FA-91846 / PLC ladder logic scan cycles / Open access
TON accumulator runs past its preset · case 01
After the delay completes the ACC value keeps growing on every true scan instead of holding at PRE.
ROOT CAUSE
The accumulator addition is not limited to the preset.
VERIFIED REPAIR
Clamp the accumulator at preset after adding the scan interval.
Unsuccessful approach: Clamping before the addition still leaves ACC one scan interval above PRE.
Case contract
On-delay timer (TON) evaluated once per scan. scans is a list of [rung_in, elapsed_ms since the previous scan]. The accumulator starts on the false-to-true scan without crediting that scan's elapsed time, then adds each later true scan's elapsed time, clamped at preset. A false rung resets the accumulator. DN is rung_in and acc >= preset; TT is rung_in and not DN. Return [DN, TT, ACC] per scan.
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, scans):
acc = 0
prev = False
out = []
for rung_in, dt in scans:
rung_in = bool(rung_in)
if rung_in and prev:
acc = acc + dt
elif not rung_in:
acc = 0
dn = rung_in and acc >= preset
tt = rung_in and not dn
prev = rung_in
out.append([dn, tt, acc])
return out
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: preset reached exactly',
[100, [[True, 30], [True, 50], [True, 50], [True, 10]]],
[[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]]],
['regression: interrupted timing restarts',
[60, [[True, 40], [True, 40], [False, 40], [True, 40], [True, 40], [True, 40]]],
[[False, True, 0],
[False, True, 40],
[False, False, 0],
[False, True, 0],
[False, True, 40],
[True, False, 60]]],
['control: zero preset',
[0, [[False, 10], [True, 10], [False, 5], [True, 40]]],
[[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]]],
['regression: long hold after done',
[50, [[True, 30], [True, 30], [True, 30], [True, 30], [False, 30]]],
[[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]]],
['regression: scenario 1',
[30, [[True, 40], [False, 75], [True, 60], [False, 25], [False, 10], [True, 60], [True, 25], [True, 40]]],
[[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 25],
[True, False, 30]]],
['regression: scenario 2',
[30, [[False, 25], [True, 50], [True, 0], [True, 0], [True, 25], [True, 75], [True, 75]]],
[[False, False, 0],
[False, True, 0],
[False, True, 0],
[False, True, 0],
[False, True, 25],
[True, False, 30],
[True, False, 30]]],
['control: scenario 3',
[120, [[True, 25], [True, 20], [False, 75], [True, 75], [True, 0], [False, 10], [True, 25]]],
[[False, True, 0],
[False, True, 20],
[False, False, 0],
[False, True, 0],
[False, True, 0],
[False, False, 0],
[False, True, 0]]],
['regression: scenario 4',
[0,
[[True, 10],
[False, 25],
[True, 25],
[True, 20],
[True, 40],
[True, 20],
[True, 75],
[True, 0],
[True, 10]]],
[[True, False, 0],
[False, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0]]]],
[['regression: interrupted timing restarts',
[60, [[True, 40], [True, 40], [False, 40], [True, 40], [True, 40], [True, 40]]],
[[False, True, 0],
[False, True, 40],
[False, False, 0],
[False, True, 0],
[False, True, 40],
[True, False, 60]]],
['regression: long hold after done',
[50, [[True, 30], [True, 30], [True, 30], [True, 30], [False, 30]]],
[[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]]],
['regression: preset reached exactly',
[100, [[True, 30], [True, 50], [True, 50], [True, 10]]],
[[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]]],
['control: zero preset',
[0, [[False, 10], [True, 10], [False, 5], [True, 40]]],
[[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]]],
['regression: scenario 1',
[0,
[[True, 40],
[True, 10],
[True, 10],
[False, 10],
[True, 20],
[True, 25],
[True, 20],
[False, 25],
[True, 20]]],
[[True, False, 0],
[True, False, 0],
[True, False, 0],
[False, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0],
[False, False, 0],
[True, False, 0]]],
['control: scenario 2',
[150,
[[True, 60],
[True, 10],
[False, 20],
[False, 40],
[True, 50],
[True, 25],
[False, 25],
[False, 75],
[True, 25],
[False, 0],
[True, 60],
[False, 10]]],
[[False, True, 0],
[False, True, 10],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 25],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0]]],
['regression: scenario 3',
[50,
[[False, 50],
[True, 75],
[True, 75],
[True, 20],
[True, 75],
[True, 0],
[False, 60],
[True, 25],
[False, 10]]],
[[False, False, 0],
[False, True, 0],
[True, False, 50],
[True, False, 50],
[True, False, 50],
[True, False, 50],
[False, False, 0],
[False, True, 0],
[False, False, 0]]],
['regression: scenario 4',
[120,
[[True, 75],
[False, 60],
[True, 20],
[True, 25],
[False, 40],
[False, 40],
[True, 50],
[True, 60],
[True, 75],
[True, 40],
[True, 0]]],
