Abstract:
A multiple audio signal processing system is disclosed which comprises: a composite system combining a digital audio tape recorder and a compact disc player; a system controller for controlling the operation of the composite system in accordance with the data inputted into a data input of the composite system; and a signal path control circuit for deciding the signal paths in accordance with a series of control signals outputted from the system control circuit. The device of the present invention makes it possible that the output signals of the compact disc player and input signals from the external can be selectively recorded on a tape loaded in the deck of the digital audio tape recorder, and the output signals of the digital audio tape recorder and the compact disc player can be outputted to the outside in accordance with the desire of the user.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a multiple audio signal processing system, and particularly to a multiple audio signal processing system which is used for a composite system constituted by combining at least two systems such as a digital audio tape recorder and a compact disc player wherein the output signals of the compact disc player or the line input signals from the external source can be selectively recorded on the digital audio tape recorder, and the output signals from the above-mentioned two systems can be selected and outputted to the outside. 
     BACKGROUND OF THE INVENTION 
     Generally, the storage and transmission of various kinds of information are being digitalized with the advent of the information society, and further, in some countries, digital information eras have been entertained because compact discs and their PCM broadcastings using satellites have been extensively supplied. 
     Digital audio tape recorder is one of the fields which the digitalization of information is becoming more advanced. 
     Unlike the compact disc players and the unilaterally transmittable PCM broadcastings, digital audio tape recorders make it possible to arbitrarily record and regenerate various kinds of information. 
     If output signals of the compact disc player are desired to be recorded onto a tape of the digital audio tape recorder, the input and output terminals of the two systems should be connected by means of a line, and the sampling rates of the two systems should be the same each other. 
     If the sampling rates of the two systems are different from each other, no reproduction can be made by the above mentioned method, and therefore, there is the problem that an expensive digital analogue converter has to be installed within the digital audio tape recorder. 
     SUMMARY OF THE INVENTION 
     Therefore, it is an object of the present invention to provide a multiple audio signal processing system of a composite type which is constituted such that a compact disc player is installed within a digital audio tape recorder. 
     It is another object of the present invention to provide a multiple audio signal processing system of the above-mentioned composite type which is capable of recording the output signals of the compact disc player to a tape loaded in the deck of the digital audio tape recorder. 
     It is still another object of the present invention to provide a multiple audio signal processing system of the above-mentioned composite type, in which the output signals of the compact disc player or input signals from the external source can be selectively recorded on a tape loaded in the deck of the digital audio tape recorder, and the output signals of the digital audio tape recorder and the compact disc player can be outputted to the outside. 
     In achieving the above objects, the device of the present invention comprises: a means for forming a composite system in combining a digital audio tape recorder and a compact disc player; a system control means for controlling the operation of the composite system in accordance with the data inputted into a data input means of the composite system; and a signal path control means for deciding the signal paths in accordance with a plurality of control signals outputted from the system control means. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above objects and other advantages of the present invention will become more apparent by describing the preferred embodiment of the present invention with reference to the attached drawings in which. 
     FIG. 1 is a block diagram of the multiple audio signal processing system according to the present invention; and 
     FIG. 2 is circuital illustration of the multiple audio signal processing system according to the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     As shown in the block diagram of FIG. 1 for the multiple audio signal processing system according to the present invention, the composite system constituted by combining a digital audio tape recorder 100 and a compact disc player 200 includes a system control means 400, and the system control means 400 is constituted such that it is capable of controlling the operation of the composite system in accordance with the data inputted into a data input means provided within the composite system. 
     A signal path control means 600 is constituted such that it is capable of deciding the signal transmission paths in accordance with a plurality of signals (C 1  -C 4 ) outputted from the system control means 400. 
     A display means 500 is capable of displaying to the external the data inputted into a data input 300. 
     FIG. 2 is more detailed circuital illustration of the multiple audio signal processing system of FIG. 1. 
     In this drawing, a switch 610 which is provided within the signal path control means 600 selects the outputs from the signal processor 150 of the digital audio tape recorder 100 and from the signal processor 240 of the compact disc player 200 in accordance with the level of the control signal C1 outputted from the system control means 400, so that the selected signals should be outputted by a line through a D/A converter 612 and a low pass filter 614. 
     Meanwhile, another switch 620 selects the signals outputted from the signal processors 150, 240 of the digital audio tape recorder 100 and of the compact disc player 200 in accordance with the level of a control signal C2 outputted from the system control means 400, so that the selected signals should be outputted through a digital output circuit 622 and a buffer 624. 
     Still another switch 630 selects the signal incoming through the low pass filter 614 and the line-inputted signals in accordance with the level of a control signal C3 outputted from the system control means 400, the selection being made in such way that the clock frequencies of a low pass filter 632 and an A/D converter 634 should be equal to sampling frequency of the digital audio tape recorder 100. 
