Digital I/O fundamentals: In general-purpose digital interfaces, a port can be configured for which directions of data flow?

Introduction / Context:
Microcontrollers and microprocessor systems expose ports to interact with external circuits. Ports can be designed or configured to accept data, drive data, or do both depending on the application and hardware capabilities.

Given Data / Assumptions:

• General-purpose I/O (GPIO) concept applies.
• Hardware may support direction control via configuration registers.
• Some peripherals use dedicated input-only or output-only pins.

Concept / Approach:
An I/O port is an interface abstraction. Depending on design, it may be input-only (e.g., status sensing), output-only (e.g., LED drive), or bidirectional (e.g., data bus lines, GPIO pins). Many devices allow run-time direction control for flexibility.

Step-by-Step Solution:
Identify port types: input, output, bidirectional.Match to use cases: inputs read sensors; outputs drive actuators; bidirectional lines share roles (often with tri-state control).Recognize configuration: direction registers/tri-state buffers enable dynamic role changes.Therefore, all three are possible roles for ports.

Verification / Alternative check:
Examine datasheets: GPIO pins commonly have direction bits; parallel ports support input/output modes; buses use bidirectional signals with enable control.

Why Other Options Are Wrong:
Restricting to only one direction ignores the flexibility of modern port designs.

Common Pitfalls:
Forgetting to handle contention on bidirectional lines; proper use of direction control and tri-state is essential to avoid bus conflicts.

Final Answer:
all the above