comb and (graphical LD twin)¶


suite id	`g_comb_and`
domain	manufacturing
language	LD-graphical
difficulty	easy
validation status	validated
origin	authored
license	CC-BY-4.0
syntax pair of	`ld_comb_and`

Graphical PLCopen XML twin of the K-LD textual benchmark (syntax-coverage pair)

What is proved¶

From benchmarks/manufacturing/g_comb_and/props.yaml. What each kind claims, and what it becomes on either route, is on The properties we prove.

id	kind	claim	requirement
`P1`	`invariant`	`!Y \|\| (A && B && C)`	Output Y is energised only when all series contacts A, B and C are closed.

Variants¶

file	expected verdict	violates	method
`program.xml`	SAFE	none	expert

Files¶

file	what it is	size	sha256
`benchmark.yml`	benchmark metadata	0.6 KB	`745e34f5f8e6`
`program.xml`	ladder program, PLCopen XML	2.1 KB	`a62808ceb550`
`props.yaml`	property file	0.2 KB	`7f98094eb39c`

Structured text, derived¶

Read off the ladder graph by runner/ld_to_st.py: every rung's contacts and coils rewritten as IEC 61131-3 assignments, in the same series/parallel logic the PLCopen XML encodes. This is a reading aid, not a second source of expected verdicts; ESBMC verifies the ladder program shown above, never this rendering.

program.xml

PROGRAM g_comb_and
VAR_INPUT
    A : BOOL;
    B : BOOL;
    C : BOOL;
END_VAR

VAR_OUTPUT
    Y : BOOL;
END_VAR


Y := ((A AND B) AND C);

END_PROGRAM

Recorded runs¶

A task can carry two routes. ld is ESBMC's ladder front end reading the program directly. via C is the same solver reached through Beremiz and MatIEC, which is the only route that reaches ST, IL, FBD and SFC; see How ESBMC-PLC works.

comb_and (props.yaml, expected SAFE): master SAFE
comb_and_ld_viac via C (props.yaml, expected SAFE): master SAFE