FAILURE MAP
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FA-92266 / PLC ladder logic scan cycles / Open access

Free-running clock timer reports raw elapsed ticks after completion · case 01

The reported accumulated time keeps changing (and wraps) after the timer is done.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The output reports the raw modular elapsed value instead of capping at preset once done.

VERIFIED REPAIR

Report the preset once done.

Unsuccessful approach: Capping with min(elapsed, preset) still drops after the elapsed value wraps.

Case contract

Delay timer built on a 16-bit free-running clock register (ticks wrap from 65535 to 0). samples is a list of [enable, clock] read each scan. The first enabled scan captures the start tick; elapsed is (clock - start) modulo 65536. Done latches once elapsed >= preset and stays set while enabled even if the elapsed value later wraps. A disabled scan clears start and done. Return [done, elapsed capped at preset once done] per scan, [False, 0] when disabled.

Why this case matters

Ladder programs are executed as repeated scans; each defect here changes what a rung, timer, counter or data-table instruction reports on a particular scan, which is how commissioning and field faults are actually observed.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(preset, samples):
    start = None
    done = False
    out = []
    for enable, clock in samples:
        if not enable:
            start = None
            done = False
            out.append([False, 0])
            continue
        if start is None:
            start = clock
        elapsed = (clock - start) & 0xFFFF
        if elapsed >= preset:
            done = True
        out.append([done, elapsed])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: long enable past a full wrap',
   [1000, [[True, 100], [True, 30100], [True, 60100], [True, 24564], [True, 700]]],
   [[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]],
  ['regression: elapsed returns to zero',
   [5, [[True, 10], [True, 20], [True, 10], [True, 12]]],
   [[False, 0], [True, 5], [True, 5], [True, 5]]],
  ['control: clock wrap',
   [100, [[True, 65500], [True, 65530], [True, 40], [True, 64], [False, 70]]],
   [[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]],
  ['regression: enable after idle',
   [50, [[False, 0], [False, 400], [True, 900], [True, 930], [True, 960]]],
   [[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]],
  ['regression: scenario 1',
   [100,
    [[True, 53593],
     [True, 53635],
     [True, 10212],
     [False, 10250],
     [True, 24553],
     [True, 35364],
     [True, 35501],
     [True, 35591],
     [True, 65279],
     [True, 65379],
     [True, 65509]]],
   [[False, 0],
    [False, 42],
    [True, 100],
    [False, 0],
    [False, 0],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100]]],
  ['regression: scenario 2',
   [100,
    [[True, 17304],
     [True, 20531],
     [True, 27559],
     [False, 57396],
     [True, 19489],
     [True, 46000],
     [True, 46035],
     [True, 46209],
     [True, 5526]]],
   [[False, 0],
    [True, 100],
    [True, 100],
    [False, 0],
    [False, 0],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100]]],
  ['control: scenario 3',
   [40000,
    [[True, 42783],
     [False, 4625],
     [True, 4670],
     [True, 8857],
     [False, 15422],
     [False, 15500],
     [True, 15560],
     [True, 27335],
     [True, 27471]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 4187],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 11775],
    [False, 11911]]],
  ['regression: scenario 4',
   [100,
    [[True, 2607],
     [True, 18576],
     [True, 18609],
     [True, 18619],
     [True, 45272],
     [True, 45282],
     [True, 55824],
     [False, 61503]]],
   [[False, 0], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [False, 0]]]],
 [['regression: elapsed returns to zero',
   [5, [[True, 10], [True, 20], [True, 10], [True, 12]]],
   [[False, 0], [True, 5], [True, 5], [True, 5]]],
  ['regression: long enable past a full wrap',
   [1000, [[True, 100], [True, 30100], [True, 60100], [True, 24564], [True, 700]]],
   [[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]],
  ['control: clock wrap',
   [100, [[True, 65500], [True, 65530], [True, 40], [True, 64], [False, 70]]],
   [[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]],
  ['regression: enable after idle',
   [50, [[False, 0], [False, 400], [True, 900], [True, 930], [True, 960]]],
   [[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]],
  ['regression: scenario 1',
   [1000,
    [[False, 39404],
     [False, 39599],
     [True, 39752],
     [True, 39914],
     [False, 49270],
     [True, 53547],
     [True, 53700],
     [True, 4426]]],
   [[False, 0], [False, 0], [False, 0], [False, 162], [False, 0], [False, 0], [False, 153], [True, 1000]]],
  ['regression: scenario 2',
