DSD+ uses command line switches meaning you give DSD+ all the commands you want when you start it - once DSD+ is running it only responds to 3 keystrokes, basically. The options for DSD+ are "set" from the command line when it's started up, not while it's running. Once it's operational it will respond to pressing the following keys as noted in the read_me/user guide:
Code:
- Toggle command line options display
I Toggle input audio level display
R Start/stop recording of raw input audio to .wav file
S Display group/user stats
Esc Terminate real time decoding
Ctrl-C Terminate .wav file decoding
All of the other potential options must be included on the command line (or added to the shortcut command if you create one). Say for example you want DSD+ to listen for and decode only the P25 traffic ignoring everything else (this makes it work more efficiently, actually), you'd start the program with the following command (replace dsd.exe with whatever you have the program named, of course, as some people do rename the executable):
dsd.exe -f1
dsd.exe is the program itself, and the command line switch -f1 tells it to ignore everything except P25 traffic. Another example might be:
dsd.exe -f1 -v4
which does the same thing but also tells DSD+ to display as much logging info as possible (be as verbose as possible when displaying info) so you'll see talkgroup info, etc.
There are other threads discussing a lot of the command line switches, but they're all listed in the "user guide" text file that's included with the DSD+ archive.
Hope this helps...