JPH0554472A - Device for controlling program searching - Google Patents

Abstract

PURPOSE:To provide a device in which damage is not caused in a tape driving mechanism and on a tape and by which time for program searching is shortened. CONSTITUTION:The tape is driven to a forward or reverse direction by a tape driving means 101. In order to search the head position of a program while a search in the forward direction is in motion, a means 102, by which the rising edge of the identifying mark for a program start is detected, is provided. When the edge is detected, a stop command for search in the forward direction is outputted by the means 103. Then, the complete stop of the movement in the forward direction due to the inertia of a motor and tape is detected by a means 104. At the complete stop, a search command for the reverse direction is given to the means 101 by a means 105. While searching in the reverse direction, program time is read by a means 106, and the quantity of an overrun tape is determined. And then, by a means 107, as the function of the overrun quantity, the speed of the reverse direction search is determined.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary head digital audio tape recorder (hereinafter referred to as R-DAT).
The present invention relates to a cue control device for a program, and more particularly to a cue control device that can improve a cue operation speed of a program.

[0002]

2. Description of the Related Art R-DAT has come to be widely used as a sound source for car audio in particular. One of the features of R-DAT is the search for the start position of the program recorded on the tape, that is, the so-called high speed of cueing.

That is, when searching for a program by the forward search, for example, a search from the beginning to the end of a 120-minute tape can be executed in about 40 seconds. FIG. 6 is an explanatory diagram of a cueing method in the conventional R-DAT. That is, as shown in (A), the S-ID (start ID) for indicating the beginning of the program together with the program on the tape.
Is recorded, and the program starts from the rising edge of S-ID.

Therefore, for accurate cueing, it is necessary to search in the forward direction and stop at the rising edge of the S-ID. (B) is a diagram for explaining a cueing process that has been conventionally used. First, as shown in (A), a forward search is performed, and when a rising edge of the S-ID is detected, it is determined that a forward search is performed. Stop direction search.

However, since the search speed is generally set to about 200 times the speed at the time of recording / reproducing, even if the forward search is stopped, the drive motor and the tape inertia cause an overshoot. Therefore, for example, when it is detected that the rotation speed detector installed directly connected to the motor has completely stopped, a backward search is performed as shown in (b) and a backward search is performed at the falling edge of the S-ID. To stop.

However, at this time too much overshoot occurs,
The forward search is performed again as shown in (c).

[0007]

In order to accurately find the cue, the forward search and the backward search are repeated several times. However, the repetition of the forward search and the backward search causes the following problems.

(1) Each time the search direction is reversed, the brake is actuated on the tape drive mechanism to damage the tape drive mechanism and the tape. (2) Since the forward search and the backward search are repeated several times, the cue time becomes long. The present invention has been made in view of the above problems, and an object of the present invention is to provide a program cue control device capable of shortening the cue time without damaging the tape drive mechanism and the tape. To do.

[0009]

FIG. 1 is a basic block diagram of a program cue control device according to the present invention. That is, the driving tape driving means 101 drives the tape on which the program, the program start identification mark, and the program time are recorded in the forward direction or the reverse direction.

A rising edge detecting means 102 for detecting the rising edge of the program start identification mark recorded on the tape is provided in order to search the head position of the program during the forward movement by the tape driving means 101. When the edge detection means 102 detects an edge, the forward search stop instruction means 103 outputs a forward search stop instruction.

After the forward search stop instruction means 103 outputs the forward search stop instruction, the stop detecting means 104 detects that the forward movement due to the inertia of the motor and the tape has completely stopped. The backward search command means 105 gives a backward search command to the tape drive means 101 when the tape drive means 101 is completely stopped.

During the backward search, the overshoot amount determining means 106
Reads the program time, and determines the amount of tape that has passed too far in the forward direction from when the forward search stop command is output until the tape drive means 101 is completely stopped. Then, the backward search speed determining means 107 determines the backward search speed as a function of the overshoot amount.

[0013]

[Function] When the backward search is started after the rising edge of the program start identification mark is detected and the forward search stop command is output and the tape is completely stopped, the overshoot amount is read and the reverse scan is performed according to this overshoot. Since the speed of direction search is controlled, accurate and quick cueing is possible.

[0014]

FIG. 2 is a hardware configuration diagram of an embodiment of a program cue control device according to the present invention. The control unit 21 is configured by a microcomputer system, and has a CPU 211, a memory 213, an input interface 214, and an output interface 2 centering on a bus 211.
Including 15.

The input interface 214 has an S-ID
The detection unit 202 and the P-time detection unit 206 are connected. The amplifier 20 from the output interface 215
A command signal to the motor 2011 for driving the tape in the forward direction or the reverse direction is output via 12.
The motor 2011 incorporates a rotation speed detection unit 204 using, for example, a Hall element to detect the rotation speed of the motor. The rotation speed signal detected by the rotation speed detector 204 is input via the input interface 214. It is input to the control unit 21.

