Guys, I'm flying a blimp indoors and connected APM2.0 to the receiver via Y cables to log radio inputs and sensor outputs. When I look at the log files in dataflash I can see that during the flight all GPS related data are zero since there is no GPS indoors as expected. However 'GPS time' value is zero for some time then it starts to increase. If there is no GPS how can this happen? First I assumed maybe it only can see one satellite so it can get the time but not the remaining parameters, however when I look at 'GPS sats' parameter which logs the number of locked satellites on log file, it is always zero. Also I have another concern regarding waypoint navigation. Without GPS can I assign waypoints on a custom made map?