GPRS decode tutorial

[Sylvain Munaut]

> mo1:
>  ./host/osmocon/osmocon -m c123xor -p /dev/ttyUSB0
> ./target/firmware/board/compal_e88/layer1.compalram.bin
> mo2:
>  ./host/osmocon/osmocon -m c123xor -p /dev/ttyUSB1
> ./target/firmware/board/compal_e88/layer1.compalram.bin
>
> If if use only one mobile, ttyUSB0 / ttyUSB1 is working,
> but if I started both at the same time, only one mobile is working.
> Same with 2 different firmwares.
>
> How can I set up more phones to get the whole frame / up- and downlink.

1) You must launch everything twice, including launching ccch_scan (or
layer23 for older version).
2) Look in the command line option of osmocon and ccch_scan, you will
find an option to specify the l2 socket. Each pair of software needs a
different socket.
3) There is a software in the gprs git to then 'combine' both output
in a single file