EP0126962A2 - Electronic keyboard musical instrument, and device for using it - Google Patents

Abstract

An electronic keyboard musical instrument is controlled by a main system computer depending on input elements. A voice module (VI) has a subsystem (6) with a subsystem bus (UB) and a memory (URAM) and microprocessor (UCPU) having a subsystem computer (UMC). A bus switch (BS) is provided for data exchange between the main and subsystem, which alternately connects the subsystem memory (URAM) with the main system bus (HB) and the subsystem bus (UB). This allows a "real time" data exchange between the main system and subsystem.

Description

The invention relates to an electronic keyboard musical instrument with input elements, such as sound release buttons and digital and / or analog control elements, with a main system which has a main system bus having data, address and control lines and a main system computer having memory and microprocessor, and with at least one voice module, which is connected to the main system computer via the main system bus and forms sound signals from parameters supplied by it as a function of the actuated input elements, and to a method for operating such an electronic keyboard musical instrument.

In a known electronic keyboard musical instrument of this type, each voice module generates the sound signal of a voice by piecing this signal point by point from stored digital values. These digital values are stored in the main system data memory as a table or based on a calculation by the main system computer. Any changes to the input data ten almost immediately lead to a change in the memory content and thus a change in the sound signal. However, if there are several voices, the data memory becomes very large and the working speed of the microprocessor is no longer sufficient to generate all voices acoustically perfectly.

The invention has for its object to provide an electronic keyboard musical instrument of the type described in the introduction, which works perfectly even when there are several voices or audio signals, but nevertheless reacts immediately to changes in the input data.

This object is achieved in that the voice module has a subsystem with a subsystem bus, which also has data, address and control lines, and a subsystem computer with a memory and microprocessor, and that a bus switch for data exchange between the main and subsystem is provided, which connects the subsystem memory alternately with the main system bus and the subsystem bus.

By using the subsystem computer, the main system computer is effectively relieved. The main system computer only needs to calculate new parameters for the relevant voice when the input data changes and to transfer them to the subsystem memory via the bus switch. The capacity of the main system computer is then available for other tasks. For example, it can poll I / O modules cyclically. The additional work for the subsystem computer is low, since there are no high demands placed on either the microprocessor or the memory. The bus switch that connects the subsystem memory alternately with the main system bus and the subsystem bus makes it practical Continuous data exchange between the main and subsystem, so that every change in the input data processed in the main system is transferred to the subsystem using the "real time method".

It is advantageous if the bus switch is designed for bidirectional data exchange. The main system can therefore receive feedback signals from the voice module, which is useful for some modes of operation.

In a preferred embodiment, the bus switch and the subsystem memory can be operated at twice the clock frequency of the main system microprocessor. Both the main system bus and the subsystem bus are therefore connected to the subsystem memory in every cycle of the main system microprocessor. This means that data can be exchanged in every cycle of the main system microprocessor. This does not pose any technical difficulties either, because there are commercially available switches and memories that have a much higher working speed than a microprocessor.

It is further simplified if the subsystem memory consists exclusively of RAM memory areas. Not only parameters for the sound signals are then transferred from the main system to the subsystem, but also the respective control program. This increases the flexibility of the instrument.

With particular advantage, the voice module has outputs for several voices dependent on the same subsystem computer. This further reduces the effort because a subsystem computer is not required for every voice.

A method for operating such an electronic keyboard musical instrument is characterized according to the invention in that the main system microprocessor and subsystem microprocessor are operated at the same clock frequency, but offset by half a cycle time, and in that the bus switch operates the subsystem memory during the second half of the cycle time of the main system microprocessor to the main system bus and to the subsystem bus during the second half of the cycle time of the subsystem microprocessor. The time-delayed mode of operation of the two microprocessors gives the possibility that the subsystem can process data of the main system with a delay of only half a cycle time.

