JP7425652B2 - Writing device, writing method, and program - Google Patents

Description

The present invention relates to a writing device, a writing method, and a program.

2. Description of the Related Art Magnetic recording media having magnetic stripes are used in transportation tickets, toll road tickets, and the like. For example, a toll road ticket is issued with entrance information indicating the time and location (entrance toll gate) of entry to the toll road written therein by a toll ticket processing machine installed at an entrance toll gate. In addition, on toll road tickets, entrance information is read by a ticket processing machine installed at the exit toll gate, and exit information indicating the time and location of exit from the toll road (exit toll gate) is written. will be collected.

Such a ticket processing machine has a reader/writer for reading and writing to the magnetic stripe. In the ticket processing machine at the exit toll gate, when the ticket is inserted, the reader/writer pulls the ticket into the back of the ticket processing machine and reads data in the forward direction from the beginning of the magnetic stripe on the ticket. read out. A "preamble" for reading the bit period width indicating the recording density of the magnetic stripe (for example, 100 bpi, 200 bpi, etc.) and a "start" indicating the start position of the data are recorded on the magnetic stripe in order from the beginning. There is.

The reader/writer can correctly read the entry information recorded in the data section after the "start" by reading data at the bit period read from the width of the data recorded as the "preamble". Further, in the ticket processing machine at the entrance tollgate, the reader/writer can confirm that nothing is recorded in the data section (the ticket is a new ticket).

Furthermore, the reader/writer writes entrance information or exit information into the data section of the magnetic stripe at a predetermined bit period while drawing the pass in the forward direction.

After writing the entrance information or the exit information, the reader/writer may read the written information and verify whether the information was written correctly. At this time, the reader/writer reads the magnetic stripe in the reverse direction from the rear end while conveying (ejecting) the drawn ticket to the insertion slot side of the ticket processing machine. In order to make it possible to read the magnetic stripe from the opposite direction, the trailing edge of the magnetic stripe has an "end" mark indicating the end position of the data, and a "post" mark for reading the width of the bit period, similar to the preamble. "amble" may be recorded (for example, see Patent Document 1).

Japanese Patent Application Publication No. 10-326324

However, there are various types of reader/writers used in pass processing machines and the like, and some models do not record "postambles." For example, if the ticket processing machine at the entrance tollgate has such a reader/writer, the "postamble" will be recorded at the rear end of the magnetic stripe for the ticket issued by this ticket processing machine. Not done. If the magnetic stripe is read in the opposite direction when verifying writing in the ticket processing machine at the exit toll gate, the data may not be read correctly.

The present disclosure has been made in view of such problems, and even in a magnetic recording medium without a postamble, it is possible to check whether writing is performed normally while conveying the magnetic recording medium in the opposite direction after writing. Provided are a writing device, a writing method, and a program that can read data correctly during verification.

In order to solve the above problems, the present invention employs the following means.
According to one aspect of the present disclosure, a magnetic recording medium writing device includes a holding circuit that outputs one of binary holding voltages according to an induced voltage generated during transportation of the magnetic recording medium; a write processing unit that magnetizes a recording medium to write data; and a setting unit that sets the output of the holding circuit according to the last polarity written by the write processing unit after completion of writing to the magnetic recording medium. and a read processing unit that reads the written data while transporting the magnetic recording medium in the opposite direction after setting the output of the holding circuit.

According to one aspect of the present disclosure, a method for writing to a magnetic recording medium includes the steps of: outputting one of two binary holding voltages from a holding circuit according to an induced voltage generated during transport of the magnetic recording medium; magnetizing the magnetic recording medium and writing data; setting the output of the holding circuit according to the last polarity of writing after completion of writing to the magnetic recording medium; and setting the output of the holding circuit. Thereafter, the method further includes the step of reading the written data while conveying the magnetic recording medium in the opposite direction.

