I am trying to design a real-time clock circuit using a 32.768 KHz oscillator. I have no access to a datasheet for the microcontroller that I am using, but I know it requirese a 330K resistor and an oscillator of this frequency. I decided to use a 12.5 pF crystal, so I estimated 15 pF for the loading capacitors.
This is only a 2 layer board, and the copper pour on the underside of the crystal (Y1) is grounded. A thick trace can be seen underneath C4 and R1, this is a power line that powers the controller (can be 3.3v or 5v). Trace widths between crystal and controller are .17 mm.
The problem is that my real time clock is not "ticking". I have narrowed the issue down to this circuit. If I have made some obvious mistake, I apologize. I am no engineer.
Crystal Datasheet (CFS-206): https://www.mouser.com/datasheet/2/77/CFS-145%20CFS-206%20CFV-206_E-1131372.pdf