PAL/GAL macrocell placement Within a traditional PAL or GAL architecture, where are the macrocells located relative to the programmable arrays?

Introduction / Context:
Macrocells provide output-specific features such as optional output registers, tri-state control, polarity options, and feedback paths. Knowing where they sit in the signal path helps you understand timing and feedback routing when implementing counters, state machines, or wide decoders in PAL/GAL devices.

Given Data / Assumptions:

• PAL/GAL devices have a programmable AND array feeding a fixed OR array.
• Outputs often pass through macrocells offering register/combination selection and feedback.
• Inputs feed the AND array independently.

Concept / Approach:
Signals flow from inputs → programmable AND → fixed OR → macrocell → output pin (with possible feedback from macrocell to the AND array). Thus, the macrocell belongs at the output side, where it can condition, register, or invert the signal and control I/O behaviors such as tri-stating on bus interfaces.

Step-by-Step Solution:

Verification / Alternative check:
Typical PAL/GAL block diagrams show macrocells physically and logically adjacent to output pins, confirming placement at the output terminals.

Why Other Options Are Wrong:

• after the programmable AND arrays: Incomplete; must include the OR array and specifically the output side.
• ahead of the programmable AND arrays / at input terminals: Opposite of the actual flow.

Common Pitfalls:
Misunderstanding feedback timing from macrocell outputs back into the AND plane, which affects setup/hold for registered implementations.

Final Answer:
at the output terminals