Modulator channels will automatically be enabled if you redirect data 
from a demodulator to it. 
E.g._:

first demod on bridge 0 TAB1, modulator on bridge 1.

echo "00 10" > /sys/class/ddbridge/ddbridge0/redirect

Currently it is fixed to QAM256. Controls will be added later.
Rate control is experimental and PCR correction also not
implemented yet. So, depending on the reception device
there can be disturbances in playback.

It is now also possible to chain redirects.
E.g., demod and modulator as above, CI on bridge 0 TAB 2:

echo "00 01" > /sys/class/ddbridge/ddbridge0/redirect
echo "02 10" > /sys/class/ddbridge/ddbridge0/redirect

The stream is also still available at the demux device 
belonging to the demod devices.

Now write and start an application (not provided) that 
talks to the CI to decrypt the desired services.
For testing one can use a standard application that
supports decryption. Additionally to seeing the
decoded service on the PC it will then also be streamed
into cable by the modulator.