Free Build Sandbox

Your goal

• Build anything. Drop a contact on a rung and a coil at the right hand end, press Run, then force the inputs in the I/O panel and watch the power flow live.
• Every instruction the controller has is in the toolbox: rising and falling edge one-shots, the six compares (=, not equal, >, >=, <, <=) against a constant or another tag, LIM for a range, TON, TOF and RTO, CTU, CTD and CTUD, RES, and MOV, CLR, ADD, SUB, MUL, DIV, MOD and CPT.
• Add your own tags, timers, counters and number registers from the toolbox or any tag menu ("+ New..."), and split a long program into routines with JSR.
• Check my program reads your rungs back as a machine and runs them for four simulated minutes, so it can tell you what will never move rather than only what will not load.
• Or describe the machine in plain English and let the AI write it, then read the walkthrough it comes with.
• Everything autosaves in this browser. History keeps the recent versions, and Share or Export turns the program into a link or an image.