LightWeight IP (lwIP)

Written in November 07, 2025

2025   ·   TIL

Lightweight IP

Lighweight IP stack (“lwIP”1) is a small independent implementation of the TCP/IP protocol suite, mainly designed for embedded systems. 2

STM32 and lwIP

  • STM32 board with Ethernet compatibility can be connected to the internet.
  • STM32 Ethernet Library is based on lwIP.
  • For example, STM32F767G Discovery board supports Ethernet communication by PHY (= physcial layer device) LAN8742A-CZ-TR and RJ45 jack. Some STM32 boards do not support Ethernet, and even STM32F7 boards that are not Discovery kit require a external PHY device for Ethernet.
LAN8742A-CZ-TR
RJ45 connector (example)

References

  1. https://github.com/stm32duino/LwIP?tab=readme-ov-file ↩

  2. https://www.nongnu.org/lwip/2_1_x/index.html ↩