Question

Match List - I with List - II.

List - I	List - II
A. Address bus B. Data bus C. Control bus D. Tristate logic	I. Carries read/write signals, timing signals, and interrupt signals II. A three-state output that can be high, low, or high-impedance III. Unidirectional lines used by CPU to point to a memory location or I/O device IV. Bidirectional lines used for transferring data between CPU and memory

• A. A-I, B-II, C-III, D-IV
• B. A-IV, B-III, C-II, D-I
• C. A-III, B-IV, C-I, D-II
• D. A-II, B-I, C-IV, D-III

Hint:

Bus functions:
• Address bus \(\rightarrow\) Carries address
• Data bus \(\rightarrow\) Carries data
• Control bus \(\rightarrow\) Carries control signals
• Tristate logic \(\rightarrow\) High, Low, High-Z states

Answer 1

The Correct Option is C

Concept: A microprocessor system communicates internally using three important buses:
• Address bus
• Data bus
• Control bus In addition, tristate logic is used in digital systems to avoid bus conflicts and permit multiple devices to share common communication lines.

Step 1: Match Address Bus. Address bus is responsible for specifying: \[ \text{Which memory location or I/O device is to be accessed} \] Important properties:
• Unidirectional
• Generated by CPU
• Carries addresses only Hence: \[ \text{Address bus} \rightarrow \text{Unidirectional lines used by CPU to point to a memory location or I/O device} \] Thus: \[ A \rightarrow III \]

Step 2: Match Data Bus. Data bus transfers: \[ \text{Actual data between CPU and memory/peripherals} \] Properties:
• Bidirectional
• Carries binary information Therefore: \[ \text{Data bus} \rightarrow \text{Bidirectional lines used for transferring data} \] Thus: \[ B \rightarrow IV \]

Step 3: Match Control Bus. Control bus carries:
• Read signal
• Write signal
• Timing signals
• Interrupt signals Hence: \[ C \rightarrow I \]

Step 4: Match Tristate Logic. Tristate logic can exist in three states: \[ 0,\ 1,\ \text{High impedance} \] The high impedance state disconnects the output electrically from the bus. Thus: \[ D \rightarrow II \]

Step 5: Write final matching. Therefore: \[ A-III,\ B-IV,\ C-I,\ D-II \]

Step 6: Write the final answer. Hence the correct option is: \[ \boxed{(C)\ A-III,\ B-IV,\ C-I,\ D-II} \]