JPH04134730A - Information recording and reproducing device - Google Patents

Abstract

PURPOSE:To rapidly cope with such a situation as when a characteristic of a medium, etc., is changed by making the contents of a storage means stored with a characteristic data of a pickup of its own selectively rewritable from the outside by a rewrite means of a host computer, etc. CONSTITUTION:A read signal obtained from the pickup 1 is processed by a signal processing circuit 4 and afterward binarized at a binarization threshold level by a comparator 6 to be outputted as a binarized read signal S, and this is transferred as a read data after processing to a host computer 7. Then, a binarization threshold level of a D/A converter 5 is set via a controller 3 based on the characteristic data of the pickup 1 of its own stored in a E<2>PROM 2, while the contents of the E<2>PROM 2 are changed via the controller 3 by the host computer 7. By this method, when the characteristic data stored in the storage means is required to be rewritten, the rewrite is easily and rapidly performed without detaching the pickup from the device.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention uses a pickup to record and/or record information.
Or it relates to an information recording and reproducing device that performs reproduction.

[Conventional technology]

As information recording and reproducing devices using pickups, magnetic disk devices, optical disk devices, optical card devices, and the like are known. In these devices, the pickup is generally treated as a unit, and each unit is replaced during repair.

Furthermore, these pickups usually have manufacturing variations, so in order to absorb these variations, adjustment mechanisms are provided in the mechanical parts and signal processing circuits.

For example, in a signal processing circuit, a semi-fixed resistor is provided in the circuit, and this is adjusted to match the characteristics of the pickup.

However, in devices with a semi-fixed resistor in the signal processing circuit, if the pickup is replaced, the value of the semi-fixed resistor in the signal processing circuit must also be changed accordingly, so it is not possible to replace the pickup as a complete unit. The problem is that it cannot be treated as

In order to solve such problems, the applicant, in Japanese Patent Application No. 1-257792, stores characteristic data unique to the big amplifier in a memory circuit inside the big amplifier.
An information recording and reproducing apparatus has already been proposed in which the characteristics of a control circuit that controls the operation of the pickup are automatically changed based on the characteristic data. In this information recording and reproducing device, for example, characteristic data of the tracking servo circuit is written in an E2FROM provided in the pickup, and by controlling an electronic volume provided in the adjustment circuit, the characteristics of the trunking servo circuit can be kept constant. I try to do that. Furthermore, it can be applied not only to the characteristics of the tracking servo circuit, but also to the setting of the optimal power value of a laser diode (LD) when writing to a medium, and the binarization thread and shoulder level value of a read circuit.

[Problem to be solved by the invention]

However, it has been found that the above-mentioned information recording and reproducing apparatus previously proposed by the applicant has some points to be improved as described below.

That is, the characteristic data stored in the memory circuit can be read or written only when the pickup unit is manufactured, and cannot be read or written while the pickup unit is installed in the device. For this reason, especially when the write sensitivity of the recording medium changes significantly or the reflectance of the recording medium changes, the pickup must be removed from the device and the data in E"FROM must be rewritten, making it difficult to perform a rewrite operation. The problem is that it is very troublesome and time consuming.

The present invention has been made in view of these problems, and provides an information recording and reproducing device appropriately configured to easily change the characteristic data of a pink amplifier even when a big amplifier is incorporated in the device. The purpose is to

[Means to solve the problem]

In order to achieve the above object, the present invention provides an information recording and reproducing apparatus that records and/or reproduces information on an information recording medium using a pink amplifier, which is provided in the pickup and stores characteristic data specific to the pickup. means, adjustment means for automatically setting operating characteristics for the pink-up based on the characteristic data stored in the storage means, and means for selectively rewriting the characteristic data stored in the storage means. will be established.

[For production]

According to this configuration, when it is necessary to rewrite the characteristic data stored in the storage means, the rewriting can be easily and quickly done without removing the pickup from the device by issuing a command from the rewriting means such as a host computer. It becomes possible to do so. Furthermore, if the device has already been shipped to the user's site, it is possible to rewrite the program easily and quickly by supplying a program that runs on a host computer, for example, on a floppy disk or the like.

〔Example〕

FIG. 1 is a block diagram showing a first embodiment of the invention. In this embodiment, in an optical card recording and reproducing apparatus, the threshold level for binarizing a read signal from an optical card is changed by an external command. This optical card recording and reproducing device includes a pickup 1 for recording and reproducing information on an optical card (not shown), and a pickup 1 provided on the pickup 1, and 2 pickups.

E”FROM 2 that stores characteristic data specific to 1;
Controller 3 that controls the operation of the optical card recording and reproducing device
, a signal processing circuit 4 that processes the read signal from the pickup 1, and a signal processing circuit 4 that processes the read signal from the pickup 1, and
A D/A converter 5 that sets the a threshold level, and a pickup 1 processed by a signal processing circuit 4.
A comparator 6 binarizes a read signal from the D/^ converter 5 using the output, and a host computer 7 that communicates with the controller 3 to control the operation of the optical card recording/reproducing device.

Note that the E2FROM 2 and the D/8 converter 5 do not require fast access times, so in order to reduce the number of signal lines with the controller 3, it is preferable to use elements that can exchange data serially. Furthermore, a one-chip microcomputer is used for the controller 3 in order to reduce the number of signal lines to be controlled.