According to one aspect of the present disclosure, the program causes a computer of a writing device that has a holding circuit that outputs one of two binary holding voltages in accordance with an induced voltage generated during conveyance of a magnetic recording medium to send the magnetic recording medium to the computer. a step of magnetizing a recording medium and writing data; a step of setting an output of the holding circuit according to the last polarity of writing after completion of writing to the magnetic recording medium; and a step of setting the output of the holding circuit after setting the output of the holding circuit. reading the written data while conveying the magnetic recording medium in the opposite direction.

According to at least one aspect of the present disclosure, even if the postamble is not recorded on the magnetic recording medium, when the magnetic recording medium after data is written is conveyed in the reverse direction to verify whether writing has been performed normally. data can be read correctly.

FIG. 1 is a diagram showing a functional configuration of a writing device according to an embodiment of the present disclosure. FIG. 3 is a diagram for explaining the function of a holding circuit according to an embodiment of the present disclosure. 1 is a diagram illustrating an example of a data structure of a magnetic recording medium according to an embodiment of the present disclosure. FIG. 3 is a diagram for explaining functions of a read processing unit according to an embodiment of the present disclosure. 2 is a flowchart illustrating an example of processing of a writing device according to an embodiment of the present disclosure. FIG. 3 is a diagram illustrating an example of a write waveform and a read waveform according to an embodiment of the present disclosure. FIG. 1 is a diagram illustrating an example of a hardware configuration of a writing device according to an embodiment of the present disclosure.

Hereinafter, a writing device, a writing method, and a program according to an embodiment of the present disclosure will be described with reference to the drawings.

(overall structure)
FIG. 1 is a diagram showing a functional configuration of a writing device according to an embodiment of the present disclosure.
As shown in FIG. 1, the writing device 20 of this embodiment is provided, for example, in a housing 10 of a toll road ticket processing machine 1. The pass ticket processing machine 1 has a conveyance path 12 extending from the front side (+Y side) to the back side (-Y side) of the housing 10, and passes the pass ticket T in the forward direction (-Y direction) or Data is read and written on the magnetic stripe M of the pass T while being transported in the opposite direction (+Y direction).

The toll ticket processing machine 1 is, for example, a toll ticket issuing machine that issues toll tickets T to vehicles using the toll road at an entrance toll gate of a toll road. When a vehicle arrives at the entrance toll gate, the ticket processing machine 1 supplies a new ticket T to the conveyance path 12 from a supply section (not shown) inside the housing 10. Then, the writing device 20 of the ticket processing machine 1 writes entrance information including the time and point (entrance toll gate) when the vehicle entered the toll road onto the magnetic stripe M of the ticket T. It is discharged from the discharge port 11A.

The ticket processing machine 1 may be, for example, an automatic toll collection machine (not shown) operated by a passenger of a vehicle or a toll collection machine (not shown) operated by a collector at an exit toll gate of a toll road. It is a pass ticket processing machine that is either built-in or externally attached. When a vehicle arrives at the exit toll gate, the ticket T is inserted through the insertion slot 11B of the ticket processing machine 1 and is transported inside the transport path 12 toward the back side (-Y side). Then, the writing device 20 of the ticket processing machine 1 reads the entrance information from the magnetic stripe M of the ticket T, and also writes the exit information including the time and point (exit toll gate) of the user's exit to the magnetic stripe M. The ticket T is recorded and collected in a collection box (not shown) in the housing 10.

Note that in this embodiment, the pass T is one aspect of a magnetic recording medium. In other embodiments, the magnetic recording medium may be, for example, a transportation ticket, a prepaid card, a point card, or the like.

(Functional configuration of writing device)
The writing device 20 includes a CPU 21 , a read magnetic head 22 , a write magnetic head 23 , a holding circuit 24 , a correction circuit 25 , and a transport mechanism 26 . In this embodiment, the writing device 20 includes one read magnetic head 22 and one write magnetic head 23.

The read magnetic head 22 detects the induced voltage generated by the polar pattern written on the magnetic stripe M when the pass T is conveyed along the conveyance path 12, and outputs it to the holding circuit 24.