   [5,
    [[True, 40525],
     [True, 40666],
     [True, 40725],
     [True, 58227],
     [True, 18319],
     [False, 25775],
     [True, 25797],
     [True, 25799]]],
   [[False, 0], [True, 5], [True, 5], [True, 5], [True, 5], [False, 0], [False, 0], [False, 2]]],
  ['regression: scenario 3',
   [5,
    [[False, 30258],
     [True, 30296],
     [True, 45510],
     [True, 2343],
     [True, 12538],
     [True, 12596],
     [False, 12635],
     [True, 37410],
     [True, 53676],
     [True, 10497],
     [True, 10628],
     [False, 10824],
     [True, 27527],
     [True, 55148]]],
   [[False, 0],
    [False, 0],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [False, 0],
    [False, 0],
    [True, 5],
    [True, 5],
    [True, 5],
    [False, 0],
    [False, 0],
    [True, 5]]],
  ['control: scenario 4',
   [65535,
    [[True, 43066],
     [True, 60153],
     [False, 2292],
     [True, 2392],
     [True, 12076],
     [False, 28626],
     [False, 28693],
     [False, 45850],
     [True, 5636]]],
   [[False, 0],
    [False, 17087],
    [False, 0],
    [False, 0],
    [False, 9684],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0]]]],
 [['regression: enable after idle',
   [50, [[False, 0], [False, 400], [True, 900], [True, 930], [True, 960]]],
   [[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]],
  ['regression: scenario 2',
   [40000,
    [[True, 54821],
     [True, 18035],
     [True, 32212],
     [True, 38340],
     [True, 38521],
     [True, 38565],
     [True, 38691],
     [True, 52834],
     [True, 6573],
     [False, 6717],
     [True, 13602]]],
   [[False, 0],
    [False, 28750],
    [True, 40000],
    [True, 40000],
    [True, 40000],
    [True, 40000],
    [True, 40000],
    [True, 40000],
    [True, 40000],
    [False, 0],
    [False, 0]]],
  ['control: clock wrap',
   [100, [[True, 65500], [True, 65530], [True, 40], [True, 64], [False, 70]]],
   [[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]],
  ['regression: long enable past a full wrap',
   [1000, [[True, 100], [True, 30100], [True, 60100], [True, 24564], [True, 700]]],
   [[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]],
  ['regression: elapsed returns to zero',
   [5, [[True, 10], [True, 20], [True, 10], [True, 12]]],
   [[False, 0], [True, 5], [True, 5], [True, 5]]],
  ['regression: scenario 1',
   [100,
    [[False, 22859],
     [True, 23009],
     [True, 46893],
     [True, 47082],
     [True, 47173],
     [True, 47274],
     [False, 47358],
     [True, 47448],
     [True, 54303],
     [True, 54477],
     [False, 54574]]],
   [[False, 0],
    [False, 0],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [False, 0],
    [False, 0],
    [True, 100],
    [True, 100],
    [False, 0]]],
  ['regression: scenario 3',
   [5,
    [[False, 23870],
     [True, 46782],
     [True, 46917],
     [True, 46976],
     [True, 56255],
     [True, 61627],
     [True, 1767],
     [True, 1874]]],
   [[False, 0], [False, 0], [True, 5], [True, 5], [True, 5], [True, 5], [True, 5], [True, 5]]],
  ['regression: scenario 4',
   [5,
    [[True, 25219],
     [True, 25303],
     [True, 25491],
     [True, 33180],
     [True, 33370],
     [True, 34085],
     [True, 35832],
     [True, 46392],
     [True, 48652],
     [True, 48709],
     [True, 6073],
     [True, 6100]]],
   [[False, 0],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5]]]],
 [['regression: scenario 2',
   [1000,
    [[False, 46148],
     [True, 57365],
     [False, 57416],
     [True, 57439],
     [True, 57613],
     [True, 57776],
     [True, 61872],
     [True, 62038],
     [True, 9532],
     [True, 32841],
     [True, 32973]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 174],
    [False, 337],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000]]],
  ['regression: long enable past a full wrap',
   [1000, [[True, 100], [True, 30100], [True, 60100], [True, 24564], [True, 700]]],
   [[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]],
  ['control: clock wrap',
   [100, [[True, 65500], [True, 65530], [True, 40], [True, 64], [False, 70]]],
   [[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]],
  ['regression: elapsed returns to zero',
   [5, [[True, 10], [True, 20], [True, 10], [True, 12]]],
   [[False, 0], [True, 5], [True, 5], [True, 5]]],
  ['regression: enable after idle',
   [50, [[False, 0], [False, 400], [True, 900], [True, 930], [True, 960]]],
   [[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]],
  ['control: scenario 1',
   [65535,
    [[False, 3784],
     [False, 8211],
     [False, 33966],
     [True, 50163],
     [True, 63009],
     [False, 63184],
     [True, 63243],
     [True, 63325]]],
   [[False, 0], [False, 0], [False, 0], [False, 0], [False, 12846], [False, 0], [False, 0], [False, 82]]],
  ['control: scenario 3',
   [65535,
    [[False, 15447],
     [True, 18837],
     [False, 18898],
     [True, 19006],
     [False, 33164],