In the above configuration, the read signal obtained from the pinkup 1 is processed by the signal processing circuit 4, and then binarized by the comparator 6 at a binarization threshold level set in advance by the D/A converter 5, It is output as a binary read signal.

This binary read signal is processed by a data processing circuit (not shown) and then transferred to the host computer 7 as read data.

In this embodiment, the controller 3
The binarization threshold level of the D/A converter 5 is set via the controller 3, and the contents of the E2FROM 2 are changed by the host computer 7 via the controller 3.

Figure 2 A and B are from the host computer 7 to the E2F
This shows an example of a command between the host computer 7 and the controller 3 when accessing the contents of ROM 2. FIG. 2A shows the command when reading data from E''FROM 2, and FIG. The commands used to write data to E2FROM 2 are shown below. These commands are compliant with 5C5I, which is a standard interface between a personal computer and an external storage device.
r tlnique).

FIG. 3 shows an example of the storage contents of the E2FROM 2, and in this case, an E2FROM with a capacity of 96 bytes is used. Therefore, the commands shown in FIGS. 2A and 2B read or write all 96 bytes. In FIG. 3, address O is a checksum byte of all data, which is used to check for garbled internal data.

FIG. 4 shows an operation flowchart of the host computer 7 when rewriting part of the data in the E"FROM 2. First, using the E2FROM 2 read command, all the data in the E2FROM 2 is written to the host computer 7. The data is read into the RAM inside the computer 7.

At this time, a sum check is performed using the check sum byte at address 0, and it is confirmed that the data can be read normally.

Here, if it cannot be read normally, retry the specified number of times, and if an error still occurs, the E2FROM
2 is considered an error.

If all the data in E2FROM 2 can be read normally, the address to be changed, in this example, the host computer corresponds to address 04H of the data to be set in the D/A converter 5 that determines the binarization threshold level. Rewrite the data in RAM in 7 to the desired value.

After that, calculate the thumb check for all 96 heights,
RA corresponding to address O? Write checksum byte to address 1.

Next, transfer all data (96 heights) in the RAM to the E2F.
Controller 3 using ROM 2 write command
Transfer to and write. Finally, another E2PR
E2FROM 2 using OM 2 read command
The writing is confirmed by reading out all the data in the data and comparing it with the previously read data. Note that the rewritten data and the thumb check height are not compared with the previously read data, but are compared with the data to be rewritten and the newly calculated thumb check height.

When the controller 3 receives the write command for the E2FROM 2, it changes the binarization threshold level of the D/A converter 5 corresponding to the rewritten data to a set value.

In this way, according to this embodiment, the data in the E"FROM 2 can be changed only by commands from the host computer 7, so characteristic data unique to the pickup 1 can be changed much more easily and quickly than in the past. Can be changed.

FIG. 5 is a block diagram showing a second embodiment of the invention. This embodiment is an optical card recording/reproducing apparatus in which the output power of an LD (not shown) is changed by a command from a host computer 7 when information is written to an optical card. That is, based on the characteristic data (LD power during writing) specific to the pickup 1 stored in the E2FROM 2, the D/D is transmitted via the controller 3.
The output of the A converter 5 is set, and the LD drive circuit 8 controls the current flowing through the LD based on the output of the D/A converter 5 to set the output power of the LD to the optimum value stored in the E2FROM 2. This E"FROM
In this embodiment, the write LD power stored in the host computer 7 is changed via the controller 3 by the host computer 7 in the same manner as in the first embodiment. The write LD power stored in the E2FROM 2 is changed by changing the contents of the data address 03H in the E''P)IOM 2 shown in FIG. 3.

In each of the embodiments described above, the checksum calculation and NU2 of the data in the E2FROM 2 are performed on the host computer 7 side, but these may be performed on the controller 3 side, or if an error occurs during communication. Both parties may take this into account.

[Effects of the Invention] As described above, according to the present invention, the contents of the storage means storing the unique characteristic data of the pink-up can be selectively rewritten from the outside by a rewriting means such as a host computer. Even if the characteristics of the medium etc. change, it can be easily and quickly dealt with without removing the pick amplifier from the information recording/reproducing apparatus and readjusting it.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention, FIGS. 2A and B are diagrams showing an example of commands for accessing the contents of the E2FROM shown in FIG. 1, and FIG. 3 is a block diagram showing the same < E2FROM FIG. 4 is a flowchart showing an operation when rewriting a part of data in the E2FROM, and FIG. 5 is a block diagram showing a second embodiment of the present invention. 1...Pickup 2...E2FROM3
...Controller 4...Signal processing circuit 5.
・・D/A converter 6・Comparator 7・
...Host computer 8...LD drive circuit Fig. 2 Fig. 1

Claims (1)

[Scope of Claims] 1. An information recording and reproducing apparatus that records and/or reproduces information on an information recording medium using a pickup, comprising: a storage means provided in the pickup and storing characteristic data unique to the pickup; The method further comprises: an adjustment means for automatically setting operating characteristics for the pickup based on characteristic data stored in the storage means; and a means for selectively rewriting the characteristic data stored in the storage means. Information recording and reproducing device featuring features.