[[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, True, 25],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 60],
[True, False, 120],
[True, False, 120],
[True, False, 120]]]],
[['regression: long hold after done',
[50, [[True, 30], [True, 30], [True, 30], [True, 30], [False, 30]]],
[[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]]],
['regression: scenario 1',
[50,
[[True, 75],
[True, 40],
[True, 60],
[True, 0],
[True, 25],
[False, 50],
[False, 75],
[True, 60],
[True, 20],
[True, 60],
[False, 60],
[True, 75]]],
[[False, True, 0],
[False, True, 40],
[True, False, 50],
[True, False, 50],
[True, False, 50],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 20],
[True, False, 50],
[False, False, 0],
[False, True, 0]]],
['regression: preset reached exactly',
[100, [[True, 30], [True, 50], [True, 50], [True, 10]]],
[[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]]],
['control: zero preset',
[0, [[False, 10], [True, 10], [False, 5], [True, 40]]],
[[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]]],
['regression: interrupted timing restarts',
[60, [[True, 40], [True, 40], [False, 40], [True, 40], [True, 40], [True, 40]]],
[[False, True, 0],
[False, True, 40],
[False, False, 0],
[False, True, 0],
[False, True, 40],
[True, False, 60]]],
['control: scenario 2',
[120, [[False, 0], [False, 75], [True, 75], [True, 0], [True, 0], [False, 75], [True, 60], [True, 40]]],
[[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 0],
[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, True, 40]]],
['control: scenario 3',
[50,
[[True, 40],
[False, 0],
[True, 60],
[True, 0],
[True, 40],
[True, 0],
[True, 0],
[False, 0],
[False, 50],
[False, 60],
[False, 10],
[True, 60]]],
[[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, True, 0],
[False, True, 40],
[False, True, 40],
[False, True, 40],
[False, False, 0],
[False, False, 0],
[False, False, 0],
[False, False, 0],
[False, True, 0]]],
['control: scenario 4',
[100, [[False, 60], [False, 20], [True, 75], [False, 25], [True, 60], [False, 25], [True, 40]]],
[[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0],
[False, True, 0]]]],
[['regression: scenario 1',
[0,
[[True, 10],
[True, 0],
[False, 50],
[True, 40],
[False, 20],
[False, 25],
[True, 50],
[True, 60],
[True, 40]]],
[[True, False, 0],
[True, False, 0],
[False, False, 0],
[True, False, 0],
[False, False, 0],
[False, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0]]],
['regression: scenario 3',
[120,
[[True, 60],
[True, 10],
[False, 10],
[True, 50],
[True, 20],
[True, 25],
[True, 25],
[False, 75],
[True, 40],
[True, 50],
[True, 75],
[True, 0]]],
[[False, True, 0],
[False, True, 10],
[False, False, 0],
[False, True, 0],
[False, True, 20],
[False, True, 45],
[False, True, 70],
[False, False, 0],
[False, True, 0],
[False, True, 50],
[True, False, 120],
[True, False, 120]]],
['regression: preset reached exactly',
[100, [[True, 30], [True, 50], [True, 50], [True, 10]]],
[[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]]],
['control: zero preset',
[0, [[False, 10], [True, 10], [False, 5], [True, 40]]],
[[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]]],
['regression: interrupted timing restarts',
[60, [[True, 40], [True, 40], [False, 40], [True, 40], [True, 40], [True, 40]]],
[[False, True, 0],
[False, True, 40],
[False, False, 0],
[False, True, 0],
[False, True, 40],
[True, False, 60]]],
['regression: long hold after done',
[50, [[True, 30], [True, 30], [True, 30], [True, 30], [False, 30]]],
[[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]]],
['control: scenario 2',
[100, [[False, 50], [True, 50], [True, 20], [False, 50], [True, 40], [True, 10], [False, 10]]],
[[False, False, 0],
[False, True, 0],
[False, True, 20],
[False, False, 0],
[False, True, 0],
[False, True, 10],
[False, False, 0]]],
['control: scenario 4',
[0, [[True, 25], [False, 75], [True, 20], [False, 25], [True, 20], [False, 25], [True, 40]]],
[[True, False, 0],
[False, False, 0],
[True, False, 0],
[False, False, 0],
[True, False, 0],
[False, False, 0],
[True, False, 0]]]],
[['regression: scenario 4',
[100,
[[False, 60],
[False, 0],
[True, 50],
[True, 20],
[True, 60],
[True, 20],
[True, 50],
[True, 0],
[True, 20],
[True, 0],
[True, 20],
[True, 25]]],
[[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 20],
[False, True, 80],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100]]],
['regression: scenario 5',
[100,
[[True, 20],
[True, 40],
[True, 20],
[True, 75],
[True, 50],
[True, 75],
[True, 0],
[True, 25],
[False, 50],
[False, 0],
[False, 40]]],
[[False, True, 0],
[False, True, 40],
[False, True, 60],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[False, False, 0],
[False, False, 0],