     [True, 33164],
     [True, 41175],
     [True, 53503],
     [True, 53600],
     [True, 6331],
     [True, 35575],
     [True, 35594],
     [True, 35643]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 8011],
    [False, 20339],
    [False, 20436],
    [False, 38703],
    [False, 2411],
    [False, 2430],
    [False, 2479]]],
  ['control: scenario 4',
   [40000,
    [[False, 63428],
     [False, 10454],
     [True, 36085],
     [False, 36231],
     [True, 36344],
     [True, 36357],
     [True, 36437],
     [True, 36476],
     [True, 59214],
     [False, 59324],
     [True, 23687],
     [True, 45223],
     [False, 61971]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 13],
    [False, 93],
    [False, 132],
    [False, 22870],
    [False, 0],
    [False, 0],
    [False, 21536],
    [False, 0]]]],
 [['regression: scenario 3',
   [1000,
    [[True, 22897],
     [True, 22914],
     [True, 28312],
     [True, 28374],
     [True, 35057],
     [True, 50246],
     [True, 63704],
     [True, 65227],
     [True, 26677],
     [True, 39163]]],
   [[False, 0],
    [False, 17],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000]]],
  ['regression: long enable past a full wrap',
   [1000, [[True, 100], [True, 30100], [True, 60100], [True, 24564], [True, 700]]],
   [[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]],
  ['control: clock wrap',
   [100, [[True, 65500], [True, 65530], [True, 40], [True, 64], [False, 70]]],
   [[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]],
  ['regression: elapsed returns to zero',
   [5, [[True, 10], [True, 20], [True, 10], [True, 12]]],
   [[False, 0], [True, 5], [True, 5], [True, 5]]],
  ['regression: enable after idle',
   [50, [[False, 0], [False, 400], [True, 900], [True, 930], [True, 960]]],
   [[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]],
  ['control: scenario 1',
   [40000,
    [[True, 14860],
     [True, 43167],
     [True, 43310],
     [True, 43470],
     [False, 65246],
     [False, 2333],
     [True, 20092],
     [True, 45967],
     [False, 64834],
     [True, 20225],
     [False, 20250],
     [True, 21773],
     [True, 26780]]],
   [[False, 0],
    [False, 28307],
    [False, 28450],
    [False, 28610],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 25875],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 5007]]],
  ['regression: scenario 2',
   [1000,
    [[True, 51184],
     [True, 56535],
     [True, 13279],
     [True, 24517],
     [True, 24685],
     [True, 32146],
     [True, 59255],
     [False, 21739],
     [True, 21822],
     [True, 43196]]],
   [[False, 0],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [False, 0],
    [False, 0],
    [True, 1000]]],
  ['regression: scenario 4',
   [1000,
    [[True, 38985],
     [True, 39119],
     [True, 46977],
     [True, 47168],
     [False, 6446],
     [True, 33057],
     [True, 33083],
     [True, 33130],
     [True, 49169],
     [True, 49195],
     [True, 49212],
     [True, 12968],
     [True, 13081]]],
   [[False, 0],
    [False, 134],
    [True, 1000],
    [True, 1000],
    [False, 0],
    [False, 0],
    [False, 26],
    [False, 73],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000]]]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression: long enable past a full wrap[[False, 0], [True, 30000], [True, 60000], [True, 24464], [True, 600]][[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]Failed
regression: elapsed returns to zero[[False, 0], [True, 10], [True, 0], [True, 2]][[False, 0], [True, 5], [True, 5], [True, 5]]Failed
control: clock wrap[[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]][[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]Passed
regression: enable after idle[[False, 0], [False, 0], [False, 0], [False, 30], [True, 60]][[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]Failed
regression: scenario 1[[False, 0], [False, 42], [True, 22155], [False, 0], [False, 0], [True, 10811], [True, 10948], [True, 11038], [True, 40726], [True, 40826], [True, 40956]][[False, 0], [False, 42], [True, 100], [False, 0], [False, 0], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100]]Failed
regression: scenario 2[[False, 0], [True, 3227], [True, 10255], [False, 0], [False, 0], [True, 26511], [True, 26546], [True, 26720], [True, 51573]][[False, 0], [True, 100], [True, 100], [False, 0], [False, 0], [True, 100], [True, 100], [True, 100], [True, 100]]Failed
control: scenario 3[[False, 0], [False, 0], [False, 0], [False, 4187], [False, 0], [False, 0], [False, 0], [False, 11775], [False, 11911]][[False, 0], [False, 0], [False, 0], [False, 4187], [False, 0], [False, 0], [False, 0], [False, 11775], [False, 11911]]Passed
regression: scenario 4[[False, 0], [True, 15969], [True, 16002], [True, 16012], [True, 42665], [True, 42675], [True, 53217], [False, 0]][[False, 0], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [False, 0]]Failed

