To debug a firmware issue, I would start by isolating the problem through systematic testing and logging. I would use tools like JTAG or a serial debugger to step through the code and inspect register values. Additionally, I would check for common issues such as memory leaks, stack overflows, or incorrect peripheral configurations. By analyzing the logs and using breakpoints, I can pinpoint the exact location of the issue and implement a fix. Finally, I would thoroughly test the system to ensure the problem is resolved and no new issues have been introduced