How to Start Developing Firmware Remotely

Modern embedded development starts with modern practices. Remote work has revolutionized the way that engineering is done, and it is now more possible than ever for traditionally on-site work to be done remotely. In this post we’ll discuss the technologies that we use to make remote embedded development possible.

Remote Development Model

In this post we will be assuming the following model of communication:

Engineer ↔ Remote Machine ↔ TailScale VPN Connection ↔ “On-Site” Machine ↔ Debug and Measurement Tools ↔ Hardware under Test

Another term for this is Hardware-in-the-Loop or HIL. This setup allows us to remotely test and control the hardware from anywhere in the world with an internet connection.

Designing Hardware With Remote Development In Mind

Your hardware setup should be designed to operate completely autonomously, without requiring any manual intervention or physical access once configured. This approach ensures that all development, testing, and debugging activities can be performed entirely through remote interfaces. This means:

• All debugging probes should be able to remain connected, with no need to plug or unplug cables.
• Physical button interactions should be able to be mocked with software-triggered events.
• It must be possible to power cycle both the “on-site” machine device and hardware under test without a loss of connectivity.

Remotely Controllable Hardware Measurement Tools

These tools should adhere to the same fundamental principles with no need for physical cable management or connection changes during testing. When selecting measurement tools, having more channels and I/O options than you may think you need provides greater flexibility and future-proofing for your testing setup. The goal is to establish comprehensive test coverage by having the ability to probe and monitor every conceivable test point that could potentially be impacted by firmware modifications or updates. This approach ensures that remote debugging and testing can be conducted thoroughly without requiring physical access to the hardware.

Here are some of our tried and true favorite tools:

• Digilent Analog Discovery Series
• In particular we recommend the Digilent Analog Discovery 3.
• Segger JLink
• Segger offers J-Link Remote Server for connecting to the probe over a network connection.
• PCBite Probes
• These probes can easily be held in place where a standard probe would need to be hand held. They are particularly useful for probing small test point vias on PCBs.

Using TailScale For Connectivity Anywhere

TailScale provides a powerful VPN solution that enables seamless connectivity between your devices, offering both personal and organization-wide options with a generous free tier supporting up to one hundred devices. This secure networking tool creates an encrypted tunnel between your machines, making remote development feel like local work. To establish the connection between your “on-site” and remote machines, you’ll need to configure both devices within your TailScale network, which can be done through a straightforward setup process. Once configured, TailScale maintains persistent connections and automatically handles network traversal, ensuring reliable remote access regardless of your location or network environment.

You can get started with TailScale by following the official setup guide here.

Using Remote Desktop Software to Control Hardware

We favor command line tools such as SSH and SFTP over graphical tools whenever possible. SSH and SFTP work with every operating system and are the basis for many connectivity solutions. Many programs such as VSCode have built-in functionality or extensions that allow you to connect to a remote machine. That being said, inevitably there are programs that require a graphical interface in order to function properly.

In these cases we favor the following platform-specific solutions for remote access:

• Linux
• VLC Viewer/Server
• Mac
• ScreenShare
• Windows
• RDC/RDP

Do Embedded Firmware Right with Dojo Five on Your Team

If you ‘re looking for a knowledgeable team of engineers on to work on your next embedded project, book a call with us to get the conversation started.