[False, False, 0]]],
['regression: preset reached exactly',
[100, [[True, 30], [True, 50], [True, 50], [True, 10]]],
[[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]]],
['control: zero preset',
[0, [[False, 10], [True, 10], [False, 5], [True, 40]]],
[[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]]],
['regression: interrupted timing restarts',
[60, [[True, 40], [True, 40], [False, 40], [True, 40], [True, 40], [True, 40]]],
[[False, True, 0],
[False, True, 40],
[False, False, 0],
[False, True, 0],
[False, True, 40],
[True, False, 60]]],
['regression: long hold after done',
[50, [[True, 30], [True, 30], [True, 30], [True, 30], [False, 30]]],
[[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]]],
['regression: scenario 1',
[120,
[[True, 0],
[True, 50],
[True, 50],
[True, 75],
[True, 75],
[False, 40],
[True, 25],
[False, 0],
[False, 10],
[True, 25],
[False, 0]]],
[[False, True, 0],
[False, True, 50],
[False, True, 100],
[True, False, 120],
[True, False, 120],
[False, False, 0],
[False, True, 0],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0]]],
['control: scenario 2',
[150, [[True, 50], [False, 40], [True, 20], [True, 20], [True, 10], [True, 40], [False, 50]]],
[[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, True, 20],
[False, True, 30],
[False, True, 70],
[False, False, 0]]]]]
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 fixture | Actual | Expected | Outcome |
|---|---|---|---|
| regression: preset reached exactly | [[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 110]] | [[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]] | Failed |
| regression: interrupted timing restarts | [[False, True, 0], [False, True, 40], [False, False, 0], [False, True, 0], [False, True, 40], [True, False, 80]] | [[False, True, 0], [False, True, 40], [False, False, 0], [False, True, 0], [False, True, 40], [True, False, 60]] | Failed |
| control: zero preset | [[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]] | [[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]] | Passed |
| regression: long hold after done | [[False, True, 0], [False, True, 30], [True, False, 60], [True, False, 90], [False, False, 0]] | [[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]] | Failed |
| regression: scenario 1 | [[False, True, 0], [False, False, 0], [False, True, 0], [False, False, 0], [False, False, 0], [False, True, 0], [False, True, 25], [True, False, 65]] | [[False, True, 0], [False, False, 0], [False, True, 0], [False, False, 0], [False, False, 0], [False, True, 0], [False, True, 25], [True, False, 30]] | Failed |
| regression: scenario 2 | [[False, False, 0], [False, True, 0], [False, True, 0], [False, True, 0], [False, True, 25], [True, False, 100], [True, False, 175]] | [[False, False, 0], [False, True, 0], [False, True, 0], [False, True, 0], [False, True, 25], [True, False, 30], [True, False, 30]] | Failed |
| control: scenario 3 | [[False, True, 0], [False, True, 20], [False, False, 0], [False, True, 0], [False, True, 0], [False, False, 0], [False, True, 0]] | [[False, True, 0], [False, True, 20], [False, False, 0], [False, True, 0], [False, True, 0], [False, False, 0], [False, True, 0]] | Passed |
| regression: scenario 4 | [[True, False, 0], [False, False, 0], [True, False, 0], [True, False, 20], [True, False, 60], [True, False, 80], [True, False, 155], [True, False, 155], [True, False, 165]] | [[True, False, 0], [False, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0]] | Failed |
SHA-256 / 8481474a498c4f2693f06a681bd68f680f6317659dd6d156a34e9227991a6141
2 / The unsuccessful fix
Exit 1"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(preset, scans):
acc = 0
prev = False
out = []
for rung_in, dt in scans:
rung_in = bool(rung_in)
if rung_in and prev:
acc = min(preset, acc) + dt
elif not rung_in:
acc = 0
dn = rung_in and acc >= preset
tt = rung_in and not dn
prev = rung_in
out.append([dn, tt, acc])
return out
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: preset reached exactly',
[100, [[True, 30], [True, 50], [True, 50], [True, 10]]],
[[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]]],
['regression: interrupted timing restarts',
[60, [[True, 40], [True, 40], [False, 40], [True, 40], [True, 40], [True, 40]]],
[[False, True, 0],
[False, True, 40],
[False, False, 0],
[False, True, 0],
[False, True, 40],
[True, False, 60]]],
['control: zero preset',
[0, [[False, 10], [True, 10], [False, 5], [True, 40]]],
[[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]]],
['regression: long hold after done',
[50, [[True, 30], [True, 30], [True, 30], [True, 30], [False, 30]]],
[[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]]],
['regression: scenario 1',
