Chord performing apparatus for an electronic organ

A chord performing apparatus for an electronic organ with a chord-former, comprises control inputs for control signals defining the chord tone, and control inputs for control signals defining the chord type and control units which can be preset in accordance with a pattern of chord tones and chord types to be played and outputs which are scanned and controlled in the rhythm of the melody for performing the same function as the switch elements, connected with the control inputs of the chord-former.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a chord performing apparatus for an 
electronic organ with a chord-former, the latter being provided with one 
or more control inputs to which, via first switch elements control signals 
for defining the chord tone may be supplied and with one or more second 
control inputs to which, via second switch elements control signals for 
defining the chord type may be supplied, with a set of first and second 
presettable control units which, prior to the beginning of the playing, 
are set in accordance with a pattern of chord tones and chord types 
corresponding to the times or parts thereof of the piece of music to be 
played and in which the tones and chord types are presented in the rhythm 
of the melody, in a desired sequence, during the playing. 
2. Description of the Prior Art 
Electronic musical instruments with a chord-former, such as an electronic 
organ or an electronic accordion, have been used in the art. An example 
hereof is the Cosmovox organ, type F50. Over and above the simple organs, 
such organs have the advantage that by touching keys in the undermanual a 
complete chord is produced; the tone of this chord is defined by the key 
touched and the chordtype (major, minor, seventh degree, dim) is defined 
by a switch to be operated separately. 
Although playing a similar organ gives the beginner earlier satisfaction 
than playing a normal organ--one is released of playing the complete 
chords, using several fingers of one hand, which is so difficult, 
particularly at the beginning--it has been found in practice nevertheless 
that also this simplified playing is experienced by many as being too 
complicated, because particularly the co-ordination of both hands, the 
playing of two manuals at the same time and the touching of the right keys 
demand prolonged exercise. As a result thereof, the beginner does not 
derive that pleasure from the instrument he had imagined and often breaks 
off the study in an early stage. 
U.S. Pat. No. 3,889,568 (PIONEER) teaches an automatic chord performance 
apparatus for an electronic chord organ with a memory for selectively 
storing a limited number of typical chord patterns, said memory being 
combined with encoding and decoding means and controlling a chord 
selecting circuit with a tone generating circuit. Contrarily thereto the 
present invention proposes to use the existing chord generating circuit 
which is present in any automatic chord ogran and offers the advantage of 
easier programming, a wider choice with many variations, and the 
possibility to adapt the device to any kind of organ; it can be included 
at the factory but it is also possible to add it to already existing 
organs 
SUMMARY OF THE INVENTION 
With a view of the foregoing factors and conditions of the prior art the 
present invention is based on the principle that by making use of the 
possibilities presented by a modern electronic musical instrument, an even 
further simplification of the playing may be obtained if in a certain 
rhythm the chords belonging to the bars of a certain melody may be 
produced by the organ itself, while then the player needs only play the 
melody. The invention provides a control unit for an electronic musical 
instrument which makes this possible. 
This object is obtained in that the outputs of the first and second control 
units, which are scanned and controlled in the rhythm of the melody and 
which can perform the same function as the switch elements are connected 
with the first and second control inputs of the chord-former in such a 
manner that the set tones and chord types are generated via this chord 
former in this prefixed sequence. 
The control units are preset in accordance with the desired chords and 
kinds of chords; by scanning and controlling them in the rhythm of the 
melody to be played they control the chord-former, the result being that 
certain chords are presented in the rhythm of the melody. The player needs 
than only play the melody. 
The rhythm may be defined by a separate clock-oscillator, but preferably, 
more particularly in the case of an organ with rhythm unit, the control 
rhythm for the scanning will be derived from this rhythm unit. 
The chord-former known as such has a number of control inputs for defining 
the various chord-tones and a number of control inputs for defining the 
various chord types to which, via switch contacts provided in the musical 
instrument, for instance keys, a suitable control voltage (earth potential 
or a potential different from it) is supplied for determining the 
chord-tone and the type. Now, according to the present invention, the sets 
of control units are preferably provided with an input and with for each 
function mutually parallel outputs which are connected with the first 
resp. the second control inputs of the chord-former, while the inputs are 
connected consecutively to a suitable control voltage in the rhythm of the 
melody. 
The control units may be constructed in many different manners. A purely 
electromechanical embodiment comprises sets of multi-position switches, 
one set for each bar, of which the corresponding outputs are connected 
mutually and with the respective control inputs and of which the inputs 
are consecutively scanned and connected with a source of control voltage. 
These sets of multi-position switches may be fitted to a fixed panel, the 
player having to set the two switches of a set for each bar in accordance 
with the desired chord and the desired chord-type. 
