Fault isolation scope: “Testing and troubleshooting only the address-decoding logic will not reveal problems with the memory chips themselves or their connections to the CPU buses.” Evaluate this statement.

Introduction / Context:
Address-decoding logic ensures that a given address range selects the correct memory device. However, a functioning decoder does not guarantee that the memory ICs or their data/address/control bus connections are healthy. Effective troubleshooting must consider all stages in the memory access path.

Given Data / Assumptions:

• We test only the decoder (e.g., chip-select generation).
• Memory devices and bus wiring are not tested by this decoder-only procedure.
• Goal: determine if decoder testing alone can expose all memory path faults.

Concept / Approach:
Decoder verification confirms that addresses map to the intended chip-select lines. But failures such as stuck data bits, broken address lines at the IC pins, timing violations, power/ground issues, or defective memory arrays will not be detected if only the decoder is exercised in isolation. Full memory testing requires actual reads/writes to the chips across the buses and validation of returned data patterns (e.g., walking ones/zeros, checkerboards, March tests).

Step-by-Step Solution:

Verification / Alternative check:
Practical diagnostics differentiate “select” faults (wrong chip selected) from “data integrity” faults (wrong values read/written). The latter require memory test patterns, not just decoder toggling.

Why Other Options Are Wrong:

• Incorrect: Implies decoder tests are sufficient, which is false.
• Ambiguous / ROM-only: The logic applies to RAM, ROM, and peripherals alike.

Common Pitfalls:
Assuming that seeing chip-select activity guarantees a healthy memory path; ignoring signal integrity, timing margins, or power anomalies that corrupt data independently of the decoder.

Final Answer:
Correct