The
User's Manual might be of more help here (but I checked, it isn't much more information).
I think for parallel decoding, you basically have to specify a 1-to-1 relationship between a bit (which is a HIGH or LOW signal on a single pin) and a channel.
So if you have a parallel channel with a 1 byte word (e.g. 8 bits) then you would need to map bits like so:
Pin 1 - Bit 0 - LA Channel 0
Pin 2 - Bit 1 - LA Channel 1
...
Pin 8 - Bit 7 - LA Channel 7
Then, the scope could decode those 8 pins into one byte, and display that data.