The write magnetic head 23 is provided on the deeper side (-Y side) of the transport path 12 than the read magnetic head 22, and records data by magnetizing the magnetic stripe M of the pass T based on a command from the CPU 21. .

The holding circuit 24 outputs one of the binary holding voltages to the CPU 21 according to the induced voltage detected by the read magnetic head 22 .

FIG. 2 is a diagram for explaining the function of a holding circuit according to an embodiment of the present disclosure.
As shown in FIG. 2A, the voltage detected by the read magnetic head 22 is first amplified by the holding circuit 24. As shown in FIG. Next, as shown in FIG. 2(b), the holding circuit 24 sets the output to "HIGH" when the amplified voltage exceeds the first threshold value +X, and thereafter sets the output to "HIGH". keep it as it is. Further, the holding circuit 24 sets the output to "LOW" when the amplified voltage becomes equal to or less than the second threshold value -X, and thereafter holds the output as "LOW". The holding circuit 24 shapes the voltage detected by the read magnetic head 22 into a binarized waveform as described above, and outputs the binarized waveform to the CPU 21 .

Based on a command from the CPU 21, the correction circuit 25 inverts the last polarity written by the write magnetic head 23 and outputs it to the holding circuit 24.

The conveyance mechanism 26 conveys the pass T to the back side (-Y side) or the front side (+Y side) of the conveyance path 12. The conveyance mechanism 26 includes a conveyance roller 260, a conveyance belt 261, and a motor 262. The motor 262 rotates based on instructions from the CPU 21. Then, the rotational driving force of the motor 262 is transmitted to the conveyance roller 260, and the contact surface of the conveyance belt 261 with the pass ticket T is moved to the back side or the front side of the conveyance path 12. Thereby, the conveyance mechanism 26 conveys the pass T to the back side or the front side of the conveyance path 12.

The CPU 21 is a processor that realizes the functions of the writing device 20 by operating according to a predetermined processor. The CPU 21 includes a read processing section 210, a write processing section 211, a setting section 212, and a transport control section 213 as functional sections of the writing device 20.

The read processing unit 210 acquires the data written on the magnetic stripe M of the pass T based on the holding voltage output from the holding circuit 24. Further, the read processing unit 210 reads the data written on the magnetic stripe M while conveying the pass T in the reverse direction (+Y direction) after the setting unit 212 (described later) sets the output of the holding circuit 24.

FIG. 3 is a diagram illustrating an example of a data structure of a magnetic recording medium according to an embodiment of the present disclosure.
As shown in FIG. 3, the magnetic stripe M of the pass T includes "preamble", "start", "data", and "end" in order from the beginning (-Y side) in the longitudinal direction (±Y direction). is recorded. The preamble is information for reading the width of the bit period (for example, 100 bpi or 200 bpi) of the written data, and for example, a fixed value "0000" is recorded. Start and end are information indicating the start position and end position of data, and for example, a fixed value "1111" is recorded. In the data, various information such as entrance information and exit information is recorded in a binarized manner (as a value of "1" or "0") at a predetermined position.

FIG. 4 is a diagram for explaining the functions of the read processing unit according to an embodiment of the present disclosure.
For example, as shown in FIG. 4, it is assumed that information is recorded on the magnetic stripe M using the FM (Frequency Modulation) method in which "1" and "0" are recorded at different frequencies. The read processing unit 210 reads data (“1” or “0”) recorded on the magnetic stripe M based on the read waveform (waveform after amplification and shaping) output from the holding circuit 24. Note that the recording method on the magnetic stripe M is not limited to the FM method, but may also be an MFM (Modified Frequency Modulation) method, an NRZ (Non-Return-to-Zero) method, or the like.