[30, [[True, 40], [False, 75], [True, 60], [False, 25], [False, 10], [True, 60], [True, 25], [True, 40]]],
[[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 25],
[True, False, 30]]],
['regression: scenario 2',
[30, [[False, 25], [True, 50], [True, 0], [True, 0], [True, 25], [True, 75], [True, 75]]],
[[False, False, 0],
[False, True, 0],
[False, True, 0],
[False, True, 0],
[False, True, 25],
[True, False, 30],
[True, False, 30]]],
['control: scenario 3',
[120, [[True, 25], [True, 20], [False, 75], [True, 75], [True, 0], [False, 10], [True, 25]]],
[[False, True, 0],
[False, True, 20],
[False, False, 0],
[False, True, 0],
[False, True, 0],
[False, False, 0],
[False, True, 0]]],
['regression: scenario 4',
[0,
[[True, 10],
[False, 25],
[True, 25],
[True, 20],
[True, 40],
[True, 20],
[True, 75],
[True, 0],
[True, 10]]],
[[True, False, 0],
[False, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0]]]],
[['regression: interrupted timing restarts',
[60, [[True, 40], [True, 40], [False, 40], [True, 40], [True, 40], [True, 40]]],
[[False, True, 0],
[False, True, 40],
[False, False, 0],
[False, True, 0],
[False, True, 40],
[True, False, 60]]],
['regression: long hold after done',
[50, [[True, 30], [True, 30], [True, 30], [True, 30], [False, 30]]],
[[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]]],
['regression: preset reached exactly',
[100, [[True, 30], [True, 50], [True, 50], [True, 10]]],
[[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]]],
['control: zero preset',
[0, [[False, 10], [True, 10], [False, 5], [True, 40]]],
[[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]]],
['regression: scenario 1',
[0,
[[True, 40],
[True, 10],
[True, 10],
[False, 10],
[True, 20],
[True, 25],
[True, 20],
[False, 25],
[True, 20]]],
[[True, False, 0],
[True, False, 0],
[True, False, 0],
[False, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0],
[False, False, 0],
[True, False, 0]]],
['control: scenario 2',
[150,
[[True, 60],
[True, 10],
[False, 20],
[False, 40],
[True, 50],
[True, 25],
[False, 25],
[False, 75],
[True, 25],
[False, 0],
[True, 60],
[False, 10]]],
[[False, True, 0],
[False, True, 10],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 25],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0]]],
['regression: scenario 3',
[50,
[[False, 50],
[True, 75],
[True, 75],
[True, 20],
[True, 75],
[True, 0],
[False, 60],
[True, 25],
[False, 10]]],
[[False, False, 0],
[False, True, 0],
[True, False, 50],
[True, False, 50],
[True, False, 50],
[True, False, 50],
[False, False, 0],
[False, True, 0],
[False, False, 0]]],
['regression: scenario 4',
[120,
[[True, 75],
[False, 60],
[True, 20],
[True, 25],
[False, 40],
[False, 40],
[True, 50],
[True, 60],
[True, 75],
[True, 40],
[True, 0]]],
[[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, True, 25],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 60],
[True, False, 120],
[True, False, 120],
[True, False, 120]]]],
[['regression: long hold after done',
[50, [[True, 30], [True, 30], [True, 30], [True, 30], [False, 30]]],
[[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]]],
['regression: scenario 1',
[50,
[[True, 75],
[True, 40],
[True, 60],
[True, 0],
[True, 25],
[False, 50],
[False, 75],
[True, 60],
[True, 20],
[True, 60],
[False, 60],
[True, 75]]],
[[False, True, 0],
[False, True, 40],
[True, False, 50],
[True, False, 50],
[True, False, 50],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 20],
[True, False, 50],
[False, False, 0],
[False, True, 0]]],
['regression: preset reached exactly',
[100, [[True, 30], [True, 50], [True, 50], [True, 10]]],
[[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]]],
['control: zero preset',
[0, [[False, 10], [True, 10], [False, 5], [True, 40]]],
[[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]]],
['regression: interrupted timing restarts',
[60, [[True, 40], [True, 40], [False, 40], [True, 40], [True, 40], [True, 40]]],
[[False, True, 0],
[False, True, 40],
[False, False, 0],
[False, True, 0],
[False, True, 40],
[True, False, 60]]],
['control: scenario 2',
[120, [[False, 0], [False, 75], [True, 75], [True, 0], [True, 0], [False, 75], [True, 60], [True, 40]]],
[[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 0],
[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, True, 40]]],
['control: scenario 3',
[50,
[[True, 40],
[False, 0],
[True, 60],
[True, 0],
[True, 40],
[True, 0],
[True, 0],
[False, 0],
[False, 50],
[False, 60],
[False, 10],
[True, 60]]],
[[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, True, 0],
[False, True, 40],
[False, True, 40],
[False, True, 40],
[False, False, 0],
[False, False, 0],
[False, False, 0],
[False, False, 0],
[False, True, 0]]],
