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# Embedded Firmware Engineer - Cortex-M, CAN/Modbus

- **Company:** ERNI
- **Location:** Spain
- **Contract:** Permanent contract
- **Skills:** ARM Architecture, Embedded Software, Firmware, Modbus, Universal Asynchronous Receiver/Transmitter, Test-Driven Development (TDD), Bare Metal
- **Published:** November 3, 2026
- **Apply:** https://www.jobleads.com/es/job/embedded-firmware-engineer-cortex-m-can-modbus--comunidad-valenciana--e8183465689195eff11fb7b8760dc789d

## About the Role

The role sits at the electronics/software intersection with a hybrid office model. English fluency is required; German is a plus. Prior STM32CubeIDE/HAL/LL experience is beneficial.

## Description

ERNI in Spain seeks an Embedded Firmware Engineer to design, develop and maintain bare-metal firmware for ARM Cortex-M MCUs, mainly STM32. You will connect sensors and host systems using CAN, Modbus, UART, I²C and SPI, contributing to hardware decisions and test-driven development.

The role sits at the electronics/software intersection with a hybrid office model. English fluency is required; German is a plus. Prior STM32CubeIDE/HAL/LL experience is beneficial.