u-blox C94-M8P Series User Manual page 24

Enable the AT command mode by sending sequence "+++" (quickly type "+++" and wait for 1 second) via the
serial link. The radio module sends "OK" to indicate entering the AT command mode.
Figure 17: Radio module sends "OK" prompt through serial link when AT Command Mode is Enabled
In AT command mode, the radio module accepts AT commands and gives response correspondingly. In case of
wrong AT commands, the radio module returns ERROR as the response.
Figure 18: Send AT commands to Radio Module
Table 5 shows the AT command set that is supported by the C94-M8P application board.
Table 6 shows all radio parameters that are configurable. For more information about configuring the radio
module used by C94-M8P, see http://copter.ardupilot.com/wiki/common-3dr-radio-advanced-configuration-
and-technical-information/.
UHF operation needs to be on licensed bands according to regions.
Remember to enable GNSS module UART output on Base when finished with radio communication link
configuration.
UBX-15031066 - R06 Advance Information
C94-M8P - User Guide
Appendix
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