if I manualy set the SCU->PCGR0 in the code (instead of using library functions) I got error that SCU_TypeDef doesn't have member PCGR0. I think that SCU_TypeDef doesn't declare PCGR with zero but capital letter o. Same thing applies to SCU_AHBPeriphClockConfig where SCU->PCGR0 is used (and other lines of code where SCU->PCGR0 is used).