CodiodeCodiode
Home
Problem Solving
Skill Tracks
My Assignments
Contests
Leaderboard
Community
Settings
Codiode/Problems/Sequential Logic

PAL Fixed OR Plane Limitation

MediumLogic CircuitAnalyze

Programmable Array Logic devices reduce cost and maximize speed by pairing a programmable AND plane with a fixed OR plane. Designers must map their boolean functions onto a rigid physical architecture where the number of product terms per output is hardcoded during manufacturing.

The target hardware is a basic PAL where each output pin is driven by a single OR gate connected to exactly three programmable AND gates. The logic function required for the system is Y = A'BC'D + AB'C'D + ABCD' + A'B'CD.

Determine how the architectural limitations of the PAL restrict the implementation of this function and identify valid engineering workarounds.

Constraints

  • The PAL architecture provides exactly 3 AND gates hardwired to each OR gate.
  • The target function Y is provided in standard sum-of-products form.
  • No internal programmable feedback paths are available unless explicitly stated.

Topics

Combinational LogicProgrammable LogicHardware ConstraintsPALPLA

Solve this problem

Place the gates, wire them up and watch the signals settle. Every submission runs on the same simulation engine that grades it.

This problem is part of Codiode Pro. The statement above is free to read.

Sign in to solveSee what Pro unlocks

The circuit builder and code editor need a desktop screen. On a phone, read the problem here and open it on a laptop to solve.

Related problems

  • 3-bit Ripple Counter from Toggle Flip-FlopsEasy
  • D Latch from a 2:1 MUXEasy
  • 2-bit Ring CounterEasy
  • T Flip-Flop from a D Flip-FlopEasy
  • Handshake Deadlock Due to Early ResetHard
  • Reconvergence of Individually Synchronized BitsHard
  • Debug: Asynchronous Clear GlitchHard
  • Clock Gate Enable Crossing DomainsHard

Browse all problems · Learning tracks