Abstract:
An automobile radio/digital recording system is provided in which a digital recorder enables input either through the radio or through a microphone to be stored in the digital storage device and be played back through the automobile&#39;s radio system. Storage of information in excess of five minutes is available.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to recording information on an automobile radio either from within the auto, from a separate audio source or from the radio itself. 
     Frequently, while driving the driver wants to record information either because it is in the driver&#39;s mind, is information which has been or is being broadcast on the radio or is music so broadcast which the driver wants to record real time. 
     Previously, auto radios which included a separate record feature used the standard tape recorder found in auto radios. This mechanism generally proved unwieldy, expensive and not susceptible to widespread use. 
     Recently, digital recording has become more available for widespread use. This invention incorporates a digital recording mechanism within an auto radio so as to allow the digital recording system to record either from an oral source within the car or from the auto audio itself. 
     At present, the recording time which is available for digital recording is approximately seven minutes, but this may increase in the future. Additionally, when the digital memory is fully loaded, it will wrap around and record over previous recordings. The system operates by depressing command buttons or, alternatively, by orally instructing and commanding the auto radio. 
     The present system will be able to play back that which has been recorded through the auto sound system. When recording oral sounds using the microphone, the radio becomes muted so as to avoid background noise. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front view of an auto radio with additional record and play buttons. 
     FIG. 2 is a schematic diagram of an embodiment of the left channel of this invention with the right channel being identical. 
     FIG. 3 is a block diagram of a voice control system which can control the digital recorder of FIGS. 1 and 2. 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 illustrates the front panel 10 of auto radio 12 of an automobile, the front panel 10 comprising a plurality of conventional push buttons 14, a display panel 16, a CD receptacle 18, a volume control 20. In addition, and in accordance with this invention, a record button 22, a play button 24, an LED indicator 26 and a microphone 28 for voice recording is provided. An alternative embodiment incorporating a voice command system using the microphone 28 will also be described. 
     FIG. 2 illustrates a schematic diagram of an embodiment of this invention. The diagram of FIG. 2 is shown as operating with a Jensen XCC 8220 radio. This is a conventional radio available on the open market. Additionally, the electronic circuit of FIG. 2 comprises chips that are conventionally available, these being identified as an ISD 33240 which is a single chip voice record/playback device with a memory for storing the message; an 74HC4016 available from National Semiconductor which is an electronic switch which controls the direction of the audio input (radio or Mic) and output play radio or stored message; and a Zilog Z86C02 microprocessor which reads the key presses and processes commands accordingly. It controls the switch and ISD chip. Specific connections are made to specific pins of the chips as shown in FIG. 2, and one of ordinary skill in the art can practice the invention by using the identified chips, making the connections to the appropriate pins, utilizing components where illustrated in order to practice the invention. Additionally, Linear Technology LT1 121 chip is provided which is a five to 3.3 volt converter since the ISD chip requires 3.3 volts to properly operate. 
     The circuit of FIG. 2 is connected to the 5 volt input from a Jensen XCC8220 auto radio. Such 5 volt source is connected through a diode 30 (D1) connected in series to a 220 Ohm resistor 32 (R1) to pin 1 of Zilog microprocessor chip 34. The pin numbers of the chip are identified with the legend P1, while the port connector internal to the chip is identified on the right. Pin 3 is connected through a 47K Ohm resistor 36 (R2) to the 5 volt source while pin 4 is also connected through a 47K Ohm resistor 38 (R3) to the 5 volt source. Pin 4 is also connected through a record push button 40 to ground. Pin 3 is also connected through a play push button 42 to ground. Pin 18 of chip 34 is connected to pin 3 of ISD chip 44 while pin 17 of chip 34 is connected to pin 2 of ISD chip 44; pin 16 of chip 34 is connected to pin 28 of ISD chip 44; pin 15 of chip 34 is connected to pin 1 of ISD chip 44. Pin 14 of chip 34 is connected to ground. Pin 8 of chip 34 is connected to pin 13 of the electronic switch chip 46. Pin 8 of chip 34 is connected to the mute line of the Jensen XCC8220 receiver. A microphone input is connected to pin 1 of chip 46 while the radio input is connected to pin 3. Pins 9 and 11 of chip 46 are connected together and to the input to the left power section of the Jensen XCC8220 receiver. This system utilizes the left channel of the Jensen receiver, although a duplicate chip 46 for the right channel could be provided if such additional channel audio was desired. Note that 5 volts is supplied to pin 14 of chip 46. The left radio input is supplied not only to pin 3 but also to pin 10 f chip 46. Pins 8 and 9 of chip 34 are connected to pins 5 and 6 of chip 34 while also being connected to pins 13 and 14 respectively of chip 46. Pin 7 of chip 46 is connected to ground. Pin 8 of chip 6 is connected to pin 13 of the recorder playback chip 44. Pins 4, 11, 12, 23 and 26 of chip 44 are connected to ground. Pin 14 of chip 44 is connected through a 1 μF capacitor 46 (C5) to ground. Pin 27 of chip 44 is connected through a 0.1 μF capacitor 48 (C2)to ground as well as to pin 18 and through a 0.1 μF capacitor 50 (C4) to ground. Pin 27 is also connected to receive the 3.3 volt input with a spike detector comprising a 22 μF capacitor 52 (C3) to ground. Pin 16 of chip 44 is connected through a 0.1 μF capacitor 54 (C7) to ground. Pin 17 is connected through a 0.1 μF capacitor 56 (C6) to pin 2 of chip 46. Additionally, pin 2 of chip 46 is connected through a 47K Ohm resistor 58 (R4) to ground and through another 47K Ohm resistor 58 (R4) to ground. Pin 4 is connected to pin 2 while pine 3 is connected to pin 10 of chip 44. Pin 4 is also connected through a 47K Ohm resistor 60 (R5) to ground. Other pin connections are shown in FIG. 2. 
     Although only play and record functions are illustrated in FIG. 2, other functions such as review, cure and fast forward can be added by those skilled in the art. At present a minimum of 2 MB memory is desirable for about seven minutes of storage but larger memory capacity may be desirable. The diagram presented in FIG. 2 illustrates a preferred embodiment of the present invention for the left channel, and a duplicate is provided for the right channel if audio from such channel is desired. 
     FIG. 3 is a block diagram of a voice control command system for the digital recorder of this invention. 
     Microphone 28 is employed as the input to a voice recognition DSP microprocessor 70. One output of microprocessor 70 is connected as a microphone input 72 to switching device 74; another input to switching device 74 is supplied from the car stereo input 76. Switching device 74 is connected through control lines 78 to transmit or receive information from microprocessor 70 and ISD recorder 33240 which is the same ISD microrecorder 44 as found in FIG. 2. ISD recorder 44 supplies its output to the car stereo in the manner as described with respect to FIG. 2. The voice recognition DSP microprocessor can receive and understand voice commands such as record/radio, record/voice, play, next message, and many other oral commands. Depending upon the oral command, switching device 74 connected to control lines 78 will provide command signals to control the operation of the digital recorder, much as the manual push buttons 22 and 24 would do if the manual system were the command control system for this invention. 
     This invention is described with reference to the present embodiment. The scope of protection for the invention is that defined by the claims appended hereto. Reasonable modifications, changes and variations may be made by those of ordinary skill in the art which will fall within the scope of the appended claims.