Hi Hartmut (und Jörg und Sigi)
The answer is exactly the same as the one concerning the CAT interface : the transceiver IS the software, and the software IS the transceiver. Just consider the Anan or any rig of this kind of architecture as a simple hardware "extension" of your software.
To be more precise, if you need to use digital modes (fldigi, FreeDV, FT8 etc), you'll just have to install the software on your computer if not allready done, and "connect" the audio output of the software with the "audio input" of the main SDR software (powerSDR for example, but it's not the only one).
This connection is made with another kind of software called a "virtual cable". VB-Audio https://www.vb-audio.com/
Voicemeeter, Virtual Audio Cable, Banana... some are free, others are sold (but these are not expensive apps)
In other words, you'll never use a real cable anymore, and the jack output on your computer are absolutely useless.
You'll certainly be lost during the first hour or two when dealing with the digital modulation software output and the digital input of the SDR software (and the audio output of the SDR software going to the audio input of the digital demodulation software)... it's exactly as messy and confusing than plugging wires on a Hifi amplifier :-/ .
But after "virtually cabling" your first software, you'll see that it's really obvious and simple.
just to give you an idea, have a look on my blog post https://f6itu.wordpress.com/2017/04/23/ ... ee-as-ber/
you don't have to care to what's written in French.... just have a look at the screen captures. VB Audio acts as a windows driver and do the "pipe" between all applications, sources of sinks, in any direction you need .
If you are using Linux, it's almost as simple with PulseAudio :same logic.