#include<main.h>
#include<stdarg.h>
void SystemInit();
void Uart1_config();
void uart_printf(const char *fmt, ...);
void delay(int val);
void Gpio_Enable();
void USART1_IRQHandler()
{
uint16_t rx;
rx=USART1->DR;
GPIOB->ODR ^=1<<3;
USART1->SR=0;
}
void SystemInit()
{
RCC->CR|=RCC_HSION;
RCC->APB1ENR|=RCC_PWREN;
PWR->CR|=PWR_VOS;
RCC->CFGR|=RCC_SW;
}
char buf[512];
void uart_printf(const char *fmt, ...)
{
int ret;
va_list args;
va_start(args, fmt);
ret = vsnprintf(buf, 512, fmt, args);
va_end(args);
if (ret > 0)
{
for (int i =0; i < ret; i++)
{
USART1->SR = 0;
USART1->DR = buf[i];
while(!(USART1->SR & (1<<6)) );
}
}
}
void Uart1_config()
{
RCC->APB2ENR |=USART1_CLK;
RCC->AHB1ENR |=1;
GPIOA->MODER |=2<<18;/* Enabling Mode of PA9 */
GPIOA->MODER |=2<<20;/*Enabling Mode of PA9 */
GPIOA->OSPEEDR |=3<<18;/* Enabling High speed of PA9*/
GPIOA->OSPEEDR |=3<<20;/* Enabling High speed of PA10*/
GPIOA->AFR[1] |=7<<4;/*Enabling AFR7 of PA9 */
GPIOA->AFR[1] |=7<<8;/*Enabling AFR8 of PA10 */
USART1->CR1 |=USART1_EN;
USART1->BRR =((3<<0) | (0x68<<4)); /*9600 Baud Rate*/
USART1->CR1 |=USART1_RE;
USART1->CR1 |=USART1_TE;
USART1->CR1 |=1<<5;/*RXNEIE: RXNE interrupt enable*/
NVIC->ISER1|=1<<6;/*USART1 IRQ PRIORITY IS 37th*/
}
void Gpio_Enable()
{
RCC->AHB1ENR |=2;
GPIOB->MODER =1<<6;/* Enabling O/p Mode of PB3*/
}
int main()
{
SystemInit();
Uart1_config();
Gpio_Enable();
GPIOB->ODR |=(1<<3);
while(1)
{
}
}
void delay(int val)
{
RCC->APB1ENR |= 2;//ENABLE TIMER 3
TIM3->PSC=160;
TIM3->EGR=1;/*Update generation in TIM3_EGR */
TIM3->CR1=1;/*Enable Timer 3*/
TIM3->CNT=0;
while(TIM3->CNT < val);
TIM3->SR=0;
}
USART1_IRQ HANDLER ISR is not getting executing when UART is Receiving.