['control: scenario 4',
[100, [[False, 60], [False, 20], [True, 75], [False, 25], [True, 60], [False, 25], [True, 40]]],
[[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0],
[False, True, 0]]]],
[['regression: scenario 1',
[0,
[[True, 10],
[True, 0],
[False, 50],
[True, 40],
[False, 20],
[False, 25],
[True, 50],
[True, 60],
[True, 40]]],
[[True, False, 0],
[True, False, 0],
[False, False, 0],
[True, False, 0],
[False, False, 0],
[False, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0]]],
['regression: scenario 3',
[120,
[[True, 60],
[True, 10],
[False, 10],
[True, 50],
[True, 20],
[True, 25],
[True, 25],
[False, 75],
[True, 40],
[True, 50],
[True, 75],
[True, 0]]],
[[False, True, 0],
[False, True, 10],
[False, False, 0],
[False, True, 0],
[False, True, 20],
[False, True, 45],
[False, True, 70],
[False, False, 0],
[False, True, 0],
[False, True, 50],
[True, False, 120],
[True, False, 120]]],
['regression: preset reached exactly',
[100, [[True, 30], [True, 50], [True, 50], [True, 10]]],
[[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]]],
['control: zero preset',
[0, [[False, 10], [True, 10], [False, 5], [True, 40]]],
[[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]]],
['regression: interrupted timing restarts',
[60, [[True, 40], [True, 40], [False, 40], [True, 40], [True, 40], [True, 40]]],
[[False, True, 0],
[False, True, 40],
[False, False, 0],
[False, True, 0],
[False, True, 40],
[True, False, 60]]],
['regression: long hold after done',
[50, [[True, 30], [True, 30], [True, 30], [True, 30], [False, 30]]],
[[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]]],
['control: scenario 2',
[100, [[False, 50], [True, 50], [True, 20], [False, 50], [True, 40], [True, 10], [False, 10]]],
[[False, False, 0],
[False, True, 0],
[False, True, 20],
[False, False, 0],
[False, True, 0],
[False, True, 10],
[False, False, 0]]],
['control: scenario 4',
[0, [[True, 25], [False, 75], [True, 20], [False, 25], [True, 20], [False, 25], [True, 40]]],
[[True, False, 0],
[False, False, 0],
[True, False, 0],
[False, False, 0],
[True, False, 0],
[False, False, 0],
[True, False, 0]]]],
[['regression: scenario 4',
[100,
[[False, 60],
[False, 0],
[True, 50],
[True, 20],
[True, 60],
[True, 20],
[True, 50],
[True, 0],
[True, 20],
[True, 0],
[True, 20],
[True, 25]]],
[[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 20],
[False, True, 80],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100]]],
['regression: scenario 5',
[100,
[[True, 20],
[True, 40],
[True, 20],
[True, 75],
[True, 50],
[True, 75],
[True, 0],
[True, 25],
[False, 50],
[False, 0],
[False, 40]]],
[[False, True, 0],
[False, True, 40],
[False, True, 60],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[False, False, 0],
[False, False, 0],
[False, False, 0]]],
['regression: preset reached exactly',
[100, [[True, 30], [True, 50], [True, 50], [True, 10]]],
[[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]]],
['control: zero preset',
[0, [[False, 10], [True, 10], [False, 5], [True, 40]]],
[[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]]],
['regression: interrupted timing restarts',
[60, [[True, 40], [True, 40], [False, 40], [True, 40], [True, 40], [True, 40]]],
[[False, True, 0],
[False, True, 40],
[False, False, 0],
[False, True, 0],
[False, True, 40],
[True, False, 60]]],
['regression: long hold after done',
[50, [[True, 30], [True, 30], [True, 30], [True, 30], [False, 30]]],
[[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]]],
['regression: scenario 1',
[120,
[[True, 0],
[True, 50],
[True, 50],
[True, 75],
[True, 75],
[False, 40],
[True, 25],
[False, 0],
[False, 10],
[True, 25],
[False, 0]]],
[[False, True, 0],
[False, True, 50],
[False, True, 100],
[True, False, 120],
[True, False, 120],
[False, False, 0],
[False, True, 0],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0]]],
['control: scenario 2',
[150, [[True, 50], [False, 40], [True, 20], [True, 20], [True, 10], [True, 40], [False, 50]]],
[[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, True, 20],
[False, True, 30],
[False, True, 70],
[False, False, 0]]]]]
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 fixture | Actual | Expected | Outcome |
|---|---|---|---|
| regression: preset reached exactly | [[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 110]] | [[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]] | Failed |
| regression: interrupted timing restarts | [[False, True, 0], [False, True, 40], [False, False, 0], [False, True, 0], [False, True, 40], [True, False, 80]] | [[False, True, 0], [False, True, 40], [False, False, 0], [False, True, 0], [False, True, 40], [True, False, 60]] | Failed |
