JPH0419811A - Rotary head type magnetic recording/reproducing device - Google Patents

Abstract

PURPOSE:To reduce the tape access frequency in a high speed searching job, etc., by attaching a monitoring rotary head to a rotary head cylinder with a level difference secured to a recording/reproducing rotary head. CONSTITUTION:A monitoring rotary head B' is positioned lower than the recording/reproducing rotary heads B and A by 1.5 times as much as a track pitch Tp. Then a monitoring rotary head A' is positioned lower than the head B' by 2 times as much as the pitch Tp. Thus a pair of heads A' and B' are attached to a rotary head cylinder 1 with the prescribed level differences secured to both heads A and B. Thus two tracks forming a frame can be reproduced in the same order as that of the recording state when a magnetic tape is driven in the direction adverse to the recording direction and at a speed equal to the recording state. As a result, the tape access frequency is reduced in a high speed searching job, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a computer external storage device to which a rotary head type magnetic recording/reproducing device such as R-DAT is applied.

(b) In the conventional R-DAT, a magnetic tape is wound around a rotary head cylinder, and digital data is recorded by forming oblique tracks on the magnetic tape using a rotary head attached to the rotary head cylinder. R-DAT is capable of high-density recording, uses powerful error detection and correction codes, and has high data reliability.Furthermore, high-speed searches are possible using subcodes recorded separately from these data. .

When the above-mentioned R-DAT is used as an external storage device for a computer in the field of information equipment, it is very advantageous in saving space because more than IG bytes of information can be recorded on one tape.

(c) Problems to be Solved by the Invention R-DAT forms tracks on a tape in an inclined manner, and interleaves data within the frame, with two adjacent tracks recorded by rotating heads having different azimuth angles as one frame. is being processed.

When using the R-DAT as a data recorder, one group is made up of multiple frames, and data is recorded and played back in groups. In order to record additional data from the middle of a group recorded on a tape, it is necessary to play back that group, and when the rotating head is positioned behind that group on the tape, the tape is run in the opposite direction. It is most efficient to perform playback with
It is necessary to add a symbol processing circuit for reproducing the tape in the reverse direction. If you do not add that signal processing circuit,
This requires operations such as rewinding, playing, rewinding, and recording the tape, resulting in problems such as inefficiency in terms of time, etc., and an increased burden on software.

(d) Means for Solving the Problems In order to solve the above problems, the present invention forms tracks on a magnetic tape using a rotating head, and combines two adjacent tracks recorded by magnetic heads with different azimuth angles into one track. In a magnetic recording/reproducing device that forms frames and processes recorded/reproduced data on a frame-by-frame basis, during the recording operation, a pair of rotary recording/reproducing heads retrace the recorded tracks to determine the recorded state. A pair of rotating monitor heads are installed to monitor the data, and when the tape is run in the opposite direction and at the same speed as when recording, the two tracks that make up one frame are recorded in the same order as when recording. The present invention proposes a rotary head type magnetic recording/reproducing device, characterized in that the monitor rotary head is attached to a rotary head cylinder with a step provided relative to the recording/reproducing rotary head.

(E) Function: Since the pair of rotary heads for monitoring are attached to the rotary head cylinder with a predetermined difference in level from the rotary heads for recording and reproducing, the magnetic tape can be rotated in the opposite direction to the recording and reproducing heads. When running at the same speed as , the two tracks that make up one frame can be played back in the same order as they were recorded.

(f) Example An example of mounting a rotary head according to the present invention is shown in Fig. 1(a).
, (b) and will be explained below. FIG. 1(a) is a view of the rotary head cylinder (1) seen from above, in which a pair of recording/reproducing rotary heads (A) and (B) having different azimuth angles are spaced at an interval of 80°. In addition, a pair of rotating heads (A') for monitors having different azimuth angles (
B') are also attached to the cylinder (1) at 180° intervals, and the four rotating heads (A) (A') (B
)(B') are spaced at 90° intervals.

The cylinder (1) rotates in the direction of the arrow (X), so the tape is traced in the order of rotating head (A) → rotating head (Bo) → rotating head (B) → rotating head (A゛). Become. The rotating head for monitoring (Bo) is located at a position 1.5 times the track pitch (Tp) lower than the rotating heads for recording/playback (B) and (A), and the rotating head for monitoring (A゛) is Furthermore, it is located at a position lower than the monitoring rotary head (Bo) by twice the track pitch (Tp).

FIG. 2 is a simple block diagram showing the flow of signals during recording and reproduction. During recording, recorded data is interleaved in an interleave circuit (2),
) is written into the RAM (4) by the FCC circuit (5), which generates a parity of C,,C, for the data in the RAM (4), and then reads out the recorded data from the RAM (4). Add a synchronization signal etc. with the signal processing circuit (3),
The signal is amplified by a recording/reproducing amplifier (6) and recorded on a tape by rotating recording/reproducing heads (A) and (B). Furthermore, the data recorded on the tape is monitored by a rotating head (A).
(Bo), amplified by the reproduction amplifier (7), converted into a digital signal by the waveform equalization/PLL circuit (8), extracts the reproduced clock, and processed by the signal processing circuit (9) as a sync signal for tracking. Detection, that is, checking the recorded state, extracts the data, and performs error detection in the ECC circuit (10).

