A Tiny Embedded UDP/IP Stack Implementation for FreeRTOS

FreeRTOS+UDP is a small, fully thread aware, sockets based, and very efficient UDP/IP (IPv4) stack for FreeRTOS. It was created specifically for, and contains the features needed by, our new Internet of Things solution (currently being documented). The standard Berkeley sockets “like” interface makes it fast to learn and easy to use in other applications, and its compact size and efficiency makes it ideal for communication between small network enabled embedded devices.


Berkeley sockets like API
Standard and zero copy interfaces
Fully re-entrant and thread aware API
Tiny code size
Includes ARP, DHCP and DNS
Supports incoming and outgoing pings
Outgoing packet fragmentation
Tightly integrated with FreeRTOS
Open source or commercial licensing
Berkeley Like Sockets API


Code Size (example generated with GCC for ARM Cortex-M)
Feature With -O1 Optimisation With -Os Optimisation
Base UDP/IP stack 3.6K 2.9K
…with processing of incoming pings enabled 3.7K 3.3K
…with outgoing pings and processing of ping replies enabled 4K 3.2K
…with fragmentation of outgoing packets enabled 4K 3.2
…with auto configuration via DHCP enabled 5.5K 4.2K
…with domain name lookup via DNS enabled 4.4K 3.5K
…with everything enabled 6.7K 5.1K


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Latest News

FreeRTOS v10.2.1 is available for immediate download. MIT licensed, includes 64-bit RISC-V, NXP Cortex-M33 demo & Nuvoton Cortex-M23 demo & STM32H745 dual core (AMP) demo.

New Updates to MIT licensed IoT MQTT and POSIX libraries are now available. New library IoT HTTPS is available.  Includes demo projects.

View a recording of the “OTA Update Security and Reliability” webinar, presented by TI and AWS.


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