State Diagram Updated 4/16/2026

ATM State Diagram for Card, PIN, Withdrawal, and Error Handling

This state diagram is used to model how an ATM moves from power on and idle through card reading, PIN entry, menu selection, amount entry, processing, cash dispensing, receipt printing, card ejection, card retention after three failed PIN attempts, and out-of-service recovery. It helps clarify valid transitions, exception handling, and session outcomes for banking software teams, QA testers, ATM product managers, and operations staff.

State DiagramATMBanking WorkflowPIN VerificationCash Withdrawal
13 nodes 22 connections