The write processing unit 211 records data on the magnetic stripe M of the pass T through the write magnetic head 23. Specifically, the write processing unit 211 magnetizes the write magnetic head 23 by changing the direction of the signal current flowing through the coil of the write magnetic head 23 according to the data to be written. Then, the polarity indicated by "HIGH" or "LOW" (or "N pole" or "S pole") is written into the adjacent magnetic stripe M bit by bit by the magnetic field generated by the write magnetic head 23. Depending on the frequency of this polarity reversal, a binary value (“1” or “0”) as shown in FIG. 4 can be expressed. Note that the write processing unit 211 writes data at a preset bit cycle or at a bit cycle read by the read processing unit 210.

After the writing to the pass T is completed, the setting unit 212 sets the output of the holding circuit 24 according to the last polarity written by the writing processing unit 211. Specifically, the setting unit 212 inputs the value indicating the last polarity written by the write processing unit 211 to the correction circuit 25. Then, the output of the holding circuit 24 at the start of the next readout is corrected by the correction circuit 25 to one in which the last polarity is inverted.

The transport control unit 213 controls the operation of the transport mechanism 26. When recording entrance information on a new ticket T, or when a ticket T with entrance information recorded is inserted into the insertion slot 11B, the transport control unit 213 instructs the transport mechanism 26 to insert the ticket T. A command to transport in the forward direction (-Y direction in FIG. 1) is output. Further, when the write processing unit 211 completes writing the data, the conveyance control unit 213 outputs a command to convey the pass T in the opposite direction (+Y direction in FIG. 1).

(Processing flow of writing device)
FIG. 5 is a flowchart illustrating an example of processing of a writing device according to an embodiment of the present disclosure.
Hereinafter, an example of the processing of the writing device 20 according to the present embodiment will be described in detail with reference to FIG. 5. Here, an example will be described in which the writing device 20 of the ticket processing machine 1 provided at the exit toll gate reads entrance information and writes exit information.

When the pass T is inserted into the insertion slot 11B of the pass processing machine 1, the conveyance control unit 213 of the writing device 20 moves the pass T in the forward direction (-Y side in FIG. 1) as shown in FIG. The transport mechanism 26 is controlled to transport (step S01).

Next, the read processing unit 210 reads data (entrance information) from the magnetic stripe M of the pass T in the forward direction (step S02).

FIG. 6 is a diagram illustrating an example of a write waveform and a read waveform according to an embodiment of the present disclosure.
In FIG. 6, (a) is an example of a write waveform of data written by the write processing unit 211, (b) is an example of a read waveform of data read by the read processing unit 210, and (c) is an example of a read waveform in the prior art. A comparative example is shown.
The data recorded on the magnetic stripe M is input to the CPU 21 (read processing section 210) through the read magnetic head 22 and the holding circuit 24 as a read waveform shown in FIG. 6(b). The read processing unit 210 reads data (“1” or “0”) based on this read waveform. Further, when the read processing unit 210 completes data reading to the rear end of the magnetic stripe M (+Y side end in FIG. 3), the holding circuit 24 stores the last read data as shown in FIG. The polarity of the read data (last read polarity P1) remains retained. Note that in the example of FIG. 6(b), the final read polarity P1 is "HIGH".

Next, the write processing unit 211 writes new data (exit information) to the magnetic stripe M (step S03).

When the write processing unit 211 completes data writing, the conveyance control unit 213 stops conveyance of the pass T (step S04).

Further, the setting unit 212 obtains the last polarity written by the write processing unit 211 (last write polarity P2) and the bit period (step S05).

Next, the setting unit 212 corrects the output of the holding circuit 24 based on the last write polarity P2 (step S06). As described above, the last read polarity P1 read through the read magnetic head 22 is still held in the holding circuit 24. The setting unit 212 inputs a value indicating the last write polarity P2 to the correction circuit 25. Then, the correction circuit 25 inverts the last write polarity P2 and outputs it to the holding circuit 24. In the example of FIG. 6B, the last write polarity P2 is "HIGH", so the correction circuit 25 causes the holding circuit 24 to output "LOW".