The control units, however, may also be made up of one or more sets of 
conductor matrixes, arranged on a bearer either or not interchangeable, 
with intersecting input guides and output conductors between which 
connections may be made on the crossings. The connections may be permanent 
or e.g. be brought about by connecting pins on the crossings. 
The embodiment of the present invention with permanent connections is 
intended to be marketed with the music sheet on which the melody to be 
played is recorded; of course, this bearer, which may be made by using the 
technology of printed circuits, should be easily interchangeable, which 
with the modern connection plugs used with bearers with printed circuits, 
can be realized in a simple manner. 
The embodiments described in the foregoing form immediately the necessary 
electric connections for the transmission of control voltage to the inputs 
of the chord-former. However, interesting possibilities arise when the 
control units are made up of a programmable information bearer processed 
by a reading device. This bearer may be both an bearer to be optically 
read-out or a punchcard. 
Of course, the bearer may be moved through the reading device in the rhythm 
of the melody to be played using the signals generated thereby for 
controlling the inputs of the chord-former. Preferably, however, use will 
be made of a readout device for reading the information bearer, the 
outputs of which being connected with a memory in which the information 
arranged on the bearer can be recorded and from which this information may 
be readout for controlling the organ in the rhythm of the melody to be 
played. Before the playing of the piece of music is commenced with, the 
bearer may be readout rapidly and the information present therein may be 
stored in the memory; this memory is then read-out in the rhythm of the 
melody to be played and the signals obtained thereby control the 
chord-former. Particularly the known optical bearer in which the player 
has to fill up (blacken) the spaces corresponding with the various chord 
tones and chordtypes has the advantage of being cheap, of occupying little 
space and of leaving space for arranging certain instructions thereon. So 
it is possible, for instance, to mark the series of information places 
corresponding with chord tones and chordtypes in accordance with the 
arrangement of the keys in the keyboard, the known stave script or the 
Klavarskribo script. 
The information bearer may be a programmable bearer with magnetic parts or 
with electrically conductible parts. The series of positions corresponding 
with the inputs of the chord-former may be indicated thereon in binarily 
coded form, in which case a decoding device controlled by the information 
readout must be used, this device converting this binary information into 
information to be supplied direct to the 12 inputs of the chord-former and 
to be processed by the latter. These measures have the advantage to 
decrease the width of the information bearer; the twelve chord tones may 
be indicated with only four binary positions and the five chordtypes with 
two binary positions. The programming, however, is somewhat more cumbrous, 
as the user has first to code the number of the chord tone and chordtype 
in binary form and to arrange this code on the card, so that this 
embodiment does not lend itself to arranging a scheme of a key-board or of 
stave script or Klavarskribo script on the information bearer. 
This coding in binary form may also be used with the programcard with 
selector switches mentioned above in which case the coding thumbwheel 
switches are used. 
There exists the possibility of extending. The installation may be extended 
with control units for controlling the parts of the organ which generate 
the organ tones for performing a melody, which is very well possible 
particularly in the case of a binarily coded program card--on which much 
information may be arranged in a small compass and the processing thereof 
by means of a micro-processor which may be adapted to many embodiments. In 
this manner there arises the possibility of four-handed playing or, before 
starting an exercise, the pupil who uses a preset information bearer, can 
make the melody of the piece of music sound for himself. This possibility 
is particularly interesting for demonstration and teaching purposes. 
The features of the present invention which are believed to be novel are 
set forth with particularity in the appended claims. 
Other claims and many of the attendant advantages will be more readily 
appreciated as the same becomes better understood by reference to the 
following detailed description and considered in connection with the 
accompanying drawings in which like reference symbols designate like parts 
throughout the figures.

DESCRIPTION OF PREFERRED EMBODIMENT 
In order to best understand the present invention a description of a 
preferred embodiment thereof is provided accompanied by drawings. 
Initially referring to FIG. 1 a very simplified diagram is shown with 
reference to which the inventive idea will be explained. 
The parts drawn in FIG. 1 to the right of the dot and dash line 1 are 
present in a modern electronic organ. They comprise the, of course 
schematically indicated, chord former 2 with the portion 3 which, by 
supplying a suitable voltage to one of the inputs 4a-4l define which chord 
tone the chord former will produce, and part 5 which, by supplying a 
suitable control voltage to the inputs 6a-6d, defines which chord type 
(major, minor, seventh, dim) of the respective defined chord tone is 
generated. Furthermore, the figure shows schematically indicated by the 
rectangle 7, a suitable source of control voltage for the chord-former 2. 
