JPH02275500A - Voice recording and reproducing lsi device - Google Patents

Abstract

PURPOSE:To utilize a limited external memory effectively by providing a function which deletes unnecessary voice data when the unnecessary data is stored in an external memory, writing another data in the used areas closely in order, and changing address information correspondingly. CONSTITUTION:This device is equipped with an address register part 6 which holds address information on the external memory 9 for voice data storage, the memory interface part 7 consisting of an interface circuit for the external memory 9, a control part 4 which controls the operation of the whole device, etc. Specially, when unnecessary data is stored in the external memory 9 for voice data storage, address information on the voice data is deleted from the address register part 6. Further, following effective voice data are written in the area on the external memory 9 which is used by the unnecessary voice data closely in order and the address information on the respective voice data which is stored in the address register part 6 is changed correspondingly. Consequently, the memory 9 can be utilized effectively.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an audio recording/playback LSI device, and more particularly to an external memory management method for storing compressed and encoded audio data.

[Conventional technology]

Conventionally, as this type of audio recording/playback LSI, there are those shown in the block diagrams of FIGS. 3 and 4 and the memory pine pink diagram. By writing a recording command from the bus interface unit 8, this LSI performs A-D-D-A in response to the audio analog signal input from the input terminal 10.
The conversion unit 2 converts it into PCM data and further converts it into ADPCM data.
After being encoded into ADPCM data by the encoding/decoding unit 3, the memory interface unit 7 sequentially fills the external memory 9 for storing audio data from the first address and outputs the above-mentioned AD data.
At the same time as writing the PCM data, address information indicating the storage area of the external memory 9 to which the data has been written is stored in the address register section 6'. The above process was repeated for each message.

In addition, by writing a reproduction instruction command from the bus interface section 8, address information is read from the address register section 6', and the A stored in the external memory 9 is read through the memory interface section 7 according to the contents.
The DPCM audio data is taken in, decoded into PCM data by the ADPCM encoding/decoding unit 3, and then A-D
- After being converted into an audio analog signal by the DA converter 2, it was output from the output terminal 11.

[Problem to be solved by the invention]

The above-mentioned conventional audio recording/playback LSI performs a series of recording processes in which sequentially input analog audio signals are A-D converted, ADPCM encoded, and sequentially filled and written from the first address of the external memory 9 for storing audio data. Therefore, even if an unnecessary analog audio signal is input by mistake, the series of audio processing described above will be performed. Immediately after recording, this unnecessary part of the audio data can be deleted and a new recording can be performed to avoid wasting external memory. However, if the next message is recorded without deleting the unnecessary recorded portion, this portion will be wasted.

In the memory map diagrams of the external memory shown in FIGS. 4(a) and 4(b), if memory map areas #2 and #5 are unnecessary areas, these areas #2. If a message shorter than #5 is written, the memory can be used effectively, but this is virtually impossible. Furthermore, address registers are also allocated for this unnecessary area, which is extremely wasteful.

An object of the present invention is to eliminate such drawbacks, and when unnecessary audio data is stored in an external memory for storing audio data, to delete the address information of the audio data from the address register section, and to delete the address information of the audio data from the address register section. Subsequent valid audio data is sequentially filled and written into the area used by unnecessary audio data on the external memory, and the address information stored in the address register section is changed accordingly, so that the memory can be used effectively. An object of the present invention is to provide a voice recording/playback LSI device that has the following features.

[Means to solve the problem]

The configuration of the audio recording/playback LSI device of the present invention includes an A-D/D-A converter that converts an audio analog signal into PCM data, and converts the PCM data into an analog signal; and converts the converted PCM data into ADPCM data. encoded and also A
ADPCM that decodes DPCM data to PCM data
an encoding/decoding section; an address register section that holds address information of an external memory for storing audio data that stores several types of ADPCM-encoded audio data; and a memory interface section that includes an interface circuit with the external memory. a bus interface section consisting of a data bus interface circuit that writes commands to this device and reads status; a dynamic relocation control section that dynamically relocates the external memory; and a bus interface section that controls the overall operation of this device. When unnecessary audio data is stored in the external memory for storing audio data, the address information of the audio data is deleted from the address register section, and the unnecessary audio data is stored in the external memory for storing audio data. The method is characterized by sequentially filling and writing subsequent valid audio data into a usable area on the external memory for necessary audio data, and changing the address information of each audio data stored in the address register section accordingly. .

