JP2545386B2 - Information recording device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording apparatus, and more particularly to an information recording apparatus such as a magnetic disk recording apparatus in which a read check immediately after writing cannot always be expected at the time of writing information. The present invention relates to an information recording apparatus suitable for ensuring that the information being written has been correctly transferred.

[Prior Art] A conventional information recording apparatus is shown in FIG.

In the conventional technique shown in FIG. 2, the information sent from the computer 101 is converted by the control device 102 into a format that can be easily recorded, transferred to the recording device 103, and recorded in a recording medium.

In the control device 102, the line receiver 104 first receives information. The output is input to the error detection / correction code creation circuit 106. The error detection / correction code creation circuit 106 checks whether or not the reproduced information is correct at the time of reproduction, and when it is not correct, creates an error correction code having the ability to correct it. This error correction code is added behind the information sent from the computer 101. The addition of this error correction code is performed by the selection circuit 107. The output of the selection circuit 107 is the parallel-serial converter 109.
Is converted into serial data by the modulation circuit 110 and further converted into code words such as MFM and RLL by the modulation circuit 110, and the transfer line 113 is driven by the line driver 112 and sent to the recording device 103.

In the recording device 103, the transmitted recording information is received by the line receiver 114, transmitted to the driver 116 through the flip-flop 115, and recorded on the recording medium by the head 117.

In the above recorded information transfer system, circuit failure,
Information may not be transferred correctly due to poor contact of the connector or disconnection of the cable. At this time, if it is overlooked that the recorded information is incorrect, a device that performs read-after-write such as a magnetic tape storage device may be used, but a read check immediately after writing, such as a magnetic disk storage device, may be performed. If you don't necessarily expect the device, incorrect files will be created one after another, and if you try to read after the file, you may not be able to read at all, which may lead to a big accident.

In order to avoid this accident, even in the prior art, it is usual to provide an abnormality detection circuit for each functional block.

This will be described with reference to FIG. 2. In the control device 102, the parity abnormality detection circuit 105 for checking the parity of the output of the receiver 104 and the error detection / correction code creation circuit 106.
There is an abnormality detection circuit 108, an abnormality detection circuit 111 for detecting an abnormality of the modulation circuit 110, etc., and the recording current is not flowing in the recording apparatus 103 even though recording is being performed, or the direction of the recording current is not switched. There is an abnormality detection circuit 118 that detects this.

In FIG. 2, reference numeral 119 indicates a recording current flowing through the head.

Next, the operation of the abnormality detection circuit 118 will be described with reference to FIG.

In a normal state, the recording current 119 flowing through the head is always inverted at a certain period as shown in FIG. Therefore, as shown in FIG. 3 (b), when the current does not reverse for a certain period of time, it is determined to be abnormal, and the abnormality detection signal is activated.

A conventional technique related to this type of device is, for example, a technique described in Japanese Patent Application No. 60-189582.

[Problems to be Solved by the Invention] In the related art, the abnormality detection circuits 105 and 10 of the control device 102 are disclosed.
Since the 8111 uses the parity check method, there is a problem that a single-bit error can be detected, but a multi-bit error cannot be detected.

Further, in the abnormality detection circuit 118 of the recording device 103 of the prior art, as described above, data does not come at all for a certain period of time.
In other words, it is usually possible to detect an anomaly only when no data is sent from 1 byte to several bytes.
There was a problem that a drop in the data of a few bits and an abandonment could not be detected. There is a limit in trying to detect this accurately by shortening this time. Especially, when the RLL code which is currently optimized for high recording density is adopted, it is normal data and the data interval is 2 to 8 (1to7 Method), 3 to 8 (2to7
However, it is impossible in principle to perform drop-in and pull-out of several bits of data by the above-mentioned conventional technique.

Further, a failure such as a drop of several bits of data or a side opening may occur due to a contact failure of a connector, an intermittent failure of a line driver and a line receiver, a half disconnection of a transfer line, or the like. Particularly, since the data transfer rate has recently become high, the amplitude of the signal cannot be sufficiently obtained. In addition, in order to strengthen against external noise, it is often transferred in differential mode. In this case, if one line is disconnected,
Since the amplitude margin is lost, the above-mentioned trouble is likely to occur.

