• UART
  • Beginner
  • 5 min
  • Serial CLI

Recipe · Beginner · UART

How to send repeated UART text with spam

Use UART spam to send a repeated text or newline pattern at a fixed interval while testing serial devices.

UART signal lines between two connected devices.
A practical ESP32 Bit Pirate recipe based on documented firmware commands.
Step 1

Commands

Run this sequence from the CLI. Adjust pins, addresses or filenames to match your own setup.

Result

What it means

Spam is useful for timing-sensitive prompts, bootloader windows and serial peripherals that need periodic input.

Troubleshooting

  • Re-enter the selected mode setup if pins changed.
  • Confirm the target shares ground with the ESP32 Bit Pirate.
  • Start with short commands before using longer capture or bridge sessions.

Next steps

  • Use read or raw to watch replies.
  • Create an alias for the repeated probe.
  • Use trigger when replies should be pattern-based.

UART spam pattern FAQ

When is UART spam useful?

It is useful when a target only answers during a short boot window, after repeated newlines, or after periodic AT-style probes. Start with slow intervals before using aggressive timing.

Can spam damage a target?

Repeated serial text is usually low risk electrically, but it can trigger commands, fill logs or interrupt bootloaders. Use harmless patterns first and test only devices you control.

When is UART spam useful compared with a single write?

Spam is useful when a target only samples input during short windows or when you want repeated prompts during boot. A single write is cleaner once you know the timing.

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