We are using a GX5_25 with an external GPS with an external PPS input. I experimented with this a bit through my own mscl driver https://bitbucket.org/croman_and_the_barbarians/mscl_ros/src/master/ . The only way I have found to check if the external pps input is working was to look at the gps_correlation_timestamp message.
The gps_correlation_timestamp was already listed under ahrsChannels so I added a corresponding message, IMU message switch case and publisher.
The published message, GpsCorrelationTimestampStamped, has an attached ROS header so that it can be easily synchronized with the other imu related messages (IMU/MAG). If recorded, it also allows you to check in post that the GPS time was properly converted to UTC (ROS time).
We are using a GX5_25 with an external GPS with an external PPS input. I experimented with this a bit through my own mscl driver https://bitbucket.org/croman_and_the_barbarians/mscl_ros/src/master/ . The only way I have found to check if the external pps input is working was to look at the gps_correlation_timestamp message.
The gps_correlation_timestamp was already listed under ahrsChannels so I added a corresponding message, IMU message switch case and publisher.
The published message, GpsCorrelationTimestampStamped, has an attached ROS header so that it can be easily synchronized with the other imu related messages (IMU/MAG). If recorded, it also allows you to check in post that the GPS time was properly converted to UTC (ROS time).