LEA-M8S / LEA-M8T - Hardware Integration Manual
UBX-13003140 - R07
Production Information
Design
Page 14 of 31
The current active antenna status can be determined by polling the UBX-MON-HW monitor command. If an
antenna is connected, the initial state after power-up is “Active Antenna OK.”
No
Super-
vision
Active
Antenna
OK
Open
Circuit
detected
Short
Circuit
detected
Powerup
Events AADET0_N
User controlled events
Disable Supervision
Enable Supervision
Short Circuit
detected
Disable
Supervision
Antenna
connected
Short Circuit
detected
open circuit
detected, given
OCD enabled
Periodic
reconnection
attempts
Figure 11: State diagram of active antenna supervisor
The module firmware supports an active antenna supervisor circuit, which is connected to the
AADET_N
pin. For
an example of an open circuit detection circuit, see Figure 14. High on
AADET_N
means that an external
antenna is not connected.
Status reporting
At startup, and on every change of the antenna supervisor configuration, the LEA-M8S and LEA-M8T modules
will output an NMEA
($GPTXT
) or UBX (
INF-NOTICE
) message with the internal status of the antenna supervisor
(disabled, short detection only, enabled).
Abbreviation
Description
AC
Antenna Control (e.g. the antenna will be switched on/ off controlled by the GNSS receiver)
SD
Short Circuit Detection Enabled
SR
Short Circuit Recovery Enabled
OD
Open Circuit Detection Enabled
PdoS
Power Down on short
Table 3: Active Antenna Supervisor Message on startup (UBX binary protocol)
To activate the antenna supervisor use the UBX-CFG-ANT message. For further information, refer to the
u-blox M8 Receiver Description Including Protocol Specification
Similar to the antenna supervisor configuration, the status of the antenna supervisor will be reported in an
NMEA (
$GPTXT
) or UBX (
INF-NOTICE
) message at start-up and on every change.
