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STM32F0308-DISCOVERY RTC (32khz Osc)

Question asked by Lesueur.Rick on Mar 13, 2014
Latest reply on Mar 13, 2014 by Lesueur.Rick
I am attempting to utilize the RTC on STM32F0308-Discovery board. I imported this code from the SMT32f standard peripheral library. However, while attempting to debug, the code hangs on command 

 /* Wait till LSE is ready */  
  while(RCC_GetFlagStatus(RCC_FLAG_LSERDY) == RESET)

In doing some research this LSERDY != RESET when the 32.768khz crystal is stable.  So my thoughts are that this is a hardware problem, perhaps the missing XTAL3 on discovery board? 

In checking the schematic, I found part# MC306-G-06Q-32.768 (JFVNY) referenced. However, I cannot find that part or an equivalent anywhere, the closest I could find was Digikey PN CTX1178TR-ND,  CTS Frequency Controls, TC32C5132K7680. ($1.20) However, I am not sure if this is the same as part refenenced as the schematic shows a ckt with resistors/caps from/to each pin, this part appears to be the same footprint, but not sure if is functionally equivalent. 

Is there another way to implement the RTC (I need a 36 hour timer) accurate to +/- 10 or less secs per 24 hours. (Perhaps external RC ckt to pins PC 14/ PC 15?

I thank you in advance.