JP3746385B2 - Communication system with clock adjustment function - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a communication system in which a plurality of card input terminals are communicatively connected to a data collector (such as a personal computer). Specifically, the time of internal clocks of all card input terminals can be unified. The present invention relates to a communication system having a clock adjustment function devised so that it can be performed.
[0002]
[Prior art]
Various card input terminals such as time recorder terminals, door opening / closing control terminals, or meal data input terminals have their own internal clocks, and the time for inputting attendance data and the time for unlocking or locking door electric locks. Alternatively, each time data such as the input time of the meal data has a structure determined by the internal clock when the personal identification card is inserted.
[0003]
On the other hand, in a communication system in which a plurality of card input terminals as described above are connected to a data collector, an error occurs in the internal clock of each card input terminal, and after a certain period of time, Since the time will be scattered, the current time of all the card input terminals is unified by sending the clock data to all the card input terminals by broadcast communication from a data collector such as a personal computer. It is configured as follows.
[0004]
[Problems to be solved by the invention]
However, looking at the accuracy of the clock, the error of a card input terminal such as a time recorder is 3 seconds per week, whereas the error of a personal computer is generally 20 seconds or more per week. Because the internal clock of the personal computer becomes less accurate than the internal clock of the card input terminal, if the clock data of the personal computer is simply sent to the card input terminal by simultaneous broadcast communication, the time deviation will increase on the contrary. There was a problem that let me.
[0005]
Therefore, the technical problem of the present invention is that a card with higher accuracy can be obtained without using the conventional unreasonable method of setting the time of the card input terminal to the internal clock of the data collector (such as a personal computer) with lower accuracy. The current time is unified based on the internal clock of the input terminal.
[0006]
[Means for Solving the Problems]
In order to solve the above technical problem, a communication system having a clock adjustment function according to the present invention includes a plurality of card input terminals that are slave stations of a data collector that is a master station, and the data collection A communication system configured to send various data including time data from the card input terminal to the data collector in response to a request from the machine,
At least one of the multiple card input terminals has a reference clock, and other card input terminals receive clock data from the card input terminal having the reference clock to the data collector. Registering the address of the card input terminal that has the reference clock as the setting parameter, the communication intercepting means for intercepting the clock data, the clock setting means for setting the intercepted clock data to the internal clock Parameter registration means, and when the request data sent from the data collector has a description of its own address and a request for time data, the time data of its own device is stored in the data collector. When the other device address is in the above request data and the other device address is the address of the card input terminal having the reference clock Intercepts a reference clock data transmitted from the card input terminal with the reference clock, is characterized by being configured to set the internal clock of the own apparatus.
[0007]
According to the above means, the communication data to the slave station from the master station, data request type, communication address is described in the slave station which has received the communication data, the specified address of the communication data is its own device address, When there is a request for time data, the time data of the own device is sent to the data collector. On the other hand, if the specified address of the communication data is an address of another device and is identified as a card input terminal having the reference clock, it is transmitted from the input terminal having the reference clock. Since it is configured to intercept the reference clock data and set it to the internal clock of its own device, the system can be configured without entrusting the time adjustment of the entire system to a personal computer with poor clock accuracy (for example, a commercially available personal computer). It is possible to configure a system that uses a highly accurate time of a reliable terminal (a highly reliable product provided by a manufacturer).
[0008]
Furthermore , according to the above means, in addition to normal data collection in the master station, the terminal having the reference clock is requested to transmit time data, and each time of the slave station can be adjusted. A simple system can be configured. In addition, since it has parameter registration means for registering the identification code of the card input terminal having the reference clock in the setting parameter, it is easy to determine which terminal is the reference terminal.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of a communication system having a clock adjustment function according to the present invention will be described below with reference to the drawings. FIG. 1 is a communication wiring diagram illustrating the whole of the present invention. The data collector used, 2 is a converter, 4A, 4B... 4N are card input terminals connected to the data collector 1 using the communication line 3, and the communication procedure is to use the data collector 1 (PC) as the main station. In the illustrated case, a reference clock is incorporated in the second card input terminal 4B.