When the setting by the setting unit 212 is completed, the transport control unit 213 controls the transport mechanism 26 to transport the pass T in the opposite direction (+Y side in FIG. 1) (step S07).

Next, the read processing unit 210 reads data in the reverse direction from the magnetic stripe M of the pass T in order to verify whether the data (exit information) has been written correctly (step S08). At this time, the read processing unit 210 reads data based on the bit period acquired by the setting unit 212 in step S05.

For example, in the conventional technique, as shown in FIG. 6C, reading in the reverse direction is started while the last read polarity P1 is held in the holding circuit. Then, as in the example in FIG. 6(c), if the last read polarity P1 and the last write polarity P2 match, the read processing unit detects the start edge of the first bit at the rear end of the magnetic stripe. Therefore, it is difficult to correctly read the first half bit during backward reading.

On the other hand, as shown in FIG. 6(b), the holding circuit 24 according to the present embodiment has the last write polarity ("HIGH") reversed ("LOW") by the setting unit 212 and the correction circuit 25. ) is set to output. Therefore, the read processing unit 210 can detect the start edge of the first bit at the rear end of the magnetic stripe M, so that data can be read normally even when reading in the reverse direction.

Note that the CPU 21 collects the pass T in a collection box (not shown) after confirming whether data has been properly recorded on the magnetic stripe M based on the data read by the read processing unit 210.

The writing device 20 of the ticket processing machine 1 executes the series of processes shown in FIG. 5 every time a ticket T is inserted.

Further, the writing device 20 similarly executes the series of processes shown in FIG. 5 even when the ticket processing machine 1 is a ticket issuing machine installed at an entrance toll gate. At this time, the conveyance control unit 213 conveys the pass ticket T supplied from the supply unit (not shown) to the back side of the conveyance path 12 (step S01). Further, when the read processing unit 210 reads data from the magnetic stripe M of the pass T (step S02) and confirms that the pass T is a new ticket, the write processing unit 211 reads data from the magnetic stripe M of the pass T. Data (entrance information) is written (step S03). Further, when data is read in the reverse direction from the magnetic stripe M by the read processing unit 210 (step S08), the CPU 21 checks whether data is normally recorded on the magnetic stripe M based on the read data. , the ticket T is discharged from the discharge port 11A. Other processing is the same as that of the writing device 20 at the exit tollgate.

(Hardware configuration of writing device)
FIG. 7 is a diagram illustrating an example of the hardware configuration of a writing device according to an embodiment of the present disclosure.
The hardware configuration of the writing device 20 according to this embodiment will be described below with reference to FIG. 7.

The computer 900 includes a processor 901, a main storage device 902, an auxiliary storage device 903, and an interface 904.

The above-described writing device 20 is installed in a computer 900. The operations of each functional unit described above are stored in the auxiliary storage device 903 in the form of a program. The processor 901 reads the program from the auxiliary storage device 903, expands it to the main storage device 902, and executes the above processing according to the program. Further, the processor 901 reserves storage areas corresponding to each of the above-mentioned storage units in the main storage device 902 according to the program. Examples of the processor 901 include a CPU (Central Processing Unit), a GPU (Graphic Processing Unit), a microprocessor, and the like.

The program may be for implementing part of the functions that the computer 900 performs. For example, the program may function in combination with another program already stored in the auxiliary storage device 903 or with another program installed in another device. Note that in other embodiments, the computer 900 may include a custom LSI (Large Scale Integrated Circuit) such as a PLD (Programmable Logic Device) in addition to or in place of the above configuration. Examples of PLDs include PAL (Programmable Array Logic), GAL (Generic Array Logic), CPLD (Complex Programmable Logic Device), and FPGA (Field Programmable Gate Array). In this case, part or all of the functions realized by the processor 901 may be realized by the integrated circuit. Such an integrated circuit is also included as an example of a processor.

