The read only form comes with a counter register. This register is a time saving device. When jumping between values, a quick comparison tells whether to move up for down the tape (it is assumed the labels are in order). For the computer described, a read only associative list holds the program listing. Each label is the name of a function, and the counter register holds the name of the currently executed function. A second register holds the current line number and acts the the program counter. |