The FADEC (Full Authority Digital Engine Control) is your engine's big boss. On the A320, there are 2 FADECs (one per eng).
During auto starts, the FADEC controls the start valves, the igniters, HP & LP fuel valves, FF, etc. The FADEC also calculates N1 rated limits & provides engine protection.
As its source of power during the flight, the FADEC uses individual, eng-driven alternators, until N2 falls below 15% on shutdown.
MF