Further, the prior art is also ineffective against the intermittent failure of the write information transfer circuit such as the flip-flop in the recording device.

An object of the present invention is to solve the above-mentioned problems of the prior art, and to reduce a single bit of information in a write information transfer system.
An object of the present invention is to provide an information recording device capable of accurately detecting an intermittent abnormality such as a barking.

[Means for Solving Problems] The information recording apparatus of the present invention comprises a control device and a recording device. Of these, the control device receives the write information transmitted from the host device and the first line receiver, and receives the output of the first line receiver to perform error detection / error detection.
An error detection / correction code creation circuit for creating a correction code; a selection circuit for sequentially selecting and outputting the output of the first line receiver and the error detection / correction code output from the error detection / correction code creation circuit; It is configured to include a parallel / serial conversion circuit that performs parallel / serial conversion of the output, a modulation circuit that modulates the output of the parallel / serial conversion circuit, and a line driver that outputs the output of the modulation circuit to the information transfer line. Further, the recording device records on the head by receiving a second line receiver for receiving the write information and the error detection / correction code transferred from the control device through the information transfer line, and an output of the second line receiver. And a driver that outputs a current. Based on the above configuration, the information recording apparatus of the present invention has the following features.

That is, the control device includes a control circuit that outputs a control signal that indicates a period during which a recording current corresponding to write information is output from the driver, and the modulation circuit of the control device includes a recording current output from the driver. A means for outputting a clock signal for demodulating
The recording device receives a recording current output from the driver and the clock signal, demodulates the recording current, receives an output of the demodulation circuit and the control signal, and outputs a recording current corresponding to write information. The demodulation circuit is provided with an error detection / correction code inspection circuit for inspecting the error detection / correction code.

[Operation] When the write information and the error detection / correction code added behind it are input to the error detection / correction code check circuit using the same method as the error detection / correction code creation circuit, EC
With the C method, the result is 0 (zero) when there is no error in the information.
Becomes

According to the present invention, the recording device is provided with an error detection / correction code check circuit, and the write information sent from the control device is subjected to the error detection / correction of the same algorithm as the error detection / correction code creation circuit in the control device. It is input to the code check circuit, and it is determined whether the result becomes 0 or not.

As a result, according to the present invention, it is possible to accurately detect an intermittent abnormality such as a drop or a single bit of write information sent from the control device to the recording device.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

 FIG. 1 is a block diagram showing one embodiment of the present invention.

The information recording apparatus of the embodiment shown in FIG. 1 comprises a control apparatus 1 connected to a computer 101 as a higher-level apparatus and a recording apparatus 2 connected to this.

The control device 1 includes a line receiver 3 and error detection /
Error detection / correction code creation circuit 4 as means for creating a correction code, selection circuit 5, parallel-serial conversion circuit, modulation circuit 7, line driver 8, and control circuit 9
And a parity abnormality detection circuit 20.

The recording device 2 includes a line receiver 10, a flip-flop 11, a driver 12, a head 13, a demodulator 14,
Error detection / error detection as a means of checking the correction code /
It has a correction code checking circuit 15.

The line driver 8 of the control device 1 and the line receiver 10 of the recording device 2 are connected by an information transfer line 16.

Next, the operations of the information recording apparatus and the error detection / correction code inspection circuit 15 of the above embodiment will be described.

The write information sent from the computer 101 as the host device is input to the error detection / correction code creation circuit 4 through the line receiver 3 of the control device 1, and at the same time, to the selection circuit 5.

The selection circuit 5 outputs the write information until the write information sent from the computer 101 is completed,
After the completion, the error detection / correction code generation circuit 4 is controlled to output the error detection / correction code.

The output of the selection circuit 5 is converted into serial data by the parallel-serial conversion circuit 6 of the control device 1, and further encoded by the modulation circuit 7 in a format for recording on a recording medium (not shown).