FIG. 3 is a flowchart of a first cueing control routine which is stored in the memory 213 of the control unit 21 and is executed by the CPU 212. In step 301, the forward search speed factor NF is set. In step 302, the forward search command of the double speed ratio NF is output from the output interface 215, the motor 2011 is activated, and the tape is sent in the forward direction.

The S-ID detection unit 206 is the S-ID of the tape.
Read recording channel. S-ID in step 303
It is determined whether or not the rising edge of is detected, and if not detected, the process returns to step 302 to continue the search in the forward direction. If the rising edge of S-ID is detected, an affirmative decision is made in step 303, and the operation proceeds to step 304 to output a forward search stop command.

In step 305, the motor 2 is driven based on the output signal of the rotation speed detector 204 directly connected to the motor 2011.
It is determined whether 011 has completely stopped. Motor 20
If 11 is detected to be completely stopped, step 3
Proceed to 06 to read P-time (program time). Since the P-time is recorded with the program reproduction time with the beginning of the program being zero, the overshoot that occurs before the motor 2011 is completely stopped after the forward search stop command is output by reading the P-time. You can know the quantity.

The reverse search rate is determined as a function of the P-time read in step 307, and step 3
At 08, a backward search command is output. S in step 309
-It is determined whether the falling edge of ID is detected. That is, since the tape is searched in the reverse direction, the beginning of the program is detected as the falling position of the S-ID.

If not detected, the process returns to step 306 to read the P-time again. FIG. 4 is a graph 1 showing the relationship between the P-time and the double speed rate determined as a function thereof.
In this example, the horizontal axis represents P-time and the vertical axis represents the double speed rate.
That is, when the P-time is 9 seconds or more, the double speed ratio is 50, and it is determined that the double speed ratio decreases as the P-time decreases.

Therefore, the smaller the overshoot amount is, the lower the speed ratio of the backward search is, and if the backward search is stopped at the trailing edge of the S-ID, the program is accurately stopped at the beginning of the program. It should be noted that the tape produced by a general user generally records the P-time only for the first 9 seconds.

In this case, it is possible to deal with this by predetermining (for example, setting to 50 times) the double speed rate of the backward search until the P-time can be read. Further, in the case of a tape in which an A-time (absolute time) in which the reproduction time of the entire tape is recorded in addition to the P-time is recorded, this A-time is used to control the double speed ratio of the backward search. You can also

FIG. 5 is a flowchart of the second cueing control routine, in which the A-time TS at the time of detecting the rising edge of the S-ID is read between steps 304 and 305 of the first cueing control routine. Step 50
1 is added. Further, instead of step 306, step 502 for reading the A-time when the motor 2011 is completely stopped and step 503 for determining the overshoot amount ΔT (= T-TS) are provided.

Then, in step 307, the backward search speed factor is determined as a function of ΔT.

[0025]

As described above, according to the present invention, S
The overshoot amount until the motor is completely stopped after detecting the ID is detected, and the reverse search speed is controlled by this overshoot amount. Therefore, it is possible to accurately find the head without repeating the forward search and the backward search, and it is possible not only to reduce the damage to the drive mechanism and the tape but also to shorten the search time. ..

[Brief description of drawings]

FIG. 1 is a basic configuration diagram of a program cue control device according to the present invention.

FIG. 2 is a hardware configuration diagram of an embodiment of a program cue control device according to the present invention.

FIG. 3 is a flowchart of a first cueing control routine.

FIG. 4 is a graph showing the relationship between P-time and double speed ratio.

FIG. 5 is a flowchart of a second cueing control routine.

FIG. 6 is an explanatory diagram of cueing in the conventional R-DAT.

[Explanation of symbols]

 101 ... Tape drive means 102 ... Rising edge detection means 103 ... Forward search stop command means 104 ... Stop detection means 105 ... Reverse search command means 106 ... Overshoot amount detection means 107 ... Reverse search speed determination means

Claims (1)

[Claims] 1. A tape drive means (101) for driving a tape on which a program, a program start identification mark and a program time are recorded, in a forward direction or a reverse direction, and a program for forward search by the tape drive means (101). A rising edge detecting means (102) for detecting a rising edge of the program start identification mark recorded on the tape for searching the head position, and a forward search stop when the edge is detected by the edge detecting means (102). Forward search stop command means (103) for instructing, and the tape drive means (101) when the forward search stop command is output by the forward search stop command means (103).
Detection means (10) for detecting that the
4) and the tape drive means (1) by the stop detection means (104).
01) is completely stopped, it is based on a reverse search command means (105) for giving a reverse search command to the tape drive means (101), and a command from the reverse search command means (105). During the backward search, the program time is read, and after the forward search stop command is output from the forward search stop command means (103), the tape drive means (101) is completely stopped by the stop detection means (104). Overshoot amount determining means (106) for determining the amount of tape that has overshot in the forward direction
And a backward search speed determining means (107) for determining a backward search speed as a function of the overshoot amount read by the overshoot amount determining means (106).