SHA-256 / e21ddd737bd9696c748238e57b3487ca708b0fbfa8deffde2dd8e7d0b1797bee

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(preset, samples):
    start = None
    done = False
    out = []
    for enable, clock in samples:
        if not enable:
            start = None
            done = False
            out.append([False, 0])
            continue
        if start is None:
            start = clock
        elapsed = (clock - start) & 0xFFFF
        if elapsed >= preset:
            done = True
        out.append([done, min(elapsed, preset)])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: long enable past a full wrap',
   [1000, [[True, 100], [True, 30100], [True, 60100], [True, 24564], [True, 700]]],
   [[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]],
  ['regression: elapsed returns to zero',
   [5, [[True, 10], [True, 20], [True, 10], [True, 12]]],
   [[False, 0], [True, 5], [True, 5], [True, 5]]],
  ['control: clock wrap',
   [100, [[True, 65500], [True, 65530], [True, 40], [True, 64], [False, 70]]],
   [[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]],
  ['regression: enable after idle',
   [50, [[False, 0], [False, 400], [True, 900], [True, 930], [True, 960]]],
   [[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]],
  ['regression: scenario 1',
   [100,
    [[True, 53593],
     [True, 53635],
     [True, 10212],
     [False, 10250],
     [True, 24553],
     [True, 35364],
     [True, 35501],
     [True, 35591],
     [True, 65279],
     [True, 65379],
     [True, 65509]]],
   [[False, 0],
    [False, 42],
    [True, 100],
    [False, 0],
    [False, 0],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100]]],
  ['regression: scenario 2',
   [100,
    [[True, 17304],
     [True, 20531],
     [True, 27559],
     [False, 57396],
     [True, 19489],
     [True, 46000],
     [True, 46035],
     [True, 46209],
     [True, 5526]]],
   [[False, 0],
    [True, 100],
    [True, 100],
    [False, 0],
    [False, 0],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100]]],
  ['control: scenario 3',
   [40000,
    [[True, 42783],
     [False, 4625],
     [True, 4670],
     [True, 8857],
     [False, 15422],
     [False, 15500],
     [True, 15560],
     [True, 27335],
     [True, 27471]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 4187],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 11775],
    [False, 11911]]],
  ['regression: scenario 4',
   [100,
    [[True, 2607],
     [True, 18576],
     [True, 18609],
     [True, 18619],
     [True, 45272],
     [True, 45282],
     [True, 55824],
     [False, 61503]]],
   [[False, 0], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [False, 0]]]],
 [['regression: elapsed returns to zero',
   [5, [[True, 10], [True, 20], [True, 10], [True, 12]]],
   [[False, 0], [True, 5], [True, 5], [True, 5]]],
  ['regression: long enable past a full wrap',
   [1000, [[True, 100], [True, 30100], [True, 60100], [True, 24564], [True, 700]]],
   [[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]],
  ['control: clock wrap',
   [100, [[True, 65500], [True, 65530], [True, 40], [True, 64], [False, 70]]],
   [[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]],
  ['regression: enable after idle',
   [50, [[False, 0], [False, 400], [True, 900], [True, 930], [True, 960]]],
   [[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]],
  ['regression: scenario 1',
   [1000,
    [[False, 39404],
     [False, 39599],
     [True, 39752],
     [True, 39914],
     [False, 49270],
     [True, 53547],
     [True, 53700],
     [True, 4426]]],
   [[False, 0], [False, 0], [False, 0], [False, 162], [False, 0], [False, 0], [False, 153], [True, 1000]]],
  ['regression: scenario 2',
   [5,
    [[True, 40525],
     [True, 40666],
     [True, 40725],
     [True, 58227],
     [True, 18319],
     [False, 25775],
     [True, 25797],
     [True, 25799]]],
   [[False, 0], [True, 5], [True, 5], [True, 5], [True, 5], [False, 0], [False, 0], [False, 2]]],
  ['regression: scenario 3',
   [5,
    [[False, 30258],
     [True, 30296],
     [True, 45510],
     [True, 2343],
     [True, 12538],
     [True, 12596],
     [False, 12635],
     [True, 37410],
     [True, 53676],
     [True, 10497],
     [True, 10628],
     [False, 10824],
     [True, 27527],
     [True, 55148]]],
   [[False, 0],
    [False, 0],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [False, 0],
    [False, 0],
    [True, 5],
    [True, 5],
    [True, 5],
    [False, 0],
    [False, 0],
    [True, 5]]],
  ['control: scenario 4',
   [65535,
    [[True, 43066],
     [True, 60153],
     [False, 2292],
     [True, 2392],
     [True, 12076],
     [False, 28626],
     [False, 28693],
     [False, 45850],
     [True, 5636]]],
   [[False, 0],
    [False, 17087],
    [False, 0],
    [False, 0],
    [False, 9684],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0]]]],
 [['regression: enable after idle',
   [50, [[False, 0], [False, 400], [True, 900], [True, 930], [True, 960]]],
   [[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]],
  ['regression: scenario 2',
   [40000,
    [[True, 54821],
     [True, 18035],
     [True, 32212],
     [True, 38340],
     [True, 38521],
     [True, 38565],
     [True, 38691],
     [True, 52834],
     [True, 6573],
     [False, 6717],
     [True, 13602]]],
   [[False, 0],
    [False, 28750],
    [True, 40000],
    [True, 40000],
    [True, 40000],
    [True, 40000],
    [True, 40000],
    [True, 40000],
    [True, 40000],
    [False, 0],
    [False, 0]]],
  ['control: clock wrap',
   [100, [[True, 65500], [True, 65530], [True, 40], [True, 64], [False, 70]]],
   [[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]],
  ['regression: long enable past a full wrap',
   [1000, [[True, 100], [True, 30100], [True, 60100], [True, 24564], [True, 700]]],
   [[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]],
  ['regression: elapsed returns to zero',
   [5, [[True, 10], [True, 20], [True, 10], [True, 12]]],
   [[False, 0], [True, 5], [True, 5], [True, 5]]],
  ['regression: scenario 1',
   [100,
    [[False, 22859],
     [True, 23009],
     [True, 46893],
     [True, 47082],
     [True, 47173],
     [True, 47274],
     [False, 47358],
     [True, 47448],
     [True, 54303],
     [True, 54477],
     [False, 54574]]],
   [[False, 0],
    [False, 0],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [False, 0],
    [False, 0],
    [True, 100],
    [True, 100],
    [False, 0]]],
  ['regression: scenario 3',
   [5,
    [[False, 23870],
     [True, 46782],
     [True, 46917],
     [True, 46976],
     [True, 56255],
     [True, 61627],
     [True, 1767],
     [True, 1874]]],
   [[False, 0], [False, 0], [True, 5], [True, 5], [True, 5], [True, 5], [True, 5], [True, 5]]],
