Embedded Hardware/PCB & Firmware Engineer Required-Kolkata

We are looking for an experienced freelance Embedded Hardware + PCB + Firmware Engineer for an IoT/industrial electronics project. Location: Kolkata preferred Required hands-on experience: • STM32 Nucleo / Discovery boards • Embedded C/C++ and STM32 firmware • UART / USART / RS485 / Modbus RTU • USB-to-RS485 & UART-to-RS485 • GSM / 4G / LTE modules and AT commands • PCB schematic & layout – KiCad / Altium / Eagle / EasyEDA • Component selection & BOM preparation • Power supply and protection circuits • Logic analyzer / oscilloscope / multimeter • PCB bring-up, debugging and hardware testing • Sensor and industrial interface integration • ADC / 4–20mA / 0–2V interfaces Good to have: ESP32, MQTT, LoRa, FreeRTOS, CAN, BLE/Wi-Fi and industrial IoT experience. Engagement: Project-based initially, with possibility of long-term collaboration. We are specifically looking for someone who is hands-on with hardware and can independently troubleshoot a PCB—not only firmware/software development. Please share: CV/Profile Previous PCB/IoT projects STM32 experience PCB designs/portfolio Availability Expected hourly/project rate Kolkata location