Overview

The CELL parameter group configures the 4G/LTE Cellular Telemetry subsystem. This allows the autopilot to communicate over cellular networks using supported modems (e.g., Skywire, SIMCOM) connected via Serial or USB (PPP).

Note: The parameter CELL_COUNT listed in some databases often belongs to the OSD library (used for displaying average cell voltage) rather than the Cellular driver itself. This overlap can be confusing.

Key Concepts

1. Cellular Modems

ArduPilot can manage basic modem initialization (AT commands) to establish an IP connection. Once connected, telemetry is routed over UDP/TCP to a Ground Station IP.

2. OSD Helper (CELL_COUNT)

(If present) This parameter helps the OSD calculate the "Average Cell Voltage" by dividing the total pack voltage by the number of cells.

• Auto (-1): Guesses the cell count based on total voltage at boot (assuming 3.7V-4.2V/cell).
• Manual: Forces a specific count (e.g., 6S, 12S). Useful if you plug in a partially discharged pack that might be mistaken for a full pack of lower cell count.

Parameter Breakdown

• CELL_ENABLE: Master switch for cellular driver.
• CELL_TYPE: Driver selection.
• CELL_PIN: PIN code for the SIM card.
• CELL_APN: Access Point Name string.

(Note: CELL_COUNT is functionally part of the OSD group logic).

Integration Guide

1. Hardware: Connect modem to a UART.
2. Serial: Set SERIALx_PROTOCOL = 1 (MAVLink) or specific modem protocol.
3. Config: Set CELL_ENABLE, CELL_TYPE, and CELL_APN.

Developer Notes

• Library: libraries/AP_Cellular (Driver) and libraries/AP_OSD (Display).