JP2741567B2 - Read data judgment method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method in which a signal level is recorded on a card as a first value which changes once every predetermined time and a second value which changes twice every predetermined time. In this case, the present invention relates to a read data judgment method for judging the first and second values by reproducing the binary data recorded on the card.

[0002]

2. Description of the Related Art Conventionally, on a magnetic card used in a public telephone or the like, value information is recorded in advance as magnetic data. The values of "0" and "1" of the binary data signal indicating the value information are determined as follows.
That is, for example, a signal that changes once every 400 μsec is “0”, and a signal that changes twice (that is, 200 μsec).
(a signal that changes once every c) is defined as “1”. Here, when a call is made using a magnetic card in the public telephone, first, value information remaining on the card is read out as follows. That is, the card value information is first read out sequentially as a time value for each change point of the signal and stored in the memory. Next, the magnitude of each time value stored in the memory is determined by a reference value such as 300 μsec. That is, 200 μm is used when the time is shorter than 300 μsec, and 400 μm when the time is longer than 300 μsec.
sec. After the magnitude relationship with the reference value is determined in this way, binary data indicating the value information is determined. Then, a call corresponding to the binary data is permitted, and when the call is terminated, the value information corresponding to the call is subtracted from the value information, and the remaining value information on the magnetic card is recorded at the same timing. You.

[0003]

Conventionally, when binary data recorded on a card is read to determine "0" or "1", the determination is made according to a predetermined reference value. Variations occur in the time value of the reproduction signal due to variations in the read head that reads the card data. As a result, the binary data is erroneously determined, and the value information recorded on the card cannot be accurately detected.

Accordingly, an object of the present invention is to prevent erroneous determination of binary data of a magnetic card, and to accurately detect value information of the card.

[0005]

In order to solve such a problem, the present invention provides a first value in which the signal level changes once every predetermined time and a second value in which the signal level changes twice every predetermined time. Is recorded on the card as binary data having the value of, and when the binary data of the card is reproduced to determine the first and second values, when the card is inserted, the signal change point from the inserted card Each time value is sequentially read, a central value of all the read time values is determined, and a magnitude relationship between the central value and the total time value is determined. First and second values are determined according to the determined magnitude relationship. Is determined.

[0006]

The time value at each change point of the signal is read from the inserted card, the center value of all the read time values is determined, and the magnitude relation between the total time value and the center value is determined. One of the first and second values is determined according to the magnitude relationship. As a result, even if the recording data of the card varies or the read head varies, erroneous determination of the binary data of the card is prevented, and thus the value information of the card can be accurately detected.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 7 is a sectional view of a card reader / writer device to which the read data determination method according to the present invention is applied. In FIG. 1, reference numeral 1 denotes a magnetic card, and reference numeral 2 denotes a card reader / writer for recording / reproducing and punching magnetic data on / from the magnetic card 1. Here, the card reader / writer device 2 is configured as follows. That is, 21 is an insertion / ejection port through which the magnetic card 1 is inserted and ejected, 22 is a card conveyance path for conveying the magnetic card 1, and 23 is a recording head (write head) and a read head (reproduction head). A head for recording and reproducing magnetic data,
Reference numeral 24 denotes a punch unit for punching the magnetic card 1;
A sensor 5 detects the position of the magnetic card. Also,
26A and 26B are rollers, 27 and 29 are belts, 28 is a pulley, and M is a motor. Here, when the motor M rotates, this rotational force is transmitted to the pulley 28 via the belt 29, and the pulley 28 rotates. The rotation of the pulley 28 rotates the rollers 26A and 26B interlocked with the rotation, and as a result, the magnetic card 1 on the belt 27 is transported on the card transport path 22.

FIG. 1 is a block diagram of a control system of the card reader / writer device.
A control circuit 31 such as U is connected via a transmission / reception circuit 32 to a control unit 30 that controls a higher-level device such as a public telephone, for example. The control circuit 31 is connected to the head unit 23, the punch unit 24, the sensor unit 25, and the motor M as well as an EEPROM 33 for storing and holding various parameters necessary for control, and a ROM 34 for storing programs. , The contents of which are stored and held by a backup power supply from the control unit 30
5, a shutter unit 36, an optical sensor 37 for detecting a bar code attached to the magnetic card 1, and an encoder 38 for detecting the rotation speed of the motor M, that is, the transport speed of the magnetic card 1, are connected.

When the magnetic card 1 is inserted into the insertion / ejection port 21 shown in FIG.
To rotate the pulley 28 and the roller 26
Rotate A. As a result, the roller 26A and the belt 27
The roller 26B connected by the rotation also rotates, and the inserted magnetic card 1 on the belt 27 is transported to the position where the head unit 23 is disposed.

Thereafter, the control circuit 31 instructs the head unit 23 to read magnetic data indicating the value information of the magnetic card 1 with the read head. Then, for example, during a telephone call, every time a billing signal arrives, certain value information is subtracted from the read magnetic data.
3, the value information remaining on the magnetic card 1 is magnetically recorded by the recording head. Then the control circuit 31
Rotates the magnetic card 1 so as to be conveyed in the direction of the insertion / ejection port 21 to convey the magnetic card 1 to the position of the punch portion 24, and drives the punch portion 24 to respond to the residual value information of the magnetic card 1. Punch position.
Thereafter, the magnetic card 1 is conveyed to and discharged from the insertion / ejection port 21 while monitoring the output of the sensor unit 21 for detecting the position of the magnetic card 1.

