JPH0352182A - Recording and reproducing device - Google Patents

Abstract

PURPOSE:To easily confirm recorded contents by providing a storing means for information showing a block where recording is performed just before and reproducing the signal recorded just before the first by referring to the storing means at the time of switching a mode from a recording mode to a reproducing mode. CONSTITUTION:The number of a track which is accessed at present is stored in a RAM 70 connected to a slave control circuit 46 as the number of the track to which recording is performed last. When the mode is switched from the recording mode to the reproducing mode, a host control circuit 42 rotates a magnetic disk 10 and makes a mute circuit 36 in a mute state. The circuit 46 transmits mode information, the number of the present track, information of a track table and the number of the track to which recording is performed last to the circuit 42, which sets the number of the present track as the variable of a memory and compares the number of the present track with the number of the track to which recording is performed last. When the control of track-up or track-down is performed and a magnetic head 12 moves to the target track to which recording is performed last, a reproducing action is started so as to reproduce the image recorded just before the first.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a recording and reproducing device, and relates to a recording and reproducing device used, for example, in an electronic still camera.

[Prior Art] Conventionally, the Still Video Conference has defined a format for recording one field of video signals on each of 50 concentric tracks of a magnetic disk. Used as an image recording medium for cameras.

In conventional electronic still cameras equipped with a playback function, the outermost track of the still video floppy is always played back when switching from recording mode to playback mode.

[Problems to be Solved by the Invention] However, in such a configuration, if you want to play back and observe the photographed image after playing it back in the recording mode (that is, recording it to a floppy disk), you can change the recording mode to playback mode. After switching to the mode and setting the magnetic head to the first track,
It is necessary to move the magnetic head to the most recently recorded track by operating the up switch and down switch, which is extremely difficult to operate.

Therefore, an object of the present invention is to provide a recording and reproducing apparatus that can quickly reproduce the immediately previous recorded image.

[Means to solve the problem]

A recording/reproducing apparatus according to the present invention is a recording/reproducing apparatus for a recording medium having a plurality of sections for signal recording, and includes a storage means for storing information indicating the section in which recording was performed immediately before, and a recording mode. The present invention is characterized by comprising a control means that refers to the storage means and reproduces the signal of the section in which recording was performed immediately before, in response to switching to the reproduction mode.

[Function] By providing the above storage means, when the recording mode is switched to the reproduction mode, the most recently recorded signal is reproduced first. Therefore, the recorded contents can be checked extremely easily.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a block diagram of an embodiment of the present invention when applied to an electronic still camera. 10 is a magnetic disk having 50 tracks numbered from 1 to 50 in order from the outermost circumference, 12 is a magnetic head for recording and reproducing, 14 is a motor for rotating the magnetic disk 10, and 16 is a motor 1.
A servo circuit 18 controls the rotation speed of 4 to a predetermined value; 18 moves the magnetic head 12 in the radial direction of the magnetic disk 10;
a head moving mechanism to be positioned on a designated track; 20 a step motor providing driving force for the head moving mechanism;
22 is an innermost circumference detection switch that is turned on when the magnetic head 12 is located on the innermost track; 24 is a magnetic disk 1;
This is a disk detection switch that detects when 0 is set.

26 is an imaging circuit that converts the optical image produced by the optical system 27 into an electrical signal; 28 is an imaging circuit that performs recording signal processing such as gamma correction and FM modulation on the output signal of the imaging circuit 26 to make it suitable for recording on the magnetic disk 10; A recording signal processing circuit 30 converts the signal into a recording amplifier. 31 is a changeover switch that connects to the A contact during playback and the C contact during recording; the B contact indicates that it is not connected to either the A or C contact. Further, 32 is a reproduction amplifier, 34 is a reproduction signal processing circuit that performs reproduction signal processing such as FM demodulation on the output of the reproduction amplifier 32 and outputs a video signal, and 36 mutes the output of the reproduction signal processing circuit 34 in accordance with an external control signal. This is a mute circuit. 38 is a detection circuit for envelope detection of the output of the regenerative amplifier 32, and 40 is a comparison circuit for comparing the output voltage of the detection circuit 38 with a predetermined reference voltage.

42 is a main control circuit that controls each part mentioned above, and 44 is a memory (RAM) that stores variables necessary for the main control circuit 42.
It is. Further, 46 is a sub-control circuit that monitors switch inputs, which will be described later, and performs two-way communication with the main control circuit 42 by handshaking. 48, 50, and 52 are mode setting switches for setting each mode of recording, playback, and lock, 54 is a switch for instructing the start of interval playback, 56 is a switch for instructing track down, and 58 is a switch for instructing track up. switch to indicate,
60 is a switch for instructing execution of a recording operation, and 62 is a switch for instructing preparation for a recording operation.