By means of the switches 8a-8l, which in fact are contacts of keys of one 
complete octave of the undermanual, a suitable control voltage (which may, 
of course, also be earth potential) may be supplied to the inputs 4a-4l of 
part 3 which defines the chord tone; via switches 9a-9d a suitable voltage 
may be supplied to inputs 6a-6d of part 5 which defines the chord type. 
According to the present invention, extra connections, to be made with the 
available switches 8a-8l respectively 9a-9d, are formed before the 
performance of the piece of music and are activated in the rhythm of the 
melody to be played, for the consecutive supply of suitable control 
voltages to part 3 which defines the chord tone and part 5 which defines 
the chord type. A smilar connection should be activated for each bar or, 
in the case of quadruple time, for each two counts of a similar bar. 
FIG. 1 shows schematically how this is done with n twelve-position switches 
(in accordance with the twelve chord tones) ST1 . . . STn and n 
four-position switches SS1 . . . SSn. Of the twelve-position switches ST1 
. . . STN all the corresponding outputs, indicated with the addition a . . 
. l, ST1a . . . ST1l, ST2a . . . ST2l, ST1na . . . STnl are mutually 
interconnected and also connected with the inputs 4a . . . 4l of the chord 
tone definer 3, while of the switches SS1 . . . SSn, in a similar manner, 
the outputs SS1a . . . SS1d, SSna . . . SSnd are mutually interconnected 
and are connected with the inputs 6a . . . 6d of the chord-kind definer 5. 
In the rhythm of the melody to be played, the sets of switches ST1, 
SS1-SS2, SS2-STn, SSn are now consecutively scanned by the respective 
movable contacts of the scanning switches SR1 and SR2; for this purpose, 
of each switch ST1 . . . STn respectively SS1 . . . SSn the respective 
movable contact LT1 . . . LTn, LS1 . . . LSn is connected with outputs U1 
. . . Un on the one hand and U1' . . . Un' on the other hand of two 
scanning switches SR1 respectively SR2. The input of switch SR1 is 
connected with the output 7.sub.1 of the source of control voltage 7 which 
supplies control voltage for the inputs 4a . . . 4l, while the input of 
switch SR2 is connected with output 7.sub.2 of this source of control 
voltage 7 which supplies control voltage for the inputs 6a . . . 6d. The 
movable contacts of switches SR1, SR2 are intercoupled as schematically 
indicated with the dotted lines 10; they are driven jointly, as symbolized 
by the arrow 11, by the block 12 which represents the control of the 
switches SR1, SR2 which, via connection 13 is controlled from the rhythm 
unit 14 in the organ and which, in this rhythm, sequentially moves the 
switches SR1, SR2 step by step. 
Before the beginning of the playing, each switch ST1 . . . STn on the one 
hand and SS1 . . . SSn on the other hand is set in a certain position, 
always according to the chord to be generated in a certain bar or half 
bar. Subsequently the outputs U1 . . . Un, respectively U1' . . . Un are 
scanned by the two switches SR1, SR2 in the rhythm defined by the rhythm 
unit 14 which controls the movement 12 of the switches SR1, SR2 so that in 
this same rhythm a suitable control voltage is supplied at the inputs 4a . 
. . 4l on the one hand and 6a . . . 6d on the other hand for each bar or 
half bar, resulting in the production of a chord of which the tone is 
defined by input 4a . . . 4l 6a . . . 6d respectively to which at that 
moment a voltage is supplied. 
In a simple embodiment, the switches ST1 . . . STn, respectively SS1 . . . 
SSn might be rotary switches arranged on a panel and the switches SR1, SR2 
might be stepswitches, for instance as used in telephone circuits to be 
driven via drive 12. 
It is clear, however, that in a practical embodiment preference will be 
given to a construction in which more use is made of modern electronic 
circuits and components. So, for instance, the switches ST1 . . . STn, 
respectively SS1 . . . SSn might be replaced by panels with a fixed 
circuit between which connections, either or not permanent, are made. 
FIG. 2 shows schematically an example of such an embodiment and FIG. 3 
shows a cross-section thereof on an enlarged scale illustrating how 
connections may be made. 
Referring now to the embodiment of FIG. 2 a set of twelve conductors 21a . 
. . 21l and a set of four conductors 22a . . . 22d are arranged on the 
panel 20. These conductors are located on the upper face 23 of the panel 
20. On the lower face 24 of the panel 20 there are arranged a number of 
sets of two conductors; each set comprises a first conductor GT1 and a 
second conductor GS1; so there are n sets of which the final set is 
indicated by GTn, GSn. The functions performed by the adjustable switches 
ST1 . . . STn on the one hand and SS1 . . . SSn on the other hand have now 
to be performed by connections to be made selectively between each time 
one of the conductors 21a . . . 21l on the one hand and a conductor GT1 . 
