I'll provide you with a complete Verilog-based traffic light controller implementation suitable for Cadence simulation, including the main module, testbench, and SDC constraints file.
traffic_light_controller.v
Key Features of the Implementation:
Traffic Light Controller (traffic_light_controller.v):
- State Machine: 6 states including emergency and all-red transition
- Multiple Modes: Normal, Night, Rush Hour, and Manual modes
- Safety Features: All-red transition state prevents conflicts
- Emergency Override: Immediate response to emergency signals
- Configurable Timing: Easy to modify timing parameters
Testbench (traffic_light_tb.v):
- Comprehensive Testing: Tests all modes and edge cases
- Safety Monitoring: Detects illegal states (both directions green)
- Waveform Generation: Creates VCD file for Cadence viewing
- Performance Monitoring: Tracks state changes and timing
- Detailed Logging: Formatted output for easy debugging
SDC File (traffic_light.sdc):
- Clock Constraints: 100MHz system clock with uncertainty
- I/O Timing: Input/output delays for external interface
- Design Rules: Maximum transition, fanout, and capacitance
- Power Considerations: Switching activity for power analysis
- Path Grouping: Organized for timing report analysis
Usage in Cadence:
- Simulation: Use
ncverilog or xcelium to run the testbench - Synthesis: Use
genus with the SDC file for timing-driven synthesis - Waveform Viewing: Use
simvision to view the generated VCD file - Static Timing Analysis: Use
tempus with the SDC constraints
The design is scalable and can be easily modified for different timing requirements or additional features like pedestrian crossing signals.