Grab a scope and unleash your inner engineer!

Developing embedded systems is an exciting, complex, and sometimes maddening journey. Recently, we’ve highlighted how LLMs can quickly generate example codes for STM32 devices, creating initialization functions, base classes, and toy examples to help you get started. But here’s the million-dollar question: Will it work in the real world?

In a real product, success isn’t just about code compiling or peripherals initializing. It’s about ensuring that timings are precise, interrupts are caught and handled correctly, and everything runs smoothly without blocking or missing functionality. Let me paint a familiar scenario:

Imagine you’re building a device that plays MP3 audio over SPI, reads data from an SD card via SDMMC, and displays content on an LCD. One microcontroller, one core—juggling all these tasks. At first, you test each feature individually. The audio plays beautifully. The LCD looks perfect. The SD card reads and writes flawlessly. Great, right?

But then you combine everything, and chaos ensues. The audio starts skipping samples, riddled with clicks and pauses. The SD card randomly fails, freezing functionality. The LCD screen stops updating. And now, you’re deep in the weeds of debugging.

This is where the honeymoon phase with LLMs ends. While LLMs can generate functional code snippets, they won’t magically fix real-world integration problems. At this point, relying on LLM recommendations often feels like running in circles—it suggests solutions you’ve already tried a dozen times.

The only way forward? Back to the lab. Armed with an oscilloscope or logic analyzer, you dig into the signals, timings, and interactions. You discover that SPI is too slow to keep up with audio sampling, and the timer triggering the SPI transfer is misconfigured. You patch the firmware, but new problems crop up—SDMMC interrupts are causing conflicts, so you switch to DMA to keep things running smoothly.

This process can take days, even weeks. It’s a grind. But it’s also why experienced embedded engineers are indispensable. They understand that debugging isn’t just about fixing code—it’s about peeling back layers of complexity to uncover the root cause of failures.

The takeaway? LLMs are fantastic for accelerating the early stages of development. They help you write boilerplate code, experiment, and prototype faster. But when it comes to fine-tuning, integration, and real-world reliability, nothing beats the expertise of a seasoned engineer with a scope in hand and the patience to see it through.