Honeywell embedded interview prep

Roles they hire for

• Building controls firmware engineer
• Process automation engineer
• Aerospace software engineer

What they emphasise

• Building controls
• Process automation
• Aerospace (DO-178C)

Brush up on

BACnetModbusDO-178C basicsWireless sensorsSafety

How the rounds usually run

A typical regulated product loop for embedded roles. Companies vary by team and seniority.

Recruiter or hiring-manager screen

• Background in regulated or safety-critical work
• Role fit

Example: Have you worked under a formal development process? Which one?

Technical 1: C, RTOS and state machines

• Embedded C and RTOS fundamentals
• State machine design and implementation

Example: Implement a table-driven state machine in C and explain how you'd test every transition.

Technical 2: Safety and design

• Fault detection, safe states and recovery
• Risk analysis and software FMEA
• Verification and traceability

Example: How would you detect a stuck sensor reading?

Panel: cross-functional

• Working with systems, hardware and quality engineers
• Handling changes under change control

Example: A hardware change lands late. How do you assess its impact on certified firmware?

HR

• Motivation and values
• Logistics

Example: Why do you want to work on medical or industrial devices?

Practice questions

Original questions written for Honeywell's focus areas, not leaked ones.

1. How does BACnet represent a temperature sensor and its setpoint?
2. Design a wireless sensor that reports reliably through concrete walls.
3. What does DO-178C require that ordinary development doesn't?
4. How do you keep a controller safe if its network link drops?
5. Explain how you'd test firmware against many third-party devices on a building network.

Your prep playlist

Design rounds to practise

Themes are inferred from Honeywell's public product lines.