| control: zero preset | [[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]] | [[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]] | Passed |
| regression: long hold after done | [[False, True, 0], [False, True, 30], [True, False, 60], [True, False, 80], [False, False, 0]] | [[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]] | Failed |
| regression: scenario 1 | [[False, True, 0], [False, False, 0], [False, True, 0], [False, False, 0], [False, False, 0], [False, True, 0], [False, True, 25], [True, False, 65]] | [[False, True, 0], [False, False, 0], [False, True, 0], [False, False, 0], [False, False, 0], [False, True, 0], [False, True, 25], [True, False, 30]] | Failed |
| regression: scenario 2 | [[False, False, 0], [False, True, 0], [False, True, 0], [False, True, 0], [False, True, 25], [True, False, 100], [True, False, 105]] | [[False, False, 0], [False, True, 0], [False, True, 0], [False, True, 0], [False, True, 25], [True, False, 30], [True, False, 30]] | Failed |
| control: scenario 3 | [[False, True, 0], [False, True, 20], [False, False, 0], [False, True, 0], [False, True, 0], [False, False, 0], [False, True, 0]] | [[False, True, 0], [False, True, 20], [False, False, 0], [False, True, 0], [False, True, 0], [False, False, 0], [False, True, 0]] | Passed |
| regression: scenario 4 | [[True, False, 0], [False, False, 0], [True, False, 0], [True, False, 20], [True, False, 40], [True, False, 20], [True, False, 75], [True, False, 0], [True, False, 10]] | [[True, False, 0], [False, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0]] | Failed |
SHA-256 / 46a1e7272609cb364afd8014a929f7b7acbfb657ec1bad828a3eb726c3213a16
3 / The verified repair
Exit 0"""Failure Map reference implementation. Python standard library only."""
import json
N = 1
observations = []
def solve(preset, scans):
acc = 0
prev = False
out = []
for rung_in, dt in scans:
rung_in = bool(rung_in)
if rung_in and prev:
acc = min(preset, acc + dt)
elif not rung_in:
acc = 0
dn = rung_in and acc >= preset
tt = rung_in and not dn
prev = rung_in
out.append([dn, tt, acc])
return out
def check(label, actual, expected):
observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['regression: preset reached exactly',
[100, [[True, 30], [True, 50], [True, 50], [True, 10]]],
[[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]]],
['regression: interrupted timing restarts',
[60, [[True, 40], [True, 40], [False, 40], [True, 40], [True, 40], [True, 40]]],
[[False, True, 0],
[False, True, 40],
[False, False, 0],
[False, True, 0],
[False, True, 40],
[True, False, 60]]],
['control: zero preset',
[0, [[False, 10], [True, 10], [False, 5], [True, 40]]],
[[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]]],
['regression: long hold after done',
[50, [[True, 30], [True, 30], [True, 30], [True, 30], [False, 30]]],
[[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]]],
['regression: scenario 1',
[30, [[True, 40], [False, 75], [True, 60], [False, 25], [False, 10], [True, 60], [True, 25], [True, 40]]],
[[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 25],
[True, False, 30]]],
['regression: scenario 2',
[30, [[False, 25], [True, 50], [True, 0], [True, 0], [True, 25], [True, 75], [True, 75]]],
[[False, False, 0],
[False, True, 0],
[False, True, 0],
[False, True, 0],
[False, True, 25],
[True, False, 30],
[True, False, 30]]],
['control: scenario 3',
[120, [[True, 25], [True, 20], [False, 75], [True, 75], [True, 0], [False, 10], [True, 25]]],
[[False, True, 0],
[False, True, 20],
[False, False, 0],
[False, True, 0],
[False, True, 0],
[False, False, 0],
[False, True, 0]]],
['regression: scenario 4',
[0,
[[True, 10],
[False, 25],
[True, 25],
[True, 20],
[True, 40],
[True, 20],
[True, 75],
[True, 0],
[True, 10]]],
[[True, False, 0],
[False, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0]]]],
[['regression: interrupted timing restarts',
[60, [[True, 40], [True, 40], [False, 40], [True, 40], [True, 40], [True, 40]]],
[[False, True, 0],
[False, True, 40],
[False, False, 0],
[False, True, 0],
[False, True, 40],
[True, False, 60]]],
['regression: long hold after done',
[50, [[True, 30], [True, 30], [True, 30], [True, 30], [False, 30]]],
[[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]]],
['regression: preset reached exactly',
[100, [[True, 30], [True, 50], [True, 50], [True, 10]]],
[[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]]],
['control: zero preset',
[0, [[False, 10], [True, 10], [False, 5], [True, 40]]],
[[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]]],
['regression: scenario 1',
[0,
[[True, 40],
[True, 10],
[True, 10],
[False, 10],
[True, 20],
[True, 25],
[True, 20],
[False, 25],
[True, 20]]],
[[True, False, 0],
[True, False, 0],
[True, False, 0],
