Flushing Valve Sequence

Briefing

A pipeline flushing system opens valves and runs a pump in a timed sequence to purge a pipe section. The sequence is: open inlet valve (5s), start pump (10s), open outlet valve + close inlet, drain through drain valve (3s), then close all. Each step uses a timed transition. ABORT immediately drops all outputs. An internal FAULT latches if the sequence takes too long.

Objectives

• START_PB begins the flush sequence from IDLE
• Sequence: VALVE_INLET open 5s → PUMP_RUN 10s → VALVE_OUTLET open + VALVE_INLET close → VALVE_DRAIN 3s → all closed
• SEQ_COMPLETE_LAMP lights for 2s when sequence finishes successfully
• ABORT_PB or STOP_PB at any time drops all outputs and returns to IDLE
• FAULT_LAMP latches if sequence does not complete within 30s

I/O Table

Your program will be tested against:

All test cases run automatically when you submit. Assertions are hidden until you pass.

1. #1VALVE_INLET opens when START_PB pressed

   START_PB -> VALVE_INLET energises in step FILL

2. #2Pump runs after inlet step (5s)

   After 5s in FILL, PUMP_RUN energises

3. #3ABORT_PB drops all outputs immediately

   Mid-sequence abort clears all valves and pump

4. #4Full sequence completes and lights SEQ_COMPLETE_LAMP

   Run full sequence: FILL(5s)+PUMP(10s)+FLUSH(0s)+DRAIN(3s) -> SEQ_COMPLETE_LAMP