ADP Run Logic on 747-400

[QAVION]

I seem to recall a previous question on this subject, but can't
seem to find it...

On some 747-400's, the ADP's are activated by "Flaps In Motion"
and "Flaps Out of UP signals" (amongst other things). What
generates these signals?

Flap Position transmitters (L/E? I/B TE? O/B TE Flap?)
Flap I/P actuator feedback?
Flap Lever RVDT's?
A combination of these?

I understand that a specific Flap Control Computer handles each
ADP and that there is no FCU redundancy for ADP control. i.e. The
Right FCU only handles the #1 ADP and the Left FCU handles
only the #4 ADP. Is this correct?

Thanks.
Regards.
Q.