June 1, 2026 — Article 16 of the Studying SIMATIC AX series. The current tested SIMATIC AX ST compiler rejects general TRY/CATCH, so expected PLC fault conditions still need deterministic guard/report/recover logic, safe defaults, and alarm/status reporting.
May 11, 2026 — How SIMATIC AX organizes variables and types for TIA Portal engineers — VAR_INPUT/VAR_OUTPUT/VAR sections, VAR_GLOBAL and VAR_EXTERNAL contracts, STRUCT and ENUM patterns, typed literals, and the AT keyword for direct addresses. A practical mapping from TIA Portal mental models to AX text.