Electronic organ having microprocessor controlled rhythmic note pattern generation

An electronic keyboard musical instrument comprising:

• a first controllable tone generator means including a divider string for producing on an output of the divider string a selectable accompaniment tone,
• a second controllable tone generator means including a divider string for producing on an output of the divider string of said second controllable means a selectable bass tone,
• accompaniment note pattern generator means for controlling said first controllable means and said first divider means to automatically produce a rhythmic accompaniment pattern of a series of the accompaniment tones having respective selected frequencies,
• bass pattern generator means for controlling said second controllable means to automatically produce a rhythmic bass pattern of a series of the bass tones having respective selected frequencies, and
• means responsive to said accompaniment and bass pattern generator means when an accompaniment tone and a bass tone simultaneously selected, respectively, by the accompaniment and bass pattern generator means are of the same pitch and are octavely related for disabling one of said first and second controllable means and causing the other of said first and second controllable means to produce both of said octavely related tones on respective outputs of the divider string of said other controllable means.