xbee s2c speed control

i want to control intensity and speed control of my applinces , i want to do without using potentiometer , like volume button of our tv pls help me.

That would be an analog input and a PWM output.

yes but how i can change it, pls explain in detail.

May I suggest you read over http://knowledge.digi.com/articles/Knowledge_Base_Article/Analog-to-Digital-Conversion-on-the-XBee-802-15-4/?q=analog+to+digital+conversion&l=en_US&fs=Search&pn=1 and