DE3612815A1 - INFORMATION RECORDING PROCEDURE - Google Patents

Description

Information recording method

The invention relates to a recording method, in the one in a device that allows information to be transmitted under linear relative reciprocation between the recording and reproducing apparatus and a Recording media are recorded and played back, a check is made as to whether information has been recorded correctly.

Recently, information has been transmitted in an optical or magnetic manner with relative linear back and forth Moving one, hereinafter referred to as a recording head Writing unit of the recording and reproducing device in relation to a card-shaped recording medium recorded. In this case it is important to quickly check after a write whether the information recorded correctly or without errors have been.

1 illustrates a procedure for determining whether the

-4- DE 5771

Information has been recorded correctly or not. With 1 is an information track on a record carrier denotes on which the information is to be recorded, with 2 the direction is a Relative movement of a recording head with respect to the recording medium shown during a writing process and at 3 is the direction of relative movement of the recording head with respect to the recording medium

, q in a period between the writing process and a Information reading process for checking the recorded information. When the recording head is moved in the direction of 3, no writing operation and no reading operation are carried out. The head movement during

,, _ this period of time is known as idling. Numeral 4 is the direction of relative movement of the recording head in relation to the recording medium when checking the recorded information, while at 5 the direction of relative movement of the recording head with respect to the recording medium when returning the recording head to an initial position in preparation for the next writing process. In the write process in which such a Record testing method used is for recording information on an individual Information track a two-time relative movement between the recording head and the recording medium required, during the two-time reciprocating movement, the idling movement is brought about twice.

_ As a result, the times for recording and that Read long for the exam.

The invention is based on the object of an information recording method to provide information recorded on a recording material ι

whose exam is read and in which, despite reading, j

-5- DE 5771

the total time required for recording is short for the test.

In the information recording method of the present invention information is recorded on a recording medium during a forward movement with a recording head recorded, after which during a return movement those recorded during the forward movement , Q information in the opposite order to the recording order Sequence can be read and determined from the information read during the return movement whether or not the information has been recorded correctly or without errors.

When in the information recording method of the present invention the information recording medium consists of a material that cannot be rewritten and is determined it has been found that an information track contains incorrectly recorded information can be stored on the recording medium.

ger an indicator mark can be recorded, which indicates that the track erroneously recorded information and should not be reproduced during playback. The indicator marker can point to

._ an extension line of the track on the recording 25

carrier are recorded. By recording a Such an indicator mark is immediately detected during the playback process that the track has not been read should be or is not readable.

In the information recording method of the present invention the check as to whether the information has been recorded correctly or not can be carried out in various ways Procedures are made. In a first method, the data to be recorded and that of the

Record track read data bit by bit with each other

-6- DE 5771

compared. A second method uses an error detection code like a cyclic redundancy check (CRC) check code added to the end of the data to be recorded and recorded together with these on the recording medium, after which an error from the reproduced data and the error detection code is determined. In detail, one is the one to be recorded Data and an error detection code containing data .Q value U (x) selected so that it is always by a polynomial expansion G (x) is divisible without a remainder. If there is no recording error, the record carrier reproduced data value U (x) can be divided by the expansion polynomial G (x) without a remainder, but then, p. if an error occurs during the recording, one of data value U '(x) reproduced on the recording medium is not divisible by G (x) without a remainder. In this way, any occurring during the recording can be Errors are detected. In a third method, an error correction code such as a Reed-Solomon code is used

data to be recorded and together with them recorded, after which, when checking, an error according to the read data and the error correction code is corrected and an error detection is switched on for the display whether the correction has been made 25th

has been or not. If an error occurs during recording that cannot be corrected, the Error detection indicates that the correction has not been made, so that a faulty recording is made is shown. In the following description of an

The first method is described as an example.

The invention is explained in more detail below on the basis of exemplary embodiments with reference to the drawing.
35

-7- DE 5771

Fig. 1 illustrates an information recording method According to the state of the art.

Fig. 2 illustrates an embodiment of the invention Information recording procedure .

Fig. 3 shows an embodiment of a device, Q for optical information recording and reproduction for the information recording method of the present invention.

FIGS. 4A, 4B and 4C illustrate a further embodiment. Example of the information recording method of the present invention.

2 illustrates a method according to the invention in accordance with an exemplary embodiment. 1 is an in _n formation track referred to as 6, the direction of relative movement of a recording head is shown in relation to a recording medium during a recording operation, and is illustrated with 7, the direction of relative movement of the recording head with respect to __ the recording medium during a testing procedure. Since the test operation or test read operation is carried out immediately after the recording operation, as shown in Fig. 2, a signal is read out on a time axis opposite to the time axis in the recording operation, the recording and the test being carried out with one reciprocating movement of the recording head. As a result, the time for idling the head is saved, so that the times for recording and checking can be shortened.