[0010]
2 is a perspective view for explaining the external appearance of each of the card input terminals 4A, 4B,... 4N. In the figure, 5 is a display for displaying the current time and other messages, 6 is an ID card using a magnetic card, etc. A card insertion slot through which (not shown) is inserted, 7 is a keyboard, and 8 is a key lamp. Is constituted by display lamps 8A, 8B, 8C and 8D which are turned on when these keys 7A to 7D are turned on.
[0011]
3 is a block diagram illustrating the electrical configuration of each of the card input terminals 4A, 4B,... 4N. In the figure, 10 is a CPU constituting the center of the control unit, 11 is a bus connected to the CPU 10, and this bus 11, a ROM 12 storing a system program, a RAM 13 storing a personal file, a transmission driver 14 and a reception driver 15, and an interface circuit 16 are connected to each other, and a communication line 3 connected to both the drivers 14 and 15 is connected. Are connected to the data collector 1 described above.
[0012]
Further, the interface circuit 16 reads personal information from an ID card or the like inserted through the card insertion slot 6 in addition to the display unit 5, keyboard 7 and key lamp 8 described above, or from a setting card or the like. Sets card input device 6T for reading setting information, sounding device 9 for generating various messages and alarm sounds, internal clock 17A or internal clock 17B as a reference clock, and terminal number (communication address) of own device The DIP switch 18 used for this is connected.
[0013]
Further, in the ROM 12, a program for registering the value of the communication address (= 02) of the card input terminal 4B provided with the reference clock 17B as a parameter in the RAM 13 using the setting card and the keyboard 7 ( Parameter registration means) is stored and a card input terminal having a reference clock 17B for unifying the time from among the card input terminals 4A... 4B can be easily designated or confirmed.
[0014]
Further, the ROM 12 has a program (communication interception means) for intercepting (receiving) the clock data when the clock data is transmitted from the card input terminal 4B having the reference clock 17B to the data collector 1. A program (clock setting means) for setting the intercepted clock data in the internal clock 17A of the own machine is stored, and the time of the internal clock 17A of the own machine can be automatically adjusted to the time of the reference clock 17B. It is configured.
[0015]
The above data collector 1 periodically sucks up the attendance data of the card input terminals 4A, 4B... 4N, and when the attendance data disappears in the card input terminals 4A, 4B... 4N, the card input terminal 4B always has the reference clock 17B. In addition, the time data processing process is performed sequentially for each of the card input terminals 4A, 4B,... 4N.
[0016]
In the illustrated embodiment, the internal clock of the second card input terminal 4B is used as the reference clock 17B, but this is an example of implementation, and the card input terminals 4A other than the second card input terminal 4B. A 4N internal clock may be used as a reference clock, and its selection is arbitrary.
[0017]
4 is a communication format of inquiry data transmitted from the data collector 1, and FIGS. 5 and 6 are communication formats of attendance data and clock data transmitted from the respective card input terminals 4A, 4B... 4N.
[0018]
Next, the processing procedure of the clock adjustment by the communication system having the clock adjustment function according to the present invention described above will be described with reference to the state transition diagram shown in FIG.
[0019]
When the ENQ is received from the standby state in step S1, the process proceeds to step S2, and the communication address sent from the data collector 1 is analyzed. If the communication address is the own address, the process proceeds to step S3 to collect data. The data request type from the machine 1 is checked. As a result, if the requested data is attendance data, the process proceeds to step S4 and the attendance data in the data memory 13 is read.
[0020]
If there is no attendance data as a result of reading in step S4, the process returns to step S1 in the standby state described above. If there is attendance data, the process proceeds to step S5 to transmit attendance data to the data collector 1 (personal computer). When the process proceeds to step S6 waiting for a response and an affirmative response is received from the data collector 1, the process returns to the above-described step S4 to read out the next attendance data, and when a negative response is received, the process returns to step S5. Return to, and repeat the transmission process.
