EXS 24 Logic Sampler Users Group

Using Logic Pro 6.4.1 and EXSmkII, is there a way to assign a sample 
to a root key that will automatically loop the sample over and over 
after a single key(note) push? My very limited experience has found 
that in order for a loop to play, I have to hold the key down or 
repeatedly push the key in time with a beat. I would like the loop to 
repeat after one push and then use the other keys(samples) to play 
over that loop. This is probably a real simple yes or no, but I 
assure you I have thoroughly read the EXSII manual that came with 
Logic Pro and have not found this feature covered. 

Thanks