Hi,
Can you just make some code to control ONE servo, use a pot on an analog pin to control it?
Then add another servo and code and see if both sweep with the pot.
Keep adding servos and adding code, see if your servos move in sequence.
Ultimately you should have 7 servos all moving in sync.
That will test if your attach and servo position commands work and that you have enough power for the servos.
A very important question! What are you using to power the servos?
Do you have a DMM?
Don't use serial commands for this test.
Tom... 