A harmony generator for an electronic organ and a method of generating harmony in an electronic organ

摘要

A harmony generator for an electronic organ and a method of generating harmony in an electronic organ are disclosed. The identity of played keys of the keyboard(s) is read into a storage device (58). The data contained in this storage device is then operated upon by a data processing device such as a microcomputer (50), so as to supplement the played note data with additional data designating "fill-in" notes which are to be sounded in addition to those actually played, based upon specified criteria. The data contained in the storage device, as supplemented, is then used to control the transmission of tone generator signals to the audio output system (170) of the organ. In a preferred embodiment of the invention, the criteria used to select fill-in notes cause notes corresponding to the nomenclatures of played notes of the accompaniment keyboard to be sounded as though played in the octave belowthe lowest note played on the solo keyboard. Other fill-in criteria are also contemplated. The invention is particularly suited to use in conjunction with an 8-bit or a 12-bit microprocessor. In the 12-bit embodiment, the 12-bit words which are used to manipulate the data into the storage device each correspond to a single octave of the keyboard. In the 8-bit embodiments, two words are necessary in order to specify each octave of data. The fill-in notes are generated by combining played accompaniment data with masks. The identity of these masks is based upon the nomenclature of the lowest played note of the solo keyboard. Depending on the available space in the memory of the microcomputer, these masks can be looked up in a table, or generated by a suitable algorithm. Fill-in notes can be generated simultaneously by more than one set of criteria, and the fill-in notes so produced can be separately voiced.