989 ??????'s

well i have had a 989 for about a week now and love it but have a few ???'s


when i charge batts and there fully charged, just topping them off, it will charge them to a point and then say there done, idk if its right because i got some gp 3300 and it will say theres 600 mah and then go into trickle, is that saying it put that much mah into the pack, or thats what its at??

i havent ran the packs so i thinkn they need to be discharged then charged, it works for my other batts, im just wondering what happens when i want to top a pack off