FIG. 2 is a diagram showing the configuration of the magnetic card 1, and the magnetic card 1 is provided with a data section 1A in which the above-described magnetic data is recorded. FIG. 3 is a diagram showing the timing of magnetic data recorded and reproduced by the head unit 23 on the magnetic card 1. As shown in the drawing, data “1” recorded on the magnetic card 1 is data (400 μs) that changes every 200 μsec as a time value, for example.
(data that changes once during ec). Data “0” recorded on the magnetic card 1 is data (40) that changes as a time value, for example, every 400 μsec.
It is recorded as unchanged data during 0 μsec. It should be noted that the magnetic card 1 is reproduced at the same timing when reproducing the magnetic data.

By the way, when the magnetic data defined at the above timing is actually reproduced as a time value at each change point, as shown in FIG. The reproduced time value varies. For this reason, even if each time value detected by each card is to be classified into "0" and "1" by a predetermined reference value, data "0" in one card is classified into "1" in another card. This causes the problem that Therefore, when the magnetic data is reproduced from the data section 1A of the card 1, the control circuit 31 determines the center value of all the time values of the actually reproduced magnetic data (actually, 16 in FIG. 4).
Each time value distributed from 0 to 240 μsec and 340 to
It is determined as an intermediate position between each time value distributed in 240 μsec) and based on this center value, 16 in FIG.
Each time value distributed in the range of 0 to 240 μsec is determined as, for example, a candidate for data “1”, and the time value of 340 to 240 μs in FIG.
Each time value distributed in ec is determined as data “0”.

FIG. 5 is a flow chart showing a main part of the operation of the apparatus of the present embodiment. The data recorded on the magnetic card 1 is reproduced and any one of binary signals "0" and "1" is reproduced. 3 shows the operation of the control circuit 31 for judging. That is, when the inserted magnetic card 1 is transported to the position of the head section 23, the control circuit 31 controls the head section 23 to read magnetic data from the data section 1A of the magnetic card 1 in step ST1. In this case, the control circuit 31
Starts a timer (not shown) for each change point of the magnetic data reproduced by the head unit 23 and measures the time until the next change point. Subsequently, in step ST2, the read level value of the change point and the time value of the timer are stored in the memory (RAM 35).

In step ST3, the end of the data reading is determined. If the reading is not completed, the reading operation is continued, and the level value and the time value of each change point are sequentially stored in the memory. When the reading of the magnetic data from the data section 1A and the storage of the read data in the memory are completed, and the determination in step ST3 becomes "Y", a reference value is calculated from the stored data in the memory in step ST4. That is, the central value of each stored time value is calculated and determined as a reference value. Next, in step ST5, the magnitude of all the time values stored in the memory with respect to this central value is determined.
That is, the length is determined. If the length is longer than the reference value, for example, the data is determined to be “0”, and if the length is shorter than the reference value, the data is determined to be “1”. Thus, the magnetic card 1 2
The value data is determined.

In this manner, the data portion 1 of the magnetic card 1
Since the center value is determined from the actually reproduced data of A, as shown in FIG. 6, even if the distribution of the time values differs for each card, the center value is determined as indicated by the arrow in the figure. An appropriate reference value can be set for each case. As a result, even if there is a variation in the data of each card or a variation in each head, the binary data of the card can be determined regardless of the variation, and therefore, the value information of the magnetic card can be accurately detected.

[0016]

As described above, according to the present invention, the time value at each signal change point is read from the inserted card, the center value of all the read time values is determined, and the center value is set for the entire time value. Since the magnitude relationship with the value is determined and which of the first and second values of the binary data of the card is determined according to the determined magnitude relationship, the variation in the recorded data of the card or the reading of the card is determined. Even if head variation occurs, erroneous determination of binary data recorded on the card can be prevented,
Therefore, there is an effect that the value information of the card can be accurately detected.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of an apparatus to which a read data determination method according to the present invention is applied.

FIG. 2 is a diagram showing a configuration of a card used in the device.

FIG. 3 is a timing chart showing time values of magnetic card data recorded / reproduced in the apparatus.

FIG. 4 is a diagram showing variations in the magnetic card data.

FIG. 5 is a flowchart showing the operation of the above device.

FIG. 6 is a diagram showing a state of discrimination of magnetic card data by the device.

FIG. 7 is a sectional view of the device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 magnetic card 1A data section 2 card reader / writer 21 insertion / ejection port 22 card transport path 23 head section 24 punch section 25 sensor section 31 control circuit (CPU) 38 encoder M motor

Claims (1)

(57) [Claims] 1. A first value in which the level of a signal changes once every predetermined time and a second value in which the signal level changes twice every predetermined time.
In a card reader device which is recorded as value data on a card and reproduces the binary data of the card to determine the first and second values, when the card is inserted, the signal of the signal is transmitted from the inserted card. The time values for each change point are sequentially read, a central value of all the read time values is determined, and a magnitude relationship with respect to the central value is determined for all the time values, and the first and the second values are determined according to the determined magnitude relationship. A read data determination method, wherein one of the second values is determined.