When dealing with data bus signals, understand that each operation like memory read, write, or op-code fetch corresponds to a unique status signal for the processor.
Step 1: Understanding the data bus status signals.
- Memory read corresponds to the signal (I) 0, 1, 1.
- Op-code fetch corresponds to the signal (II) 0, 1, 0.
- INTR acknowledge corresponds to the signal (III) 0, 0, 1.
- Memory write corresponds to the signal (IV) 1, 1, 1.