JPH01200473A - Transmission and reception device for pos system - Google Patents

Abstract

PURPOSE:To lower the probability by which communication becomes impossible by changing a transmission frequency and executing the communication with other terminal controller, when an error has been generated in a radio communication state of a terminal and a terminal controller. CONSTITUTION:Each terminal controller TC1, TC2..., TCn which has been brought to in-line connection to a store controller 1 executes radio communication with the corresponding terminals T12...T1n, T21...T2n by transmission frequencies X1, X2... respectively. In this state, for instance, when a reception request is outputted to the controller TC1 from the terminal T11 and a state that it does not become receivable is repeated two times, etc., and AND gate 7 is selected and opened by a selecting signal 6 of a transmission frequency switching means 4 of the terminal T11 and switched to a transmission frequency X2, etc., except the frequency X1, and between the controller TC2, etc., except the controller TC1 and the terminal T11, radio communication is executed. By switching this communication frequency, the probability by which communication becomes impossible is lowered.

Description

[Detailed description of the invention] Industrial application field The present invention is applicable to PO in department stores, supermarkets, etc.
This relates to a transmitting/receiving device of the S system.

BACKGROUND ART Conventionally, a plurality of terminal controllers connected in-line to a store controller are each provided with a plurality of terminals so as to be able to communicate via wireless communication means. In this way, when the communication means is wireless communication, data communication errors may occur due to causes such as jamming radio waves, blocking of radio waves by physical obstacles, and failure of the receiver.

In such a case, transmission and reception are performed again using the same frequency a preset number of times.

The problem that the invention seeks to solve is that even if transmission and reception are repeated multiple times using the same frequency,
Communication is often impossible depending on the cause of data communication, and there is a high probability that the communication line is defective.

In such a case, there is a large loss of time due to repeated transmission and reception.

Means for Solving the Problem A plurality of terminal controllers are provided in-line connected to the store controller, and each of these terminal controllers is provided with a plurality of terminals that are capable of communicating via wireless communication means. Transmission frequency dispersion switching means is provided for changing the transmission frequency to enable communication with other terminal controllers when an error occurs in the wireless communication state between the terminal and the terminal controller.

When an error occurs during wireless communication, the transmission and reception are performed by switching to another transmission frequency, so the probability of communication failure is extremely low. It is designed to eliminate time loss when transmitting and receiving data.

Example An embodiment of the present invention will be described based on the drawings.

First, for store controller 1, TC,,TC,...
n terminal controllers 2 indicated as TC, . . . TCn are connected in-line.

Wired communication is performed between the store controller 1 and the terminal controller 2 according to a certain agreement.

Then, in each of the terminal controllers 2, Tl l I Tl m 1 T + s "'"
・T + n or T2. .

T**+ 'r, . . . n terminals 3 are connected like T, n. And between these terminals 3 and the terminal controller 2,
It is provided so that it can transmit at a specific transmission frequency set for each group. For example, TC, terminal 2 and T ill 'r, □, T,...
...The transmission frequency is X between the terminal controllers 3, T and n, and the transmission frequency is , has been selected to be. And Terminal 3 as mentioned above,
These are cash registers and electronic fare scales used in department stores and supermarkets.

Next, the transmission frequency switching means 4 will be explained based on FIG. First, X,,X,,X,...Xn becomes n
oscillators 5, CH,, CH,, CH,...C
n channel selection means 6 denoted as Hn are connected to an AND gate 7 for each channel, and these AND gates 7 are connected to an OR gate 8, and the output of this OR gate 8 is multiplied with communication data. It is connected to a transmitter 10 via an AND gate 9.

In such a configuration, when transmitting data from the first group of terminals 3 to the terminal controller 2, a communication channel is opened at the transmission frequency X.

Then, the terminal 3 outputs a data reception request to the terminal controller 2. Then, the terminal controller 2 outputs the receivable state to the terminal 3, and if the terminal controller 2 is in the receivable state, the terminal 3 outputs data to the terminal controller 2. When the output of this data is completed, a data end signal is outputted, and the process ends when the terminal controller 2 receives the data output end signal.

Therefore, in the above-mentioned routine, if the terminal controller 2 is not in a receiving state even if a request for data reception is output from the terminal 3 to the terminal controller 2, that is, if the radio waves are blocked by interference waves or physical obstructions,
If reception is not possible due to a receiver failure, etc., a request to receive data is output again. If the terminal controller 2 becomes ready to receive data due to this second request to receive data, it will operate normally as described above, but if it still does not become ready to receive data even after making the second request to receive data, In this case, a channel other than the transmission frequency X1 is selected by the channel selection means 6, and the channel is opened at that transmission frequency.

This allows terminal controller 2 of other groups to
Data is transmitted using.

Such an operation is performed when the terminal controller 2 is in a reception ready state and the terminal 3 is outputting data, and if a data output end signal is output from the terminal 3, the terminal controller 2 will terminate the data output. Even when no signal is received, a check is made to see if the "data output end signal" is the second time, and if it is the second time, switching to another transmission frequency is performed.

In the above embodiment, a case was explained in which the following questions are checked: "Is this the second time a data reception request has been output?" and "Is this the second time a data output end signal has been output?" When the terminal controller 2 is not ready for reception, or when the terminal controller 2
When the data output end signal is not received, switching to another transmission frequency may be performed immediately.

Effects of the Invention As described above, the present invention provides a plurality of terminal controllers connected inline to a store controller,
Each of these terminal controllers is provided with a plurality of terminals that can communicate via wireless communication means, and when an error occurs in the wireless communication status between these terminals and the terminal controller, the transmission frequency is changed. We have provided a transmission frequency switching means that enables communication with other terminal controllers, so if an error occurs during wireless communication, the transmission frequency will be switched to another transmission frequency and transmission/reception will be performed, so the probability of communication being unavailable is extremely low. This has the effect that it is possible to communicate with other terminal controllers using other transmission frequencies and eliminate time loss in data transmission and reception.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a block diagram, FIG. 2 is a circuit diagram of a transmission frequency switching means, and FIG. 3 is a flow chart. 1... Store controller, 2... Terminal controller, 3... Terminal, 4... Transmission frequency switching means Applicant: Tokyo Electric Co., Ltd.

Claims (1)

[Claims] A plurality of terminal controllers are provided in-line connected to the store controller, and each of these terminal controllers is provided with a plurality of terminals that are capable of communicating via wireless communication means, and communication between these terminals and the terminal controller is provided. 1. A transmitting/receiving device for a POS system, comprising a transmitting frequency switching means that changes the transmitting frequency to enable communication with another terminal controller when an error occurs in a wireless communication state.