S5 AWL Command: SPBN (Jump if NOT)
S5 AWL instruction SPBN: Jump to label if VKE is FALSE. The inverse of SPB.
S5 AWL Command: SPBN (Jump if NOT)
SPBN jumps to a label only if the VKE is FALSE. It is the inverse of SPB. Useful for "skip this section when condition is not met" patterns.
Syntax
U E 0.0
SPBN =M001 // Jump to M001 if E 0.0 is FALSE
// ... code that only runs when E 0.0 is TRUE ...
M001: NOP 0
S7 Equivalent
| S5 AWL | S7 STL | S7 SCL |
|---|---|---|
SPBN =M001 | JCN M001 (EN) / SPBN M001 (DE) | IF NOT condition THEN ... |
Typical Use — Guard Clause
U E 0.0 // Mode selector
SPBN =SKIP // If not in this mode, skip entire section
// ... mode-specific code ...
SKIP: NOP 0
This is cleaner than SPB for "skip" patterns because you avoid an extra SPA.
Related: SPB (Jump if TRUE) | SPA (Unconditional)
Part of the S5 AWL Command Reference. Maintained by PLCcheck.ai.
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