. . GTn, by which always the tone of the chord to be produced is defined 
with a connection between one of the conductors 22a . . . 22l and the 
conductors GS1 . . . GSn by which the kind of chord is defined. The 
conductors 21a . . . 21l are connected with the inputs 4a . . . 4l which 
define the chord tone and the conductors 22a . . . 22d are connected with 
the inputs 6a . . . 6d which define the chordtype; the sets of conductors 
GT1, GS1 . . . GTn, GSn are again connected, via suitable dial switches, 
with the outputs 7.sub.1, 7.sub.2 of the source of control voltage 7, in 
the rhythm of the melody to be played. 
FIG. 2 further indicates how the conductor 21a is connected with the 
conductor GT1 which is symbolically indicated by a little circle 25 while 
the conductor 22b is connected with the conductor GS1, so that by the 
scanning of the conductors GT1, GS1 by the switches SR1, SR2 respectively 
the input of the definer of the chord tone and the input of the definer of 
the chord type now receives voltage for the next bar the conductor 21d is 
connected with the conductor GT2 and the conductor 22a with the conductor 
GS2, so that in the subsequent bar the input 4d and the input 6a receive 
control voltage. FIGS. 3a to 3c show in cross-section on a much enlarged 
scale, the situation in which there is no connection (FIG. 3a), a 
connection is formed by means of a plug pin (FIG. 3b) and a connection is 
made by meamns of a soldered connection (FIG. 3c). 
Specifically referring now to FIG. 3a the panel 23 comprises conductor 21b 
and the conductor GT1 between which there is no connection. Referring now 
to FIG. 3b the situation is shown in which there is a connection in the 
case between the conductor 21a and the conductor GT1 such as indicated by 
a circle 25 to which connection is formed by means of a plug pin 26. 
Finally referring to FIG. 3c the situation is shown in which a permanent 
connection is formed, namely between the conductor 21a and the conductor 
GT1 by means of the soldermass 27. It is clear that, with this embodiment, 
for each melody to be played a separate panel must be used. 
The connections with the conductors on the panels can be easily made by 
providing the panels with the known connectors, not shown in the figure, 
which may be arranged along two longitudinal edges of the panel 23. 
Instead of a panel of the form illustrated, use may be made of a suitable 
form of a known and commercial matrix-connection board with which, as is 
known per se connections between crossing sets of conductors can be 
realized. 
Instead of the scanning switches SR1, SR2, use may be made also of gates to 
be made conducting consecutively in the rhythm of the melody to be played, 
as referred to schematically in FIG. 4. The switch SR1 is replaced by the 
range of gates GR1.sub.1 . . . GR1.sub.n with the outputs U1" . . . UN", 
while the switch SR2 is replaced by the range of gates GR2.sub.1 . . . 
GR2.sub.n with the outputs U1"' . . . UN"'. Of the gates GR1.sub.1 . . . 
GR1.sub.n the first inputs are connected with the output 7.sub.1 of the 
source of control voltage 7, while of the gated GR2.sub.1 . . . GR2.sub.n 
the inputs are connected with the output 7.sub.2 of this source of control 
voltage 7. Of the gate GR1.sub.1 the input 2 is connected with the input 2 
of the gate GR2.sub.1 and also connected with the control output 12'1 of 
the control circuit 12'; of the gate GR1.sub.2 the input 2 is connected 
with the input 2 of the gate GR2.sub.2 and with the control output 12'2 of 
the control circuit 12', while of the gate GR1.sub.n the input is 
connected with the input 2 of the gate GR2.sub.n and with the control 
output 12'n of the control circuit 12'. 
Consecutively and in the rhythm of the melody, the outputs 12'1 . . . 12'n 
supply control voltage to two gates at a time; always one gate from the 
first set will be conducting at the same time as a gate from the second 
set, so that for instance the gate GR1.sub.3 is at the same time 
conductive with the gate GR2.sub.3. In this manner control voltage 
emanating from the source of control voltage 7 is consecutively supplied 
to the outputs U1 . . . Un respectively U1' . . . Un', these control 
voltages controlling the chord tone definer 3 the chord type definer 5, 
resp. 
In FIGS. 5a to 5c embodiments are shown of a program board with indications 
thereon which are intended to simplify the programming. 
FIG. 5a is a board 30 with connectors 31, 32 arranged along the two edges 
for respectively the horizontal conductors 33 and the vertical conductors 
34, on which program board, on the upper edge 35, from left to right, 
first the four chord types and then the twelve chord tones are indicated. 
