{"type":"doc","content":[{"type":"paragraph","content":[{"type":"text","text":"After 10+ years bridging embedded C into cross-platform mobile apps, I see the same three mistakes kill projects before they ship. Here's what to watch for — and how to fix each one."}]},{"type":"heading","attrs":{"level":2},"content":[{"type":"text","text":"Mistake #1: Blocking the Plugin Thread"}]},{"type":"paragraph","content":[{"type":"text","text":"Most firmware engineers treat the Capacitor plugin bridge like a synchronous function call. They write blocking reads on UART or SPI directly inside the plugin method, freezing the main thread. On Android this triggers an ANR (Application Not Responding) dialog. On iOS, the watchdog kills your app."}]},{"type":"paragraph","content":[{"type":"text","marks":[{"type":"bold"}],"text":"The fix:"},{"type":"text","text":" Always dispatch hardware I/O to a background thread (or RTOS task) and use async callbacks or promises to return data to the JS layer. Design your wire protocol to be non-blocking from day one."}]},{"type":"heading","attrs":{"level":2},"content":[{"type":"text","text":"Mistake #2: Ignoring Memory Ownership Across the Bridge"}]},{"type":"paragraph","content":[{"type":"text","text":"In bare-metal C, you own every byte. But when you pass a buffer from C → JNI → Java → Capacitor → JavaScript, ownership gets murky. I've seen engineers malloc a buffer in C, pass the pointer through JNI, and then free it before Java is done reading — instant segfault, but only under load."}]},{"type":"paragraph","content":[{"type":"text","marks":[{"type":"bold"}],"text":"The fix:"},{"type":"text","text":" Establish a clear ownership contract. Copy data at the boundary (C→Java or C→Swift), then free on the C side immediately. Yes, the copy costs cycles — but it costs far less than debugging a use-after-free that only reproduces on one specific Android device."}]},{"type":"heading","attrs":{"level":2},"content":[{"type":"text","text":"Mistake #3: Treating the Mobile App Like a Debug Terminal"}]},{"type":"paragraph","content":[{"type":"text","text":"Firmware devs love dumping raw hex over serial. So when they build a mobile plugin, they stream raw binary frames to JavaScript and try to parse them in TypeScript. This works in a prototype. It falls apart in production when you need error recovery, back-pressure, and reconnection logic."}]},{"type":"paragraph","content":[{"type":"text","marks":[{"type":"bold"}],"text":"The fix:"},{"type":"text","text":" Design a proper application-layer protocol with message framing, sequence numbers, and CRC checks. Handle flow control in the RTOS task, not in the UI layer. Your mobile app should receive clean, typed data objects — not byte arrays."}]},{"type":"heading","attrs":{"level":2},"content":[{"type":"text","text":"Want the full system?"}]},{"type":"paragraph","content":[{"type":"text","text":"I teach the complete pipeline — from RTOS task design through HAL abstraction, JNI/Swift bridging, wire protocol engineering, and production plugin publishing — in my course. If you're serious about shipping native plugins that don't crash in the field, check it out."}]}]}