Due to the fact that feedback is also possible due to the bidirectional data exchange, an operating mode is recommended in such a way that for each voice a sub-signal, the size of which corresponds to the instantaneous meaning of the voice in the overall sound, is written into the sub-system memory for each voice and if necessary, the main system computer compares all voucher signals and the voice with the smallest voucher signal stops. If the player requests a new voice, but all voice modules are still occupied, the voice that has the least importance in the overall sound and is therefore the least noticeable is stopped. The new voice can then take the place of the stopped voice.

In the simplest case, the occupancy signal is derived from the volume of the tone signal of the voice.

It is also expedient if all of the information that is required to generate a voice is given after the activation of a sound release button from Main system computers are transferred to the subsystem memory via the bus switch. In this way, the voice outputs of the subsystems can be assigned, regardless of whether in the upper manual, lower manual, pedal or automatic accompaniment, including the current registration, at the moment the sound is triggered, so that optimal use of the voices is possible. A new sound can also be assigned to keys that have been sent in succession.

Furthermore, parameters that change the voice can be updated from the main system computer via the bus switch into the subsystem memory while the subsystem is voting. Volume, frequency and other information can therefore be updated by the operator during the sound output.

• Fig. 1 ein Blockschaltbild des erfindungsgemäßen Tastenmusikinstruments,
• Fig. 2 das Blockschaltbild eines Stimmenmoduls,
• Fig. 3 ein Zeitdiagramm der Bus-Schalter-Arbeitsweise
• Fig. 4 das Blockschaltbild eines weiteren Stimmenmoduls und
• Fig. 5 das Blockschaltbild eines abgewandelten Stimmenmoduls.

The invention is explained below with reference to preferred embodiments shown in the drawing. Show it:

• 1 is a block diagram of the keyboard musical instrument according to the invention,
• 2 shows the block diagram of a voice module,
• Fig. 3 is a timing diagram of the bus switch operation
• Fig. 4 shows the block diagram of a further voice module and
• Fig. 5 shows the block diagram of a modified voice module.

• - Ein Bedien- und Anzeigefeld PAN1, das Bedientasten und zugehörige Anzeigeelemente für den Orgelbetrieb aufweist, z.B. Registerschalter zum Ein- und Ausschalten von Filtergruppen, Effekten, Tonkanälen u.dgl.
• - Ein Bedien- und Anzeigefeld PAN2, das digitale Eingabeelemente in der Form von Bedientastern und zugehörige Anzeigeelemente aufweist, welche einem eingebauten Rhythmusgerät und Begleitautomaten zugeordnet sind.
• - Ein Bedienfeld POT, das analoge, stetig veränderbare Bedienelemente, z.B. in der Form von Potentiometern aufweist, beispielsweise Sinus-Zugriegel-Lautstärke-Einsteller, Tonhöhenregler u.dgl.
• - Ein Obermanual OM mit Tonauslösetasten.
• - Ein Untermanual UM mit Tonauslösetasten.
• - Ein Pedal PD mit Tonauslösetasten.

An electronic musical instrument in the form of an organ is illustrated in FIG. 1. It has a peripheral part 1, the assemblies of which are located essentially at the front of the organ, and a functional part 2, which is arranged essentially inside the organ housing. In this exemplary embodiment, peripheral part 1 has the following assemblies:

• - A control and display panel PAN1, which has control buttons and associated display elements for organ operation, eg register switches for switching filter groups, effects, sound channels and the like on and off.
• - A control and display panel PAN2, which has digital input elements in the form of control buttons and associated display elements, which are assigned to a built-in rhythm device and automatic accompaniment.
• - A control panel POT, which has analog, continuously changeable control elements, for example in the form of potentiometers, for example sine drawbar volume adjusters, pitch controls and the like.
• - An upper manual OM with sound release buttons.
• - A sub manual UM with sound release buttons.
• - A PD pedal with sound release buttons.

