Question
STM32G431 PLL settings to get 170MHz
I have been working on a self learning project with STM32G431 controller. I am having trouble switching on the PLL to get 170MHz.
When I use the CubeIDE, I get the 170MHz clock.
Given below is my code on how I am trying to Initialize the PLL
//PLL settings to set the system clock to 170MHZ
void SystemClockConfig_170MHz()
{
//Turn ON HSE and wait for it become ready
RCC->CR |= RCC_CR_HSEON;
while(!(RCC->CR & RCC_CR_HSERDY));
RCC->CR |= RCC_CR_CSSON;
//Turn OFF PLL before configuring PLL CFGR register
RCC->CFGR &= ~(RCC_CR_PLLON);
RCC->PLLCFGR = 0x00000000;
//Configure PLL to 170MHz
RCC->PLLCFGR |= RCC_PLLCFGR_PLLSRC_HSE;
RCC->PLLCFGR |= 0x4 << RCC_PLLCFGR_PLLM_Pos;
RCC->PLLCFGR |= 0x44 << RCC_PLLCFGR_PLLN_Pos;
RCC->PLLCFGR |= 0x0 << RCC_PLLCFGR_PLLPEN_Pos;
RCC->PLLCFGR |= 0x0 << RCC_PLLCFGR_PLLP_Pos;
RCC->PLLCFGR |= 0x0 << RCC_PLLCFGR_PLLQEN_Pos;
RCC->PLLCFGR |= 0x0 << RCC_PLLCFGR_PLLQ_Pos;
RCC->PLLCFGR |= 0b1 << RCC_PLLCFGR_PLLREN_Pos;
RCC->PLLCFGR |= 0b0 << RCC_PLLCFGR_PLLR_Pos;
RCC->PLLCFGR |= 0x2 << RCC_PLLCFGR_PLLPDIV_Pos;//
//Set Flash Wait latency to 4
FLASH->ACR |= FLASH_ACR_LATENCY_4WS;
//Turn ON PLL and Wait
RCC->CR |= RCC_CR_PLLON;
while(!(RCC->CR & RCC_CR_PLLRDY));
//Switch to PLL
RCC->CFGR |= RCC_CFGR_SW_PLL;
while((RCC->CFGR & RCC_CFGR_SWS) != RCC_CFGR_SWS_PLL);
}