Examples of the auxiliary storage device 903 include HDD (Hard Disk Drive), SSD (Solid State Drive), magnetic disk, magneto-optical disk, CD-ROM (Compact Disc Read Only Memory), and DVD-ROM (Digital Versatile Disc Read Only). Memory), semiconductor memory, etc. Auxiliary storage device 903 may be an internal medium directly connected to the bus of computer 900, or may be an external storage device 910 connected to computer 900 via interface 904 or a communication line. Furthermore, when this program is distributed to the computer 900 via a communication line, the computer 900 that received the distribution may develop the program in the main storage device 902 and execute the above processing. In at least one embodiment, secondary storage 903 is a non-transitory tangible storage medium.

Further, the program may be for realizing part of the functions described above. Furthermore, the program may be a so-called difference file (difference program) that implements the above-described functions in combination with other programs already stored in the auxiliary storage device 903.

(effect)
As described above, in the writing device 20 according to this embodiment, the setting unit 212 sets the output of the holding circuit 24 according to the last writing polarity P2. By doing so, the writing device 20 can write data while transporting the ticket T in the opposite direction (+Y direction in FIG. 1) after data has been written, even if the postamble is not recorded on the ticket T. Data can be read correctly when verifying whether the data has been correctly executed. As a result, existing ticket processing machines that cannot record postambles can be continued to be used, so it is possible to suppress an increase in equipment installation costs at tollgates.

Further, the setting unit 212 inputs the last write polarity P2 to the correction circuit 25, and the correction circuit 25 causes the holding circuit 24 to invert and output the last write polarity P2. By doing so, when the read processing unit 210 reads the magnetic stripe M of the ticket T in the reverse direction, it is possible to correctly read data from the first bit at the rear end of the magnetic stripe M.

Further, the setting unit 212 obtains the bit cycle of the data written by the write processing unit 211, and the read processing unit 210 reads the data based on this bit cycle. By doing so, the read processing unit 210 can correctly read the data written on the magnetic stripe M.

Furthermore, the writing device 20 according to the present embodiment has only one reading magnetic head 22, and when verifying written data, the writing device 20 has only one reading magnetic head 22. Read data while By doing so, the writing device 20 does not need to add a read magnetic head for verifying written data on the back side of the write magnetic head 23 (-Y side in FIG. 1). As a result, the manufacturing cost of the writing device 20 can be reduced, and the writing device 20 can be prevented from increasing in size.

Although the first embodiment has been described above in detail with reference to the drawings, the specific configuration is not limited to that described above, and various design changes can be made. That is, in other embodiments, the order of the above-described processes may be changed as appropriate. Also, some of the processes may be executed in parallel.

For example, in the above embodiment, the writing device 20 is provided in the ticket processing machine 1, but the writing device 20 is not limited to this. In other embodiments, the writing device 20 is provided in the transportation It may also be provided within the ticket issuing machine. Further, the writing device 20 may be installed in a processing device for prepaid cards, point cards, etc. installed in a retail store or the like. In this case, the magnetic recording medium is, for example, a transportation ticket, a prepaid card, a point card, or the like.

(Additional note)
The writing device 20, the writing method, and the program of the writing device 20 described in the above-described embodiment can be understood, for example, as follows.

According to a first aspect of the present disclosure, a magnetic recording medium writing device (20) includes a holding circuit that outputs one of binary holding voltages according to an induced voltage generated during conveyance of the magnetic recording medium. (24), a write processing unit (211) that magnetizes the magnetic recording medium and writes data, and after completion of writing to the magnetic recording medium, depending on the last polarity written by the write processing unit, a setting unit (212) that sets the output of the holding circuit; and a read processing unit (212) that reads the written data while conveying the magnetic recording medium in the opposite direction after setting the output of the holding circuit (24). 210).

By doing so, the writing device (20) can transport the magnetic recording medium in the opposite direction (+Y direction in FIG. 1) after writing data, even if the postamble is not recorded on the magnetic recording medium. Data can be read correctly when verifying whether writing has been performed normally.