The aforementioned modules are connected via a peripheral bus PB to a main system 3, which has a computer MC which contains a microprocessor CPU, a program memory ROM and a data memory RAM. With the help of the main system computer, the States of the input elements consisting of the sound trigger buttons, the digital and the analog control elements are queried cyclically and recorded in the data memory RAM. The main system computer MC also controls the display elements.

• - Eine Stimmenerzeugungs-Baugruppe 4 mit mehreren Stimmenmodulen V1, V2 und V3, die beim Betätigen einer Tonauslösetaste in Abhängigkeit von den betätigten Bedienelementen unter Steuerung durch den Rechner MC Tonsignale zu erzeugen vermag, die an einen Audio-Bus ausgebbar sind.
• - Eine Effekterzeugungs-Baugruppe 5 mit mehreren Effektmodulen E1, E2 und E3, welche der Nachbehandlung der von den Stimmenmodulen V1-V3 erzeugten Tonsignale dienen.
• - Eine Schlagzeug-Baugruppe D, die Schlagzeug-Audio-Signale auf den Audio-Bus AB ausgibt.
• - Eine Schnittstellen-Baugruppe IF, die eine bidirektionale Verbindung zwischen Hauptsystem-Bus und Audio-Bus ermöglicht.
• - Eine Verstärker-Baugruppe A, welche mehrere Lautsprecher L1 und L2 sowie einen Kopfhöreranschluß KH versorgt.

The main system 3 includes a main system bus HB which, like the peripheral bus, has address, data and control lines. The following modules of function part 2 are connected to this main system bus:

• - A voice generation module 4 with a plurality of voice modules V1, V2 and V3, which can generate sound signals upon actuation of a sound release button depending on the actuated operating elements under the control of the computer MC, which can be output to an audio bus.
• - An effect generation module 5 with several effect modules E1, E2 and E3, which are used for the after-treatment of the sound signals generated by the voice modules V1-V3.
• - A drum kit D, which outputs drum audio signals on the audio bus AB.
• - An interface module IF, which enables a bidirectional connection between the main system bus and the audio bus.
• - An amplifier module A, which supplies several speakers L1 and L2 and a headphone connection KH.

Furthermore, a connection device C is connected to the audio bus AB, which enables the connection of sound carriers, e.g. cassettes.

Fig. 2 shows the structure of a voice module V1, which can generate four voices simultaneously, each voice being formed from two tone curves and two envelopes. Accordingly, the voice module V1 has eight output registers AR. A subsystem 6 with a subsystem computer UMC, which has a subsystem memory URAM and a subsystem microprocessor UCPU, is used for voice generation. A bus switch BS can alternately connect the memory bus SB leading to the subsystem memory URAM with the main system bus HB and a subsystem bus UB. For this purpose, the clock speed of the bus switch BS is twice as high as that of the main system computer MC and subsystem computer UMC. In this way, both the subsystem 6 can take over data from the main system 3 and the main system can take over data from the subsystem. The main system loads the program for the subsystem as well as parameters for the four voices into the subsystem memory URAM.

The subsystem bus UB connects the subsystem computer UCPU, a multiple timer T, a memory access control circuit DMAC, a 12-bit digital-to-analog converter DAC1, an 8-channel multiplexer MUX1 with eight envelope register registers SH in the form of samples - And holding elements, a double-buffered 8-channel 8-bit digital-to-analog converter DAC2 and an arrangement of voice output switches designed as a crosspoint matrix CPM. There is also an ALO sequence control circuit. The subsystem microprocessor UCPU is used for initialization, the calculation of the envelopes and the programming of the multiple timer T, the memory access control circuit DMAC and the crosspoint matrix CPM. The multiple timer T determines the frequency of the four voices and the repetition frequency of the envelope calculation. He therefore gives four independent of each other Time signals TO, namely a sequence of time signals with the multiple frequency of the voices for each voice. The memory access control circuit DMAC causes the tone curve digital values for the four voices to be read out repeatedly from the subsystem memory URAM. The digital-to-analog converter DAC1 carries out the digital-to-analog conversion of the envelopes of the four voices, the individual values of which are then transferred to the envelope register register SH via a line HK and the multiplexer MUX1. Eight different envelope voltages are therefore applied to the DAC2 digital-to-analog converter via the HKB envelope bus. With the aid of the memory access circuit DMAC, this converter receives individual values from a table stored in the URAM data memory in order to generate eight tone curves. These values are transferred in eight channels via an intermediate memory ZS to digital output registers AR, multiplied by the respective envelope voltage and then passed as analog audio signals to the corresponding line of the 8-channel audio signal bus TSB. By means of the crosspoint matrix CPM, the audio signals are switched to one or more lines of the audio bus AB or switched off from these lines.

