Matching Bus Components and Logic

This question requires matching different types of computer buses and a logic characteristic with their respective functions or definitions.

Address Bus Matching

The Address bus is used by the CPU to specify the location in memory or the I/O device it intends to communicate with. These lines are unidirectional, meaning they carry information only from the CPU. Therefore, the Address bus matches with characteristic III.

Data Bus Matching

The Data bus is responsible for the actual transfer of data between the CPU, memory, and peripherals. This communication needs to be in both directions (CPU to memory/peripheral and vice versa), making the Data bus bidirectional. Thus, the Data bus matches with characteristic IV.

Control Bus Matching

The Control bus carries various control and timing signals that manage the operation of the system. These signals include read/write commands, clock signals, interrupt requests, and status signals. Therefore, the Control bus matches with characteristic I.

Tristate Logic Matching

Tristate logic describes an output that can exist in one of three states: a logic high level, a logic low level, or a high-impedance state. This high-impedance state effectively disconnects the output, preventing it from affecting the bus when not actively transmitting data. This characteristic matches with definition II.

Final Correct Match

Based on the analysis:

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

The correct combination is A-III, B-IV, C-I, D-II.