JPH01211371A - Readout timing controlling circuit - Google Patents

Abstract

PURPOSE:To increase the operating speed of a readout timing controlling circuit by using a readout select instruction and the stop instruction of the operation of a readout/write circuit after they are once combined at a transient time when readout is performed. CONSTITUTION:When the write mode is switched to the readout mode, the write instruction from a control processing section 11 is switched to a readout instruction. Upon switching, a readout/write selection controlling section 4 shifts a readout/write circuit 2 from a writing state to a readout state and, at the same time, sends the operation stop signal of the circuit 2 to a readout/write circuit operation controlling section 5 from the control processing section 11 by a fixed time T. When a start signal is resent thereafter, a transient signal having the waveform of an output signal is ignored and abrupt rise is suppressed. Therefore, the transient output of an AGC circuit 9, to which readout signals are inputted, is suppressed and the signals can be recognized as readout signals in a short period. Accordingly, the readout signals can be processed quickly.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a magnetic recording device f1. Or it relates to timing control of readout circuits used in other devices.

(Prior Art) Generally, when reading, a read command is transferred from a control processing unit to a read/write control unit of a read/write circuit, but an operation start command of a read/write circuit is read from a control processing unit. /Not transferred to the write circuit operation control section.

The waveforms of each signal shown in FIG. 3 are based on the prior art. In FIG. 3, (a) is a read selection command, (b)
is the output of the read/write circuit, and (C) is the output of the AGC circuit that stabilizes the output gain of the read/write circuit.

When the mode changes from write to read in FIG. 3 and the control processing section sends out the selection command shown in FIG. continues to send out only

(Problems to be Solved by the Invention) In the conventional read timing control circuit described above, a sharp rise occurs in the signal read by the read/write circuit immediately after the write command is transferred to the read command, so that the AGC in the subsequent stage The steep rising waveform in the circuit becomes larger and the transient characteristics of the signal output from the %AGC circuit are emphasized. A read signal containing a steep rising waveform cannot be processed satisfactorily within a transient period, and processing can only be started after a long period of time has elapsed.

It is an object of the present invention to make it possible to start/stop circuit operation by selecting successive or writing when reading/writing information to a magnetic recording device or the like. Provided is a start-up timing control circuit configured to eliminate the above-mentioned drawbacks and speed up the operation by once using a combination of a successive selection command and a stop command for the start/write circuit operation during a transient period. It's about doing.

(Means for Solving the Problems) A read timing control circuit according to the present invention provides read/v!
The device is configured to include a reading section, a read/write selection control section, a read/write circuit operation control section, an AGC circuit, and a control processing section.

The reading/writing section 4 is for reading/writing information to/from a magnetic recording device or the like.

The read/write selection control section is for selecting successive reading/writing sections or writing.

The read/write circuit operation control section is a companion device that starts/stops the circuit operation of the read/write section.

The AGC circuit is for controlling the output width of the readout/input section.

The control processing section is for sending out a starting selection gold alloy to the read/write selection control section in the read mode, and once sending a stop command for the read/write circuit operation to the read/write circuit operation control section during a transient state. be.

(Example) Next, one embodiment of the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of a read timing control circuit according to the present invention. In Figure 1, 1 is a magnetic head, 2 is a read/write circuit, and 3 is a read/write circuit.
4 is a read/write selection control section, 5 is a read/write circuit operation control section, 9 is an AGC circuit, and 11 is a control processing section.

In FIG. 1, a magnetic head 1 reads and writes information on a magnetic medium, and a read/write circuit 2 includes a read/write section 3 for reading and writing information.
Reading or some say writing is a friend's reading/
The read/write circuit operation control section 5 is provided for starting/stopping the read/write circuit operation.

The output of the read/'V# write circuit 2 is connected to the AGC circuit 9, and the read/write selection control section 4 and the read/write circuit operation control section 5 are connected to the control processing section 11.

When switching from the write mode to the read mode to read information existing on the magnetic medium, the write command from the control processing section 11 is switched to a read command. By this switching, the read/write selection control unit 4 changes the state from the write state to the read state, so the read state signal is sent to the signal line 6.
Receive from.

As a result, the 1g output/write circuit 2 shifts from the write state to the read state, and the read/write circuit operation stop signal is sent from the control processing section 11 for a certain period of time T via the signal line 7 to the output/write circuit operation control section. Send to 5.

FIG. 2 is a timing diagram showing the waveforms of each signal on signal lines 6 to 8.10 of the read timing control circuit shown in FIG. 1 according to the present invention.

As shown by signal line 7, once the operation of read/write circuit 2 is stopped, the transient response from AGC circuit 9 onto signal line 10 is significantly suppressed.

(Effects of the Invention) As explained above, the present invention can change the state from the write state to the read state. At the same time as transferring to 4'i, by sending the stop signal to the write/write circuit operation control unit for the stop period and then resending the start signal, the transient response of the output signal shaping can be ignored, and the steep It has the effect of suppressing the rise of beans.

Therefore, when the read signal is input to the AGC circuit, the AG
Since the transient output of the C circuit is suppressed and can be recognized as a read signal in a short period of time, there is an effect that the read signal can be processed quickly.

[Brief explanation of the drawing]

Figure wJ1 is a block diagram of an embodiment of a read timing control circuit according to the present invention. FIG. 2 is an explanatory diagram showing operation waveforms of various parts during timing control according to the present invention. FIG. 3 is an explanatory diagram showing operating waveforms during conventional timing control. DESCRIPTION OF SYMBOLS 1... Magnetic head 2... Read/write circuit 3... Output/@writing section 4... Read/write selection control section 5... Read/write circuit operation control section 9... AGC
Circuit 11...Control processing unit 6-8.10...Signal line Patent applicant NEC Corporation

Claims (1)

[Claims] a read/write section for reading/writing information to a magnetic recording device or the like; a read/write selection control section for selecting reading or writing from the read/write section; and a read/write section for selecting the read/write section. a read/write circuit operation control section for starting/stopping the circuit operation of the read/write circuit, an AGC circuit for controlling the output amplitude of the read/write section, and a read selection command for the read/write selection control section in the read mode. A read timing control circuit comprising: a control processing section for transmitting a command to stop the read/write circuit operation to the read/write circuit operation control section at the time of transition;