JPS61182699A - Method for recording and reproducing sound signal by using solid state memory - Google Patents

Abstract

PURPOSE:To eliminate the initial interruption of reproduced sound signals at the time of reproduction by storing the indicating address of an address counter at the time of the audio signal is inputted at the recording mode and starting the reading from an address preceding by a predetermined time interval the stored count value at the time of reproduction. CONSTITUTION:It is intended that the user may repeatedly reproduce his own voice. When a switch 3 is turned ON to a record mode, a control circuit 4 transmits signals to an address counter 5 to set the write mode for a memory 7 so that its address is sequentially incremented from zero. When the audio signal is inputted from a microphone 1, the sound signals are applied to an adaptive delta modem circuit 6 and a sound detection circuit 9 so that the indicating address of the address counter 5 at this time is stored. During repro duction, reading is started from an address preceding a predetermined time interval the stored address and reading is repeatedly performed from a speaker 13.

Description

[Detailed Description of the Invention] [Industrial Field of Application] A solid state device used in a recording and reproducing device that A/D converts an audio signal from a microphone, etc. according to the present invention, records it on a solid state memory, and plays it back. This invention relates to a method for recording and reproducing a specific audio signal using a memory.

[Summary of the invention]

In the present invention, when an audio signal from a microphone or the like is A/D converted and recorded on a solid-state memory, the address counter of the memory is operated prior to inputting the audio signal. is detected and the address specified by the above address counter is detected and stored,
During playback, rc is designed to read out the memory using an address before the stored address as the start address. As a result, it is possible to eliminate cut-offs at the beginning of the reproduced audio signal during reproduction, and also to make effective use of the memory.

[Conventional technology]

The audio signal played from the study card for language practice or the audio signal from the microphone is A/D converted and recorded in solid-state memory, read out, converted to D/input, and then added to the speaker. Recording and reproducing devices have been proposed.

Such devices read solid-state memory over and over again.

Since it can be played repeatedly, it is ideal for language practice such as English conversation. The length of the audio signal recorded by this device is approximately several seconds, and the memory capacity is correspondingly large.

[Problems that the invention is supposed to solve]

This is a recording and reproducing apparatus using the above-mentioned solid-state memory.

When recording and playing back audio signals from a microphone.

When facing the microphone, press the input switch provided with your friend and rub it so that the device goes into recording mode.
As soon as the input switch is pressed, the memory goes into write mode and the address is advanced, so if the user does not press the switch and speak immediately, the latter portion of the audio signal will be omitted and written. Friend +C who prevents this must speak quickly.

Therefore, when the audio signal from the microphone is detected and the microphone is pressed once to enter the recording mode, if the audio starts with a voiceless consonant, the voiceless consonant first enters a silent period, causing the beginning of the audio to be cut off. Time constant l of Mayu voice detection circuit
Cutting off the head also occurs due to the long attack time.

[Elaborate means to solve problems]

In the present invention, the special number recorded in the above-mentioned device is
Set to recording mode and advance the address counter. In this state, when an audio signal is input, the count value of the address counter is memorized. During playback, read out the address a predetermined period before the memorized count value and use it as the start address. I try to do this.

[Effect]

By truncating the beginning of the audio, memory can be used effectively.

〔Example〕

Figure @1 shows the implementation sequence of t#h when the present invention is applied to the above-mentioned learning card player.
Providing this microphone input terminal allows the user to repeatedly play back his or her own voice, thereby making it a friend. still,
Figure 1 a % I for 6 points! A signal shown at a%e in Fig. 2 appears.

Referring to FIG. 1, a microphone 1 is connected to a microphone input terminal 2, and an input switch 3 connected to the microphone 1t is substantially connected to a control circuit 4. When this switch is turned on, the signal l at point a causes the device to enter the recording mode, and the control circuit 4 sends a clock of a predetermined frequency to the address counter 5, and also sets the adaptive delta modulation/demodulation circuit &'EE mode (encoding mode). . This puts the memory 7 into write mode, and its addresses are sequentially advanced from "0".

When an audio signal is input from the microphone 1 in this state, this audio signal is applied to the adaptive delta modulation/demodulation circuit 6 through the contact 8a of the changeover switch 8, and is also applied to the audio detection circuit 9.

In the modulation/demodulation circuit 6, the input audio No. 1 is
DM (adaptive delta modulation) converts the digital signal expressed by one bit. The data of this digital signal is written into the memory T starting from address S1. When the address advances to 82 after a slight delay from the start of this data writing, when an audio signal is detected by the audio detection circuit 9, the signal at point b becomes "Hl".
I stand up. Based on this signal l, the control circuit 4 detects the address S2, and adds the value of this s2 to the start address memory 1o from point d and stores it.

