DE2924647A1 - Memory system for music synthesiser - includes clock pulse oscillator and two analog multiplexers connected to memory by unit acting as A=D or D=A converter - Google Patents

Abstract

The method of storing and reproducing electrical signals, suitable for an electronic music synthesiser, converts analog signals into digital signals for storage, then in the reading mode converts the digital signals back to analog form. Each signal emitter (10) is connected by an analog switch (11) to a multiplier (18) for entry into the memory. Two analog multiplexers (13,16) for input and output signals are connected to the memory (12) by a unit (14 or 15) which acts as an A/D or D/A converter. The analogue to digital conversion and vice versa is controlled by a clock pulse oscillator (20). During an interrogation cycle of the memory, the analogue switch concerned is controlled for a reading operation for the memory, and is multiplied with a multiplicand as a multiplier. The signal emitter is controlled for a length of time so that it is combined with an input signal so as to obtain a predetermined output signal. The outputs of the analogue multiplier (16) pass through a holding member (17) with an operational amplifier (21) and a capacitor (22) for connection to an analogue switch.

Description

Procedure and arrangement for storage and

Reproduction of electrical signals The invention relates to a Method for storing and reproducing electrical signals, in which im Storage mode the electrical signals entered as analog signals via signal transmitters are converted into digital form and then saved, while in Reading mode for signal reproduction converts the digital signals into analog signals and routed via analog switches for further processing, as well as an arrangement for storing and reproducing electrical signals with at least one Signal generator, analog / digital and digital / analog converter, a memory and a Analog switch on which can be coupled to the signal transmitter and the digitall-analog converter Method and arrangement for storing and reproducing electrical signals is already known.

In this method and arrangement, as in following is described with reference to Figs. 1 and 2, by a signal transmitter, for example a potentiometer that generates analog signals. Each signal transmitter has an analog / digital converter assigned, so that in the case of a large number of signal transmitters one of the number of signal transmitters Corresponding number of analog / digitcl converters for storage or write operation in the memory as well as an equal number of digital / analog converters for reproduction of the signals are required. The large number of converters is particularly disadvantageous, when a high resolution of the electrical signals is required.

Instead of inputting analog signals using a potentiometer it is known to use a keyboard.

However, a keyboard has the disadvantage that there are no smooth transitions the electrical signal values are possible that furthermore no voltage control can be carried out is and ultimately not a sensible real-time operation, for example during use such arrangements can be implemented in electronic music synthesizers. By the use of a keyboard does not apply to the analog / digital converter, however a large number of digital / analog converters are unavoidable.

In contrast, the invention is based on the object of a method and to create an arrangement of the type mentioned at the outset, in which with little circuitry effort an optimal memory write operation and a optimal reproduction of the signals by reading the memory are possible.

According to the invention, this object is achieved by the subject matter of the patent claim 1 solved.

Further refinements of the method and preferred embodiments the arrangement for carrying out the method result from the subclaims.

For the transmission of the electrical signals entered by signal transmitters every signal transmitter is connected to an analog switch. When hiring a Signal transmitter, for example a potentiometer, the potentiometer is so long rotated until a signal fed to an actuator via the analog switch results in the desired output value.

The value of the signal transmitter set in this way is then displayed via an analog multiplexer fed to a single analog / digital converter, which the Implementation of the analog signals of all signal generators. After the implementation in digital form the digital signals are stored in a memory. Saved for reproduction Signals the memory is queried and the stored digital signals in analog form and then fed to a further analog multiplexer whose outputs are connected to holding members. About the holder links, each with a associated analog switch is connected, the stored Signal values fed to the associated blessed member.

With the arrangement according to the invention, the storage of electrical Signals with high resolution possible without the use of a large number of converters is necessary. A single analog / digital - ^^ er and a single one is sufficient Digital to analog converter; a single converter unit which can be controlled can also be preferred can be provided, optionally in analog / digital and digital / analog conversion mode is working.

To query the memory and to write the memory can a clock generator may be provided which, when holding elements are used, such a Can perform query cycle that the value of the holding elements remains constant. as On / off switches for the analog switches - preferably RS flip-flops are used, which is normally in the memory read mode appropriate Are in the switch position, but switched to write mode by a read control and can preferably also be set to write mode manually.

The signal generators, preferably in the form of potentiometers, generate Voltage signals, which can be stored with high resolution through conversion in digital form are.

The actuators connected to the analog switches need practical have no linearity properties, since only that input signal value is stored, which supplies a certain output signal of the actuator.

The arrangement according to the invention can advantageously be used in electronic Use music synthesizers, with the values set by the sounder after combination with the input signal of the actuator as output signal of the actuator determine certain signals or tones or other parameters.

Instead of potentiometers as signal transmitters, other voltage-generating Elements are provided. The setting of the signal generator can usually be not influenced by the signals read out in memory read mode.

