Worked on maintenance and reliability improvements for the Zephyr project, focusing on embedded systems and hardware interfacing using C programming. Addressed a critical issue in the zephyrproject-rtos/zephyr repository by correcting the ARDUINO_NANO_HEADER_A3 pin mapping, which previously conflicted with ARDUINO_NANO_HEADER_A5. This fix involved updating the relevant header file to resolve a pin-number typo, ensuring accurate Arduino Nano pin assignments and preventing hardware integration errors. Documented the change thoroughly in the commit history to support future maintenance. The work enhanced cross-board compatibility, reduced the risk of misconfiguration, and contributed to more stable builds for Arduino Nano configurations.