     Still another switch 650 selects the digital input signals and the signals passing through the digital output circuit 622 in accordance with the level of a control signal C4 outputted from the system control means 400, so that the selected signals should be supplied through a digital input circuit 660 to the signal processor 150 of the digital audio tape recorder 100. 
     The digital audio tape recorder 100 is provided with; a servo section 130 for being controlled by the system control means 400; a drum 120 for being driven by the servo section 130 and for recording and regenerating various signals; an amplifier 140 for recording and regenerating; and a signal processor 150. 
     The compact disc player 200 is constituted such that a servo section 210 is controlled by the system control means 400, and the picked-up compact disc regeneration signals are outputted through the signal processor 240. 
     The multiple audio signal processing system according to the present invention constituted as above will now be described as to its operations. 
     First, in order to regenerate the data recorded on a tape of the digital tape recorder 100, the relevant data is inputted into the data input means 300 of FIG. 2, and then the servo section 130 will be activated by the system control means 400 to drive the drum 120. 
     Accordingly, the data recorded on the tape are picked up, and are supplied through the regeneration amplifier 140 to the signal processor 150. 
     At this time, the system control means 400 will supply the required control signals to the signal processor 150, and at the same time, will also supply the control signals C1, C2 to the switches 610, 620. 
     Thus, the signals processed by the signal processor 150 will be supplied to each one of the terminals of switches 610, 620, and therefore, the output signals of the signal processor 150 will be supplied to both the digital output circuit 622 and the D/A converter 612. Here, the D/A converter 612 converts the inputted digital signals to analogue signals, and outputs the analogue signals through the low pass filter 614, while the digital signals which have passed through the digital output circuit 622 will be buffered by the buffer 624, and will be outputted as regeneration signals. 
     As described above, when the digital audio tape recorder 100 is operated under a regeneration mode, the control signals C3, C4 outputted from the system control means 400 will be in a &#34;don&#39;t it care&#34; state, and the compact disc player can be driven, although it is desirable not to drive it in order to save the power consumption. 
     Meanwhile, if the relevant data is inputted into the data input means 300 in order to regenerate the data recorded on a compact disc of the compact disc player 200, the servo section 210, after being activated by the system control means 400, will drive the pick-up section 220, so that the data recorded on the compact disc should be picked up, be amplified by the amplifier 230, and be supplied to the signal processor 240. 
     At this time, the system control means 400 will supply a proper signal to the signal processor 240, so that the signals outputted from the signal processor 240 will be supplied to the other ones of the terminals of the switches 610, 620. 
     These signals supplied to the terminals of the switches 610, 620 are selected in accordance with the control signals C1, C2 outputted from the system control means 400. 
     Therefore, the signals inputted into the switch 610 will be line-outputted in the form of audio signals through the D/A converter 612 and the low pass filter 614, while the signals inputted into the switch 620 will be outputted in the form of digital signals through the digital output circuit 622 and the buffer 624. 
     When the only compact disc player is operated under a regeneration mode, the control signals C3, C4 outputted from the system control means 400 may well be in a &#34;don&#39;t care&#34; state. 
     Now the operation of the system according to the present invention will be described for the case where line-inputted analogue signals are to be recorded on a tape of the digital audio tape recorder. 
     If the relevant data is inputted into the data input means 300 in order to record the analogue signals inputted into the line input terminal on a tape of the digital audio tape recorder, then the system control means 400 will output signals for driving the signal processor 150, the drum 120, and the servo section 130 of the digital audio tape recorder 100 in accordance with the inputted data, and at the same time, will output a control signal C3 to the switch 630. 
     Upon supplying of the control signal C3 to the switch 630, the analogue signals inputted through the line input terminal will be filtered by the low pass filter 632, and then, will be inputted into the A/D converter 634. 
     The signals supplied to the A/D converter 634 will be converted to digital signals, and then, will be inputted into the signal processor 150. 
     Here, the sampling clock rate of the A/D converter 634 is equal to the sampling rate of the digital audio tape recorder 100. 
     The signals which are converted to digital signals and are inputted into the signal processor 150 of the digital audio tape recorder 100 will be amplified by the sound-recording amplifier 140, and will be recorded on the tape 110 by the drum 120. 
     In the process of reproducing the line-inputted analogue signals onto the tape 110, if the control signals C1, C2 outputted from the system control means 400 are controlled, then the line-inputted analogue signals, i.e., the signals inputted into the signal processor 150 will be outputted in the form of line outputs or digital signals, as described above, owing to the function of the switches 610, 620. 
