Experiment 11: Debugging Interrupt Signals

Objective: Learn how to monitor and debug interrupt signals in a microcontroller or embedded system to understand their behavior and timing.

Steps:

1. Connect the Analyzer to the Interrupt Pin:
   • Identify the interrupt signal line on the microcontroller or embedded system. This is typically a GPIO (General Purpose Input/Output) pin configured for interrupt input.
   • Connect the logic analyzer to the interrupt pin. Ensure the voltage levels are compatible with the analyzer (e.g., 3.3V or 5V).
   • If available, connect the ground of the analyzer to the system’s ground to ensure proper signal reference.
2. Trigger an Interrupt in the System:
   • Generate an interrupt event in the system. This could be from a button press, a timer, a sensor trigger, or a software interrupt.
   • Ensure that the interrupt service routine (ISR) is correctly set up in the system, and it is being triggered by the interrupt event.
   • Monitor the analyzer’s waveform to capture the interrupt signal when the event occurs.
3. Analyze Timing and Behavior of the Interrupt Signal:
   • Observe the interrupt signal on the analyzer’s display. The signal should typically show a rising or falling edge when the interrupt occurs.
   • Measure the timing of the interrupt signal, including the duration of the interrupt pulse and any delays between trigger events.
   • If necessary, use the logic analyzer's triggering features to capture and isolate the exact moments when interrupts are triggered and processed.
   • Analyze the interrupt signal’s behavior, such as the ISR response time and any possible glitches or missed interrupts, to ensure the system is functioning as expected.

Expected Outcome:

Through this experiment, you will gain insight into how interrupts are triggered and processed in embedded systems. You will also develop skills in using a logic analyzer to debug and verify interrupt behavior, timing, and system responses to real-time events.