Maximum number of Servos in program ?

so i expected the number of operatable servos with arduino UNO to be 12 . so i wrote a program to test this , when the number of servos is 5 everything works fine , now when i add two servos or even one other . it get's messed up and even the first 5 servos wont work properly . can this be explained ?

What is the power supply for the servos?

(Hint: one wrong answer is "the Arduino")

992 with these devices. https://www.adafruit.com/products/815

so i wrote a program to test this

Please post the program.

amine2: so i expected the number of operatable servos with arduino UNO to be 12 .

It is.

so i wrote a program to test this , when the number of servos is 5 everything works fine , now when i add two servos or even one other . it get's messed up and even the first 5 servos wont work properly . can this be explained ?

Yes, inadequate power. 95% of problems people have with servos is down to inadequate power, 12 servos takes a lot of amps.

thank you very much guys , it turned out to be a simple programming mistake . sorry .