  ['regression: scenario 4',
   [5,
    [[True, 25219],
     [True, 25303],
     [True, 25491],
     [True, 33180],
     [True, 33370],
     [True, 34085],
     [True, 35832],
     [True, 46392],
     [True, 48652],
     [True, 48709],
     [True, 6073],
     [True, 6100]]],
   [[False, 0],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5]]]],
 [['regression: scenario 2',
   [1000,
    [[False, 46148],
     [True, 57365],
     [False, 57416],
     [True, 57439],
     [True, 57613],
     [True, 57776],
     [True, 61872],
     [True, 62038],
     [True, 9532],
     [True, 32841],
     [True, 32973]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 174],
    [False, 337],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000]]],
  ['regression: long enable past a full wrap',
   [1000, [[True, 100], [True, 30100], [True, 60100], [True, 24564], [True, 700]]],
   [[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]],
  ['control: clock wrap',
   [100, [[True, 65500], [True, 65530], [True, 40], [True, 64], [False, 70]]],
   [[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]],
  ['regression: elapsed returns to zero',
   [5, [[True, 10], [True, 20], [True, 10], [True, 12]]],
   [[False, 0], [True, 5], [True, 5], [True, 5]]],
  ['regression: enable after idle',
   [50, [[False, 0], [False, 400], [True, 900], [True, 930], [True, 960]]],
   [[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]],
  ['control: scenario 1',
   [65535,
    [[False, 3784],
     [False, 8211],
     [False, 33966],
     [True, 50163],
     [True, 63009],
     [False, 63184],
     [True, 63243],
     [True, 63325]]],
   [[False, 0], [False, 0], [False, 0], [False, 0], [False, 12846], [False, 0], [False, 0], [False, 82]]],
  ['control: scenario 3',
   [65535,
    [[False, 15447],
     [True, 18837],
     [False, 18898],
     [True, 19006],
     [False, 33164],
     [True, 33164],
     [True, 41175],
     [True, 53503],
     [True, 53600],
     [True, 6331],
     [True, 35575],
     [True, 35594],
     [True, 35643]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 8011],
    [False, 20339],
    [False, 20436],
    [False, 38703],
    [False, 2411],
    [False, 2430],
    [False, 2479]]],
  ['control: scenario 4',
   [40000,
    [[False, 63428],
     [False, 10454],
     [True, 36085],
     [False, 36231],
     [True, 36344],
     [True, 36357],
     [True, 36437],
     [True, 36476],
     [True, 59214],
     [False, 59324],
     [True, 23687],
     [True, 45223],
     [False, 61971]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 13],
    [False, 93],
    [False, 132],
    [False, 22870],
    [False, 0],
    [False, 0],
    [False, 21536],
    [False, 0]]]],
 [['regression: scenario 3',
   [1000,
    [[True, 22897],
     [True, 22914],
     [True, 28312],
     [True, 28374],
     [True, 35057],
     [True, 50246],
     [True, 63704],
     [True, 65227],
     [True, 26677],
     [True, 39163]]],
   [[False, 0],
    [False, 17],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000]]],
  ['regression: long enable past a full wrap',
   [1000, [[True, 100], [True, 30100], [True, 60100], [True, 24564], [True, 700]]],
   [[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]],
  ['control: clock wrap',
   [100, [[True, 65500], [True, 65530], [True, 40], [True, 64], [False, 70]]],
   [[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]],
  ['regression: elapsed returns to zero',
   [5, [[True, 10], [True, 20], [True, 10], [True, 12]]],
   [[False, 0], [True, 5], [True, 5], [True, 5]]],
  ['regression: enable after idle',
   [50, [[False, 0], [False, 400], [True, 900], [True, 930], [True, 960]]],
   [[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]],
  ['control: scenario 1',
   [40000,
    [[True, 14860],
     [True, 43167],
     [True, 43310],
     [True, 43470],
     [False, 65246],
     [False, 2333],
     [True, 20092],
     [True, 45967],
     [False, 64834],
     [True, 20225],
     [False, 20250],
     [True, 21773],
     [True, 26780]]],
   [[False, 0],
    [False, 28307],
    [False, 28450],
    [False, 28610],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 25875],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 5007]]],
  ['regression: scenario 2',
   [1000,
    [[True, 51184],
     [True, 56535],
     [True, 13279],
     [True, 24517],
     [True, 24685],
     [True, 32146],
     [True, 59255],
     [False, 21739],
     [True, 21822],
     [True, 43196]]],
   [[False, 0],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [False, 0],
    [False, 0],
    [True, 1000]]],
  ['regression: scenario 4',
   [1000,
    [[True, 38985],
     [True, 39119],
     [True, 46977],
     [True, 47168],
     [False, 6446],
     [True, 33057],
     [True, 33083],
     [True, 33130],
     [True, 49169],
     [True, 49195],
     [True, 49212],
     [True, 12968],
     [True, 13081]]],
   [[False, 0],
    [False, 134],
    [True, 1000],
    [True, 1000],
    [False, 0],
    [False, 0],
    [False, 26],
    [False, 73],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000]]]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression: long enable past a full wrap[[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 600]][[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]Failed
regression: elapsed returns to zero[[False, 0], [True, 5], [True, 0], [True, 2]][[False, 0], [True, 5], [True, 5], [True, 5]]Failed
control: clock wrap[[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]][[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]Passed
regression: enable after idle[[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]][[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]Passed
regression: scenario 1[[False, 0], [False, 42], [True, 100], [False, 0], [False, 0], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100]][[False, 0], [False, 42], [True, 100], [False, 0], [False, 0], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100]]Passed
regression: scenario 2[[False, 0], [True, 100], [True, 100], [False, 0], [False, 0], [True, 100], [True, 100], [True, 100], [True, 100]][[False, 0], [True, 100], [True, 100], [False, 0], [False, 0], [True, 100], [True, 100], [True, 100], [True, 100]]Passed
control: scenario 3[[False, 0], [False, 0], [False, 0], [False, 4187], [False, 0], [False, 0], [False, 0], [False, 11775], [False, 11911]][[False, 0], [False, 0], [False, 0], [False, 4187], [False, 0], [False, 0], [False, 0], [False, 11775], [False, 11911]]Passed
regression: scenario 4[[False, 0], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [False, 0]][[False, 0], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [False, 0]]Passed

