1. A method of performing a Boolean OR operation on a function of two independent variables, one of said variables being stored in a first digital storage device which will also contain the result of said Boolean OR operation, the other of said variables being stored in a second digital storage device, the method comprising: writing a digital "1" into said first digital storage device when the contents of said second digital storage device is a digital "1" without reading the contents of said first digital storage device; and inhibiting a write cycle of said first digital storage device when the contents of said second digital storage device is a digital "0".