During normal playback, data is reproduced from the magnetic tape using the rotary recording/reproducing heads (A) and (B), amplified by the recording/reproducing amplifier (6), and then converted into a digital signal by the waveform equalization/PLL circuit (11). The reproduced clock is taken out, inputted to the signal processing circuit (3) via the signal selector (12), a sync signal for tracking etc. is detected, only the data is extracted and stored in the RAM (4). The FCC circuit (5) performs error detection on the data, the signal processing circuit (3) reads it from the RAM (4), and the de-interleave circuit (13) returns the data to its original order. Output.

During reverse playback, the data from the tape is played back using the rotating monitor heads (A') and (B'), and the playback amplifier (7)
After amplification, the waveform equalization/PLL circuit (8) converts it into a digital signal, extracts the reproduced clock, passes through the signal selector (5), and inputs it to the signal processing circuit (3), where it is processed in the same way as during normal reproduction. is performed and outputted from the deinterchange circuit (13).

First, during recording, as shown in FIG.
When signals are recorded on the tape in the order of l+k)las*bs, tracks are sequentially formed as shown in FIG. Here, a l! a! l 23 is a signal recorded by the rotary head (A) for recording/reproduction, b
l+b 1+b is the rotary head for recording/playback (B
). Rotating head cylinder (1)
Each head (A) (A') (B) in one rotation of
For example, if the rotary head (A) records a track of signal a, the trace of (B') is traced by the rotary head (Bo).
is 1.5Tp compared to the rotating head (A) as shown in Figure 1.
(1.5 times the track pitch), so signal b before signal a! trace the track. Similarly, after the rotating head (B) records a track of the signal,
Since the rotary head (A') has a step difference of 3.5 Tp from the rotary head (B), the track of the signal a, which is three tracks before the signal b3, is traced.

Therefore, the playback output of the track on which the signal of FIG. 3(a) is recorded is as shown in FIG. 3(a).
b 1b! The order is as follows. Here, C0 and C of the playback data
7 Perform error detection. Furthermore, C1IC! Since the code is completed within each track, this playback output is al+b 1
．． The order does not have to be a l + b y 1)
.

During normal playback, the rotation direction (A) (B) is the same as when recording.
Since the trace is repeated, a as shown in Figure 3 (a)
++ Obtain playback output in bl, al, b- order.

Next, when the tape is run in the opposite direction, there will be a difference between the angle of the track relative to the tape and the angle that the head traces, but in R-DAT, the head width is 1.5 times the track width. Furthermore, since the information is recorded in the center of the tape, there is no gate for reproducing the information. When the tape is run in the opposite direction, the rotating head for monitoring (A'
) (B') as shown in FIG. If the signal is located at
2 times) higher than the signal track.
Trace the track of the signal next to the track. Therefore, the reproduction output by the rotating heads (A') (B') is the signal a j+ b j+a as shown in FIG.
The order is 1+ b2+ a l+ b l.

By the way, one frame is made up of two tracks.
For example, signal a7. b + signals constitute a frame, but in the relationship between the output during normal playback shown in Figure 3 (A) and the output during reverse playback shown in Figure 6, both of the signals of the tracks in the frame are Playback order is signal a4. bl
The order is the same.

Therefore, the operations of the signal processing circuit (3) and the deinterleave circuit (13) (see Figure 2), which perform frame-by-frame processing, are independent of the tape running direction and are often used in common. There is no need to add or change new circuits.

(G) Effects of the Invention As described above, according to the present invention, the signal processing circuit is controlled by the pair of monitoring rotary heads provided with a step difference relative to the pair of recording/reproducing rotary heads attached to the rotary head cylinder. etc. can be shared during normal playback and reverse playback, and the number of tape accesses such as high-speed searches can be reduced, making it particularly suitable for data recorders using rotary head magnetic recording and reproducing devices that have a large number of tape accesses. It is extremely beneficial to apply.

[Brief explanation of drawings]

The drawings are all related to the present invention, and FIGS. 1(a) and 1(b) show the head arrangement of the rotary head cylinder of the present invention, FIG. 1(a) is a plan view, and FIG. 1(b) is a plan view. FIG. Figure 2 is a simple block diagram showing the vicinity of the signal processing section, Figures 3 (a) and (b) are diagrams showing envelope signals during recording or playback, and Figure 4 shows the relationship between the tape and the rotating head during recording. FIG. 5 is a schematic diagram showing the relationship between the tape and the rotary head during reverse playback, and FIG. 6 is a diagram showing an envelope signal during reverse playback. (A), (B)... Rotating head for recording/playback, (A'), (B')... Rotating head for monitoring, (1)... Rotating helad cylinder, (3)...・Signal processing circuit.

Claims (1)

[Claims] (1) Tracks are formed on the magnetic tape by a rotating head, two adjacent tracks recorded by magnetic heads with different azimuth angles form one frame, and recorded/playback data is processed in units of frames. A magnetic recording/reproducing device is equipped with a pair of monitor rotary heads that retrace the tracks recorded by a pair of recording/reproducing rotary heads during a recording operation to monitor the recording state. The rotary head for the monitor is connected to the recording/recording head so that when the recording head is run in the opposite direction and at the same speed as when recording, the two tracks constituting one frame are played back in the same order as when recording.
A rotary head type magnetic recording and reproducing device characterized in that a rotary head for reproduction is provided with a step and is attached to a rotary head cylinder.