Traffic light controller state machine template

States in this state machine

• Red
• Red Amber
• Green
• Amber
• Pedestrian Wait
• Pedestrian crossing
• Flashing Amber
• Off

How to use this state diagram template

1. Click Open in the editor. The state diagram opens on a new page in FlowDiagram — nothing is uploaded and there is no sign-up.
2. Rename, add or delete shapes and drag them where you want; connectors stay attached as things move.
3. Drop in vendor logos from the library — 1,160 of them, including every AWS, Azure and Google Cloud service icon — or restyle it with the colour and theme controls.
4. Prefer text? Edit the Mermaid source below and paste it in through ☰ → Import diagram (see the Mermaid editor); it imports as an editable diagram.
5. Export to PNG, SVG or PDF, or press Ctrl+L for a link that carries the whole diagram.

Mermaid source

The whole template is the text below. Paste it into FlowDiagram, keep it in Git next to the code it describes, or hand it to an AI assistant to extend.

stateDiagram-v2
  [*] --> Red
  Red --> RedAmber : timer 30s
  RedAmber --> Green : timer 2s
  Green --> Amber : timer 25s
  Green --> PedestrianWait : button pressed
  PedestrianWait --> Amber : min green elapsed
  Amber --> Red : timer 3s
  state "Pedestrian crossing" as Walk
  Red --> Walk : pedestrian request queued
  Walk --> Red : walk phase ended
  Red --> FlashingAmber : controller fault
  Green --> FlashingAmber : controller fault
  FlashingAmber --> Red : fault cleared
  FlashingAmber --> Off : power down
  Off --> [*]

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