SHA-256 / d965d42816b354248f69171e3e8c5e4d88aa6122d51d347b259ff167d81ea697

3 / The verified repair

Exit 0
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(preset, samples):
    start = None
    done = False
    out = []
    for enable, clock in samples:
        if not enable:
            start = None
            done = False
            out.append([False, 0])
            continue
        if start is None:
            start = clock
        elapsed = (clock - start) & 0xFFFF
        if elapsed >= preset:
            done = True
        out.append([done, preset if done else elapsed])
    return out
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: long enable past a full wrap',
   [1000, [[True, 100], [True, 30100], [True, 60100], [True, 24564], [True, 700]]],
   [[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]],
  ['regression: elapsed returns to zero',
   [5, [[True, 10], [True, 20], [True, 10], [True, 12]]],
   [[False, 0], [True, 5], [True, 5], [True, 5]]],
  ['control: clock wrap',
   [100, [[True, 65500], [True, 65530], [True, 40], [True, 64], [False, 70]]],
   [[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]],
  ['regression: enable after idle',
   [50, [[False, 0], [False, 400], [True, 900], [True, 930], [True, 960]]],
   [[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]],
  ['regression: scenario 1',
   [100,
    [[True, 53593],
     [True, 53635],
     [True, 10212],
     [False, 10250],
     [True, 24553],
     [True, 35364],
     [True, 35501],
     [True, 35591],
     [True, 65279],
     [True, 65379],
     [True, 65509]]],
   [[False, 0],
    [False, 42],
    [True, 100],
    [False, 0],
    [False, 0],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100]]],
  ['regression: scenario 2',
   [100,
    [[True, 17304],
     [True, 20531],
     [True, 27559],
     [False, 57396],
     [True, 19489],
     [True, 46000],
     [True, 46035],
     [True, 46209],
     [True, 5526]]],
   [[False, 0],
    [True, 100],
    [True, 100],
    [False, 0],
    [False, 0],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100]]],
  ['control: scenario 3',
   [40000,
    [[True, 42783],
     [False, 4625],
     [True, 4670],
     [True, 8857],
     [False, 15422],
     [False, 15500],
     [True, 15560],
     [True, 27335],
     [True, 27471]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 4187],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 11775],
    [False, 11911]]],
  ['regression: scenario 4',
   [100,
    [[True, 2607],
     [True, 18576],
     [True, 18609],
     [True, 18619],
     [True, 45272],
     [True, 45282],
     [True, 55824],
     [False, 61503]]],
   [[False, 0], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [False, 0]]]],
 [['regression: elapsed returns to zero',
   [5, [[True, 10], [True, 20], [True, 10], [True, 12]]],
   [[False, 0], [True, 5], [True, 5], [True, 5]]],
  ['regression: long enable past a full wrap',
   [1000, [[True, 100], [True, 30100], [True, 60100], [True, 24564], [True, 700]]],
   [[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]],
  ['control: clock wrap',
   [100, [[True, 65500], [True, 65530], [True, 40], [True, 64], [False, 70]]],
   [[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]],
  ['regression: enable after idle',
   [50, [[False, 0], [False, 400], [True, 900], [True, 930], [True, 960]]],
   [[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]],
  ['regression: scenario 1',
   [1000,
    [[False, 39404],
     [False, 39599],
     [True, 39752],
     [True, 39914],
     [False, 49270],
     [True, 53547],
     [True, 53700],
     [True, 4426]]],
   [[False, 0], [False, 0], [False, 0], [False, 162], [False, 0], [False, 0], [False, 153], [True, 1000]]],
  ['regression: scenario 2',
   [5,
    [[True, 40525],
     [True, 40666],
     [True, 40725],
     [True, 58227],
     [True, 18319],
     [False, 25775],
     [True, 25797],
     [True, 25799]]],
   [[False, 0], [True, 5], [True, 5], [True, 5], [True, 5], [False, 0], [False, 0], [False, 2]]],
  ['regression: scenario 3',
   [5,
    [[False, 30258],
     [True, 30296],
     [True, 45510],
     [True, 2343],
     [True, 12538],
     [True, 12596],
     [False, 12635],
     [True, 37410],
     [True, 53676],
     [True, 10497],
     [True, 10628],
     [False, 10824],
     [True, 27527],
     [True, 55148]]],
   [[False, 0],
    [False, 0],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [False, 0],
    [False, 0],
    [True, 5],
    [True, 5],
    [True, 5],
    [False, 0],
    [False, 0],
    [True, 5]]],
  ['control: scenario 4',
   [65535,
    [[True, 43066],
     [True, 60153],
     [False, 2292],
     [True, 2392],
     [True, 12076],
     [False, 28626],
