2 == Flight Data Recording
4 Each flight computer logs data at 100 samples per second
5 during ascent and 10 samples per second during descent, except
6 for TeleMini v1.0, which records ascent at 10 samples per
7 second and descent at 1 sample per second. Data are logged to
8 an on-board flash memory part, which can be partitioned into
9 several equal-sized blocks, one for each flight.
11 .Data Storage on Altus Metrum altimeters
12 [options="header",cols="1,1,1,1"]
14 |Device |Bytes per Sample |Total Storage |Minutes at Full Rate
15 |TeleMetrum v1.0 |8 |1MB |20
16 |TeleMetrum v1.1 v1.2 |8 |2MB |40
17 |TeleMetrum v2.0 |16 |8MB |80
18 |TeleMini v1.0 |2 |5kB |4
19 |TeleMini v2.0 |16 |1MB |10
20 |EasyMini |16 |1MB |10
21 |TeleMega |32 |8MB |40
22 |EasyMega |32 |8MB |40
25 The on-board flash is partitioned into separate flight logs,
26 each of a fixed maximum size. Increase the maximum size of
27 each log and you reduce the number of flights that can be
28 stored. Decrease the size and you can store more flights.
30 Configuration data is also stored in the flash memory on
31 TeleMetrum v1.x, TeleMini and EasyMini. This consumes 64kB
32 of flash space. This configuration space is not available
33 for storing flight log data. TeleMetrum v2.0, TeleMega and EasyMega
34 store configuration data in a bit of eeprom available within
35 the processor chip, leaving that space available in flash for
38 To compute the amount of space needed for a single flight, you
39 can multiply the expected ascent time (in seconds) by 100
40 times bytes-per-sample, multiply the expected descent time (in
41 seconds) by 10 times the bytes per sample and add the two
42 together. That will slightly under-estimate the storage (in
43 bytes) needed for the flight. For instance, a TeleMetrum v2.0 flight spending
44 20 seconds in ascent and 150 seconds in descent will take
45 about (20 * 1600) + (150 * 160) = 56000 bytes of storage. You
46 could store dozens of these flights in the on-board flash.
48 The default size allows for several flights on each flight
49 computer, except for TeleMini v1.0, which only holds data for a
50 single flight. You can adjust the size.
52 Altus Metrum flight computers will not overwrite existing
53 flight data, so be sure to download flight data and erase it
54 from the flight computer before it fills up. The flight
55 computer will still successfully control the flight even if it
56 cannot log data, so the only thing you will lose is the data.