To Lee Phillips
For Digitrax you need a DT400 or 402 throttle. Plug it in to the loconet. Power on the system. Put the loco on the track. Press the PRGM button and look at the throttle display window.
For main track programming, it should show Po. If you’re using a programming track the choices are PH, Pd, Pg. To change between these keep pressing the PRGM button. Some decoders respond better to one over another.
To choose which CV turn the left knob. To set the value turn the right knob.
Hope this gets you started.