FIGS. 5b and 5c are other embodiments in which corresponding parts are 
indicated by the same reference numbers; FIG. 5b shows a board 36 with, on 
the upper edge 37, from left to right, first again the indication of the 
chord type and then an illustration 38, showing part of the keyboard, by 
which is indicated direct with which chord-tone lines the keys correspond. 
Finally, FIG. 5c is a board 39 with, along its upper edge 40, first the 
names of the chord types and then an illustration with reference number 41 
of the keyboard in the known klavarskribo script. 
By means of integrated circuits and modern miniature components, an 
embodiment based on the principle of FIG. 4 can be made very compactly. 
However, interesting possibilities turn up when microprocessor 
technologies are used in combination with modern optically readable 
program cards. Such a card may be programmed in a manner analogous to the 
embodiment with the bearer with printed circuit in which there are at 
least twelve plus four (sixteen) ranges of program positions, but it is 
also possible to define the twelve chord-tone positions in a binary code 
for which purpose five code positions will suffice, while the four chord 
types may be coded with two code positions. This results in a relatively 
narrow program card, but then the player has to convert the twelve, 
respectively the four positions, first into a binary code before filling 
in the code positions accordingly. 
Actual practice has proved the average player to be capable of mastering 
such a conversion quickly by means of conversion tables. In fact, this 
requires a converter by means of which the digital code read after the 
reading of the respective positions, is converted again into the twelve 
plus four control values since, naturally twelve plus four inputs of the 
chord-former have to be controlled. 
The principle of digital coding may also be applied to the above 
embodiments provided with adjustable switches in which case the adjustable 
switches may be the known thumbwheel switches which supply the digital 
code directly. 
An embodiment based entirely on the technology of the micro-processors will 
be now described below. 
In FIG. 6, the block 100 represents the combination of switches and/or keys 
by means of which, via bus 190, the player may pass commands to the 
control unit 400, so that the desired operations may be carried out. These 
operations are, for instance, starting the playing, stopping the playing, 
repeating of a part, etc. 
The block 200' in FIG. 6 is analogue with the switchor program board 
described above, the latter with fixed circuit or programming pins. FIGS. 
9, 10, 11, 15 and 16 show an optically readable program card with program 
positions to be filled in, a black space in these figures corresponds with 
a closed switch or with a programming pin which makes an electric 
connection between a line and a column. By means of unit 200' a range of 
chords is programmed, of which range the chords will later on have to be 
supplied to the electronic organ in sequence via the bus 450 in response 
to a command from the electronic organ on line 680. The explanation of the 
symbols used in FIGS. 9, 10, 11, 15 and 16 with reference to FIGS. 12, 13, 
17 and 18 is not yet important and will be broached only with reference to 
FIGS. 7 and 8. For the present, can be said that a black, blank space 
respectively in the first five figures mentioned corresponds with a 
logical one, respectively, 0 in the other four figures mentioned. 
After the block 200' has been programmed, the control (block 400) is 
started. The electronic organ generates a pulse at each first or third 
tone of a bar, which pulse is supplied to control unit 400 via line 680. 
Upon receipt of the pulse, the control unit 400 gives the electronic organ 
600 the control signal for the right chord from the range of chords 
programmed in sequence with the block 200' for a preset time (touch) via 
the bus 450. The programmed words of the block 200' are then read column 
after column, a test being always carried out at an intersection either or 
not interconnected, between a column and the various ranges. Such a 
reading/scanning technology is known per se and there is no need to 
illustrate and explain it in further detail. 
In connection with costs the size of a switch board or program board 200' 
will generally be such that a song of an average length of time, i.e. an 
average number of bars, may be programmed. The result thereof is that a 
range of chords to be programmed cannot have an unlimited length. Also in 
connection with costs the use of a range or number of boards for long 
pieces of music is not an attractive solution. If such a board, for 
instance because of the price, is not removable and available in more than 
one unit, it is moreover necessary to program the one program board for 
each song to be played which is timeconsuming and, for instance, for organ 
lessons, undesirable. Making the program board 200' interchangeable with 
another similar board meets this drawback but, as stated, the costs of a 
number of boards may be prohibitive while the storage of the boards gives 
practical problems: measures should then be taken to ensure that no 
switches are operated unnoticed or that switches or programming pins are 
damaged. The solution of these problems lies in the use of inexpensive 
readable program cards and FIG. 7 shows the scheme of an embodiment 
according to the present invention which is based on the use of an 
inexpensive separate bearer for recording a range of chords of a song. For 
this purpose, program cards and punch tapes known per se, which are used, 
among others, for calculating machines, come into consideration. In order 
to enable a player to record personally a range of chords on indexable 
places of a card without bulky and/or expensive apparatus, be so-called 
striped cards are preferred of which FIGS. 9, 10, 11, 15 and 16 show some 
examples, or cards on which an electrically conducting layer may be 
applied an electrically conducting sticker or the lead of a lead-pencil on 
the card. 
