lwip-integration

# lwIP Integration ## Overview Use this skill to integrate lwIP by separating hardware Ethernet/Wi-Fi drivers, `netif` glue, memory pools, threading model, and protocol configuration. A successful port proves link, IP configuration, packet RX/TX, and resource stability under load. ## When To Use Use this skill when: - The user wants to add or debug lwIP on bare metal, FreeRTOS, RT-Thread, Zephyr, vendor SDKs, or custom network drivers. - The issue involves `lwipopts.h`, `sys_arch`, `netif`, DHCP, TCP/UDP, pbufs, memory pools, packet loss, or hard faults in networking. - The target uses Ethernet, Wi-Fi, PPP, SLIP, or a vendor network interface. Do not use this skill when the physical link or board interface is not proven. Use `hardware-interface-debug` first for PHY, RMII/MII, clocks, or wiring issues. For FreeRTOS-native TCP/IP, use `freertos-plus-tcp-integration`. For MQTT over lwIP, use `mqtt-embedded-integration` after basic connectivity works. ## First Questions Ask for: - MCU/SoC, network interface, PHY/module, RTOS, and lwIP version. - Driver source: vendor SDK, custom MAC driver, Wi-Fi module, or simulator. - Threading model: NO_SYS raw API, tcpip_thread, socket/netconn API, or RTOS integration. - `lwipopts.h`, memory sizes, pbuf pool settings, and enabled protocols. - Current symptom: no link, no IP, DHCP timeout, ping fails, TCP stalls, memory exhaustion, or crash. - Packet/log evidence: link status, IP address, ARP, ping, Wireshark, counters, or asserts. #...