Микроконтроллеры

только как R/W-ячейка памяти. никаких функций контроля и управления он не несет (scratch register - рабочий регистр) 

scratch 1. (From "scratchpad") Describes a data structure or recording medium attached to a machine for testing or temporary-use purposes; one that can be scribbled on without loss. Usually in the combining forms "scratch memory", "scratch register", "scratch disk", "scratch tape", "scratch volume".

cheers