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Hydra (With Crystal soldered on) Losing time


#1

So, last night, I set the Hydra to the proper time. The RTC is as of now, 2 hours and 24 minutes slow.

The crystal is ( http://www.mouser.com/ProductDetail/Citizen-Finetech-Miyota/CFS206-32768KDZF-UB/?qs=6siQ5y5nVCyohGPhfrXfHw== )

Am I missing something? I have not powered it down. Should there be a high-priority thread that handles the sync of the RTC?


#2

I would check the processor datasheet to verify the Crystal and the two related capacitors.


#3

I’ve seen this using a 6pF cap instead of the correct 12pF one.

My boards don’t have any capacitors as I use the MAX1338 and it doesn’t need them but the Hydra processor needs them. As you crystal is 12.5pF, I would check, as Gus suggested, the capacitors on the board are correct.


#4

Per Gus:
https://www.ghielectronics.com/community/forum/topic?id=6993

The crystal I bought

So, I take it that it it not, in fact, alright?


#5

That crystal you are using requires 12.5pF capacitors. The Hydra board comes populated with 27pF capacitors for C21 and C22, so you need to change them. Since there aren’t actually any 12.5pF caps, I used 12pF (CL10C120JB8NNNC).