[False, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0],
[False, False, 0],
[True, False, 0]]],
['control: scenario 2',
[150,
[[True, 60],
[True, 10],
[False, 20],
[False, 40],
[True, 50],
[True, 25],
[False, 25],
[False, 75],
[True, 25],
[False, 0],
[True, 60],
[False, 10]]],
[[False, True, 0],
[False, True, 10],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 25],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0]]],
['regression: scenario 3',
[50,
[[False, 50],
[True, 75],
[True, 75],
[True, 20],
[True, 75],
[True, 0],
[False, 60],
[True, 25],
[False, 10]]],
[[False, False, 0],
[False, True, 0],
[True, False, 50],
[True, False, 50],
[True, False, 50],
[True, False, 50],
[False, False, 0],
[False, True, 0],
[False, False, 0]]],
['regression: scenario 4',
[120,
[[True, 75],
[False, 60],
[True, 20],
[True, 25],
[False, 40],
[False, 40],
[True, 50],
[True, 60],
[True, 75],
[True, 40],
[True, 0]]],
[[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, True, 25],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 60],
[True, False, 120],
[True, False, 120],
[True, False, 120]]]],
[['regression: long hold after done',
[50, [[True, 30], [True, 30], [True, 30], [True, 30], [False, 30]]],
[[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]]],
['regression: scenario 1',
[50,
[[True, 75],
[True, 40],
[True, 60],
[True, 0],
[True, 25],
[False, 50],
[False, 75],
[True, 60],
[True, 20],
[True, 60],
[False, 60],
[True, 75]]],
[[False, True, 0],
[False, True, 40],
[True, False, 50],
[True, False, 50],
[True, False, 50],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 20],
[True, False, 50],
[False, False, 0],
[False, True, 0]]],
['regression: preset reached exactly',
[100, [[True, 30], [True, 50], [True, 50], [True, 10]]],
[[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]]],
['control: zero preset',
[0, [[False, 10], [True, 10], [False, 5], [True, 40]]],
[[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]]],
['regression: interrupted timing restarts',
[60, [[True, 40], [True, 40], [False, 40], [True, 40], [True, 40], [True, 40]]],
[[False, True, 0],
[False, True, 40],
[False, False, 0],
[False, True, 0],
[False, True, 40],
[True, False, 60]]],
['control: scenario 2',
[120, [[False, 0], [False, 75], [True, 75], [True, 0], [True, 0], [False, 75], [True, 60], [True, 40]]],
[[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 0],
[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, True, 40]]],
['control: scenario 3',
[50,
[[True, 40],
[False, 0],
[True, 60],
[True, 0],
[True, 40],
[True, 0],
[True, 0],
[False, 0],
[False, 50],
[False, 60],
[False, 10],
[True, 60]]],
[[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, True, 0],
[False, True, 40],
[False, True, 40],
[False, True, 40],
[False, False, 0],
[False, False, 0],
[False, False, 0],
[False, False, 0],
[False, True, 0]]],
['control: scenario 4',
[100, [[False, 60], [False, 20], [True, 75], [False, 25], [True, 60], [False, 25], [True, 40]]],
[[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0],
[False, True, 0]]]],
[['regression: scenario 1',
[0,
[[True, 10],
[True, 0],
[False, 50],
[True, 40],
[False, 20],
[False, 25],
[True, 50],
[True, 60],
[True, 40]]],
[[True, False, 0],
[True, False, 0],
[False, False, 0],
[True, False, 0],
[False, False, 0],
[False, False, 0],
[True, False, 0],
[True, False, 0],
[True, False, 0]]],
['regression: scenario 3',
[120,
[[True, 60],
[True, 10],
[False, 10],
[True, 50],
[True, 20],
[True, 25],
[True, 25],
[False, 75],
[True, 40],
[True, 50],
[True, 75],
[True, 0]]],
[[False, True, 0],
[False, True, 10],
[False, False, 0],
[False, True, 0],
[False, True, 20],
[False, True, 45],
[False, True, 70],
[False, False, 0],
[False, True, 0],
[False, True, 50],
[True, False, 120],
[True, False, 120]]],
['regression: preset reached exactly',
[100, [[True, 30], [True, 50], [True, 50], [True, 10]]],
[[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]]],
['control: zero preset',
[0, [[False, 10], [True, 10], [False, 5], [True, 40]]],
[[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]]],
['regression: interrupted timing restarts',
[60, [[True, 40], [True, 40], [False, 40], [True, 40], [True, 40], [True, 40]]],
[[False, True, 0],
[False, True, 40],
[False, False, 0],
[False, True, 0],
[False, True, 40],
[True, False, 60]]],
['regression: long hold after done',
[50, [[True, 30], [True, 30], [True, 30], [True, 30], [False, 30]]],
[[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]]],
['control: scenario 2',
[100, [[False, 50], [True, 50], [True, 20], [False, 50], [True, 40], [True, 10], [False, 10]]],
[[False, False, 0],
[False, True, 0],
[False, True, 20],
[False, False, 0],