Block 500 in FIG. 7 is a randomly accessible reading/writing semiconducting 
memory (RAM). Such memories are relatively cheap and to be had in various 
embodiments and dimensions. The available individual memories or 
compositions thereof may have such dimensions that the ranges of chords of 
several songs can be stored therein. When using this possibility, this 
should be taken into account when programming the card, when loading the 
card information into the memory and when reading the memory for use by 
the organ. In order to ensure that when playing the organ and after the 
end of a song the chords of a following song will not be used 
unintentionally, for instance by a spontaneously improvised and performed 
prolongation of the finale, it is necessary that the beginning and the end 
of the individual ranges of chord are marked as such. Therefor, there 
should be a beginning and an end-symbol, while it is also possible to 
state the number of chords and derive therefrom at which moment the range 
of cords has been finished entirely. The marking of the beginning and the 
end of a range of chords is also useful if it is desired to exchange a 
range stored in the memory for a new range. Furthermore, the control unit 
400 may be constructed in such a way that, by means of the beginning and 
end symbols, the contents of the memory may be arranged anew for optimum 
use of the capacity of the memory. If the number of individual ranges of 
chords/songs in the memory 500 is great, it is also preferred to number 
the songs. Preferably the number should then also be shown on the chord 
card. By keying a number which the player can read from the chord card 
later on or from his music sheet, it is possible to move quickly to the 
beginning of any range of chords/song in the memory 500. 
An installation built up of individual components demands relatively many 
components, also in case the range of chords of one song is stored, so 
that the manufacture thereof is expensive. In connection with the control, 
such as for the identification of the beginning/end symbols, the numerals 
of the song number and relative jumps in the memory, an installation in 
which several ranges of chords of a number of songs are stored requires 
even more components. In that case, the use of a so-called microprocessor 
is certainly to be preferred. The installation will then not only remain 
physically compact and inexpensive, but it will also very flexible with 
respect to later modifications. A similar embodiment will now be described 
in further detail. 
The number of types of chords to be used is four, namely major, minor, 
seventh, dim (although still other kinds of chords are not precluded), and 
the number of settings of the chords to be applied is twelve, namely C, C 
sharp, D, D sharp, E, F, F sharp, G, G sharp, A, A sharp and B. Then four 
times twelve makes fortyeight combinations are possible. By representing 
each combination in the form of a binary codeword, 6 bitwords suffice. 
Without coding the minimum word-width would be 4+12=16 bit; this is also 
the number of ranges used in the program boards described above. The 
numbers of kinds and settings of chords to be used are such that an easily 
readable coding may be obtained. FIG. 12 shows an example of a possible 
coding. The type of chord in this example is represented by 2 bits 
(b.sub.5 and b.sub.6), while the setting is represented by the four 
remaining bits (b.sub.1 to b.sub.4). Thus the code for the setting is the 
same for each of the types of chord which allows easy reading and quick 
programming and control of a program cord. The combination b.sub.1 to 
b.sub.6 =000000 may deliberately be taken up in the range of chords to be 
programmed because they are not taken up from the card into the memory. 
This is advantageous if it is desired to erase one or more chords 
programmed too many, or if it is desired to obtain a separation easily to 
be interpreted visually on a card. The remaining 15 combinations of the 
code according to FIG. 12 may be used for introducing additional 
information on the card, e.g. with regard to the beginning and the end of 
a range of chords/songs and with regard to the song number. For an easy 
visual interpretation, preferably the combinations given in FIG. 12 are 
used in the present installation. The combination ENR is used for 
programming a song of any length. With a view to the simple programming 
and reading by the player, the song number should be represented 
preferably in bed-form (binary coded decimal) with the most significant 
cypher in front. In order not to mix up an 0 in the song number with the 
codeword with the binary value 0, b.sub.5 and/or b.sub.6 of a cypher of 
the song number should be given the logical value "1". 
The cards may have any length, that is they may comprise any number of 
codewords, because the range of chords and additional information of a 
song may be spread on several cards and several cards may consecutively be 
recorded in the memory. For the reading by the reading unit 300, a 
synchronisation track 201 may be made on the card (see FIG. 11). This, is 
not essential, however, since a relevant codeword has at least one logical 
"1", furthermore by using a narrow program card (FIG. 9) a good guiding of 
the card is possible and the signals emanating from the scanners may be 
integrated before a decision is taken as to which of the possible 
codewords is actually read. However, in case a broad card is used, for 
instance as shown in FIG. 10, such a synchronization track 201 is 
advisable. FIG. 11 shows a possible solution for a program card 200 if the 
information concerning the chords is not coded. Such a card is more 
particularly suitable for those players who perfer it for reasons of 
simplicity of the programming, speed of the programming and the number of 
cards to be programmed and who are less interested in the size of the card 
and the possible number of chords to be programmed on the card. In this 
connection, it is preferable to represent the song number in decimal form. 
