JPS5827197A - Musical sound reproducer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a musical tone reproducing device for reproducing musical tone information from a memory or the like in multiple tones, and its purpose is to enable reproduction of multiple tones with a simple circuit configuration; To provide a musical tone reproducing device capable of performing performance and reproduction using a keyboard at the same time.

Hereinafter, specific embodiments of the present invention will be described based on the drawings.

In the figure, 1 is a memory that stores musical tone information such as pitch data and note/rest length data constituting a desired piece of music, and 2 is a central processing unit (hereinafter referred to as a central processing unit) that reads and reproduces the musical tone information written in the memory 1. A shift register 5 that is capable of storing, for example, 8 channels of multiple tones is connected to the CPU 2 via a data bus 3 and a control gate 4. 4, the pitch data sent from the CPU 2 is multiplexed, and the pitch data is shifted by a clock φ sent from a clock generator (not shown). The pitch data sent from the final stage of the shift register 5 by the shift operation is sent to the shift register 5 through the data bus 6 and the control gate 4.
It is now transferred to the first stage of the process.

The timing control circuit T controls the control gate 4, and controls the switching of the route connecting the CPU 2 and the shift register 5, the route connecting the data bus 6 and the previous stage of the shift register 5, and the timing of capturing pitch data. The timing control circuit 7 has a CP.
A command signal for requesting retrieval of pitch data for reproduction is applied from U2, and a clock φ is also applied to K.

Further, the clock φ is divided by the frequency dividing circuit 8 to a frequency division ratio corresponding to the number of channels of the shift register 50, for example, 1/8, and this frequency dividing circuit 8
The zero frequency output is added as a drive clock for the key scan counter 9. The key scan counter 9 scans the key switch circuits 10 arranged in a matrix corresponding to each key on the keyboard, and the counted contents are encoded by a decoder (not shown) to output signals for scanning the key switch circuits. The scan detection signal, which is applied to the circuit 10, corresponds to the key switch turned on by pressing a key on the keyboard (3).The corresponding pitch name signal is the OR gate 11 and the OR gate 12.
The signal is sent to a musical tone generation circuit (not shown) via the circuit.

On the other hand, the counted contents of the key scan counter 9 (indicating the note name) are input to the matching circuit 13 together with the pitch data sent from the shift register 5, and a match is made when there is pitch data that matches the counted value. A signal is output from the circuit 13 and sent to the tone generation circuit via the OR gate 12. Therefore, the scanning counter 9 also serves as a counter for reproducing multiple sounds.

Next, the operation of the apparatus of the present invention configured as described above will be explained.

First, when the musical tone reproduction system is initialized to start reproduction, musical tone information previously stored in the memory 1 is sequentially read out by the operation of the CPU 2. When the musical tone information to be output to the fi CPU 20 input/output board is set by this, a signal is output to the timing circuit 7, and in response to this, the timing circuit 7 selects one channel in the shift register 5. Then, the control gate 4 is switched from the route connecting the shift register 5 and the data bus 6 to the CPU 2 side, and the pitch data from the CPU 2 is taken into one channel in the shift register 5. Thereafter, in the same manner, the pitch data sent from the CPU 2 is taken into the shift register 5, and at the same time, the taken-in pitch data is sequentially shifted using the clock φ.

Note that although the embodiment shown in the figure shows an example of multiplexing of 8 channels, the musical tones that cannot be reproduced in multiple tones are generally divided into parts, and when this is taken into the shift register 5, the sound The channel of the shift register can be specified for each part using the extra bits of high data, and the same operation as described above can be performed. For example, in the case of a four-voice part, two bits are used to specify the channel for each part.

On the other hand, the pitch data for multiple tones taken into the shift register 5 is passed through the data bus 6 and the control gate 4 to the clock φ.
This clock φ is frequency-divided to V8 by the frequency divider circuit 8 and counted by the key scan counter 9, and this counted value is used as a shift signal that is sequentially sent out by the shift operation by the clock φ. It is compared with the data from register 5 and a match is detected. That is, while the count value takes a certain value, the contents of all channels of the shift register are searched to detect whether there is pitch data that matches the count value, that is, the data specifying the note name. If they match, a signal indicating the match is transmitted to a musical tone generating circuit (not shown) via the OR gate 12, addresses 110M in the musical tone generating circuit by phase, and outputs the waveform data stored in the ROM. If the signals are sequentially read out, passed through a low-pass filter, amplified, and then added to a speaker, musical tones corresponding to the contents of each channel of the shift register 5 will be reproduced in multiple tones.

At this time, the scanning counter 9 scans the matrix key switch circuit 1° of the performance keyboard to detect the key-on.

Therefore, when the player operates the keyboard, key data is detected and the signal is supplied to the tone generating circuit via the OR gates 11 and 12. The musical tone generation circuit generates musical tones at predetermined pitches based on the detected key data.

As described above, according to the present invention, since the key scan counter is also used as the multiple tone reproduction counter of the multiple tone shift register, the circuit configuration is simplified and multiple tone reproduction can be easily performed. At the same time, it is possible to perform performance using the keyboard and playback at the same time, which has the effect of allowing you to enjoy a variety of plays.

[Brief explanation of drawings]

The drawing is a block diagram showing an example of a musical tone reproduction device according to the present invention. 1... Memory, 2... CPU, 4... Control gate, 5... Shift register, γ... Timing control circuit, 8... Frequency dividing circuit, 9... Key scan counter , 10...Gee switch circuit, 11.・-12
...OR gate, 13...-number circuit. 1-□ (7)

Claims (2)

[Claims] (1) A shift register that sequentially captures pitch data sent out for playback, a counter that increments one kakunt value while the pitch data captured in this shift register goes around, and the counting contents of this counter. and a matching circuit that compares the data and the data sent from the shift register and sends out a signal when they match. (2) The musical tone reproducing apparatus according to claim 1, wherein the counter is a key scanning counter that scans a key switch circuit of a keyboard.