I am trying to understand the principles of a RC charging / discharging circuit however I'm at loss regarding certain aspects of its operation.

I have a square wave generator giving 0v to 5V levels at certain frequency, say 1Khz at 50% duty cycle. My R = 3.3K and C = 100nf.

My thinking is that if the capacitor charges during the high state of the generator and discharges equally during the low state of the generator. Then it shouldn't have any charge left and should remain at that level(uncharged). However when I try it practically I find that eventually the capacitor charges to some mid level, that is 2V which my mind can't really comprehend.

Does the capacitor charge and discharge and different rates in an RC circuit what exactly is going on over then I can't really explain, can you?