Since the above-mentioned speech signal is interrupted at intervals until it ends, for example, during a voiceless consonant period or between syllables, the signal at the above-mentioned point sometimes falls.The control circuit 4 controls the control circuit 4 to Addresses E1 to E5 at that time are added and stored from 6 points in the end address memory 111. In this case, E, to E3 are sequentially rewritten and stored, and the final address is the last end address of the audio signal. E5 is stored.

In this way, the audio data is transferred to address Sl of memory 7.
When data is written from 1 to E5 and the write mode continues until the final address N, the recording mode is canceled.

Next, the repetitive playback mode is entered, and the control circuit 4 sets the modulation/demodulation circuit 6 to the D mode (decode mode) together with the I component.
The memory 7 is set to read mode. At this time, the address counter 5 has the preset value S. is given from the control circuit 4. This SQ is an address S that is a predetermined period α before the start address S2 stored in the memory 10.

This is the value that indicates.

Therefore, since the counter 5 starts reading from address S0, address S where the beginning of the audio data is recorded is also read out. The read data is demodulated into the original analog audio signal by the modulation/demodulation circuit 6, and is applied to the speaker 13 via the amplifier 12. Then, when the address advances from the address E5 stored in the memory 111 to a predetermined period β and reaches B4+, reading starts again from the address So.

This readout is repeated, so microphone 1
The voice you spoke will be played repeatedly. During this repeated playback, only the audio data is read out, so there are no gaps even if the audio is short.

To stop the above-mentioned repetitive reproduction, turn on the stop switch 14.

To perform repeated playback using study cards, press switch 8.
The contact f3a@I is switched. Note that this switch 8 is normally closed at contact 8, and when the plug of microphone 1 is inserted, contact 8 is closed.
This is the switch.

When a learning card is inserted into the device f, it is detected and a start signal is applied to the control circuit 4. As a result, the card is first put into a recording mode, the card is reproduced, and the reproduced signal is recorded in memo No. 91. Next, the repeat playback mode is entered and the memory 7 reads f1% and 7? : An action similar to the action is performed and repeated playback is performed.

FIG. 3 shows the appearance of the learning card player.

FIG. 3 (Here, one side of the case is provided with a card insertion groove 21, a card running groove 22 connected to the card insertion groove 21, a speaker emitting part 23, a volume knob 24)
and microphone input terminal 2 and stop switch 1 in Figure 1.
4th class is provided. The learning card 251 has a magnetic tape 26 attached thereon, on which English conversations and the like are recorded for several seconds in length.

When learning using this learning card 25, insert the card 25 into the insertion groove 1#, and then
When the card 25 is pushed in, the card 25 is detected, the start signal is obtained, and the recording mode is entered.

As a result, the card 25 runs in the running groove 22, the tape 26 is played back, and the playback sound can be heard from the sound part 23. At the same time, the playback signal is ADMed and recorded in the memory 7I. and then repeated playback is performed.

When using the microphone 1, the plug of the microphone cord may be inserted into the input terminal 2.

〔Effect of the invention〕

Fixed memo IJI will always record audio data from the beginning,
During playback, reading is always performed from the beginning, so there is no chance of the playback audio cutting off at the beginning, and there is no need to speak immediately after pressing the microphone input switch. Furthermore, solid-state memory can be used more effectively.

[Brief explanation of the drawing]

FIG. 1 shows implementation F of the present invention! Block diagram showing AJ, 2nd
The diagram shows the timing chart of FIG. 1. FIG. 3 is an external view of the learning card player. Note that 1 drawing is used here, and t is used here. 1 ・－・・・・・・・・・・・・Microphone 4...
...... Control circuit 5 ......
・・・・・・Address counter 6 ・・・・・・・・・
...Delta modulation/demodulation circuit 7 ...
...Individual memory 9...Audio detection circuit 10...Start address memory.

Claims (1)

[Claims] When an audio signal is A/D converted and recorded in a solid-state memory, after the solid-state memory is set to write mode, the audio signal is input to an A/D converter and an audio detection circuit, and an audio detection signal is obtained. An audio signal recording and reproducing method using a solid-state memory, wherein an address indicated by an address counter in the solid-state memory is stored, and during reproduction, reading is started from an address a predetermined period earlier than the stored address in the solid-state memory.