Posted on September 28, 2015 at 21:10I have been trying to get my code to work but I cannot get any output on PA9 (USART1_Tx) on my STM32f0discovery board. Any help would be greatly appreciated.
CODE ==========================================================
void InitUART() {
// RCC Setup
RCC->CFGR = 0;
RCC->CFGR3 &= 0xFFFFFFFC;
RCC->APB2ENR |= (1<<14);
RCC->AHBENR |= (1<<17);
// GPIO Setup
GPIOA->MODER &= 0xFFC3FFFF; GPIOA->MODER |= 0x00280000L;
GPIOA->OSPEEDR = 0x003c0000;
GPIOA->OTYPER = 0;
GPIOA->PUPDR &= 0xFFC3FFFF; GPIOA->PUPDR|=0x00140000; // Pull up on both lines
// USART Setup
USART1->CR2 = 0;
USART1->CR3 = 0;
USART1->BRR = 69; // 8MHz clock, 115200 rate
USART1->GTPR = 1;
USART1->RTOR = 0;
USART1->RQR = 0;
USART1->CR1 = USART_CR1_RE | USART_CR1_TE | USART_CR1_UE;
}
void SendByte(unsigned char b) {
while ((USART1->ISR & USART_ISR_TXE) == 0);
USART1->TDR=b;
while ((USART1->ISR & USART_ISR_TXE) == 0);
}
int main() {
InitUART();
for(;;) {
SendByte(0xF0);
SendByte(0x55);
for(i=0;i<50;i++) ;
}
}
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#usart-stm32f051
