Magnetize pen on custom grid

Hello,

I'm doing an illustration in pixel art mode. I would like to be able to magnetize my pen tool on a custom grid.

I made a grid that cuts my image in 10px increments. But I can't make my 10px pen follow the grid.

Here's what I got:

Here's what I would like: Is it possible to get this under Photoshop?

I tried to find out if anyone had ever wanted to do this but I didn't find any posts on it. If someone could tell me how to solve my problem.

Thank you.

PS: I'm on Photoshop CC 2015

Fixed by disabling the spacing It doesn't magnetize on the exact square but on the intersection but it's enough.