Digital systems – Definition of a transceiver What is a transceiver circuit in the context of shared digital data buses?

Introduction / Context:Transceivers are widely used on shared data buses to allow bidirectional data movement while preventing contention. Understanding their role is essential for bus-oriented microprocessor and FPGA designs.

Given Data / Assumptions:

• A single signal path may need to carry data in either direction at different times.
• Control signals enable or disable driving the bus to avoid conflicts.

Concept / Approach:Transceiver = transmitter + receiver in one device. It typically has direction control (DIR) and output enable (OE). When DIR selects A→B, the device drives from side A to side B; when toggled, it drives from B→A. OE places outputs in high-impedance when disabled, isolating the device from the bus.

Step-by-Step Solution:

Verification / Alternative check:Common TTL/CMOS parts such as 74xx245 are marketed as 'octal bus transceivers' and include DIR and OE pins; their datasheets confirm bidirectional buffering as the primary function.

Why Other Options Are Wrong:

• a buffer that transfers data from input to output: One-direction only.
• a buffer that transfers data from output to input: Also one-direction only (reversed).
• blank option: Not applicable.

Common Pitfalls:

• Confusing a simple buffer/line driver (unidirectional) with a transceiver (bidirectional).
• Forgetting that high-impedance control is vital to prevent bus contention.

Final Answer:a buffer that can operate in both directions