Deductions & credits

This is my first time using Fidelity Charitable vs. sending cash directly.  I donated Stock into Fidelity Charitable vs. cash the stock and send the money, but the donation immediately gets sold and converted to cash, which I then targeted where I wanted it to go.  So in Turbotax, I entered Fidelity Charitable, and Stock, and the value - but it's also asking for the basis (I thought that the basis didn't matter for this type of giving).  Further, even though I don't qualify to itemize, I was still anticipating that I'd at least get the $300 "above the line" tax deduction for the donation, but nothing changed in what I owe.  Does this mean that giving stock (even though it converts to cash) doesn't count toward the $300 donation of cash, and that the only way to get a tax credit for this is to itemize?  That's not how I was hoping this would work, but at least I'm hoping someone can set me straight on how a Giving Fund donation of Stock does or does not apply to the $300 "above the line" donation credit.