Hi Tsaitgaist,
I removed the PLL part and used only 6 out of 8
contacts from the SC
https://file.tsaitgaist.info/www/?a=d&i=LqeRpJ14RJ
I have no experience with ARM microcontrollers, but
according to the datasheet VDDPLL powers the oscillator, you should
not leave it unconnected. VDDCORE powers the internal logic and
is specified as 1.65V to 1.95V.
Your "PWR_FLAG" signal connects the output of the 1.8V regulator
with +5V USB. This will most likely fry the chip as soon as power
is applied.
Have a look at ยง5.4 of the Atnek AT81SAN7S512 datasheet dated 2010-08-30.
Please don't order PCBs until one of the more ARM savy guys has had
a thorough look over your design.
Chris