According to a second aspect of the present disclosure, the writing device (20) according to the first aspect further includes a correction circuit (25) that corrects the output of the holding circuit (24), and the setting section (212) ) inputs the last written polarity to the correction circuit (25), and the correction circuit (25) inverts the input polarity and outputs it to the holding circuit (24).

By doing so, when the read processing unit (210) reads the magnetic recording medium in the reverse direction, it is possible to correctly read data from the first bit at the rear end of the magnetic recording medium.

According to a third aspect of the present disclosure, in the writing device (20) according to the first or second aspect, the setting unit (212) further acquires a bit period of data written to the magnetic recording medium. , the read processing unit (210) reads the data based on the bit period.

By doing so, the read processing unit (210) can correctly read data written on the magnetic recording medium.

According to a fourth aspect of the present disclosure, a method for writing on a magnetic recording medium includes the step of outputting one of two binary holding voltages from a holding circuit according to an induced voltage generated during conveyance of the magnetic recording medium. , a step of magnetizing the magnetic recording medium and writing data; a step of setting an output of the holding circuit according to the last polarity of writing after completion of writing to the magnetic recording medium; and an output of the holding circuit. After setting, the method includes the step of reading the written data while conveying the magnetic recording medium in the opposite direction.

According to the fifth aspect of the present disclosure, the program includes a writing device (20) having a holding circuit (24) that outputs one of two holding voltages according to an induced voltage generated during conveyance of a magnetic recording medium. ) of magnetizing the magnetic recording medium and writing data into the computer (900); and after completing writing to the magnetic recording medium, setting the output of the holding circuit according to the last polarity of writing. and, after setting the output of the holding circuit, reading the written data while transporting the magnetic recording medium in the opposite direction.

1 Passport processing machine 10 Housing 11A Discharge port 11B Insertion port 12 Conveyance path 20 Writing device 21 CPU
210 Read processing section 211 Write processing section 212 Setting section 213 Conveyance control section 22 Read magnetic head 23 Write magnetic head 24 Holding circuit 25 Correction circuit 26 Conveyance mechanism 260 Conveyance roller 261 Conveyance belt 262 Motor T Pass (magnetic recording medium)

Claims (5)

A writing device for a magnetic recording medium,
a holding circuit that outputs one of two holding voltages according to an induced voltage generated during conveyance of the magnetic recording medium;
a write processing unit that magnetizes the magnetic recording medium and writes data;
a setting unit that sets the output of the holding circuit according to the last polarity written by the write processing unit after completion of writing to the magnetic recording medium;
a read processing unit that reads the written data while conveying the magnetic recording medium in the opposite direction after setting the output of the holding circuit;
A writing device comprising: further comprising a correction circuit that corrects the output of the holding circuit,
The setting section inputs the last written polarity to the correction circuit,
The correction circuit inverts the input polarity and outputs it to the holding circuit.
The writing device according to claim 1. The setting unit further obtains a bit period of data written to the magnetic recording medium,
The read processing unit reads the data based on the bit period.
The writing device according to claim 1 or 2. A method for writing on a magnetic recording medium, the method comprising:
outputting one of two binary holding voltages from a holding circuit according to an induced voltage generated during conveyance of the magnetic recording medium;
magnetizing the magnetic recording medium to write data;
After completing writing to the magnetic recording medium, setting the output of the holding circuit according to the last polarity of writing;
After setting the output of the holding circuit, reading the written data while conveying the magnetic recording medium in the opposite direction;
A writing method with A computer of a writing device has a holding circuit that outputs one of two holding voltages depending on the induced voltage generated during conveyance of the magnetic recording medium.
magnetizing the magnetic recording medium to write data;
After completing writing to the magnetic recording medium, setting the output of the holding circuit according to the last polarity of writing;
After setting the output of the holding circuit, reading the written data while conveying the magnetic recording medium in the opposite direction;
A program to run.

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