• GPIO
  • Beginner
  • 5 min
  • Serial CLI

Recipe · Beginner · GPIO

How to display a GPIO logic trace

Use the global logic command to display a small logic analyzer view directly on the ESP32 screen.

Waveform capture with signal traces.
The built-in screen can show a quick logic trace for one GPIO.

Wiring View

BP signalGPIOGNDBP GND
Generated from the wiring summary: to BP.
Step 1

Commands

These commands are documented as global or quick-start commands.

Result

What it means

If the command returns the expected output, the firmware and terminal session are ready for the next workflow.

Troubleshooting

  • If the screen stays flat, trigger activity on the target.
  • Use the SUMP logic analyzer recipe for deeper capture.
  • Check the selected GPIO number.

Next steps

  • Try the same workflow on a known safe pin or target.
  • Save the useful command as a note or alias.
  • Move to the protocol-specific recipe once the basics work.

On-device logic trace FAQ

When is the on-device logic view enough?

Use it for a quick visual check that one GPIO is changing while you are at the bench. It is ideal before deciding whether a deeper capture is worth setting up.

What does the on-device logic view optimize for?

It optimizes for quick visual checks directly on supported hardware. Use it to spot activity or idle lines before moving to longer host-side captures.

When should I use the SUMP logic analyzer instead?

Use the SUMP logic analyzer when you need multiple channels, larger captures, timing inspection in PulseView, or evidence that can be saved and shared.

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