pocsag-encoder

Encode pocsag messages to dump to a file. This project is designed to make it easier to understand how pocsag works, with a heavily-commented implementation.

Takes input as a series of lines, one line per message.

Message format is as follows:

address:message

where address is an integer, and message is contents to be encoded.

Adds a random delay to the output feed of 1 to 10 seconds by default. This is configurable in pocsag.c near the bottom of the file by the MIN_DELAY and MAX_DELAY defines.

pocsag reads from stdin and writes signed 16 bit little-endian samples to stdout.

Example Usage

# encode two messages, and verify multimon can decode them
printf '1:hello\n9:world' | pocsag | multimon-ng -c -a POCSAG512 -q -

# encode a message to a file (raw, 22050Hz PCM S16LE)
printf '11:good evening' > transmission.raw

Compilation

pocsag doesn't rely on any dependencies but the C standard libraries. Use make to compile, or run your own C compiler manually. Feel free to sudo make install if you want.

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DAPNET integration

This section is about connecting the transmitter to send messages coming form the dapnet network.

Dependencies

to make this work, you will need:

1. python and RPi.GPIO package
2. ffmpeg
3. mpv

Test run

edit the global variables CALLSIGN and PASSWORD according to your DAPNET transmitter credentials and run python dapnet_messages.py

RIC filtering

Soon(tm)