Start from the library
Open Library and pick a bundled device — a 48-pin MCU, a small two-bank FPGA, a 40-pin GPIO header, or a board connector — or create a new project. The app is fully usable offline the moment it launches.
Read the board
Open Board to see the device summary and the interactive pin-map grid. Tap a pin to inspect its physical designator, IO bank and voltage domain, and its capabilities.
Define signals
Open Signals and add each logical signal you need to route. Give it a required capability, such as UART or ADC, and set the differential flag when it is one half of a P/N pair.
Assign to pins
Assign a signal to a compatible pin from the grid, or choose Auto-assign to place all remaining signals deterministically on compatible free pins while honoring bank and voltage rules.
Review the checks
Open Checks for the live design-rule report. Severities cover double-assignment, capability mismatch, power and no-connect misuse, bank voltage conflict, differential-pair validity, bank capacity, reserved-pin protection, and completeness.
Export a pin map
Export a text pin map and net list through Apple's system share sheet and choose where it goes. Everything else stays in the app's local container.
Local data
Projects save automatically on the device. Logichart has no login or sync service. Device backups and exported files are controlled through Apple and the destinations you choose.
Before contacting support
Include the device model, iOS or iPadOS version, Logichart version, the screen involved, and reproducible steps. You do not need to share your project file unless you deliberately choose to.
Frequently asked
Does Logichart need an account or the internet? No. There is no sign-in and no network connection. Every feature runs offline.
Are the bundled devices real parts? No. They are authored, illustrative example devices, not authoritative models of any specific manufacturer part.
Why did Auto-assign leave a signal unplaced? The first-fit assigner only uses compatible free pins that satisfy bank and voltage rules. If none remain, the signal stays unplaced and appears in the completeness check.
Will the same plan always give the same result? Yes. Auto-assign and the checks are deterministic, with no randomness and no network, so a given plan always produces the same output.
Is there an in-app purchase or subscription? No. The paid download includes the full tool, with no ads, in-app purchases, or subscriptions.
Boundary
Logichart is a planning and documentation aid, not an electrical sign-off tool. It does not replace the manufacturer datasheet, a vendor pin-mux tool such as STM32CubeMX, Vivado, or Quartus, timing or signal-integrity analysis, or a board-level ERC/DRC. Verify every assignment against the official datasheet before committing a design.