The signal encoded by the modulation circuit 7 is sent by the line driver 8 to the recording device 2 through the information transfer line 16.

The recording device 2 receives the encoded signal by the line receiver 10, inverts it by the flip-flop 11, and records it on the recording medium by the driver 12.

In this embodiment, since the data modulated by the control device 1 is transferred to the recording device 2, the recording device 2 needs to demodulate. The clock signal 17 for this is supplied to the control device 1
To the recording device 2. Further, a control signal 18 for instructing the recording device 2 of the start and end timings of the write information is also sent from the control device 1 to the recording device 2.

In the recording device 2, a recording current exactly equal to the recording current 13 output from the line driver 12 is input to the demodulation circuit 14. The demodulation circuit 14 demodulates the recording current using the clock signal and transfers the demodulated data to an error detection / correction code check circuit 15 having the same algorithm as the error detection / correction code creation circuit 4 of the control device 1. Enter and control signal 18
The error detection / correction code check circuit 15 is operated while the signal is active. As a result, the error detection / correction code inspection circuit 15 extracts the write information. And
When the control signal 18 drops, the error detection / correction code check circuit 15
Is stopped, and whether the result is 0 or not is determined by the ECC method, and when it is not 0, the abnormality detection signal 19 is raised to notify the computer 101.

In the case of the method of modulating in the recording device 2, since it is not necessary to demodulate again in the recording device 2, the clock signal 17 and the demodulation circuit 14 are unnecessary.

According to this embodiment, the write information sent from the control device 1 has an error detection / correction code having the same algorithm as the error detection / correction code creation circuit 4 in the control device 1 provided in the recording device 2. Since it is inputted to the inspection circuit 15 and it is determined whether or not the result becomes 0, the drop of single bit information in the write information transfer system,
It is possible to detect intermittent abnormalities such as bleeding with high reliability.

According to the present invention described above, the recording device is provided with the error detection / correction code check circuit having the same algorithm as the error detection / correction code creation circuit provided in the control device,
Since the write information sent from the control device is input to the error detection / correction code check circuit and whether the result becomes 0 or not is determined, a single bit in the write information transfer system is used. As a result of being able to accurately detect an intermittent abnormality such as a drop in information or a side effect, even if a failure occurs, there is an effect that it is possible to prevent the trouble of continuing to create an illegal file without noticing it, and eventually the information recording apparatus. There is an effect that the reliability can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a block diagram showing a conventional technique, and FIG. 3 is an operation explanatory diagram of an abnormality detection circuit in a recording apparatus in the conventional technique. 101: Computer as a higher-level device, 1 ... Control device, 2
...... Recording device, 4 …… Error detection / correction code creation circuit, 15
...... Error detection / correction code inspection circuit as means for inspecting error detection / correction code, 16 ...... Information transfer line.

Claims (1)

(57) [Claims] 1. A first line receiver for receiving write information transmitted from a host device, and an error detection / correction code creation circuit for receiving the output of the first line receiver and creating an error detection / correction code. The output of the first line receiver and the error detection / correction detection / correction code output from the code generation circuit
A selection circuit for sequentially selecting and outputting the correction code; a parallel / serial conversion circuit for parallel / serial conversion of the output of the selection circuit;
A control device including a modulation circuit that modulates the output of the serial conversion circuit and a line driver that outputs the output of the modulation circuit to an information transfer line, and write information transferred from the control device through the information transfer line and error detection / An information recording apparatus including a second line receiver for receiving a correction code and a driver for receiving an output of the second line receiver and outputting a recording current to a head, The device includes a control circuit that outputs a control signal indicating a period in which the recording current corresponding to the write information is output from the driver, and the modulation circuit of the control device demodulates the recording current output from the driver. The recording device outputs the clock current and the recording current output from the driver. A demodulation circuit for receiving and demodulating the recording current, and an output of the demodulation circuit and the control signal for receiving the output of the demodulation circuit of the recording current corresponding to the write information and detecting the error detection / correction code An information recording device comprising a correction code checking circuit.