The signal read out during the test process has the for

-8- DE 5771

Order of the during the recording process signal applied to the recording head in opposite order. As a result is

κ it is useful when comparing the playback signal with the recording signal during the test process Signals from a storage device in the order of the signals used in the recording process read out in the opposite order.

In general, it is expedient to check the signal from the information track of the recording medium during the test process read out in such a way that the reproduced signal can be used unchanged. If the signal from the Storage device is read out and recorded in opposite order on the time axis, can the signal read during the test can be used without reversing the sequence.

FIG. 3 shows an exemplary embodiment for a device for the optical recording and reproduction of information according to the method according to the invention. the Fig. 3 shows a central processing unit (CPU) 11 which performs all functions of the recording and reproducing apparatus

controls a card-25, hereinafter referred to as a card

shaped recording medium 12 for optical recording, an optical head 13 which carries light beams for the optical recording and reproduction of information A drive device 14 is directed at the card 12

for moving a slide 30 (not shown) back and forth

be unit on which the card 12 is placed, in the direction of an arrow A or B, a main memory 15 such as a personal computer that stores the information to be recorded on the card 12 and a

addressable or retrieval memory 16. in which an information 35

mation track line of recording signals is stored

-9- DE 5771

can be. The ones stored in the retrieval memory 16

Signals can be read out either in the forward direction or in the opposite direction. At 17 a Verc denotes the same circuit.

For a recording operation, a single information track line of the recording signals is sent to the retrieval memory 16 in response to a command from the central processing unit 11. _n sent and stored in this. A single line of the recording signals is then read out of the retrieval memory 16 in the opposite direction by means of a signal from the central unit 11. In this way, the signal, which is reversed with regard to the time axis, is sent to the

,,. see head 13 created in order to have an intensity module 15

tion of a semiconductor laser light source (not shown) of the optical head 13 to make. In synchronism with this, the driver circuit for the drive device 14 is activated a signal from the central unit 11 put into operation in such a way that by means of the modulated light beams from the optical head 13, the information is recorded on an information track of the card 12 while this is offset in the direction of arrow A. At the end of the recording process, a signal

from the central unit 11 via the driver circuit through 25

the drive device 14 opposed to the card 12 moved in the direction of arrow B. Simultaneously with this, the optical head 13 reproduces the information that while moving forward on the recording track have been recorded, and the reproduced signal is output to the comparison circuit 17. Synchronous with this a signal from the central unit 11 is applied to the retrieval memory 16 in such a way that a track or Line of the recording signals stored in this memory are read out in the forward direction and sent to the Ver-35

equalization circuit 17 is applied. That from the on-demand memory

-10- DE 5771

rather 16 read out signal and that with the optical head 13 read signals are compared by the comparison circuit 17 with each other. If the information is correct or have been recorded without errors, a signal is sent to the central unit 11 from the comparison circuit 17 Signal applied in such a way that by an instruction from the central processing unit 11 the recording signals in the polling memory 16 are deleted and this by a signal fed from the central unit 11 to the main memory 15 a new single line of recording signals is supplied and is saved. When the comparison circuit 17 detects that the information is not correct have been recorded, the comparison switch

. The device 17 sends a corresponding signal to the central unit 11, in response to which the recording and checking are repeated.

The relative speed between the optical head _13n and the card 12 is higher in the checking operation than in the recording operation because the light intensity of the optical head 13 in the checking operation may be lower than that in the recording operation. In this way, the light intensity of the optical head 13 for the inspection process is selected to be lower than that in the recording process.

In the recording operation to the optical head 13 to be applied recording signals and the test process recording signals to be applied to the comparison circuit 17 can be generated by means of program equipment or by means of circuit equipment will.

The optical head 13 of Fig. 3 may be any of various known devices such as those for

-11- DE 5771

be optical recording disks or compact disks, so its detailed description is omitted here.

Figures 4A, 4B and 4C illustrate another

Embodiment of the information recording method according to the invention. In this embodiment, by means of two separate light beams at the same time q ₁ the information of two adjacent information tracks reproduced.

4A shows information tracks 21, 22, 23 and 24, Recording paths 21-0, 22-0, 23-0 and 24-0, return paths

, c 21-1 and 23-1 to return after recording, test paths 21-2, 22-2, 23-2 and 24-2 and arrows each showing the direction of relative movement of a head on a recording material Show. Illustrative are the recording paths, the return paths, and the test paths

2Q is shown separately, but they actually run on a line, namely on an information track. At the end of return path 21-1 for a previous lane the head on the information track 21 is moved in the opposite direction on the recording path 21-0, with

rtc input information on the information track 21 in reverse Order to be recorded. At the end of the recording on the information track 21 is again the Head movement direction reversed so that the recorded information is checked on the test path 21-2 and

_on then the head is moved to the information track 22.

