JPS61208582A - Card reader - Google Patents

Abstract

PURPOSE:To decode an information except for a damage section by synthesizing proper reading informations of a coming path and a returning path from a front or a rear sections, respectively. CONSTITUTION:A control section 10 normally rotates or reverses a motor 6 through a driving circuit 11 and drives in reciprocation relative to a reading head 9 of a card. By respective reading operations of a coming path and a returning path, a reproducing signal obtained through the reading head 9 and an amplifying circuit 10 is decoded by a decoding circuit 13 and given to the control section 10. When there are damages such as a bending, flaws, the control section 10 synthesizes a reasonable information on the way of the respective reading operations of said reciprocation from a front and a rear sections. The control section operates so as to limit a section incapable of reproducing the information due to the damages to minimum.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a card reader for reading recorded information on various cards.

<Summary of the Invention> In this invention, card information is read back and forth so that even if the edge is bent or scratched, other parts can be properly reproduced. Information is synthesized from the front and the rear, respectively.

<Background of the Invention> Conventionally, in a system using a card that records information using a modulation method that combines a clock and information, such as FM or MFM, if the card is broken or scratched in the middle, There was a drawback that it became impossible to reproduce or decode the information after that part, and depending on the location of the bend or scratch, it became impossible to use the Gustem with that card.

<Purpose of the Invention> This invention makes it possible to decode information other than the damaged part even if a card is damaged such as being bent or scratched, so that the use of the system using the card is not hindered. The purpose is to provide a card reader.

<Structure and Effects of the Invention> In order to achieve the above object, the card reader according to the present invention moves the card back and forth relative to the reading head, and reads the correct information up to the middle obtained in each reading operation on the outward and return paths. It is configured to synthesize from the front and the rear.

According to this invention, since the properly read information for the outbound and return trips is synthesized from the front and back, the portion that cannot be decoded due to damage is minimized, that is, only the damaged portion, and the system using the card is available in many cases.

<Description of Embodiments> FIG. 1 is an explanatory diagram showing an example of a card feeding mechanism of a card reader according to the present invention. This card feeding mechanism is
A pair of loafs 3a3b, 4a, 4b are respectively disposed in the insertion slot 2 of the card 1 and the insertion back direction position, and the upper and lower conveyor belts 5a.

5b is wrapped around it. The lower conveyor belt 1-5a is bidirectionally driven by a motor 6, while the upper conveyor belt 5b is given appropriate tension by the action of rollers 7, and is conveyed while being held between the upper and lower conveyor belts 5a and 5b. The card 1 is pressed by a pressing roller 8 while a magnetic head 9 reads card information.

FIG. 2 is a block diagram showing an embodiment of a card reader according to the present invention. The control unit 10 includes a drive circuit 11
The motor 6 is driven in forward and reverse directions through the drive, and the card 1 is reciprocated relative to the reading head 9. The reading head 9 is
The reproduced signal obtained through the amplifier circuit 12 is decoded by the decoding circuit 13 and provided to the control section 10. If the card has damage such as bending or scratches, the control unit 10 combines the proper information obtained up to the middle of each round-trip reading operation from the front and back, as described below, and collects information on the damage caused by the card. Works to minimize unreproducible parts.

FIG. 3 is a flowchart showing the operation of the control section 10. The control section 10 first waits for the card 1 to be inserted in step 21, and when the card 1 is inserted into the insertion slot 2, the control section 10 proceeds to step 22 and gives a command for normal rotation of the motor 6 to the drive circuit 11. As a result, the motor 6 is driven to rotate in the normal direction, and the card 1 is held by a pair of conveyor bells (5a, 5b) and transferred in the insertion direction (receiving direction), and the card 1 is transferred to the reading head 9.
Information on the outbound route is read by.

The read information is sent to the control unit 10 in step 23.
The information is sequentially stored in a memory (not shown) within the memory. This step 23 continues until the next step 24 determines whether reading is complete or not and becomes "Yes".

