Rhythm generator for electronic organ

Abstract

An electronic rhythm generator particularly suited for incorporation in an electronic organ. A counter, clocked by time sequential rhythm clock pulses, produces a cyclically repeating series of counts comprising binary words having a most significant bit and a plurality of least significant bits which address a read only memory having a plurality of preprogrammed rhythm patterns stored therein. The memory comprises two sections in which a first set and a second set of rhythm patterns respectively are stored and which is programmed such that one of the sections is enabled only when the most significant bit of the counter output is a logic 1 and the other section is enabled only when the most significant bit is a logic 0. The memory responds to a series of sequential enabling signals on certain of its address lines corresponding to the respective least significant bits of the binary words to produce at its output rhythm signals in the rhythm patterns selected within its enabled section. Player actuated override control means are provided for selectively holding the most significant bit of the counter output at either of the aforementioned logic levels so as to cause one or the other of the selected rhythms to repeat for each cycle of the least significant bit portion of the binary word. If the most significant bit of the count is permitted to change states every half cycle of the total count sequence, the rhythm pattern will alternate between the two selected rhythms.