The bottle that was counted twice

What the checks test

1. T1Only completed bottles that leave the station increase Accepted.
2. T2Jam/Hold wins over completion and needs Resume after clearing.
3. T3A lost unfinished bottle increases Rejected exactly once; active Reset cannot erase totals.

The checks run 7 tests on the machine, scan by scan: Resume cannot beat an active jam; Stop can end Held; Count departures, not filled scans; complete three bottles; Jam beats completion and clearing it cannot resume; A bottle lost while held is rejected exactly once; A completed bottle leaving during Hold is counted on recovery; Stop wins; fresh Start is required after permission returns; Reset during filling cannot discard the bottle or totals.

Where you’d find this

While clearing a jam on a bottling line, an operator removes a half-filled bottle. The controller must remember what was cut short.

Counting a half-filled bottle as good sends short bottles down the line. A restart while someone clears the jam can move the line without warning.

How it should behave

States and commands

0 = idle, 10 = feed, 20 = fill, 30 = held, 40 = release, 50 = complete. ConveyorOn is ON only in 10/40. FillValve is ON only in 20 with BottlePresent. Done is TRUE only in 50. Ordinary phase changes may use the complete previous or new command set on their entry scan, then must settle. Stop, permission loss, Jam and Hold remove both commands immediately. Never fill without BottlePresent.

One transition

A fresh Start edge enters 10 only with Permit, no Stop, no Jam and no Hold. In 10, BottlePresent enters 20. In 20, Volume >= 80 enters 40. Process only one phase transition per scan. A bottle must remain present to complete.

Priority and hold

Stop or lost Permit enters 0 immediately. Jam/Hold has priority over bottle loss and completion in active phases, enters 30 and remembers SavedPhase. Clearing the cause does nothing until Resume with Jam/Hold clear. Resume enters the saved phase for one scan before processing that phase again.

Accepted and rejected

In 40, BottlePresent FALSE increases Accepted exactly once and returns to 10; the third accepted departure enters 50. A bottle lost in fill or held-fill increases Rejected once. Held-fill then remembers feed and waits for Resume. A completed bottle removed during held-release is counted when the resumed release phase next runs.

Reset / restart

Start must be released and pressed again after Stop/Permit loss. Reset works only in 0/50 with Start released, no Stop and Permit TRUE: clear Accepted and Rejected and remain idle. Ignore Reset in active phases. Completion cannot be restarted with Start alone.

Use Run and Start. Try Jam at 80% and clear it without Resume: both commands stay OFF. Then use Inputs to hold BottlePresent FALSE while held during an unfinished fill. Rejected rises once, never Accepted. Replay each failed test to compare the saved phase and bottle totals.