Note that the mode setting switches 48, 50, and 52 are configured so that only one of them is turned on. Further, the sub control circuit 46 transmits this information to the main control circuit 42 only once when the switch 5456.58 changes from off to on.

64 is a power supply, 66 is a sub control circuit 46 or main control circuit 42
70 is a memory (RAM) that stores data necessary for the sub-control circuit 46. Sub-control circuit 64, OR circuit 6
6 and memory 70 are constantly supplied with power from a power supply 64, and power is supplied to the main control circuit 42 and other circuits via a switch 68. When the output of the OR circuit 66 is high (H), the switch 68 is closed, and when the output is low (L), it is opened. When the sub-control circuit 46 detects that the magnetic disk 10 is set in the recording or reproduction mode, or when the mode is switched from the recording mode to the reproduction mode or vice versa, the reproduction mode is set by the mode setting switch 50. When the recording switch 60 or the recording preparation switch 62 is turned on in the recording mode, the signal 66b is set high. When the main control circuit 42 is supplied with power, it first sets the signal 66a high to communicate with the sub-control circuit 46, and during the communication, the sub-control circuit 46 sets the signal 66b high.

The operation when loading the magnetic disk 10 will be explained with reference to FIG. The sub-control circuit 46 is constantly supplied with power supply voltage from the power supply 64, and detects the setting of the magnetic disk 10 by the disk detection switch 24. magnetic disk 10
When detecting the setting of , the sub control circuit 46 checks the mode setting switches 48 , 50 , 52 , and if the mode setting switches 48 , 50 , 52 are not locked, closes the switch 68 via the OR circuit 66 and supplies power to the main control circuit 42 and other circuits. Ensure voltage is supplied.

When the main M# circuit 42 is applied with the power supply voltage, it connects the switch 31 to the b contact, puts the mute circuit 36 into the mute state, and makes the signal 66a high.

Next, the sub control circuit 46 sends an initialization command to the main control circuit 42 (Sl), and also sends the mode setting switch 48,
50. Send recording or playback depending on the status of 52. Such an initialization command is issued when the magnetic disk 10 is newly set, or when the initialization command is sent once the magnetic disk 10 is set, but when the power supply 64 is replaced or the like, the main control circuit 42 is Sent when power supply is cut off once. The main control circuit 42 rotates the magnetic disk 10 via the servo circuit 16 and the motor 14, and moves the magnetic head 12 toward the inner circumference one track at a time until the innermost circumference detection switch 22 is turned on (S2
．． 3). Next, the track number 50 is set in the memory variable T of the RAM 44, the track table is initialized to "0" as shown in FIG. 3, and the switch 31 is connected to the a contact point (S4). In the track table of this embodiment, 7 bytes of addresses a to g are used, and 1 bit is assigned to each track. The same table is also prepared in the RAM 70 for backup purposes.

The reproduction output of the magnetic head 12 is applied to the detection circuit 88 via the switch 31 and the reproduction amplifier 32, envelope detection is performed, and the comparison circuit 40 compares the detection output with a reference voltage level. This makes it possible to determine the presence or absence of a recording signal. If there is a recorded signal, the tiger. A recorded flag is set at the bit position of track T in the track table, and if there is no recording signal, the recorded flag is reset (S5, 6).
．． 7). Then, the main control circuit 42 transmits information on the recorded flag of the track T to the sub control circuit 46, and the sub control circuit 46 stores this in the track table of the RAM 70 (S8).

If the track being accessed, that is, track T, has not been recorded (S9), or if it has been recorded but is not in recording mode (S10), until it becomes the first track (S11)
, down one track at a time to check whether each track is to be examined (S12.5-10). If track T has already been recorded and is in recording mode (89.10), if track T is not the 50th track, it will move up one track (S
13.14), at the 50th track, magnetic head 1
2 at that position (S13), the main control circuit 42 sends an initialization end command to the sub control circuit 16 (S15). In the recording mode (S16), the main control circuit 42 also sets the signal 66a to low and closes the switch 68 (Sl7).
, if it is not the recording mode, the mute of the mute circuit 36 is released (S4g).

