I got yesterday my APM with a MediaTek GPS. I've been figuring out how to read the log files. I had some success and was able to make and read a log of a walk around my block:
This looks in principle fine, but the data seems to have time leaps (e.g. height)
I also find in the serial data several duplicated packages (same time, same data). If I filter all 0-locks and the duplicated data entries and then plot the data against their index (instead of time), I get a more or less continuous curve:
Has anyone experienced this? Is the time delivered by the GPS module reliable? Are there any other sources for time?