     [False, 28693],
     [False, 45850],
     [True, 5636]]],
   [[False, 0],
    [False, 17087],
    [False, 0],
    [False, 0],
    [False, 9684],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0]]]],
 [['regression: enable after idle',
   [50, [[False, 0], [False, 400], [True, 900], [True, 930], [True, 960]]],
   [[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]],
  ['regression: scenario 2',
   [40000,
    [[True, 54821],
     [True, 18035],
     [True, 32212],
     [True, 38340],
     [True, 38521],
     [True, 38565],
     [True, 38691],
     [True, 52834],
     [True, 6573],
     [False, 6717],
     [True, 13602]]],
   [[False, 0],
    [False, 28750],
    [True, 40000],
    [True, 40000],
    [True, 40000],
    [True, 40000],
    [True, 40000],
    [True, 40000],
    [True, 40000],
    [False, 0],
    [False, 0]]],
  ['control: clock wrap',
   [100, [[True, 65500], [True, 65530], [True, 40], [True, 64], [False, 70]]],
   [[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]],
  ['regression: long enable past a full wrap',
   [1000, [[True, 100], [True, 30100], [True, 60100], [True, 24564], [True, 700]]],
   [[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]],
  ['regression: elapsed returns to zero',
   [5, [[True, 10], [True, 20], [True, 10], [True, 12]]],
   [[False, 0], [True, 5], [True, 5], [True, 5]]],
  ['regression: scenario 1',
   [100,
    [[False, 22859],
     [True, 23009],
     [True, 46893],
     [True, 47082],
     [True, 47173],
     [True, 47274],
     [False, 47358],
     [True, 47448],
     [True, 54303],
     [True, 54477],
     [False, 54574]]],
   [[False, 0],
    [False, 0],
    [True, 100],
    [True, 100],
    [True, 100],
    [True, 100],
    [False, 0],
    [False, 0],
    [True, 100],
    [True, 100],
    [False, 0]]],
  ['regression: scenario 3',
   [5,
    [[False, 23870],
     [True, 46782],
     [True, 46917],
     [True, 46976],
     [True, 56255],
     [True, 61627],
     [True, 1767],
     [True, 1874]]],
   [[False, 0], [False, 0], [True, 5], [True, 5], [True, 5], [True, 5], [True, 5], [True, 5]]],
  ['regression: scenario 4',
   [5,
    [[True, 25219],
     [True, 25303],
     [True, 25491],
     [True, 33180],
     [True, 33370],
     [True, 34085],
     [True, 35832],
     [True, 46392],
     [True, 48652],
     [True, 48709],
     [True, 6073],
     [True, 6100]]],
   [[False, 0],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5],
    [True, 5]]]],
 [['regression: scenario 2',
   [1000,
    [[False, 46148],
     [True, 57365],
     [False, 57416],
     [True, 57439],
     [True, 57613],
     [True, 57776],
     [True, 61872],
     [True, 62038],
     [True, 9532],
     [True, 32841],
     [True, 32973]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 174],
    [False, 337],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000]]],
  ['regression: long enable past a full wrap',
   [1000, [[True, 100], [True, 30100], [True, 60100], [True, 24564], [True, 700]]],
   [[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]],
  ['control: clock wrap',
   [100, [[True, 65500], [True, 65530], [True, 40], [True, 64], [False, 70]]],
   [[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]],
  ['regression: elapsed returns to zero',
   [5, [[True, 10], [True, 20], [True, 10], [True, 12]]],
   [[False, 0], [True, 5], [True, 5], [True, 5]]],
  ['regression: enable after idle',
   [50, [[False, 0], [False, 400], [True, 900], [True, 930], [True, 960]]],
   [[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]],
  ['control: scenario 1',
   [65535,
    [[False, 3784],
     [False, 8211],
     [False, 33966],
     [True, 50163],
     [True, 63009],
     [False, 63184],
     [True, 63243],
     [True, 63325]]],
   [[False, 0], [False, 0], [False, 0], [False, 0], [False, 12846], [False, 0], [False, 0], [False, 82]]],
  ['control: scenario 3',
   [65535,
    [[False, 15447],
     [True, 18837],
     [False, 18898],
     [True, 19006],
     [False, 33164],
     [True, 33164],
     [True, 41175],
     [True, 53503],
     [True, 53600],
     [True, 6331],
     [True, 35575],
     [True, 35594],
     [True, 35643]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 8011],
    [False, 20339],
    [False, 20436],
    [False, 38703],
    [False, 2411],
    [False, 2430],
    [False, 2479]]],
  ['control: scenario 4',
   [40000,
    [[False, 63428],
     [False, 10454],
     [True, 36085],
     [False, 36231],
     [True, 36344],
     [True, 36357],
     [True, 36437],
     [True, 36476],
     [True, 59214],
     [False, 59324],
     [True, 23687],
     [True, 45223],
     [False, 61971]]],
   [[False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 13],