• Beim Initialisieren (Einschalten) wird mittels des Hauptsystem-Bus HB das Programm für die Untersystem-Mikroprozessor UCPU über den Bus-Schalter BS in die Untersystem-Speicher URAM geladen. Dieses Programm ist leicht änderbar, da es jeweils vom Hauptsystem bestimmt wird. Durch Wegschalten eines Resetsignals wird der Untersystem-Mikroprozessor UCPU gestartet und initialisiert die Baugruppen des Untersystems, wie Zeitgeber T, Kreuzpunkt-Matrix CPM, Speicherzugriffssteuerschaltung DMAC usw.

This results in the following sequence in operation:

• When initializing (switching on), the main system bus HB loads the program for the subsystem microprocessor UCPU into the subsystem memory URAM via the bus switch BS. This program is easy to change because it is determined by the main system. By switching off a reset signal, the subsystem microprocessor UCPU is started and initializes the modules of the subsystem, such as timer T, crosspoint matrix CPM, memory access control circuit DMAC, etc.

As soon as any tone is to be heard, regardless of whether it is triggered by a tone release button in the OM upper manual, the UM lower manual or the PD pedal or by an automatic accompaniment, the main system writes parameters (e.g. about 170 bytes) to the subsystem via the BS bus switch Memory URAM and then issues a start command to this memory. The subsystem microprocessor UCPU can read this start command after the next switchover of the bus switch and then generates the corresponding voice by setting the timer T, activating the memory access control circuit DMAC, connecting the crosspoint matrix CPM to the desired audio channel and envelopes calculates and outputs.

The timer T outputs time signals TO with a multiple of the desired frequency to the sequence control circuit ALO for the selected voice. This sends a transfer command DREQ to the memory access control circuit DMAC, which retrieves digital values of a tone curve for the selected voice from the subsystem memory URAM. As soon as this takes place, the sequence control circuit ALO is actuated by an acknowledgment signal DACK in order to emit a write signal WR to the buffer store ZS of the associated channel of the digital / analog converter DAC2. A priority circuit in the sequence control circuit ALO ensures that the transmission command DREQ belonging to the second tone curve of the selected voice and the corresponding write command WR are delayed by one working cycle. The digital values belonging to the same time signal are therefore written into the buffer of the corresponding channels of the digital-to-analog converter DAC2 at different times.

A digital output register AR is connected downstream of the buffer store ZS, into which the buffer store values are transferred when a store command XFER occurs will wear. This filing command occurs simultaneously with the time signal TO. The data, which is read in with a time offset, is therefore simultaneously converted and output from the output register ZR onto the audio signal bus TSB. The same time shift of the transmission commands DREQ also occurs if the time signals of two voices should occur at the same time.

The digital-to-analog converter DAC1 compiles the envelopes for the different sound signals from digital values calculated in the subsystem. Since this takes place in the time-division multiplex method, the analog values output via the one channel HK are distributed to the envelope register register SH using the multiplexer MUX1. The envelope curve voltages thus formed serve as a multiplication factor for the tone curve values supplied from the digital output register AR.

