JPH028509B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a system in which, when an unmanned terminal in an information processing system has a calling function to a center, the center can check whether there is an abnormality in the calling function.

As shown in Figure 1, multiple unmanned terminals TM are used as an information processing system via public telecommunications circuits.
1, TM2... are connected to the information processing center DPC. FIG. 1 shows a switched network NWK as a public telecommunications line, and a network control unit NCU is provided on the switched network side of the center and each terminal. For example, in the case of a terminal with a pollution monitoring device, sensor SNS
The information detected by the terminal is temporarily held in the terminal, and the center DPC sequentially calls each terminal at predetermined time intervals to collect the information, which is called polling. When a terminal malfunctions or a sensor detects an extreme abnormality, it is necessary for the terminal TM to notify the center DPC of emergency information, so at that time the terminal TM automatically makes an outgoing call, which is called calling. The configuration of the information processing center DPC and the terminal TM is shown in blocks as shown in FIG. 2, a sequence diagram when they perform polling is shown in FIG. 3, and an example of the data transmission format is shown in FIG. 4. These configuration diagrams and sequence diagrams are well known, and the data transmission format shown in FIG. 4 is also common. In Figure 4, ST is the start bit, SP is the stop beat, P1 is the odd parity bit, and P2
is even parity bit, downlink data flag F1
is a return request flag, and when it is "1" it indicates that a return request is made, and when it is "0" it indicates that return is not required. The flag F2 of the upstream data indicates that the final word flag is "1" when it is a working word, and when "0" it indicates that it is the final word. Since calling operations occur less frequently than polling operations, the center usually does not have a means to check whether the calling function of the terminal is normal. Note that the response when a terminal is polled is different from that of the calling function, so it cannot be determined that the instant calling function is also good just because the terminal responds normally to polling.

An object of the present invention is to provide an information processing center when desired;
To provide a method for easily checking the calling function of an unmanned terminal.

Embodiments of the present invention shown in the drawings will be described below. FIG. 6 shows a data transmission format when implementing the present invention, FIG. 5 shows a sequence diagram, and FIG. 7 shows an operation timing chart. In FIG. 6, as a transmission format for downlink data, for example, the first 1 bit out of the 16 bits of data in FIG. 4 is used as a calling check flag bit F3 for a calling function check. For example, when the flag F3 following the return request flag F1 is "1", it is a calling check,
“0” indicates other cases. The other bits of the transmission format and the upstream data format are the same as those shown in FIG. The information processing center DPC activates a calling check on the terminal when desired according to the sequence shown in FIG. network control device
After the NCU detects activation, the center dials the terminal number. When a call arrives at the terminal TM and is automatically answered, a polarity inversion signal is returned to the center side network control device. The center knows that the connection to the terminal is completed, and sends the data for the calling check shown in FIG. 6 to the terminal. After sending this data, the center disconnects the line. The terminals are also immediately placed in an off-hook state, and the loop is released from each other. When the terminal receives the data for the calling check, the processor MPU decodes it and recognizes the calling check flag, so it knows that it is in the calling check state. The terminal therefore initiates a call to the center. In other words, it is placed in an off-hook state and automatically dials the center number. Thereafter, when the center knows that the connection to the center DPC is complete and sends the calling check data in the normal procedure, the center checks the data and returns a confirmation number. The terminal terminates the calling operation and goes on-hook using this confirmation number.

The timing chart shown in FIG. 7 shows the generation and disappearance times of each signal at the center and terminals. The operation of the present invention is characterized in that the center activates the terminal by polling for calling check, and when the terminal responds, all line connections are released, and then the terminal waits for operation.

In this way, according to the present invention, the reliability of the information processing system is improved because the calling function of the terminal can be checked from the center at any desired time with a simple configuration that includes means for determining transmission data for calling check in the terminal. It can be greatly improved.

[Brief explanation of drawings]

Figure 1 is a connection diagram of a communication system that connects multiple terminals and an information processing center, Figure 2 is a block diagram showing the main parts of Figure 1, and Figure 3 is the conventional polling operation sequence shown in Figure 1. diagram,
FIG. 4 is a diagram showing the transmission format of data used during the operation of FIG. 3, and FIG. 5 is a diagram showing the transmission format of downlink data in the embodiment of the present invention.
FIG. 6 shows an operation sequence diagram in an embodiment of the present invention, and FIG. 7 shows an operation timing chart of FIG. 6. DPC...Information processing center, NWK...Telephone switching network, NCU...Network control device, TM, TM1, TM2
...Terminal, SNS1, SNS2...Sensor, DRV...
…Data driver, RCV…Data receiver,
MDM...modulator/demodulator, PS/SP...data serial/parallel converter, CPU, MPU...processor.

Claims (1)

[Scope of Claims] 1. A plurality of unmanned terminals are provided that are connected to an information processing center only via public communication lines, and the information processing center is equipped with a polling function, and each terminal is equipped with a polling function, and each terminal can automatically make calls to the center as necessary. In a system having a calling function for transmitting information, a calling check flag bit is provided in the transmission format transmitted between the information processing center and each terminal, and the information processing center performs a calling check on a predetermined terminal. The calling check flag bit in the transmission format is turned on, the specified terminal is polled and the line is temporarily disconnected, and the terminal identifies the calling check flag bit in the transmission format and automatically sends a call to the information processing center. A system for checking the calling function of a terminal in a system, characterized in that the information processing center receives the data and checks the calling function of the terminal.