[False, True, 0],
[False, True, 10],
[False, False, 0]]],
['control: scenario 4',
[0, [[True, 25], [False, 75], [True, 20], [False, 25], [True, 20], [False, 25], [True, 40]]],
[[True, False, 0],
[False, False, 0],
[True, False, 0],
[False, False, 0],
[True, False, 0],
[False, False, 0],
[True, False, 0]]]],
[['regression: scenario 4',
[100,
[[False, 60],
[False, 0],
[True, 50],
[True, 20],
[True, 60],
[True, 20],
[True, 50],
[True, 0],
[True, 20],
[True, 0],
[True, 20],
[True, 25]]],
[[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, True, 20],
[False, True, 80],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100]]],
['regression: scenario 5',
[100,
[[True, 20],
[True, 40],
[True, 20],
[True, 75],
[True, 50],
[True, 75],
[True, 0],
[True, 25],
[False, 50],
[False, 0],
[False, 40]]],
[[False, True, 0],
[False, True, 40],
[False, True, 60],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[True, False, 100],
[False, False, 0],
[False, False, 0],
[False, False, 0]]],
['regression: preset reached exactly',
[100, [[True, 30], [True, 50], [True, 50], [True, 10]]],
[[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]]],
['control: zero preset',
[0, [[False, 10], [True, 10], [False, 5], [True, 40]]],
[[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]]],
['regression: interrupted timing restarts',
[60, [[True, 40], [True, 40], [False, 40], [True, 40], [True, 40], [True, 40]]],
[[False, True, 0],
[False, True, 40],
[False, False, 0],
[False, True, 0],
[False, True, 40],
[True, False, 60]]],
['regression: long hold after done',
[50, [[True, 30], [True, 30], [True, 30], [True, 30], [False, 30]]],
[[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]]],
['regression: scenario 1',
[120,
[[True, 0],
[True, 50],
[True, 50],
[True, 75],
[True, 75],
[False, 40],
[True, 25],
[False, 0],
[False, 10],
[True, 25],
[False, 0]]],
[[False, True, 0],
[False, True, 50],
[False, True, 100],
[True, False, 120],
[True, False, 120],
[False, False, 0],
[False, True, 0],
[False, False, 0],
[False, False, 0],
[False, True, 0],
[False, False, 0]]],
['control: scenario 2',
[150, [[True, 50], [False, 40], [True, 20], [True, 20], [True, 10], [True, 40], [False, 50]]],
[[False, True, 0],
[False, False, 0],
[False, True, 0],
[False, True, 20],
[False, True, 30],
[False, True, 70],
[False, False, 0]]]]]
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 fixture | Actual | Expected | Outcome |
|---|---|---|---|
| regression: preset reached exactly | [[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]] | [[False, True, 0], [False, True, 50], [True, False, 100], [True, False, 100]] | Passed |
| regression: interrupted timing restarts | [[False, True, 0], [False, True, 40], [False, False, 0], [False, True, 0], [False, True, 40], [True, False, 60]] | [[False, True, 0], [False, True, 40], [False, False, 0], [False, True, 0], [False, True, 40], [True, False, 60]] | Passed |
| control: zero preset | [[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]] | [[False, False, 0], [True, False, 0], [False, False, 0], [True, False, 0]] | Passed |
| regression: long hold after done | [[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]] | [[False, True, 0], [False, True, 30], [True, False, 50], [True, False, 50], [False, False, 0]] | Passed |
| regression: scenario 1 | [[False, True, 0], [False, False, 0], [False, True, 0], [False, False, 0], [False, False, 0], [False, True, 0], [False, True, 25], [True, False, 30]] | [[False, True, 0], [False, False, 0], [False, True, 0], [False, False, 0], [False, False, 0], [False, True, 0], [False, True, 25], [True, False, 30]] | Passed |
| regression: scenario 2 | [[False, False, 0], [False, True, 0], [False, True, 0], [False, True, 0], [False, True, 25], [True, False, 30], [True, False, 30]] | [[False, False, 0], [False, True, 0], [False, True, 0], [False, True, 0], [False, True, 25], [True, False, 30], [True, False, 30]] | Passed |
| control: scenario 3 | [[False, True, 0], [False, True, 20], [False, False, 0], [False, True, 0], [False, True, 0], [False, False, 0], [False, True, 0]] | [[False, True, 0], [False, True, 20], [False, False, 0], [False, True, 0], [False, True, 0], [False, False, 0], [False, True, 0]] | Passed |
| regression: scenario 4 | [[True, False, 0], [False, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0]] | [[True, False, 0], [False, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0], [True, False, 0]] | Passed |
SHA-256 / 36acc3f62d6207f146fdc136dbd6a97ddb5c89ed07232f6b8ff1c3b04269023e
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 2026-09-29T14:51:39.773639+00:00.
Case digest / 9367437c8fbe5ee3d1abee765b42744d29ebab90ab1fde6dc17a644b41b93580