Since two envelopes and two tone curves are available for each voice, extremely complicated sounds can be generated from the two tone signal components. For example, sine + percussion or piano + strings can be generated at the same time. However, variable sounds can also be produced, for example a guitar with a string tone + plucked plectrum or, in the case of a pan flute, a sinus tone + noise or a beat due to opposite amplitude modulation of the components.

If all voices of all voice modules are occupied, but a new voice is to be heard, one of the voices currently running must be stopped. For this purpose, the subsystem microprocessor UCPU writes a voucher signal for each voice in the subsystem memory URAM, where the main system microprocessor CPU can call it up. The occupancy signal corresponds to the current volume of the voice and therefore gives a measure of its importance of the voice in the overall sound. If the sound is percussive, it will fade out automatically and the subsystem will report this with the voucher signal zero. By querying the voucher signals of all subsystems, if a new voice is to be issued, the main system can search for a voice module that is not fully occupied or, if all voices are currently occupied, search for the one with the lowest voucher signal and issue an abort command for it. The UCPU subsystem microprocessor reads this command and turns off the voice, whereupon the voucher signal goes to zero. Now the main system can start the new voice.

If the sound signal is to be switched off, the main system computer checks whether this sound signal is still running in the subsystem, that is to say that it is not percussive and has not yet been stopped, or that the percussive sound has not yet fully decayed. If necessary, he writes a release command for this voice in the subsystem memory URAM. The subsystem then goes to the release phase for the envelope calculation, which is shorter or longer depending on the envelope type and reports itself free with the receipt signal zero when the envelope has completely decayed.

In addition, the main system tracks the sub-system memories URAM at certain addresses to the volume levels, slalom settings and possibly other parameters that may change during the tone duration.

The voice output switches arranged as a crosspoint matrix CPM are used to switch the voices to specific post-treatment channels, depending on the type, so that they can be retained in the effect modules E1 - E3, or to suppress interference signals completely away from the audio bus lines when the voice is not busy.

The operation of the bus switch, BS is illustrated in Fig. 3. The top line shows the cycles N, N + 1, N + 2 ... of the main system microprocessor CPV, in the second line the cycles i, i + 1, i + 2 ... des offset by half the cycle duration UCPU subsystem microprocessor. The third line shows the switching signal or the switching state of the bus switch BS. The fourth line indicates how long the memory bus SB is connected to the main system bus HB and the subsystem bus UB. The memory bus SB is always connected to the associated bus of the main system or the subsystem in the second half of the respective computer cycle. This means that each microprocessor CPU and UCPU can read and write the URAM subsystem memory as if it were normally connected to the associated bus. Since the URAM subsystem memory works faster than the microprocessors, it is permissible that it is only connected to the respective microprocessor over part of the cycle time.

In the embodiment according to FIG. 4, the same terms as in FIG. 1 are used for the same parts. The main difference is that the sequence control circuit ALO acts directly on the subsystem microprocessor UCPU and, when the transfer command DREQ occurs, the background program of this microprocessor is interrupted and a transfer program is started. In addition, tone curves and envelopes are not simulated separately, but the digital values for the outgoing tone signal are calculated and put into the 1-channel digital-to-analog converter DAC3. The outputs of the downstream multiplexer MUX2 can therefore be placed directly on the output register AR, which is connected to the crosspoint matrix CPM via the audio signal bus TSB stand. The output register AR is preceded by a buffer store ZS which, when the store command XFER corresponding to a time signal TO occurs, simultaneously outputs the analog values of the sound signals belonging to the same voice into the output register, even if they were previously to have been treated in succession in the digital-to-analog converter DAC3 .

FIG. 5 illustrates a voice module that is only intended for one voice. Here, the values of the sound signal, which are already composed of the envelope curve and the sound curve, are in turn calculated and combined in the digital-analog converter DAC4 to form a sound signal. This can be applied to one of several audio bus lines using an MUX3 analog multiplexer.