In the following preferred embodiments of the method and the arrangement for carrying out the method with reference to the drawing for explanation further features described. The figures show: FIG. 1 a basic circuit diagram of a known one Arrangement for the storage and reproduction of electrical signals, Fig. 2 shows a possible embodiment variant of known digital / analog converters, and FIG. 3 shows a preferred embodiment of the storage arrangement according to the invention and reproduction of electrical signals.

Fig. 1 shows an arrangement for storing electrical signals according to the prior art, in which the electrical signals from a signal transmitter 1, for example in the form of a potentiometer, via an assigned Analog-to-digital converter 2 are fed to a memory 3. That way you can electrical analog signals that control the setting of the signal transmitter or potentiometer 1, are stored in memory 3 after conversion in digital form. the Signals stored in memory 3 can be called up by reading memory 3 and are converted into analog signals in a digital / analog converter 4.

After the conversion into analog signals in the converter 4, its output signals are forwarded for further processing via analog switches (not shown). At a Fig. 1 corresponding arrangement is thus one with the number of signal transmitters used 1 same number of analog / digital converters 2 and digital / analog converters 4 to be provided, which are connected to the common memory 3. So that will the circuitry complexity with a larger number of signal generators 1 is extremely high complex. Known analog / digital or digital / analog converters can preferably be used find monolithic transducers use. Their structure generally corresponds to in Fig. 2 shown system of R / 2R resistance ladders with subsequent summation of all, the respective bits reproduce the sub-streams. All digital / analog converters 4 and the transmission elements representing these transducers are common to the Storage 3 connected. With a large number of signal heads or Potentiometers 1, a considerable amount of circuitry is required to achieve the Storage and reproduction of electrical signals according to analog / digital and digital / analog conversion to enable. This disadvantage becomes particularly serious if it is higher Resolution, for example at 10 bits per electrical signal from each signal transmitter 1 is generated.

In the following, with reference to FIG. 3, the inventive Arrangement for storing and reproducing electrical signals described. According to FIG. 1, the arrangement consists of a signal transmitter 10 to which an analog switch 11 is connected. The analog switch 11 enables the storage of the from Signal generator 10 generated electrical signal in a memory 12, with the writing or storing the electrical signal of the signal generator 10 via a multiplexer 13 and an analog / digital converter 14 takes place. The number of signal transmitters 10 can be of any size. A separate analog switch 11 is provided for each signal transmitter 10 necessary. All outputs 11a of the analog switches 11 are connected to one common Multiplexer 13 connected, the time division multiplex via the analog switch 11 of the signal transmitter 10 transmits signals received and the single, common analog / digital converter 14 supplies, in which the generated by the various signal generators 10 electrical Signals are converted one after the other and then written into the memory 12.

The memory 12 is also connected to a digital / analog converter 15, which is connected on the output side to an analog multiplexer 16 and vice versa Way as the analog multiplexer 13 a time-division multiplexed transmission of the successive from the digital / analog converter 15 received Causes signals. the Outputs of the multiplexer 16 are connected to the associated analog switch via holding elements 17 11 connected, as can be seen from FIG. In the read mode of the memory 12 the analog switch 1 is controlled in the switch position shown in Fig. 3, whereby the digital signals read from the memory 12 after conversion into analog signals in the converter 15 and transmission through the multiplexer 16 at the outputs of the multiplexer 16 can be obtained; these analog output signals of the multiplexer 16, their values are stored in the associated thttegliedern 17, can thus via the analog switch 11 are transmitted to an associated actuator 18.

The number of inputs of the analog multiplexer 13 on the input side is obviously as large as the number of signal generators used. Corresponding is also the number of outputs of the analog multiplexer provided on the output side as large as the number of signal heads 10.

The described arrangement according to the invention is used on the input side and a single converter 14 or 15 on the output side, which may be can be formed by a single converter that does the analog / digital conversion in write mode and carries out the digital / analog conversion in the read mode of the memory 12. The holding members 17, the number of which is equal to the number of signal transmitters 10 used, are used for maintenance of the respective signal value retrieved from the memory 12, with in reading mode the arrangement must be designed such that the holding members 17 each have the exact Hold the value of the assigned analog signal read from the memory 12, whereby the signal value of one of the holding members 17 can be called up via the associated one at any time Analog switch 11 for electrical or electronic actuator 18 is possible.

The basic structure explained above with reference to FIG. 3 is supplemented according to Fig. 3 by a read-write control 19, on the one hand with the memory 12 and on the other hand with the analog switches 13 is in communication and the switch position of the analog switches required for read and write operation 11 as well as the addressing of the memory locations of the memory 12. A clock signal generator 20 is connected to the analog multiplexer 13 arranged on the input side and the output side provided analog multiplexer 16 and the memory 12 connected so that dependent from the clock frequency of the clock signal generator 20 to a constant polling cycle Writing into the memory or reading from the memory is guaranteed. The interrogation cycle also takes into account the fall time of the holding members 17, see above that the stored in memory 12 digital signals in a repetitive manner after conversion into analog signals via the multiplexer 16 to the associated holding elements 17 are supplied so that the holding members 17 store the exact analog value and thus the value delivered by the holding members 17 is not due to its own fall time is adulterated.

