DigiTekXplorer - abDraw

 Ports sit on block edges — ordered, grid-aligned, per side. Wires bind to a specific named pin and stay attached through every move and resize. 

 Any wire with a pinned end is owned by the router and rebuilt on every move, entering and exiting pins perpendicular to the edge with staggered channels so fans never overlap.

 Drag blue waypoint handles, double-click to insert, slide mid-segments — hand routes are honored as drawn and only released back to the router when a connected block moves. 

Muxes (N inputs, binary-labeled sel), registers with D/Q/clk and a clock triangle, adders, and rotatable off-page connectors — placed as first-class parametric blocks. 

Mark a wire as a bus, tap a bit range like [7:0], and get automatic junction dots wherever three or more ends meet or a T-junction lands on a segment. 

Same net name means the same net — highlighted in blue — and off-page connectors carry a node across sheets so a design can span many pages. 

Sheet tabs to add, rename, delete and switch; per-sheet title blocks and page sizes (Letter, Legal, Tabloid, ANSI, A-series or custom) on a scrollable pasteboard. 

Union-find netlist extraction across all sheets exports a .net file, and Validate Schematic rings every unconnected pin in red. 

Marquee-select and move groups with pinned-endpoint handling, plus non-electrical note arrows, dashed note lines, aligned text and shape fill for documentation. 

 Export a sheet or every sheet to PNG, a sheet to PDF, or the whole package as a multi-page PDF — PIL-only, reusing the exact on-screen geometry.