Protocol Definition between Ground Stations and Command RX
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Introduction
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using DTMF on FM
receiver should be activated for min. 200ms every 5s to listen for new commands
signs get scrambled using a secret Code Table
every command must be aknowledge by a beacon with the unscrambled code

Frame
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#42<code><cs>

Checksum:
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Xor over Signs intrepreted as HEX (0-9A-D#*)

Codes:
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0    ..    shut up (rfkill)
1    ..    unshut up (no rfkill)

8    ..    activate payload reciever

C    ..    cancel all commands
#    ..    reset
*    ..    safe mode