ardupilot/libraries/AP_Logger
Peter Barker a17a8faf42 AP_Logger: move GSF logging from EKF files into GSF files 2021-02-23 12:36:33 +11:00
..
examples AP_Logger: make block logger conform to mavlink expectations of numbering 2020-09-05 10:20:39 +10:00
AP_Logger.cpp AP_Logger: Add missing const in member functions 2021-02-03 18:45:14 +11:00
AP_Logger.h AP_Logger: move gps logging structures into AP_GPS 2021-02-17 11:30:01 +11:00
AP_Logger_Backend.cpp AP_Logger: Add missing const in member functions 2021-02-03 18:45:14 +11:00
AP_Logger_Backend.h AP_Logger: Add missing const in member functions 2021-02-03 18:45:14 +11:00
AP_Logger_Block.cpp AP_Logger: Add missing const in member functions 2021-02-03 18:45:14 +11:00
AP_Logger_Block.h AP_Logger: Add missing const in member functions 2021-02-03 18:45:14 +11:00
AP_Logger_DataFlash.cpp AP_Logger: allow each backend to be compiled out 2021-01-08 12:48:55 +11:00
AP_Logger_DataFlash.h AP_Logger: allow each backend to be compiled out 2021-01-08 12:48:55 +11:00
AP_Logger_File.cpp AP_Logger: allow each backend to be compiled out 2021-01-08 12:48:55 +11:00
AP_Logger_File.h AP_Logger: allow each backend to be compiled out 2021-01-08 12:48:55 +11:00
AP_Logger_MAVLink.cpp AP_Logger: Add missing const in member functions 2021-02-03 18:45:14 +11:00
AP_Logger_MAVLink.h AP_Logger: Add missing const in member functions 2021-02-03 18:45:14 +11:00
AP_Logger_MAVLinkLogTransfer.cpp AP_Logger: Add missing const in member functions 2021-02-03 18:45:14 +11:00
AP_Logger_SITL.cpp AP_Logger: allow each backend to be compiled out 2021-01-08 12:48:55 +11:00
AP_Logger_SITL.h AP_Logger: allow each backend to be compiled out 2021-01-08 12:48:55 +11:00
LogFile.cpp AP_Logger: move gps logging structures into AP_GPS 2021-02-17 11:30:01 +11:00
LogStructure.h AP_Logger: move GSF logging from EKF files into GSF files 2021-02-23 12:36:33 +11:00
LoggerMessageWriter.cpp AP_Logger: support new replay system 2020-11-10 16:15:45 +11:00
LoggerMessageWriter.h AP_Logger: Add missing const in member functions 2021-02-03 18:45:14 +11:00
README.md AP_Logger: README add multiplier descriptions 2021-01-04 20:45:38 +11:00

README.md

Logger Notes

Format Types

The format type specifies the amount of storage required for the entry and how the content should be interpreted.

Char C Type
a int16_t[32]
b int8_t
B uint8_t
h int16_t
H uint16_t
i int32_t
I uint32_t
f float
d double
n char[4]
N char[16]
Z char[64]
L int32_t latitude/longitude (so -35.1332423 becomes -351332423)
M uint8_t flight mode
q int64_t
Q uint64_t

Legacy field types - do not use. These have been replaced by using the base C type and an appropriate multiplier column entry.

Char CType+Mult
c int16_t * 100
C uint16_t * 100
e int32_t * 100
E uint32_t * 100

Units

All units here should be base units. This means battery capacity uses "amp * second" not "milliAmp * hours". Please keep the names consistent with Tools/autotest/param_metadata/param.py:33

Char Unit Abbrev. Description Notes
'-' "" no units e.g. Pi or a string
'?' "UNKNOWN" Units which haven't been worked out yet....
'A' "A" Ampere
'd' "deg" of the angular variety -180 to 180
'b' "B" bytes
'k' "deg/s" degrees per second Not an SI unit, but in some situations more user-friendly than radians per second
'D' "deglatitude" degrees of latitude
'e' "deg/s/s" degrees per second per second Not an SI unit, but in some situations more user-friendly than radians per second^2
'E' "rad/s" radians per second
'G' "Gauss" Gauss Not an SI unit, but 1 tesla = 10000 gauss so a simple replacement is not possible here
'h' "degheading" 0.? to 359.?
'i' "A.s" Ampere second
'J' "W.s" Joule (Watt second)
'l' "l" litres
'L' "rad/s/s" radians per second per second
'm' "m" metres
'n' "m/s" metres per second
'N' "N" Newton
'o' "m/s/s" metres per second per second
'O' "degC" degrees Celsius Not an SI unit, but Kelvin is too cumbersome for most users
'%' "%" percent
'S' "satellites" number of satellites
's' "s" seconds
'q' "rpm" revolutions per minute Not an SI unit, but sometimes more intuitive than Hertz
'r' "rad" radians
'U' "deglongitude" degrees of longitude
'u' "ppm" pulses per minute
'v' "V" Volt
'P' "Pa" Pascal
'w' "Ohm" Ohm
'Y' "us" pulse width modulation in microseconds
'z' "Hz" Hertz
'#' "instance" (e.g.)Sensor instance number

Multipliers

This multiplier information applies to the raw value present in the log. Any adjustment implied by the format field (e.g. the "centi" in "centidegrees" is IGNORED for the purposes of scaling. Essentially "format" simply tells you the C-type, and format-type h (int16_t) is equivalent to format-type c (int16_t*100) tl;dr a GCS shouldn't/mustn't infer any scaling from the unit name

Char Multiplier Description
'-' 0 no multiplier e.g. char[4]
'?' 1 multipliers which haven't been worked out yet
'2' 1e2
'1' 1e1
'0' 1e0 x1
'A' 1e-1
'B' 1e-2
'C' 1e-3
'D' 1e-4
'E' 1e-5
'F' 1e-6
'G' 1e-7
'!' 3.6 (milliampere * hour => ampere * second) and (km/h => m/s)
'/' 3600 (ampere * hour => ampere * second)