Yamaha DTXpress/DTXplorer/DTXtreme

Hi everyone, I have checked the archive and couldn't find similar
posts- hope I didn't miss 'em.

Anyway, I have recently purchased a DTXpress III (Standard) and wish
to connect it, via midi, to a sampler. This is not a problem and poses
no issues.

What I am interested in is triggering different samples using the same
pad/cymbal. Not at the same time but in some kind of progression.
Basicall if I have 3 samples and hit the pad once it would trigger
sample #1, hitting it again would trigger sample #2, once more
triggering sample #3.

Does anyone know of a way of doing this - I am wondering whether it
would be something similar to the 'Pad Song' Function where it only
plays bars of a song, if these bars can have midi notes assigned then
this should do the trick but I'm not sure

Hope this makes sense and that I haven't bored you to death

Thanks.

Tris