According to a preferred embodiment, the memory 12 can be a shift register be, so that when writing and reading the memory 12 by the clock frequency a sequential shifting of the storage locations is performed to the appropriate ones Write signals in successive memory locations or from successive ones Read memory locations. The holding members 17 are made according to a preferred embodiment each of an operational amplifier 21 and a capacitor 22, which is between the positive input of the operational amplifier 21 and ground is connected.

Between the output of the operational amplifier 21 and its negative A feedback is provided at the input. The rate of fall of the capacitor 22-than Storage element is, for example, a maximum of 1 millivolt / sec, which is why a query cycle in the A range of 1 KHz is preferred so that the holding members 17 have the exact analog signal value to save.

The electric or electronic actuator 18 has-preferably the function of a voltage control and can be a multiplier, its Input value y, multiplied by the output signal x of the assigned analog switch 11 the output signal z of the actuator 18 results. The actuator 18 can besides a multiplier also a field effect transistor or a light-dependent resistor be. RS flip-flops are preferred in conjunction with bidirectional FET switches provided, which is normally shown in Fig. 3, corresponding to the reading operation Take switch position. The RS flip-flops are preferably in the analog switch 11 can be manually reset to write mode (dashed switch position in Fig. 3), so that at any time by manual actuation after adjusting the signal generator 10 the new signal value can be written into the memory 12. To control the Analog switch 11 in the required for the read or write operation In principle, self-switching switching elements can be used.

In order to achieve a sufficiently high resolution of the signals generated by the signal generators 10 To obtain electrical signals in analog form, analog-to-digital and digital-to-analog converters are used 14 or 15 used with 10 bits. The clock rate of the clock generator 20 depends on the The number of signal generators 10 and thus the number of inputs of the multiplexer 13 and the number of outputs of the multiplexer 16 from. In general, the clock speed of the clock 20 are in the millisecond range. Used in place of the one from the op amp 21 and the capacitor 22 existing holding member 17 uses another holding member this has an extremely low and much smaller drop rate than 1 millivolt / sec the read operation of the memory 12, which takes place in a clocked manner, can be dispensed with, i. e. periodically polling the memory 12 to maintain that in the holding members 17 stored signal value can through suitable choice of retaining links 17 may be superfluous.

In the embodiment shown in FIG. 3 for the holding members 17 the negatively back-coupled operational amplifier 21 serves exclusively as a buffer, to discharge the capacitor 22 via the associated analog switch 11, the normally has low input resistance.

The storage, i.e. the writing of electrical signal values in the memory 12 and the reproduction (reading) of the electrical signals takes place as follows: The signal transmitter 10, preferably potentiometer, are in front of the Inscribed in a certain position so that the resistance value of the potentiometer will be changed. For writing, the associated analog switches 11 are in the Write mode (dashed switch position) controlled so that all signal transmitters 10 are connected to the assigned input of the analog multiplexer 13, and the multiplexer 13 simultaneously receives the analog electrical signals from all signal transmitters 10 receives. The potentiometer 10 provide voltage signals, at the tap of a external control voltage is applied. By the clock generated by the clock generator 20 so that each input of the multiplexer 13 is sampled and time-division multiplexed to the analog / digital converter 14 transmitted, which has as many outputs as for the desired resolution required number of bits is necessary.

With simultaneous control of the memory 12 by the clock of the clock signal generator 20 or addressing by the read-write control 19 are in digital form converted signals of the individual potentiometers 10 to specific memory locations of the memory 12 transferred and written.

Reading of the memory 12 is done in the reverse manner, i.

that the signals stored in memory 12 due to the interrogation cycle of the clock generator 20 are read successively from the memory 12, in analog form are implemented and fed to the multiplexer 16. The storage or holding members 18 are used to maintain the respective analog value, so that the from the Memory 12 read analog signals constantly at the holding members 17 - in reading mode -Available and via the associated analog switch 11 to the relevant actuator 18 are transferred.

The religious songs 10, according to a preferred embodiment Multipliers can be formed only have to have low linearity properties have, since when writing the signals of the potentiometer 10 the relevant The potentiometer is turned until the output signal z of the actuator 18 has the desired value. During the writing process, the output signal x of the relevant analog switch 11 not only the multiplexer 13 to the following Implementation and storage in the memory 12 supplied, but at the same time the Actuator 18 and gives the signal z, which can be checked visually or acoustically can, so that the adjustment of the potentiometer 10 is only ended when the signal value z corresponds to the actually desired value; the value x is in Memory 12 is stored and has such a value that by combination with the input signal y of the actuator 18 then also in the reading, i.e. reproducing mode the same desired signal z is obtained.