The control symbols shown on the card according to FIG. 11 have the 
signification indicated in FIG. 13. 
It is to be observed that the card according to FIG. 11 presents the 
possibility of indicating the chord tones by means of symbols of the organ 
keys indicated on the card, or according to the klavarskribo system or the 
customary music notation, as explained with reference to FIG. 5 which is a 
convenience especially for the beginner. 
Because preferably a microprocessor is used, the control program can be 
made suitable in a simple manner for reading of information of the cards 
according to FIGS. 9 to 11 mentioned as examples. By means of a selector 
switch or a marking by means of the wiring, the control program can be 
given information as to which type of card 200 c.q. card reader 300 is 
used. By making the card readers 300 exchangeable, the wishes of a 
potential user can be met to a high degree. 
The following is an explanation of the embodiment according to FIG. 7. This 
is not based upon a conventional component arrangement but referenced on a 
so-called flow chart which is shown in FIG. 14. By means of the many 
commercial components, many embodiments may be made which only differ in 
their physical apearance. 
In the flow chart according to FIG. 14, only one block is shown as a 
subroutine; other blocks, combinations or parts of blocks in this diagram 
may also be programmed as subroutines. 
In the flow chart according to FIG. 14, only one block is shown as a 
subroutine; other blocks, combinations or parts of blocks in this diagram 
may also be programmed as subroutines. 
The current diagram according to FIG. 14 comprises two important portions, 
namely a portion which is connected with the recording of a program card 
and a portion for reading out the memory during the playing of the 
electronic organ. For this reading there are two possibilities: 
(a) first erase the entire memory and then record one or more songs; 
(b) exchange one or more songs recorded in the memory for one or more new 
songs and maintain the rest. With the indications in FIG. 14 a relation is 
established with the signal buses in FIG. 7. 
If by means of the control panel it is indicated whether a card has to be 
red, a test is carried out with regard to the kind of the card 200 used or 
the card reader 300. Then the drive motor in the reading unit 300 is 
started to move the card 200 along a scanner in the unit 300. Transport of 
the card by handdrive is also possible. Subsequently or before, the user 
should indicate in what manner the input into the memory 500 should take 
place. This is dependent on the information whether the card 200 refers to 
the first song to be introduced, on the information whether the song is a 
song to be added, or on the information whether the song should be 
exchanged for another song already stored in the memory 500. More 
particularly, so far as the latter aspect is concerned, the program is 
such that optimal use is made of the memory 500 and that, if needs be, a 
new arrangement of the memory information is carried out. Moreover, with a 
view to optimal use of the memory 500, the card information is put into 
the memory in a coded form, namely according to FIG. 12. A code-word with 
the binary 0 value recorded on the card 200 is not read in the memory. 
After the END symbol on the card has been read, or a suitable instruction 
has been given by means of the keyboard 100 via bus 190, the motor in the 
reading unit 300 is stopped and the reading procedure is diverted from. 
If the organ 600 is going to be played and instructions thereto are given 
to the control unit 400 from the panel 100 via bus 190, the memory can be 
read for supplying the programmed cords to the electronic organ 600. For 
this purpose, the song number and the bar number in that song should be 
recorded. If a number of songs is to be played consecutively, the 
respective numbers may be put into and stored in a register, for instance 
a portion of memory 500, for being reread in sequence. If, with respect to 
the contents of the memory, "impossible" numbers are indicated, this is 
signalled and new numbers have to be given. At the beginning of the 
playing, an indicator is put into the position which belongs to the memory 
location with the right numbers referred to above. If the word indicated 
by the indicator refers to the END symbol, a prefixed waiting time is 
taken into consideration before a range of chords of a song can be read 
from the memory. After termination of a song this waiting time is used for 
continuing automatically with a following song, the player being given the 
liberty to extend the finale of the first section according to his own 
fancy between the two plays without the chords of the following song being 
generated thereby. If during the playing the word indicated refers to the 
Start-symbol, the ENR-symbol (end of song), or a not-used, i.e. 
impossible, word (see FIG. 9), the further handling is as though an 
END-symbol is concerned. 