When the magnetic disk 10 is set in the single-recording mode by the above operation, it is checked in order from the innermost track to the outer circumferential direction, and an empty track one innermost from the recorded track is checked. Position the magnetic head to complete the initialization. Further, if all the tracks are unrecorded, the initialization is completed at the first track, and when the innermost track (50th track) has been recorded, the initialization is completed at the 50th track.

Note that when a magnetic disk is set in the playback mode, it is checked in order from the 50th track to the 1st track whether or not recording has been completed, and the initialization ends at the 1st track.

The sub control circuit 46 is stored in the RAM 70, and the main control circuit 42 is stored in S8.
The track number T transmitted from the track number T is set as To, and the recorded flag is stored at the corresponding location in the track table.

After the initialization in the recording mode is completed, the switch 68 is turned off, power supply to the main control circuit 42 and other circuits is cut off, and only the sub control circuit 46 is operating. Therefore, the track table stored in the RAM 44 and the number T of the track being accessed are lost, but the same data is stored in the RAM 70.

The operation when the recording preparation switch 62 is turned on with only the sub-control circuit 46 operating after initialization and in the recording mode will be described with reference to FIG. When the recording preparation switch 62 is turned on, the sub control circuit 46 outputs the signal 66.
b goes high, turns on the l switch 68, and turns on the main control circuit 4.
Make sure that power is supplied to 2. The main control circuit 42 makes the signal 66a high, keeps the switch 68 on, rotates the magnetic disk 10, and connects the switch 31 to the b contact. The sub control circuit 46 sends mode information (recording) to the main control circuit 42 (S20) and the current track number TO
(S21), track table information (S22) is transmitted. The main control circuit 42 sets the current track number TO received from the sub control circuit 46 in the memory variable T (S
23), set variable T in memory variable T1 (S24)
).

The main control circuit 42 refers to the bit content of the track T1 in the track table and determines whether it has been recorded ("1") or not (S25). If recorded, find an unrecorded track in the track table (S25).
), or until the 50th track (S26), the variable T
Increment 1 (S27). If the 50th track is filled with recorded tracks (S26),
It is determined that there are no empty tracks, and the sub-control circuit 46 is notified of this fact (S28), the signal 66a is set low, the switch 68 is turned off (S35), and the process ends.

If track T1 is not recorded in the track table, that is, if its bit content is “O” (S25),
The track T1 that has been confirmed to be unrecorded is compared with the current track T (S29), and if they are not equal, the magnetic head 12 is tracked up until they become equal, that is, T is incremented (S30). If T1 and T are equal (S29), the recording switch 60 is checked (S31), and if it is on, the imaging circuit 26 is driven, the switch 31 is connected to the C contact, and the photographed field video signal is transferred to the magnetic disk 10. (S33), the main control circuit 42 sets the corresponding bit in the track table to "1", and sends the current track number T and information that the track has been recorded to the sub control circuit 46. Send (S34).

The sub control circuit 46 stores the received track number T in the RAM 70.
The fact that it has been recorded again is stored as T2. Thereafter, the process returns to S24, and an empty track is searched for by the routines 825-27.

If the recording switch 60 is not on (S31), if it is in the recording mode (S32), wait for the recording switch 60 to be turned on, if it is not in the recording mode (S32), turn off the switch 68 (S35), finish.

FIG. 5 shows a detailed flowchart of the track-up control in S30. If the current track is the 50th track on the innermost track (S40), return as is,
If it is not the 50th track (S40), the magnetic head 12
is moved to the inner circumference by one track (S41), and the variable T is set to 1.
(S42), checks whether or not the track T has been recorded using the track table, and sends the information and the contents of the variable T to the sub-control circuit 46 (S43).

In the manner described above, video signals are recorded while searching for empty tracks up to the 50th track.

In the RAM 70 connected to the sub-control circuit 46, the currently accessed track number T is stored as the track number T2 on which recording was last performed.

Next, the operation in the reproduction mode will be explained with reference to FIG.

For example, assume that the mode changes from recording mode to playback mode. The sub-control circuit 46 sets the signal 66b high to turn on the switch 68 so that power is supplied to the main control circuit 42. The main control circuit 42 sets the signal 66a high, holds the switch 68 in the on state, rotates the magnetic disk 10, connects the switch 31 to the b contact, and mutes the mute circuit 3
6 is muted. The sub-control circuit 46 provides the main control circuit 42 with mode information (playback) (850), current track number TO (S51), and track table information (
S52) and track number T 2 (S53).

