To see more details in the graphs, sampling rate was changed to 1 sample / second, and values offset and scaled (except Volts):
Power 'jumps around between 2.75..3.05 Volts. The longer the switched-off phase is, the slower satellites show. After a short - but still several minutes - break, many satellites are found quickly (5..6). Current was measured with a simple digital multi-meter at an average of 30 mA...
On a 'really cold' start it took a while to get to level of fix = 1 even though some satellites were already found; and it takes quite a while to get to level of fix = 2, even though about the same number of satellites were detected much earlier. I did not look yet after what time the long and lat values become stable and useful. It could be worth-while to look into more recent generations of GPS modules that are much faster - not only in the interval of delivering sentences but also in start-up. A NEO 7M is still waiting on my desk to be 'broken in'. 7M does not only find 20..30% more satellites and quicker, it is more accurate, and has also an extended supply voltage range: Vcc 1.65..3.6V (vs 2.7..3.6V of 6M). The extended supply voltage may require to sacrifice less GPIO pins for just power supply. ;). How much current (mA) an STM32 pins can source is specified based on the voltage drop from Vcc...
Note: The lower number of satellites found in this session compared to earlier session - 7..8 vs 9..12 - was due to a less optimal position of the GPS towards the open sky...
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