• CELL
  • Intermediate
  • 5 min
  • Serial CLI

Recipe · Intermediate · CELL

How to send an SMS

Use CELL mode sms operations to send a message from a GSM/LTE modem after SIM and network checks.

Cellular modem with SIM card and radio signal.
Start with read-only checks, then move to write, replay or automation only when the setup is understood.
Step 1

Commands

Use the shortest command path that matches the documented firmware workflow. When a mode needs setup, follow the prompts shown on first entry.

Result

What it means

The command path is working when the target responds and the firmware prints the expected menu, status or captured data.

Troubleshooting

  • Re-enter the mode setup when pins or peripherals are not already initialized.
  • Check common ground and target voltage before blaming software.
  • Prefer Serial CLI for long captures or high-volume output.
  • Repeat the read or capture to confirm stability.

Next steps

  • Save the output in your project notes.
  • Compare the result with the full wiki page for mode-specific details.
  • Create a shorter alias if you repeat this workflow often.

cellular SMS sending FAQ

What should pass before I send an SMS?

Confirm modem response, SIM status and network registration first. SMS failures are much easier to debug after the AT link and operator registration are known good.

Why can SMS sending fail after registration?

The plan may not allow SMS, the message center may be misconfigured, the number format may be wrong, or the operator may reject the request.

Can this command create operator charges?

Yes. SMS operations can bill the SIM plan. Use your own SIM, keep test messages minimal, and avoid sending to numbers you do not control.

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