Flight Computer

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Flight Computer

Data Logging

The flight computer is logging data to an SD card from the various sources that are hooked up to it. Most notably the ADC and the GPS.

There is a parser available that will parse the data from both CONNERY-1 and CONNERY-2, it is called ParseFCU. It is known to compile on Linux, Mac OS X and FreeBSD. It will parse the raw data images and provide the user with a comma separated values file that can then easily be imported into Excel or any other software that imports CSV files for parsing/graphing.

CONNERY-1

Version: 1

<4 bytes>
    - Last known good write

!
    - Start byte

<2 bytes> x 8
    - ADC channels

<1 byte>
    - Extra write of the last byte of the last ADC channel. Ignore.

($...)?
    - GPS string

\n\r
    - New line/return. Ignore these.

#
    - Stop byte

The string is still entirely valid even if GPS data is not available. Please be aware of this when parsing the raw data.

CONNERY-2

Version: 2

<4 bytes>
    - Last known good write

!<0x82>
    - Start bytes

<2 bytes> x 8
    - ADC channels

<1 byte>
    - Extra write of the last byte of the last ADC channel. Ignore.

($...)?
    - GPS strings, may contain new lines, ignore those (GPGGA, and PGRMV)

\n\r
    - New line/return. Ignore these.

#<0x83>
    - Stop bytes

The GPS strings do not have to be in the string for it to be a valid string. Please be aware of this when parsing the raw data.

CONNERY-x

For the next version, a change has been requested, instead of having the parsing program guess what version of the file we are working with, after the 4 bytes for the last known good write a new byte that specifies what version of the file we are parsing. This is purely for the ease of parsing new data structures.

Version: x

<4 bytes>
    - Last known good write

<1 byte>
    - Log file version number

!<0x82>
    - Start bytes

<2 bytes> x 8
    - ADC channels

<1 byte>
    - Extra write of the last byte of the last ADC channel. Ignore.

($...)?
    - GPS strings, may contain new lines, ignore those (GPGGA, and PGRMV)

\n\r
    - New line/return. Ignore these.

#<0x83>
    - Stop bytes

The GPS strings do not have to be in the string for it to be a valid string. Please be aware of this when parsing the raw data.

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