Which one is the working Due version?

Hardware Arduino Due
75

Markus_L811:
And the Story goes on,

I have buy just for fun an secound Due from ebay. And now there are the diff.

On the Due from ebay is everything the same, the box, the sticker and the package insert it looks in all way like the actuell one with all labels on the surface, except one part it has the Crystal for the RTC on the surface.

With this I have make an test I used stimmers Sketch for the Which one is the working Due version? - #33 by stimmer - Arduino Due - Arduino Forum RTC and put this in the void setup to use the external Crystal.

#define SUPC_KEY   0xA5u

void setup() {
  Serial.begin(9600);
  SUPC->SUPC_CR |= SUPC_CR_KEY(SUPC_KEY) | SUPC_CR_XTALSEL;
}




So there we are if I used the internal RC the RTC lost 5sec in 1 Min so it is nearly 10% to slow with the external Crystal is goes sync with my PC clock.

I have exactly the same Due without RTC oscillator. Could anybody point me to the reference design (eagle file) for that exact board?