If the determination in step 24 is "Yes", then the process proceeds to step 25, where the control section 10 gives a command to reverse the motor 6 to the drive circuit 11. As a result, the motor 6 is driven in the reverse direction, the card 1 is transported in the opposite insertion direction (return direction), and the reading head 9 reads information on the return trip.

The read information is sent to the control unit 10 in step 26.
The information is sequentially stored in the memory (not shown) in the memory. This step 26 continues until the next step 27 determines whether the reading is completed or not. If the determination in step 27 becomes @Yes', step 28
Then, the control unit 10 issues a motor stop command to stop the motor 6. This completes the reading of information from the card 1 on the outbound and return trips.

Subsequently, in step 29 and subsequent steps, the information read as described above is combined. As shown in FIG. 4, the read and decoded information is configured, for example, in units of one byte, and a parity bit P is added as a check bit for checking reproduction errors for each unit. This makes it possible to accurately identify the position of a playback error due to card damage as a parity error. Information after the parity error occurs is discarded as inaccurate information.

Figure 5 (-1 is an explanatory diagram showing card information read from a normal card. This card information consists of N bytes, with each byte as one unit, C, C2, C2,
..., shown as CN.

Each unit C,,C2,...,CN includes a parity pit b+7+b27+...', BN7, respectively.

Here, the case where a parity miss occurs in the M-th (1<M<N) hide CM of FIG. 5 (al) will be described with reference to step 29 and subsequent steps in FIG. 3.

In addition, in the following explanation, each read information of the outbound trip and the return trip is as shown in FIG. 5(b) and FIG. 5 [C1,
Each byte is A1°A2. ...,
AN and B1. B2. ... - Expressed as BN.

First, in step 29, the count n indicating the nth unit is set to n=1, and then in step 30, it is determined whether the A1 data on the outward path is appropriate, that is, whether a parity error has occurred.

When it is appropriate, the process proceeds to step 31, where A1 is adopted as the correct C1 information, and then, in step 32, n is counted up by 1 and n=2.

Next, in step 33, it is determined whether the data has ended, and since the answer is "NO" in this case, the process returns to step 3o, and it is determined whether the A2 data is appropriate.

Repeat the above operations until CM-□-AM-□.
A1~AM-1 data on the outbound trip is 01~CM
, adopted as information.

Since a parity error has occurred in the next AM data, the determination in step 30 is "NO" and the process proceeds to step 34. In step 34, n=N is set, and then in step 35, the BN data on the return trip is correct. Find out whether

If it is correct, the process proceeds to step 36, where this BN data is adopted as the correct CN information, and then, in step 37, n is counted down by 1 to make n=n-1. Next, in step 38, it is determined whether the data is finished, and in this case, the answer is "NO", so the process returns to step 35, and
Determine whether the data is appropriate. The motion τ[CM
Repeat until -1-1= BM-1-+, and convert BN'=8M+1 data on the return trip to the real price CN-0M+
Adopted as 1 data.

Since a parity error occurs in the next BM data, the determination in step 35 is "No" and step 39
Proceed to. In step 39, the normal data adopted as described above is synthesized from the front and back, and as shown in FIG. If the data is combined, even if the card is damaged, it is often only 1 to 2 bytes that become unreadable, and this degree of unreadability often does not cause any problems for the system. Therefore, it is useful.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the card feeding mechanism according to the present invention, and FIG.
FIG. 3 is a block diagram of the card reader according to the present invention, FIG. 3 is a flowchart showing its operation, and FIGS. 4 and 5 are explanatory diagrams showing read data. l...Card 5a, 5b...
Conveyor belt 6...Motor 9...°Pa reading head 10...Control unit

Claims (2)

[Claims] (1) A device in which a card on which information is recorded reciprocates relative to a reading head, and is configured to combine the appropriate information obtained up to the middle of each reading operation on the forward and return trips from the front and back. A card reader characterized by: (2) The information is configured in predetermined bit units,
The card reader according to claim 1, further comprising a check bit for checking reproduction errors for each unit.