The main control circuit 42 sets the current track number TO received from the sub control circuit 46 in the memory variable T (S54), and compares the current track number T with the track number T2 (S54).
55), perform track-up control or track-down control so that T=72 (S56, 57.58)
.

When the magnetic head 12 moves to the target track T2, a reproducing operation is started (S59). Specifically, switch 31
is connected to the a contact, and the reproduction output of the magnetic head 12 is transmitted to the reproduction signal processing circuit 34 via the switch 31 and the reproduction amplifier 32.
The signal is supplied to the playback signal processing circuit 34 and subjected to playback processing such as demodulation to obtain a playback video signal. Then, when the main control circuit 42 releases the mute of the mute circuit 36 (S60), the reproduced video signal is output.

Thereafter, the main control circuit 42 learns the status of each switch through communication with the sub control circuit 46, and while in the playback mode (S65
), perform the corresponding actions.

That is, track-up control is performed in response to the up switch 58 (S61.67), and track-down control is performed in response to the down switch 50 (S62.68).

When the playback mode switch 50 is turned off (S65),
The main control circuit 42 uses the signal 66a as the input switch 68.
(S66), and the sub control circuit 46 stores the current track number T as T2 in the RAM 70 (S69).

That is, when proceeding to 866 in playback mode, in the RAM 70,
The variable that currently holds the track number and T2 have the same contents.

In recording mode, as shown in Figure 4, after recording,
The magnetic head is moved to an unrecorded track on the inner circumferential side. Even if there are some recorded tracks on the inner circumferential side, the movement is made so as to avoid such recorded tracks and detect unrecorded tracks. Therefore, when switching from the recording mode to the reproduction mode, the track on which the magnetic head is positioned is not the track on which recording was performed immediately before.

In this embodiment, the number of the track on which recording was performed immediately before is stored as T2, and the magnetic head is moved to track T2 from 355 to 58, so that the image recorded immediately before is reproduced first. This operation is the same even if there is a recorded track on the way.

Note that in this embodiment, the lock mode is an operation mode in which the various states of the recording mode or playback mode before entering the lock mode are maintained as they are, and the mode change from recording mode to lock mode toge playback mode is as follows: This is equivalent to a mode change from recording mode to playback mode.

FIG. 7 shows a detailed flowchart of track down control (S58). If the current track T is the first track (S80), return as is; if not, move the magnetic head 12 by one track to the outer circumferential side (S81), and subtract 1 from the variable T (S82). ), T
is greater than or equal to the TO received in S51 (S83)
, if T is not greater than or equal to O, set T to the variable To (S
84), connect the switch 31 to the a contact point, perform RF detection, and check whether recording has been completed (S85). As a result of S84, the variable To always holds the lowest track number that has been played since the start of playback.

When T is greater than or equal to TO (S83) and RF detection (S85)
After that, the track number T and information as to whether or not it has been recorded are transmitted to the sub-control circuit 46 (S86).

When switching from the reproduction mode to the recording mode, the sub-control circuit 46 may set the variable T2 in the RAM 70 to 1. In this way, the magnetic head 12 accesses the first track when returning to the playback mode without performing any recording.

Although we took a magnetic disk as an example of a recording medium, it is not limited to this, but can also include magnetic tape, optical disks, magneto-optical disks, etc.
Furthermore, it may be a solid state memory device such as a semiconductor memory.

[Effects of the Invention] As can be easily understood from the above explanation, according to the present invention, no matter which section was accessed for recording, when switching from recording mode to playback mode, the immediately previous recorded The recorded images are played back first, making checking the recorded images much easier.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the configuration of an embodiment of the present invention, Fig. 2 is a flowchart of initialization, Fig. 3 is a memory layout diagram of the track information table, Fig. 4 is a flowchart of the recording mode, and Fig. 5 is a flowchart of the track information table. FIG. 6 is a flowchart of up control, FIG. 6 is a flowchart of playback mode, and FIG. 7 is a flowchart of trackdown control. 42: Main control circuit 44, TO+RAM 46: Sub control circuit 48, 50, 52: Mode setting switch 54
: Interval playback start switch 56: Down switch 58: Up switch 60: Record switch 62: Record preparation switch

Claims (1)

[Claims] A recording/reproducing apparatus for a recording medium comprising a plurality of sections for signal recording, comprising: a storage means for storing information indicating the section in which recording was performed immediately; and upon switching from recording mode to playback mode, 1. A recording and reproducing apparatus comprising: a control means for reproducing a signal of a section in which recording was performed immediately before by referring to the storage means.