     Meanwhile, the operation of the system of the present invention will be further described below for the case where the output signals of the compact disc player 200 are recorded onto the tape 110 of the digital audio tape recorder 100 under the condition that the sampling rate of the digital tape recorder 100 is different from the sampling rate of the compact disc player 200. 
     If the relevant data is inputted into the data input means 300 in order to record the output signals of the compact disc player 200 onto the tape 110 of the digital audio tape recorder 100, then the signal processor 240 and the servo section 210 of the compact disc player 200 will be activated by the system control means 400, and consequently, the pick-up section 220 will pick up the data recorded on the compact disc to supply it to the amplifier 230. 
     The signals supplied to the amplifier 230 will be amplified to a proper level, and then, will be supplied to the other ones of the terminals of the switches 610, 620 through the signal processor 240. 
     Under such a condition, the system control means 400 will supply the control signal C1 only to the switch 610, so that the signals picked up from the compact disc will be supplied to the D/A converter 612. 
     The digital signals supplied to the D/A converter 612 will be converted to analogue signals, will be filtered by the low pass filter 614, and thereafter, will be partly line-outputted, and partly supplied to the other one of the terminals of the switch 630. 
     The signals supplied to the terminal of the switch 630 will be selected by the control signal C3 outputted from the system control means 400, and will be supplied through the low pass filter 632 and the A/D converter 634 to the signal processor 150. 
     Here, the clock sampling rate of the A/D converter 634 will be same as the sampling rate of the digital audio tape recorder 100. 
     Upon supplying of the signals through the A/D converter 634 to the signal processor 150, the signals will be recorded onto the tape 110 through the drum 120 and the sound-recording amplifier 140 controlled by the system control means 400. 
     In this case, the control signal C2 outputted from the system control means 400 is supplied to the switch 620 so that the output signals of the signal processor 150 should be selected, while the control signal C4 supplied to the switch 650 is placed on a &#34;don&#39;t it care&#34; state. 
     Now the process of recording the output signals of the compact disc player 200 onto the tape 110 of the digital audio tape recorder 100 will be described under the condition that the sampling rate of the digital audio recorder 100 is the same as the sampling rate of the compact disc player 200. 
     Referring to FIG. 2, in order to record the output signals of the compact disc player 100 onto the tape 110 of the digital audio tape recorder 100, if the relevant data is inputted into the data input means 300, then the signal processor 240 and the servo section 210 of the compact disc player 200 will be activated by the system control means 400, so that the signals picked up from the compact disc will be supplied to the amplifier 230. 
     The signals after being amplified by the amplifier 230 will be supplied through the signal processor 240 to the other ones of the terminals of the switches 610, 620. 
     Under this condition, the control signals C1, C2 outputted from the system control means 400 will be supplied to the control terminals of the switches 610, 620, so that the signals should be selected from the above mentioned terminals. 
     Meanwhile, the control signal C4 outputted from the system control means 400 will be supplied to the control terminal of the switch 650, while the control signal C3 supplied to the control terminal of the switch 630 is put to a &#34;don&#39;t it care&#34; state. 
     Accordingly, the signals picked up from the compact disc and selected by the switch 620 will be supplied through the digital output circuit 622, the switch 650 and the digital input circuit 660 to the signal processor 150 of the digital audio tape recorder 100, and then, the signals will be ultimately recorded onto the tape 110. 
     Finally the operating process for recording external digital signals onto the tape 110 of the digital tape recorder 100 will be described. 
     If the relevant data is inputted into the data input means 300 in order to record external digital signals onto the digital audio tape 100, then the system control means 400 will output the control signal C4, so that the switch 650 should select the signals passed through the buffer 640. 
     The external signals selected by the switch 650 will be supplied through the digital input circuit 660 to the signal processor 150 of the digital audio tape recorder 100, and then, will be recorded on the tape 110 as described above. 
     The present invention was described in the above based on the embodiment of FIG. 2. 
     But it should be understood that the function of the digital input circuit 660 of FIG. 2 can be merged with the signal processor 150, and in the case of a stereo system each one of an A/D converter 634, a D/A converter 612, and low pass filters 614, 632 should be added. 
     Further, the levels of the plural control signals C1, C2 outputted from the system control means 400 are determined in order that only one group from among the signals supplied to both of the input terminals should be selected, while the switches 610, 620, 630, 650 are analogue switches for selecting the signals supplied to both of the input terminals in accordance with the levels of the control signals C1-C4. 
     As described above, the present invention combines a digital audio tape recorder and a compact disc player in such a manner that pick-signals of a compact disc or signals inputted from the external source can be conveniently reproduced onto a digital audio tape depending on the desire of the user.