CN1295103C - Vehicular video-audio player - Google Patents

Abstract

The invention discloses a new car audio-visual player using a removable hard disk (U disk) as an audio-video carrier, which includes a U disk, selection buttons, a control panel, a radio circuit, a volume control circuit, a power amplifier circuit, a liquid crystal display and The loudspeaker is characterized in that it also includes a universal serial bus (USB) interface circuit, a central control and decoding circuit, and an internal storage circuit. The central control and decoding circuit searches through the USB interface and reads compressed video and audio information in the U disk, video, After the audio information is decoded by the central control and decoding circuit, it is restored to a video signal and displayed on the LCD screen, and the audio signal amplified by the power is played out through the loudspeaker. Because the present invention adopts U-disk as the carrier of audio-visual programs, U-disk, USB interface circuit, central control and decoding circuit are organically combined with the existing car audio circuit, so the present invention has large storage capacity of audio-visual programs, abundant sound sources, no Affected by vibration, the advantages of stable playback.

Description

New car audio and video player

technical field

The invention relates to a car audio-visual device, in particular to a novel car audio-visual player utilizing a removable hard disk (U disk).

Background technique

The audio-visual player that existing automobile is used is divided into two big classes: tape player and laser player (divided into: CD, VCD, DVD etc.). The audio-visual player for the car is specially used in the car, and the existing car audio-visual player has some fatal flaws due to the vibration generated during the driving of the car: 1. The tape player is technically and in terms of sound quality requirements. In other words, tape playback will tend to be eliminated due to poor sound quality, easily dirty magnetic heads, and tape technology in audio-visual high-fidelity technology. 2. Since the laser player reads data by laser reflection and has mechanical transmission inside the machine, the anti-vibration effect is extremely poor, which will cause interruption of music or pictures during playback; There will be scratches, and in severe cases, it will not be able to play; if the car CD player (CD player) needs to expand the storage capacity (generally a CD record stores 10-12 songs), it often uses multi-disc storage and playback, and the price of the machine is extremely high; The life of the laser head is short.

Contents of the invention

The object of the present invention is to provide a kind of new carrier as playing form, have the video-visual program storage capacity is big, sound source is abundant, not affected by vibration, the new-style vehicle audio-visual player that utilizes removable hard disk (U disk) of playing stable.

The purpose of the present invention is achieved like this: the present invention comprises removable hard disk, selection button, control panel, radio circuit, volume control circuit, power amplifier circuit, liquid crystal display screen and loudspeaker, control button is arranged on the control panel, is characterized in that also includes general-purpose Serial bus (USB) interface circuit, central control and decoding circuit, internal storage circuit, press the selection button and control button, choose to read the information of the removable hard disk, the central control and decoding circuit searches and reads through the universal serial bus interface circuit Take the video and audio information compressed in the removable hard disk. After being decoded by the central control and decoding circuit, the compressed video and audio information in the removable hard disk will be restored to a video signal and displayed on the LCD screen. The audio signal will pass through the volume adjustment circuit and power amplifier. After the circuit performs power amplification, it will be played out through the loudspeaker.

The internal storage circuit is composed of flash memory circuit and random storage circuit.

The present invention organically combines removable hard disk, universal serial bus (USB) interface circuit, central control and decoding circuit, internal storage circuit and existing car audio circuit because of adopting removable hard disk (U disk) as song carrier , so it has the following advantages:

1. Online video and audio compression formats (WMV, MP3, WMA) and other audio-visual programs are very rich and easy to download, so the audio sources are rich;

2. With the development of technology, the storage space of the U disk will continue to increase, so not only more and more songs can be stored in the U disk, but also multiple movies can be stored; (take the current 256M U disk as an example, It can store 68 audio-visual programs in MP3 format or nearly 300 audio-visual programs in Microsoft Windows media compression format (WMA format), and there will be 1G or even 10G U disk in the future.)

3. Audio and video programs compressed in MP3 or WMA format can fully meet the requirements of car audio and video;

4. Since there is no mechanical transmission during playback, it is not affected by vibration and the playback is stable;

5. The safety, stability and stability of the product are high, and the stored files are not easy to be damaged;

6. Low production cost.

Description of drawings

Fig. 1 is a block diagram of the present invention;

Fig. 2 is a schematic circuit diagram of the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with the embodiments and with reference to the accompanying drawings.

