Traffic Lights Controller in VHDL
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The document describes a simple traffic light controller implemented as a state machine using a timer. It outlines a system for a 4-way junction where each traffic light is green for 20 seconds, followed by 5 seconds of yellow, while all other lights remain red. The process is continuous and follows a specific state diagram to manage transitions between light colors based on the timer's value.
Traffic Lights Controller in VHDL
- 1. Traffic Lights Controller By - Abhishek Jaisingh ( 14114002 ) A simple traffic light controller can be implemented by a state machine that has a state diagram such as the one shown in Figure. Its state progresses according the value of the timer used . When the value of timer reaches a specific value, the state of the system changes . A set of 4 traffic lights have been designed for a 4 – way junction as shown. The states are defined in terms of the output . Timer goes from 0 to 100 and then it is reset to 0. Each light is programmed to run as follows: 1. It is GREEN for 20 s. 2. Then it remains YELLOW for 5s. During this time all other lights remain RED. This process is continued for all the lights successively.
- 2. Finite StateMachine ( Moore Machine ) State Diagram S0 S1 S2 S3 S4 S5 S6 S7
- 3. State Table Time (input) Current State Next State Output The color in output represents output light. time = 0 after time becomes 100.
- 4. Code