As we shall see, the ALU is the heart of the computer and microprocessor architectures. By feeding the Select inputs with a series of mode words, a program of operations can be performed by the ALU. Such operation codes are stored in an external memory, and are accessed sequentially by the computer’s control circuits. Sequences […]
There are many bistable implementations. For example, replacing the NOR gates by NAND gives a RS latch, where the inputs are active on a logic 0. The circuit illustrated in Fig. 2.14 shows such a latch used to de-bounce a mechanical switch. Manual switches are frequently used as inputs to logic circuits. However, most metallic […]