NSEU,on the ones that I fly, once the Engine mode selector is switched to START, the FADEC powers up and the PACK valves are closed. The Pack valves are opened 30 secs after the second engine start . I don't know if this logic is engine specific or common across the 320 fleet.
We have more control over the start
This is the part which baffles me. When you do a MAN start , apart from the dual igniters firing as rightly pointed out by Meikleour in one of the replies, I find no difference in the start procedure as listed in the procedure . The procedure says , place the master switch to ON position, when the N2 reaches 22% which is what the FADEC actually does in an automatic start . So in effect you are just mimicking the actions a FADEC would do. If not, can you please throw light on the other cues that help you in timing the start sequence better than what a FADEC would do ?