STM32 6LoWPAN Stack Integration

I need a complete 6LoWPAN implementation running on an STM32 based node that will be used in automated control systems. The radio transceiver module already embeds the IEEE 802.15.4 PHY and MAC, so your work starts at the adaptation layer upward: building, porting, or custom-writing the 6LoWPAN stack, exposing an easy-to-use API for my application code, and demonstrating reliable mesh communication between multiple nodes in the field.

Hardware
• Microcontroller: I can work with any Cortex-M0/M1/M2/M3/M4 device, so feel free to target the STM32F0, F4, L4, or whichever family you find most power- and memory-efficient for the stack.
• Radio: external module with integrated PHY/MAC; SPI or UART host interface is available and fully documented.

Scope of work
1. Port or develop the 6LoWPAN adaptation layer plus UDP/CoAP support on top of the chosen STM32 HAL/LL drivers.
2. Write the driver layer that bridges the stack to the radio’s command set.
3. Expose a concise C API so that my control firmware can send/receive sensor data and actuation commands without touching the low-level networking code.
4. Deliver a proof-of-concept demo: at least two nodes exchanging commands that toggle a GPIO-controlled actuator, showing the low-power operation profile.
5. Provide build scripts and documentation so I can reproduce the firmware with GCC or STM32CubeIDE.

Acceptance criteria
• Packet loss < 1 % at 50 m line-of-sight.
• End-to-end latency < 150 ms for a command message.
• Average current consumption in sleep < 15 µA (measured with the radio in idle).
• Source code compiles with ​–O3 and no warnings.

If you already have experience with Contiki-NG, Zephyr, or RIOT-OS 6LoWPAN ports on STM32, let me know—leveraging an existing codebase is fine as long as licence terms remain permissive (BSD, Apache 2.0, etc.). I’ll be available for rapid hardware testing and will supply schematics and pin maps on day one.