General design procedure for combinational logic
4 – Combinational Logic Design Examples
1. Understand the problem
- what is the circuit supposed to do?
- write down inputs (data, control) and outputs
- draw block diagram or other picture
2. Formulate the problem using a suitable design representation
- truth table or waveform diagram are typical
- may require encoding of symbolic inputs and outputs
3. Choose implementation target
- ROM, PAL, PLA
- mux, decoder and OR-gate
- discrete gates
4. Follow implementation procedure
- K-maps for two-level, multi-level
- design tools and hardware description language (e.g., ABEL)