I need help in programming and some construction details of this keyboard. It has many of the features described in my US patents 9,159,307 B1. D818,456 S and D837,201 S.
Refer to the block diagram Figure One:
The microprocessor needs 37 input pins. The power circuit converts 120 AC to the DC necessary to power the microprocessor. The microprocessor receives inputs from the 10 by 12 key matrix, the instrument-select keys, the sustain pedal input, the octave up-down keys, the pressure sensors and the volume control. The pressure sensors can be disconnected with a switch if they are not needed for expression (attack and after-touch). The instrument sound set is accessed by the microprocessor, which outputs mono audio. There is a keyboard for each hand so the audio from each will result in feeds to a stereo sound system.
Refer to 10 by 12 key matrix: Figure Two:
The key switches are arranged in a checkerboard pattern with each key allotted a 3/4" by 3/4" space, 10 keys across by 12 keys deep. Going from right to left, the notes ascend in half-steps. Going up, the notes ascend in musical fourths. Middle C is 6 steps over and 5 steps up. The Octave Down button moves the whole keyboard down one octave. The Octave Up button moves the whole keyboard up one octave. The extent of the range is only one octave up and one octave down.
Refer to Figure 3.
The Volume control sets the initial volume. The 10 by 12 matrix board is mounted on a rigid plate that floats on its four corners on pressure sensors (like piezo plates) connected in series so that the addition of the four signals always registers the pressure put on a key anywhere on the board. This signal is used to register attack and after touch, adding to the basic volume setting. It can be switched off if these effects are not needed.
Refer to Instrument Set: Figure 4.
The 12 instrument select buttons are used to choose the instrument sound output by the keyboard. By holding down any note key and then repeatedly pressing one of the instrument category keys, you can cycle through the instrument sounds in that category and stop when you hear the desired sound. That sound will play then across the whole keyboard.
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