Help with project

Need help with a project. Trying to detect the inputs of 5 to 7 Photoelectric Cells (PE's). Using these analog inputs, i would like to control a stepper motor to move as the strength of the PE inputs change. Can this be done with the UNO only? Very new to this so any inputs would be greatly apprciated. No pun intended.

Seven analogue inputs might be tricky without extra hardware, but six is doable.

5 is what I will use then. Will I be able to control the Stepper motor directly from the UNO?

No, you'll need some external drivers. The output pins can't handle enough current to drive a stepper.

yes you can control a stepper motor directly from the arduino you simply need some transistors connected to pwm pins and use any stepper motor library to simplify things ,http://arduino.cc/en/Tutorial/StepperUnipolar has a great example

yes you can control a stepper motor directly from the arduino you simply need some transistors connected to pwm pins

Stepper motors are not driven by PWM. You can connect the stepper motor to any pins, via transistors, but a stepper driver board is much easier.

to drive stepper motors at fast speeds the step pulse has to be pulsed quite fast , and the pwm pins can toggle faster than regular digital pins

and the pwm pins can toggle faster than regular digital pins

No, they can't. There are ways other than digitalWrite() to set a digital pin. Direct port manipulation is what PWM uses. But any pin is capable of being toggled that way.

Stepper motors are not intended to turn at high speeds. If you need high speeds, a stepper motor is not the right choice.

in terms of waht you need to dive the stepper: if you have a unipolar stepper, then you can use a simple uln2004. with a bipolar you can use a H-bridge. see here for both: http://arduino.cc/en/Reference/Stepper