The present invention is composed of a removable hard disk, a universal serial bus interface circuit, a central control and decoding circuit U1, an internal storage circuit, a selection button, a control panel, a radio circuit, a volume control circuit, a power amplifier circuit, a liquid crystal display and a loudspeaker. There are control buttons on it, and the universal serial bus interface circuit is provided with an interface for plugging in a removable hard disk. The universal serial bus interface circuit is connected to the central control and decoding circuit through a connecting line, and the central control and decoding circuit is connected to the internal storage circuit through a connecting line. , LCD screen and volume adjustment circuit, the central control and decoding circuit can decode video and audio information in formats such as MP3, WMA, RM (Realplayer Media’s video compression format), AVI (video compression format), and the control panel through The connection line is connected with the selection key, and the selection key is connected with the universal serial bus interface circuit and the radio circuit through the connection line, and the radio circuit is connected with the volume adjustment circuit, the power amplifier circuit and the loudspeaker in sequence through the connection line.

The internal storage circuit is composed of flash memory circuit U2 and random storage circuit U3.

The universal serial bus interface circuit is composed of an interface J2 and resistors R7-R13. The data communication terminal 2 of the interface J2 is connected in series with the resistors R7 and R8 in sequence, and then connected to the signal input terminal 53 of the central control and decoding circuit U1, and the data communication terminal 3 The pin is connected in series with the resistors R9 and R10 in sequence and then connected to the signal input terminal 54 of the central control and decoding circuit U1, the ground terminal 4 pin of the interface J2 is connected in series with the resistor R11 and then grounded, and the resistor R12 is connected in series with the common terminal of the resistor R7 and R8 and the ground Between, the resistor R13 is connected in series between the common terminal of the resistors R9 and R10 and the ground.

The address terminals 17-23, 26-31, 34-38 pins (A0-A17) of the central control and decoding circuit U1 are respectively connected to the address terminals 25-18, 8-1, 48, 17 pins of the flash memory circuit U2 and the random storage circuit U3 address terminals 23-26, 29-34, 22, 35 pins, unconnected terminal 36 pins (NC) (No connection), component selection address terminals 20, 21 pins (BA0, BA1) (Bank Select address), column Address strobe pulse terminal 17 pins (CAS) (Column address strobe), row address strobe pulse terminal 18 pins (RAS) (Row address strobe), data input/output terminals 125-128, 2 of central control and decoding circuit U1 -6, 9-15 pins (DQ0-DQ15) are respectively connected to the data input/output terminals 29, 31, 33, 35, 38, 40, 42, 44, 30, 32, 34, 36, 39, 41 of the flash memory circuit U2 , 43, 45 pins and the data input/output terminals 2, 4, 5, 7, 8, 10, 11, 13, 42, 44, 45, 47, 48, 50, 51, 53 pins of the random storage circuit U3, the center The unconnected pin 39 (NC) of the control and decoding circuit U1 is connected in series with the resistor R14, and then connected to the unconnected pin 16 (NC) of the flash memory circuit U2, and the data input/output shielding pin 42 (UDQM) (Data input/output mask ) is connected to the data input/output shielding terminal 39 pins (UDQM) of the random storage circuit U3, the clock terminal 44 pins (CLK) is connected to the clock terminal 38 pins (CLK) of the random storage circuit U3, and the chip selection terminal 46 pins (CS) are connected to the random storage The chip selection terminal 19 (CS) of the circuit U3, the chip enable terminal 50 pin (CE#) (Chip Enable) are connected to the chip enable terminal 26 (CE#) of the flash memory circuit U2, and the clock enable terminal 56 pin (CKE) (Clock enable) is connected to the clock enable terminal 37 pin (CKE) of the random storage circuit U3, the write enable terminal 58 pin (WE#) (Write Enable) is connected to the write enable terminal 11 pin (WE#) of the flash memory circuit U2, The 59 pins (OE#) (Output Enable) of the output enabling terminal are connected to the 28 pins (OE#) of the output enabling terminal (OE#) of the flash memory circuit U2, and the 90 and 91 pins of the audio signal output terminals of the central control and decoding circuit U1 are respectively connected to the capacitor C1, C2 is connected in series to the left and right channel signal input terminals of the volume adjustment circuit.

The power supply detection and supply circuit is composed of voltage-stabilizing integrated circuits U4, U5, transistor Q, diode D, and resistors R1-R6. The power supply terminal 83 of the central control and decoding circuit U1 is connected in series with resistor R6 and then connected to the collector of transistor Q and the interface. The common end of pin 1 of the power supply terminal of J2, the base of the triode Q is connected to the power control terminal 124 of the central control and decoding circuit U1, the emitter of the triode Q is connected to the anode of the diode D, and the cathode of the diode D is connected to the central control and decoding circuit Pin 64 of the power supply terminal of U1, pin 72 of the power supply terminal of the central control and decoding circuit U1 are connected in series with resistors R3 and R2 in series and then connected to the cathode of the diode D, and pins 77, 81 and 89 of the power supply terminal of the central control and decoding circuit U1 are sequentially connected to the resistors R1 and R2 are connected in series to the cathode of diode D, resistor R4 is connected in parallel between the collector and emitter of transistor Q, resistor R5 is connected in parallel between the base and emitter of transistor Q, and the voltage stabilizing integrated circuits U4 and U5 The input terminal Vin of each is connected to pin 1 of the contact point of the working mode selection button SW2, the output terminal Vout of the voltage stabilizing integrated circuit U4 is connected to the power supply terminals 7, 24, 41, and 119 of the central control and decoding circuit U1, and the voltage stabilizing integrated circuit U5 The output terminal Vout is connected to the collector of the transistor Q, and the control terminal SHDN of the voltage stabilizing integrated circuit U5 is connected to the power signal control terminal 123 pin of the central control and decoding circuit U1.