    [False, 93],
    [False, 132],
    [False, 22870],
    [False, 0],
    [False, 0],
    [False, 21536],
    [False, 0]]]],
 [['regression: scenario 3',
   [1000,
    [[True, 22897],
     [True, 22914],
     [True, 28312],
     [True, 28374],
     [True, 35057],
     [True, 50246],
     [True, 63704],
     [True, 65227],
     [True, 26677],
     [True, 39163]]],
   [[False, 0],
    [False, 17],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000]]],
  ['regression: long enable past a full wrap',
   [1000, [[True, 100], [True, 30100], [True, 60100], [True, 24564], [True, 700]]],
   [[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]],
  ['control: clock wrap',
   [100, [[True, 65500], [True, 65530], [True, 40], [True, 64], [False, 70]]],
   [[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]],
  ['regression: elapsed returns to zero',
   [5, [[True, 10], [True, 20], [True, 10], [True, 12]]],
   [[False, 0], [True, 5], [True, 5], [True, 5]]],
  ['regression: enable after idle',
   [50, [[False, 0], [False, 400], [True, 900], [True, 930], [True, 960]]],
   [[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]],
  ['control: scenario 1',
   [40000,
    [[True, 14860],
     [True, 43167],
     [True, 43310],
     [True, 43470],
     [False, 65246],
     [False, 2333],
     [True, 20092],
     [True, 45967],
     [False, 64834],
     [True, 20225],
     [False, 20250],
     [True, 21773],
     [True, 26780]]],
   [[False, 0],
    [False, 28307],
    [False, 28450],
    [False, 28610],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 25875],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 0],
    [False, 5007]]],
  ['regression: scenario 2',
   [1000,
    [[True, 51184],
     [True, 56535],
     [True, 13279],
     [True, 24517],
     [True, 24685],
     [True, 32146],
     [True, 59255],
     [False, 21739],
     [True, 21822],
     [True, 43196]]],
   [[False, 0],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [False, 0],
    [False, 0],
    [True, 1000]]],
  ['regression: scenario 4',
   [1000,
    [[True, 38985],
     [True, 39119],
     [True, 46977],
     [True, 47168],
     [False, 6446],
     [True, 33057],
     [True, 33083],
     [True, 33130],
     [True, 49169],
     [True, 49195],
     [True, 49212],
     [True, 12968],
     [True, 13081]]],
   [[False, 0],
    [False, 134],
    [True, 1000],
    [True, 1000],
    [False, 0],
    [False, 0],
    [False, 26],
    [False, 73],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000],
    [True, 1000]]]]]
for label, args, expected in fixtures[N-1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
regression: long enable past a full wrap[[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]][[False, 0], [True, 1000], [True, 1000], [True, 1000], [True, 1000]]Passed
regression: elapsed returns to zero[[False, 0], [True, 5], [True, 5], [True, 5]][[False, 0], [True, 5], [True, 5], [True, 5]]Passed
control: clock wrap[[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]][[False, 0], [False, 30], [False, 76], [True, 100], [False, 0]]Passed
regression: enable after idle[[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]][[False, 0], [False, 0], [False, 0], [False, 30], [True, 50]]Passed
regression: scenario 1[[False, 0], [False, 42], [True, 100], [False, 0], [False, 0], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100]][[False, 0], [False, 42], [True, 100], [False, 0], [False, 0], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100]]Passed
regression: scenario 2[[False, 0], [True, 100], [True, 100], [False, 0], [False, 0], [True, 100], [True, 100], [True, 100], [True, 100]][[False, 0], [True, 100], [True, 100], [False, 0], [False, 0], [True, 100], [True, 100], [True, 100], [True, 100]]Passed
control: scenario 3[[False, 0], [False, 0], [False, 0], [False, 4187], [False, 0], [False, 0], [False, 0], [False, 11775], [False, 11911]][[False, 0], [False, 0], [False, 0], [False, 4187], [False, 0], [False, 0], [False, 0], [False, 11775], [False, 11911]]Passed
regression: scenario 4[[False, 0], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [False, 0]][[False, 0], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [True, 100], [False, 0]]Passed

SHA-256 / 9ce84f5c097a901916fd478f8deb7f75ac24f6011d02e8bb68edc401deb9d7e0

Verification & scope

A deterministic bounded teaching model of one PLC instruction or rung pattern evaluated scan by scan. The stated contract is a stipulated toy convention, not a claim of conformance to any vendor controller or IEC 61131-3 runtime. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:51:44.027287+00:00.

Case digest / 8bb2e99f3b04593a7cded4f59b085a5128df8d118813faa1145b0fdcfab5b3bb