我需要在APP中切换sclk_lf 的输入源,想通过改变CTL0寄存器的SCLK_LF_SRC_SEL值来切换,但都不成功;

uint32_t count1 = HWREG( AON_RTC_BASE + AON_RTC_O_SEC ) ;
uint32_t regist1 = HWREG( AUX_DDI0_OSC_BASE + DDI_0_OSC_O_CTL0 ) ;
Display_printf(dispHandle, 0, 0, "AON_RTC_O_SEC = %d",count1);
Display_printf(dispHandle, 0, 0, "CTL0 = %x",regist1);
HWREG( AUX_DDI0_OSC_BASE + DDI_0_OSC_O_CTL0 ) = regist1&0xFFFFFFF3+0xFFFFFFF8;
BIM文件的CCFG已修改为:

LF的SCLK转换不成功不知是什么原因?