Thereafter, the original Information is recorded on the information track 22 in reverse order. At the end of the recording process the direction of head movement is reversed. On the test path 22-2, at the end of the test process, the

-12- DE 5771

Head to the information track 23 shifted.

The subsequent processes are odd numbered tracks are identical to track 21, while the even-numbered tracks are identical to track 22 are. The return path is provided in the odd-numbered tracks, whereas in the even-numbered tracks Tracks no return route is required. At jQ all information tracks is the relative speed between the head and the card in the checking process is substantially the same as that in the reproducing process.

Fig. 4B shows the order of the information recorded on the information tracks. The order of the information recorded on the information tracks 21 to 24 is denoted by 21-3, 22-3, 23-3 and 24-3, respectively. The successions are opposite to the directions of the recording paths 21-0 to 24-0 and have the same direction as the test paths 21-2 to 24-2. As a result, some of the processing of the reproduced in the testing procedure signal special treatment erforder ^Lich ·

4C illustrates the simultaneous reading of two tracks. With 21-4, 22-4, 23-4 and 24-4 are respectively the directions of the paths for the playback from the infor _n mationsspuren 21, 22, 23 illustrated and 24 respectively. In the reproduction, the information tracks 21 and 22 and the information tracks 25 and 24 are respectively reproduced as a pair. 4C, the directions 21-4 to 24-4 of the reproduction paths in the respective tracks correspond to the orders of the information recorded on the information tracks. As a result, the return

-13- DE 5771

The transfer process does not require any special processing.

In this embodiment, the return route occurs which no information is processed, only once for every two tracks. That way you can opposite the above-described embodiment, the total test time can be shortened.

jQ If the relative speed between the head and the Recording medium in the checking process is the same as that in the recording process, a circuit for the reproduction of the information can be used together.

In the embodiment shown in Fig. 4, two tracks are read simultaneously while the sequence the information is reversed for every two tracks. The greater the number of tracks read at the same time

_9C) , the fewer the number of idle movements and the more the total time for recording and checking is shortened. If η tracks are read at the same time and the order of the information is reversed for each η tracks, the idle movement occurs once

_p. each η traces on.

An information recording method is specified, in which during a forward movement by means of a recording head Information on a recording medium recorded during a return movement the information recorded during the forward movement in the opposite order to the recording order Sequence can be read and determined from the information read during the return movement

whether the information was recorded correctly ο

who are or are not.

Claims (7)

TlEDTKE - BüHLING - KmMN-E - ßfiUPE ΕΚΚΐΚ Ep! Pellmann - Grams - Struif S-chem'c Dipl.-Ing. R. Kinne #j Cj <* * y pt 4 c Dipl.-lng. R group OO I L α Γ ü Dipl.-lng. B. Pellmann Dipl.-Ing. K. Grams Dipl.-Chern. Dr. B. Struif Bavariaring 4, P.O. Box, ~; 4 8000 Munich 2 Tel .: 089-539653 Telex: 5-24845 tipat Telecopier: 0 89-53737? cable: Germaniapsient Munich April 16, 1986 DE 5771 Claims 1 . A method for recording information on a recording medium by relative reciprocation between a recording head and the recording medium, characterized in that * movement at a Vorlaufbe- information by means of the recording head to \ the recording medium are recorded, that, in a return movement in the forward movement recorded information are read in the opposite order to the recording order and that, based on the information read, it is checked whether the information has been recorded correctly. 2. The method according to claim 1, characterized in that if an incorrect recording of the information is determined, an indicator mark on the recording medium to indicate the faulty recording is recorded. 3. The method according to claim 1 or 2, characterized in that when checking the information to be recorded and the read information is compared bit by bit with one another in order to check whether the information is present have been recorded without errors. 4. The method according to claim 1 or 2, characterized in that the information to be recorded is an error detection code is added and that when checking g it is determined based on the error detection code whether an error occurred during the recording process. 5. The method according to claim 1 or 2, characterized in that the information to be recorded is an error correction code it is added that by means of the information recorded during the forward movement and the Error correction codes an error is corrected and that an error identifier is set to indicate whether the correction has been made or not. 6. Method of recording information on a optical card with relative reciprocation between an optical head and the optical card, thereby characterized in that on a forward movement the optical card using light beams from the opti-20 see head information that is recorded at a backward movement recorded during the forward movement Information in the recording order are read in the opposite order, with the Relative speed between the optical card and 25 the light beams in reading is higher than the relative speed between the optical card and the light beams in recording, and that it is checked based on the information read whether the information has been recorded correctly.
30th 7. The method according to claim 6, characterized in that during the recording, the order of the information recorded on the tracks relating to the direction of the relative movement between the optical head and the optical card is opposite.