The selection button SW2 is the working mode button, the selection button SW2 is pulled to the pin 1 of the contact point, which is the mobile hard disk playback mode, that is, the audio-visual mode state, and the button SW2 is pulled to the pin 2, which is the radio mode.

The control panel consists of power button SW1, press S1 to select the previous song, press S2 to select the next song, press S3 to pause, press S4 to play, press S5 for sound field mode, and resistors R15-R20. The common terminal of resistors R19 and R20 Connect the key signal control terminal 82 pins of the central control and decoding circuit U1. Press S1 to select a song, press S2 to select a song, press S3 to pause, press S4 to play, and press S5 in sound field mode to control the working state of the mobile hard disk.

Use process:

1. Audio-visual mode: first insert the universal serial bus (USB) device (such as removable hard disk, hard disk box with power supply and other USB devices) into the interface J2 of the universal serial bus interface circuit, then press the power button SW1, press Press the button SW2 to enter the audio-visual mode, the voltage-stabilizing integrated circuit U4 is powered to generate the working voltage of the central control and decoding circuit U1, and the central control and decoding circuit U1 starts to work. The central control and decoding circuit U1 detects whether there is a universal serial bus device connected to the universal serial bus interface circuit through the 83 pin of the power supply terminal, and if so, detects whether the external universal serial bus device provides a 5V working voltage through the 83 pin of the power supply terminal , if not provided, the power signal control terminal 123 outputs a high level to make the voltage regulator integrated circuit U5 work and output a 5V voltage, and at the same time the power supply control terminal 124 outputs a low level to make the transistor Q conduct, and the 5V voltage is output to The external USB device is powered, and the external USB device is powered to work, so the corresponding data (compressed video, audio information) in the external USB device is input through the data communication terminal 2 and pin 3 of the interface J2 respectively. The signal input terminals 53 and 54 of the central control and decoding circuit U1 are stored in the flash memory circuit U2 and the random storage circuit U3 respectively through the data bus and the address bus as required, and are called when the central control and decoding circuit U1 plays music.

When the MP3 working state control button is pressed, the voltage on the button signal control terminal 82 will change differently. The central control and decoding circuit U1 judges the situation of pressing the corresponding button by detecting these voltage changes, so as to make selection, play Sound, pause, sound field mode conversion and other corresponding operations. The central control and decoding circuit U1 sends the compressed video and audio information in the removable hard disk to the flash memory circuit U2 and the random storage circuit U3, and the flash memory circuit U2 and the random storage circuit U3 send the compressed video and audio information to the central control and decoding circuit U1 decodes and restores the video signal to be displayed on the LCD screen. The two-channel audio signal decoded and played by the central control and decoding circuit U1 is output through the audio signal output terminals 90 and 91, and sent to the volume adjustment through the capacitors C1 and C2. After the circuit is adjusted and the power amplifier circuit is amplified, it is broadcast to the speaker.

2. Radio mode: Press the radio button to enter the radio mode, then press the FM button or AM button to enter the FM band or AM band, and then adjust the tuning button to select the radio station you want to listen to.

Claims (2)