[0021]
If the clock data is requested in step S3 described above, the process proceeds to step S7 to read the clock data from the internal clock 17A, and then proceeds to step S8 to transmit the clock data to the data collector 1. The process proceeds to step S9 waiting for a response, and if an affirmative response is received from the data collector 1, the process returns to the standby state of step S1, but if a negative response is received, the process returns to step S7 to read the clock data. And the transmission process is repeated.
[0022]
On the other hand, if the communication address is the other device address in the second step S2 described above, the process proceeds to step S10, whether or not the communication address is = 02 (value registered in the setting parameter), that is, the communication address. Is determined to be the card input terminal 4B having the reference clock 17B. If NO, the process returns to step S1 in the standby state described above. If YES, the process proceeds to next step S11.
[0023]
In step S11, the clock data of the reference clock 17B transmitted by the other device 4B is intercepted. When the clock data is normally intercepted, the process proceeds to step S12 and the intercepted clock data is sent to the internal clock 17A of the own device. The time is set and the time is set, but if there is a reception error, the process returns to step S1 in the standby state.
[0024]
If a reception error occurs in the above step S11, the intercepted clock data is discarded and not set in the internal clock 17A of the own device, but the data collector 1 is connected to the card input terminal 4B having the reference clock 17B. Since the clock data is frequently requested, even if a reception error occurs, it can be normally received while repeating the intercept several times.
[0025]
In the above-described embodiment, the current time of all the card input terminals 4A... 4N can be unified, but if the reference clock 17B of the card input terminal 4B goes wrong, the keyboard 7 described above is used. Thus, the reference clock 17B can be set to the correct time.
[0026]
FIG. 8 is a configuration diagram clearly showing the entire communication system having a clock adjustment function according to the present invention.
[0027]
【The invention's effect】
As described above, according to the communication system having a clock adjustment function according to the present invention, data collection is performed using an internal clock of a card input terminal such as a time recorder with higher accuracy than a data collector (personal computer) as a reference clock. The time of all card input terminals connected to the machine can be unified to a more accurate time, and among the internal clocks provided in the card input terminal, the accuracy of internal clocks other than the internal clock serving as the reference clock is low. Therefore, it is economical to reduce the manufacturing cost of the entire apparatus.
[Brief description of the drawings]
FIG. 1 is a communication wiring diagram illustrating an entire communication system having a clock adjustment function according to the present invention.
FIG. 2 is a perspective view showing an example of a card input terminal used in the present invention.
FIG. 3 is a block diagram illustrating an electrical configuration of a card input terminal.
FIG. 4 is a communication format of inquiry data.
FIG. 5 is a communication format for attendance data.
FIG. 6 is a clock data communication format;
FIG. 7 is a state transition diagram explaining a processing procedure of the present invention.
FIG. 8 is a configuration diagram clearly showing the whole of the present invention.
[Explanation of symbols]
1 Data collector (PC)
4A, 4B ... 4N Card input terminal 17A Internal clock 17B Reference clock

Claims (1)

Various data including time data from the card input terminal to the data collector in response to a request from the data collector in communication connection with a plurality of card input terminals which are slave stations of the data collector as the main station A communication system configured to send
At least one of the multiple card input terminals has a reference clock, and other card input terminals receive clock data from the card input terminal having the reference clock to the data collector. Registering the address of the card input terminal that has the reference clock as the setting parameter, the communication intercepting means for intercepting the clock data, the clock setting means for setting the intercepted clock data to the internal clock Parameter registration means, and when the request data sent from the data collector has a description of its own address and a request for time data, the time data of its own device is stored in the data collector. When the other device address is in the above request data and the other device address is the address of the card input terminal having the reference clock , Communication system having a clock adjustment function, characterized in that intercepting the reference clock data transmitted from the card input terminal with the reference clock, and configured to set the internal clock of the own apparatus.

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