As an example, the transistor-transistor logic (TTL) 7408 chip contains four, two-input AND gates in one integrated circuit (IC) package. These gates and other types on separate ICs can be wired ...

Fig. 2. Ladder logic uses memory locations rather than hard-wired logic. For the program shown in Fig. 2, we took the relay logic’s ladder diagram from Fig. 1 and duplicated it with ladder logic — no ...