Firmware Engineer

As a Senior Firmware Engineer, you will aid in the design, development, and maintenance of embedded firmware across a range of CEM Systems hardware platforms. You will work closely with hardware, software, and systems teams to deliver reliable, secure, and high-performance solutions used globally in critical infrastructure, airports, data centres, and enterprise environments. This is a hands-on technical position involving firmware design, secure solution development, problem-solving, and full product lifecycle support., * Design, implement and support firmware for embedded systems using RTOS-based environments.

• Develop/maintain/debug multi threaded firmware applications using signals, semaphores, mailboxes, and other RTOS primitives to manage constrained resources.
• Create clear, robust finite state machine logic for deterministic device behaviour.
• Implement internal communication protocols including SPI, I²C, and other MCU subsystems.
• Design for Security - develop firmware with latest cyber security practices at the core

Networking & Security Protocols

• Develop and maintain embedded networking features using the ISO model, including TCP/IP, routing, subnets, client/server operation.
• Integrate secure communication technologies including TLS (MBED, WolfSSL) and modern cipher suites such as AES, CHACHA20 along with SHA.
• Work with access-control-specific communication standards, including OSDP for control panels and peripheral devices.

• Ability to work in the office three days per week
• Authorization to work in the UK
• Proven experience designing firmware for embedded systems (ideally real-time / resource-constrained environments).
• Strong proficiency in C, familiarity with C++ and JAVA is desirable.
• Experience with a range od IDEs including Keil uVision, QT Creator, Android Studio and source control systems including Github and TFS
• Experience with embedded Linux and Android operating systems desirable along with
• Solid understanding of hardware fundamentals and microcontroller architectures.
• Demonstrable experience with networking stacks and secure communication protocols.
• Experience with smart-card or RFID technologies is a significant advantage.
• Excellent analytical and debugging abilities, including use of oscilloscopes, logic analysers, and protocol tools.
• Ability to work autonomously and collaboratively across multidisciplinary teams.
• Familiarity with Mitsubishi PLCs desirable.

Desirable Experience

• Experience in access control, security systems, or other safety-critical embedded environments.
• Previous leadership/mentoring responsibilities.
• Familiarity with compliance, certification, or regulated environments.

• Implement and support smart-card reader technologies across ISO 14443A/B, ISO 15693, and related RFID standards.
• Work with DESFire architecture, including AES and 3DES encryption modes, application identifiers (AIDs), and file structures.
• Support legacy and proprietary card formats including MIFARE Classic, HID iClass, and customer-specific technologies.

Electronics & Hardware Interaction

• Read, interpret, and collaborate using circuit diagrams and system schematics.
• Understand power supply behaviour, electrical limitations, and protection considerations.
• Work with RS485 asynchronous communications, Ethernet hardware, NFC antenna systems, relays, and FET-based output drivers.

Problem Solving & Technical Leadership

• Conduct root-cause analysis across multi-component systems-both hardware and firmware.
• Develop solutions that minimise collateral impact and maintain system stability.
• Mentor junior engineers, perform code reviews, and contribute to engineering best practice.