/* This function enable frequency output function and configure frequency clock source and divider.  */
void CLK_EnableCKO(uint32_t u32ClkSrc, uint32_t u32ClkDiv, uint32_t u32ClkDivBy1En)
/* This function enable frequency output function and configure frequency clock source and divider.  */
void CLK_EnableCKO(uint32_t u32ClkSrc, uint32_t u32ClkDiv, uint32_t u32ClkDivBy1En)
{
    CLK->CLKOCTL = CLK_CLKOCTL_CLKOEN_Msk | u32ClkDiv | (u32ClkDivBy1En << CLK_CLKOCTL_DIV1EN_Pos);
    CLK->APBCLK0 |= CLK_APBCLK0_CLKOCKEN_Msk;
    CLK->CLKSEL1 = (CLK->CLKSEL1 & (~CLK_CLKSEL1_CLKOSEL_Msk)) | (u32ClkSrc);
}