The described arrangement for storing and reproducing electrical signals has a comparably low circuit complexity because only a single analog / digital converter or digital / analog converter is provided must become. The storage of the analog signals in the holding members 17 prepares no problems and only marginally increases the circuitry Effort, since simple links can be provided to hold the analog signals. Instead of the potentiometer 10 as a signal transmitter, it is evident that others can also be used Elements are used which have the function of tension elements, so that each externally applied control voltage is converted and written into the memory 12 can be.

The method according to the invention and the arrangement according to the invention are preferably used in electronic music synthesizers. The ones from the Output signals generated by actuators 18 determine a desired amplitude value for audio signals or control voltages fed to the y input of the actuator and are fed back into the device from output x.y of the same actuator, to change the pitch, volume or any other parameter as desired.

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Claims (20)

Claims method for storing and reproducing electrical Signals, in which the electrical signals as analog signals in storage mode can be entered via signal generator, converted into digital form and then saved while in reading mode for signal reproduction the digital signals in Analog signals converted and forwarded for further processing via analog switches are, characterized in that the electrical signals in storage mode are entered in analog form by signal transmitters via an analog switch, that the analog signals from several signal generators are time-multiplexed to an analog-digital converter transferred to digital form for implementation and then saved, that in the read mode of the memory the memory is read and the digital signals of the memory are converted into analog form in a digital / analog converter that receive the analog signals time-division multiplexed and held in each case in a holding element will. 2. The method according to claim 1, characterized in that the transmission of the signals for analog / digital conversion in memory mode and for digital / analog conversion is clock-controlled in reading mode. 3. The method according to claim 1 or 2, characterized in that the Analog signals of the holding members via an associated analog switch each an actuator for further processing. 4. The method according to any one of claims 1 to 3, characterized in that that during an interrogation cycle of the memory, the associated analog switch in the memory read operation can be controlled. 5. The method according to at least one of the preceding claims, characterized characterized in that the analog signals queried in the memory read mode are used as multipliers be multiplied by a multiplicon. 6. The method according to at least one of the preceding claims, characterized characterized in that the setting of the signal transmitter is carried out until the electrical signal of the signal generator after combination with an input signal of the actuator in question, a predetermined output signal of the actuator results. 7. Arrangement for storing and reproducing electrical signals with at least one signal generator, analog / digital and digital / analog converter, a memory as well as an analog switch that can be coupled to the signal transmitter and the digital / analog converter, characterized in that the signal transmitters (10) each have an analog switch (11) are connected to a common analog multiplexer (13) that a single one Analog / digital converter (14> provided is the one between the Output of the analog multiplexer (13) and the memory (12) is connected that a the only digital / analog converter (15) is provided between the memory (12) and the input of a second analog multiplexer (16) is connected, and that the Outputs of the second analog multiplexer (16) via holding members (17) with one of the Analog switch (11) are connected. 8. Arrangement according to claim 7, characterized in that the output each analog switch (11) is connected to an actuator (18). 9. Arrangement according to claim 7 or 8, characterized in that the actuator (18) is an electrical or electronic component. 10. Arrangement according to at least one of claims 7 to 9, characterized characterized in that the actuator (18) is a multiplier. 11. Arrangement according to at least one of claims 7 to 10, characterized characterized in that the holding members (17) have an operation v # strengthener (21) and one Capacitor (22), and that the capacitor (22) in a bypass connection is provided for the operational amplifier. 12. Arrangement according to at least one of claims 7 to 11, characterized characterized in that a clock generator (20) is provided, the output of which has control inputs the multiplexer (13, 16) and the memory (12) are connected. 13. Arrangement according to one of claims 7 to 12, characterized in that that a read and write control (19) is provided. 14. Arrangement according to claim 13, characterized in that a control input the analog switch (11) is connected to the read and write control (19). 15. Arrangement according to at least one of claims 7 to 14, characterized characterized in that the memory (12) is a shift register. 16. Arrangement according to one of the preceding claims 7 to 15, characterized characterized in that the analog switches (11) by self-retaining switching elements are controlled. 17. The arrangement according to claim 16, characterized in that the switching elements RS flip-flops are. 18. Arrangement according to one of claims 7 to 17, characterized in that that potentiometers are provided as signal transmitters (10). 19. Arrangement according to at least one of claims 7 to 18, characterized characterized in that the signal transmitter (10) can be switched manually to memory mode are. 20. Arrangement according to at least one of claims 7 to 19, characterized characterized in that the analog / digital converter (13) and the digital / analog converter (15) are formed by a single, reversible unit.