1. A new type of audio-visual player for a car, including a removable hard disk, selection buttons, a control panel, a radio circuit, a volume control circuit, a power amplifier circuit, a liquid crystal display and a speaker. There are control buttons on the control panel, and the control panel is connected through a connecting line It is connected with the selection button, the selection button is connected with the universal serial bus interface circuit and the radio circuit through the connection line, and the radio circuit is connected with the volume adjustment circuit, the power amplifier circuit and the speaker in turn through the connection line, and it is characterized in that: it also includes a universal serial bus Interface circuit, central control and decoding circuit, internal storage circuit, the universal serial bus interface circuit is provided with an interface for plugging in a removable hard disk, the universal serial bus interface circuit is connected with the central control and decoding circuit through a connecting line, the central control and decoding The circuit is connected with the internal storage circuit, the liquid crystal display and the volume adjustment circuit through the connection line, the control panel is connected with the selection key through the connection line, and the selection key is connected with the universal serial bus interface circuit and the radio circuit through the connection line. Among them, the universal serial bus interface circuit is composed of a connector (J2) and a resistor (R7-R13). The data communication terminal (2) pin of the connector (J2) and the resistor (R7, R8) are serially connected to the central control and decoding The signal input terminal (53) pin of the circuit (U1), the data communication terminal (3) pin and the resistors (R9, R10) are connected in series to the signal input terminal (54) pin of the central control and decoding circuit (U1), and the connector The ground terminal (4) of (J2) is grounded in series with the resistor (R11), the resistor (R12) is connected in series between the common terminal of the resistor (R7, R8) and the ground, and the resistor (R13) is connected in series with the resistor (R9, R10). ) between the common terminal and the ground; the address terminals (17-23, 26-31, 34-38) of the central control and decoding circuit (U1) are respectively connected to the address terminals (25-18, 8) of the flash memory circuit (U2) -1, 48, 17) pins and address terminals (23-26, 29-34, 22, 35) pins of random storage circuit (U3), unconnected terminal (36) pins, component selection address terminals (20, 21) Pin, column address strobe pulse terminal (17) pin, row address strobe pulse terminal (18) pin, data input/output terminal (125-128, 2-6, 9-15) of central control and decoding circuit (U1) ) pins are respectively connected to the data input/output ends (29, 31, 33, 35, 38, 40, 42, 44, 30, 32, 34, 36, 39, 41, 43, 45) pins and The data input/output terminals (2, 4, 5, 7, 8, 10, 11, 13, 42, 44, 45, 47, 48, 50, 51, 53) pins of the random storage circuit (U3), the central control and The unconnected end (39) pin of the decoding circuit (U1) is connected in series with the resistor (R14) to connect the unconnected end (16) pin of the flash memory circuit (U2), and the data input/output shielding end (42) pin is connected to the random storage circuit ( The data input/output shielding end (39) pin of U3), the clock end (44) pin is connected to the clock end (38) pin of the random storage circuit (U3), and the chip selection end (46) pin is connected to the selection of the random storage circuit (U3) The chip end (19) pin, the chip enable end (50) pin is connected to the chip enable end (26) pin of the flash memory circuit (U2), and the clock enable end (56) pin is connected to the clock enable end of the random storage circuit (U3) (37) pin, the writing enabling end (58) pin is connected to the writing enabling end (11) pin of the flash memory circuit (U2), and the output enabling end (59) pin is connected to the output enabling end (28) of the flash memory circuit (U2). ) pins, the audio signal output terminals (90, 91) pins of the central control and decoding circuit (U1) are respectively connected in series with the capacitors (C1, C2) and then connected to the left and right channel signal input terminals of the volume adjustment circuit; the internal storage circuit consists of a flash memory circuit (U2) and random storage circuit (U3). 2. The new car audio-visual player as claimed in claim 1, characterized in that: it also includes a power supply detection and supply circuit, and the power supply detection and supply circuit is composed of a voltage stabilizing integrated circuit (U4, U5), a triode (Q), a diode (D), composed of resistors (R1-R6), the power supply terminal (83) pin of the central control and decoding circuit (U1) is connected in series with the resistor (R6) and then connected to the collector of the triode (Q) and the power supply of the connector (J2) The common end of the terminal (1) pin, the base of the triode (Q) is connected to the power control terminal (124) pin of the central control and decoding circuit (U1), the emitter of the triode (Q) is connected to the anode of the diode (D), and the diode The cathode of (D) is connected to the power supply terminal (64) pin of the central control and decoding circuit (U1), and the power supply terminal (72) pin of the central control and decoding circuit (U1) is connected to the diode ( The cathode of D), the power supply terminals (77, 81, 89) of the central control and decoding circuit (U1) are connected in series with the resistors (R1, R2) in series and then connected to the cathode of the diode (D), and the resistor (R4) is connected to the triode in parallel Between the collector and emitter of (Q), the resistor (R5) is connected in parallel between the base and emitter of the triode (Q), and the input terminals (Vin) of the voltage stabilizing integrated circuits (U4, U5) are connected to work The contact (1) pin of the mode selection button (SW2), the output terminal (Vout) of the voltage stabilizing integrated circuit (U4) is connected to the power terminal (7, 24, 41, 119) pin of the central control and decoding circuit (U1), The output terminal (Vout) of the voltage stabilizing integrated circuit (U5) is connected to the collector of the triode (Q), and the control terminal (SHDN) of the voltage stabilizing integrated circuit (U5) is connected to the power signal control terminal ( 123) Feet.