a wireless data communication system in which data communication between a higher-level device and each controlled terminal is performed wirelessly, when each higher-level device monitors each other and detects an abnormality in the other higher-level device, the higher-level device itself becomes the other side. A wireless base station wired to at least one of the higher-level devices has means for substituting the function of the higher-level device, and means for detecting an abnormality in wired communication with the higher-level device. Means for stopping the wireless communication operation when detecting an abnormality in the wired communication of the wireless terminal and disabling wireless communication with the wirelessly connected wireless slave station. Each controlled terminal wirelessly communicates with its own wireless slave station. Means for storing information on one main radio base station and information on at least one sub radio base station to be switched when radio communication with the main radio base station is disabled; Means for switching a wireless communication partner from the main radio base station to the sub-radio base station when radio communication is disabled, and the main radio base station and the sub-radio base station are wired to different upper-level devices, respectively. In the event of an abnormality in the higher-level device, the other higher-level device is connected to the higher-level device by wire before the means for detecting an abnormality in wired communication with the higher-level device operates. A wireless data communication system, wherein means for detecting an abnormality of a device and substituting the function of the higher-level device works preferentially.