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of one embodiment of the present invention, and FIG. 2 is (a
), (b) are memory map diagrams of the external memory 9 in Fig. 1, and Fig. 2 (a) is before unnecessary data deletion processing, and Fig. 2 (b) is
indicates after unnecessary data deletion processing. Converts the audio analog signal input from the input terminal 10 into PCM data,
Also, an A-D-D-A converter 2 that converts the input PCM data into an analog signal and outputs it from the output terminal 11;
Encode PCM data to ADPCM data or AD
An ADPCM encoding/decoding unit 3 that decodes PCM data into PCM data, and an external memory 9 for storing audio data that stores several types of ADPCM encoded audio data.
, an address register unit 6 that holds address information of each audio data, a memory interface unit 7 that constitutes an interface circuit with the external memory 9, and a data bus that writes commands to this device and reads status. It is composed of a bus interface section 8 consisting of an interface circuit, a control section 4 that controls the overall operation, and a dynamic relocation control section 5 that performs dynamic memory relocation.

Next, the operation of this embodiment will be explained. During recording, a recording command is written from the bus interface unit 8, and the A-
After converting into PCM data in the D-D-A conversion unit 2 and encoding it into ADPCM data in the ADPCM encoding/decoding unit 3, the data is transferred from the memory interface unit 7 to the free area of the external memory 9 from the first address. and write ADPCM data. In this case, as shown in FIG. 2(a), memory areas #0 to #7 are stored and the rest becomes an empty area. At the same time, address information indicating the written storage area of the external memory 9 is stored in the address register section 6. The above process is repeated for each input voice.

During playback, a playback instruction command is written from the bus interface section 8, address information is read from the address register section 6, and the ADPC stored in the external memory 9 is sent through the memory interface section 7 according to the contents.
M audio data is taken in, decoded into PCM data by an ADPCM encoding/decoding section 3, further converted into an audio analog signal by an A-D-DA converting section 2, and outputted from an output terminal 11.

In this case, area #2. When deleting #5 (FIG. 2(a)), the address information of unnecessary data is deleted from the address register section 4, and as shown in FIG. 2(b), using the dynamic location control section 5, Subsequent valid audio data is sequentially filled and written into the shaded area of unnecessary data, and the address information stored in the address register section 4 is updated accordingly.

〔Effect of the invention〕

As explained above, the present invention, when unnecessary audio data is stored in an external memory for storing audio data, deletes the address information of the audio data from the address register section, and further deletes the address information of the audio data from the address register section. By having a function to sequentially fill and write valid audio data from then on to the used area on the external memory of the device, and change the address information of each audio data stored in the address register section accordingly, the limit can be reduced. This has the effect of making effective use of the external memory for storing the recorded audio data.

[Brief explanation of drawings]

FIG. 1 is a block diagram according to an embodiment of the present invention, and FIG. 2 (
a>, (b) are memory map diagrams of external memory for storing audio data in Figure 1, and Figure 3 is a conventional audio recording and playback LSI.
FIGS. 4(a) and 4(b), which are block diagrams of an example, are memory map diagrams of the external memory for storing audio data in FIG. 3. 1...LS1.2...A-D-D-A conversion section, 3.
... ADPCM encoding/decoding section, 4, 4'... control section, 5... relocation control section,
66'...Address register section, 7...Memory interface section, 8.8'...Bus interface section, 9...External memory, 0...Audio input terminal,...Audio output terminal.

Claims (1)

[Claims] Converts audio analog signals to PCM data, and also converts PCM
An A-D/D-A conversion unit that converts data into analog signals; an ADPCM encoding/decoding unit that encodes the converted PCM data into ADPCM data and decodes the ADPCM data into PCM data; an address register section that holds address information of an external memory for storing audio data that stores ADPCM-encoded audio data; a memory interface section that includes an interface circuit with the external memory; and writing commands to this device. and a bus interface section consisting of a data bus interface circuit for reading status; a dynamic relocation control section for dynamically relocating the external memory; and a control section for controlling the overall operation of the device. When unnecessary audio data is stored in the external memory for storing audio data, the address information of the audio data is deleted from the address register section, and the area used on the external memory for the unnecessary audio data is deleted. An audio recording/playback LSI characterized in that subsequent valid audio data is sequentially filled and written into the address register and address information of each audio data stored in the address register section is changed accordingly.
Device.