• Hauptsystem-Mikroprozessor CPU
• Programmspeicher ROM
• Datenspeicher RAM
• Untersystem-Mikroprozessor UCPU
• Untersystem-Speicher URAM
• Bus-Schalter BS
• Zeitgeber T
• Speicherzugriffssteuerschalter DMAC
• Ablauf-Steuerschaltung ALO
• Multiplexer MUXI
• Multiplexer MUX2
• Multiplexer MUX 3
• Kreuzpunkt-Matrix CPM
• Digital-Analog-Wandler DAC1
• Digital-Analog-Wandler DAC2
• Digital-Analog-Wandler DAC3
• Digital-Analog-Wandler DAC4

wurden handelsübliche Bauteile verwendet.For all components, such as

• Main system microprocessor CPU
• Program memory ROM
• RAM memory
• UCPU subsystem microprocessor
• URAM subsystem memory
• Bus switch BS
• Timer T
• Memory access control switch DMAC
• Sequence control circuit ALO
• MUXI multiplexer
• Multiplexer MUX2
• Multiplexer MUX 3
• Cross point matrix CPM
• Digital-to-analog converter DAC1
• DAC2 digital-to-analog converter
• DAC3 digital-to-analog converter
• DAC4 digital-to-analog converter

commercially available components were used.

Claims (10)

1. Electronic keyboard musical instrument with input elements, such as sound release buttons and digital and / or analog control elements, with a main system which has a main system bus having data, address and control lines and a main system computer having memory and microprocessor, and with at least a voice module that over the! Main system bus is connected to the main system computer and forms sound signals from parameters it supplies as a function of the actuated input elements, characterized in that the voice module (V1 - V3) is a subsystem (6) with a data, address and Control system subsystem bus (UB) and with a memory (URAM) and microprocessor (UCPU) having subsystem computer (UMC) and that a bus switch (BS) is provided for data exchange between the main and subsystem alternately connects the subsystem memory to the main system bus (HB) and the subsystem bus (UB). 2. Keyboard musical instrument according to claim 1, characterized in that the bus switch (BS) is designed for bidirectional data exchange. 3. Keyboard musical instrument according to claim 1 or 2, characterized in that the bus switch (BS) and the subsystem memory (URAM) can be operated at twice the clock frequency of the main system microprocessor (CPV). 4. keyboard musical instrument according to one of claims 1 to 3, characterized in that the subsystem memory (URAM) consists exclusively of RAM memory areas. 5. Keyboard musical instrument according to one of claims 1 to 4, characterized in that the voice module (V1) has outputs for several voices dependent on the same subsystem computer (UMC). 6. A method of operating an electronic keyboard musical instrument according to one of claims 1 to 5, characterized in that the main system microprocessor and subsystem microprocessor are operated with the same clock frequency, but offset by half a cycle time, and that the bus switch the subsystem memory connects to the main system bus during the second half of the cycle time of the main system microprocessor and to the subsystem bus during the second half of the cycle time of the subsystem microprocessor. 7. A method of operating an electronic keyboard musical instrument according to one of claims 2 to 6, characterized in that for each voice from the associated subsystem computer, a voucher signal, the size of which corresponds to the instantaneous meaning of the voice in the overall sound, is written into the subsystem memory and if necessary, the main system computer compares all voucher signals and the voice with the smallest voucher signal stops. 8. The method according to claim 7, characterized in that the document signal is derived from the volume of the sound signal of the voice. 9. A method of operating an electronic keyboard musical instrument according to one of claims 1 to 5, characterized in that all the information that is required to generate a voice, in each case after the start of actuation of a sound release button from the main system computer via the bus switch in the subsystem - Calculator to be transferred. 10. The method according to claim 9, characterized in that during the voice output by the subsystem, the voice changing parameters from the main system computer via the bus switch in the subsystem memory can be tracked.

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