If the word read from the memory 500 refers to a chord, it is converted 
from the code according to FIG. 8 (6 bit) under which it was stored in the 
memory 500, into the code which can be used by the electronic organ as 
shown in FIG. 13 (16 bit). Upon receipt of a pulse from the electronic 
organ 600 via line 680, the respective chord signal is then supplied to 
the electronic organ 600 and used. After the pulse on line 680 has 
terminated, the indicator is then increased by one, and the reading of the 
new memory location, the testing thereon and the supply of the decoded 
information to the electronic organ 600 is then carried out, and 
subsequently the indicator is then again increased by one, etc. As long as 
no pulse is received, it is tested whether a new instruction, such as a 
instruction, is or has been given with panel 100 via line 190. If this is 
the case, the playing is ended and the respective activity is undertaken 
according to the new instruction. 
The embodiment of FIG. 8 differs from that of FIG. 7 in that there is no 
need for certain repetitive portions of a piece of music to reappear in a 
program card 200 or in the memory 500. Moreover, according to the 
preferred embodiment of FIG. 8, it is possible to let ranges of chords 
play programmed ranges of melodies or one of both ranges. Furthermore, as 
regards ranges of melody-tones, the possibility is included to give one 
time's rest, to use half tones, to retain a tone till the next time of the 
following bar and to choose a tone from the tones of four chords. 
FIG. 15 is a possible program card for the embodiment of FIG. 8 to be coded 
according to FIG. 17. 
FIG. 16 is a card easy in operation for the user, which is to be programmed 
in accordance with FIG. 18. The remarks made with regard to the use of the 
card according to FIG. 11 instead of those according to FIGS. 9 and 10 
also apply to the use of the card of FIG. 16, instead of that of FIG. 15. 
The code according to FIG. 17 will also be used for the storage in the 
memory, since the memory is thereby utilized better than when using the 
code according to FIG. 18 and, with a view to the choice and the price of 
available components, such as memories and microprocessors, it is 
desirable to use words of maximum 8 bits. 
The preferred embodiment according to FIG. 8 will be explained with 
reference to the flow chart formed by FIGS. 19a and 19b together. Above 
the point indicated by the index in FIG. 19a will be the same portion as 
that which is located above the point indicated by index in FIG. 14. For 
the sake of simplicity in the illustration that portion has been left out 
in FIG. 19a. 
The starting point is that at each first count of a bar the electronic 
organ 600 gives a pulse via lines 680 to the control unit 400 for the 
purpose of generating chords, and moreover, at each count of a bar, 
supplies a pulse to the control unit 400 via line 690 for the purpose of 
generating melody tones. The pulses generated by the organ are such or are 
processed in such a manner that the duration of a pulse on line 680 
includes a pulse on line 690. FIG. 20 gives an illustration of the 
foregoing for a quadruple time. 
If during the playing a word read from the memory refers to the START 
symbol, the END symbol, a cypher of a song number or a codeword not used, 
i.e. an "impossible" word, the further handling is as though the word 
refers to an END symbol. In other words, for reasons explained in 
connection with the embodiment of FIG. 7, a preset time is waited before 
the next song can be commenced with. If the word refers to a jump (b.sub.4 
. . . 1 =1111 in FIG. 17), a jump is made to the foregoing flag in the 
song, provided at least the number of repetitions do not exceed thereby 
the number indicated in the jump symbol. If there is a pulse on both line 
680 and line 690, the two consecutive memory locations are read, the first 
of which concerns the first chord not yet performed. If the second memory 
location again concerns a chord, a jump back to the beginning of the 
procedure (beginning of this paragraph) is made after termination of the 
pulse on line 680. If the said second memory location concerns a tone then 
it is supplied at the same time--anyhow apparently for the user--with the 
chord to the electronic organ 600. After termination of the longest pulse 
in a count, the beginning of the loop is returned to. If a pulse is 
received by the control unit 500 via line 690 but if there is no pulse via 
line 680, the memory location is decoded and supplied to the electronic 
organ. The output is made to correspond with the programmed demands such 
as in connection with half and full tones, rest count and holding a tone. 
For the half duration of a tone, the time between two pulses on line 690 
should be measured and divided by two. In an interval between two counts 
thus found, a half tone may be performed, if desired. The holding of a 
tone does not last longer than till the output of a following tone. After 
the longest pulse has passed, the beginning of the loop (i.e. the 
beginning of this paragraph) is returned to. 
It is observed that the present invention may be carried out using discrete 
gates, flip-flops, counters, etc., for which taking into consideration the 
large choice of components available, many embodiments are possible. 
However, in connection with the complexity, the development of heat, the 
sensitivity to disturbances and the physical size of an embodiment with 
discrete components, it is, however, advisable to use a microprocessor, 
taking into consideration the present state of the art.