Posted on July 13, 2018 at 07:54this is code below for usart2 communication but i could not see anything on putty.please where is the wrong in the code
#include 'stm32f7xx.h' // Device header
#include<stdint.h>
#include 'Board_LED.h'
#include <string.h>
#include <stdio.h>
int rec_data();
void send_data(char s);
void delay();
void flash_led();
void PutString( uint8_t * str);
int main()
{
// int a, n;
// float b;
LED_Initialize();
//flash_led();
//usart_snd_str('\n\rHello, please type something\n\r');
//reset clock reg
RCC -> AHB1ENR |= RCC_AHB1ENR_GPIODEN;
//reset and clock control reg ,select USART2 for APB1, pin no 18
RCC -> APB1ENR =RCC_APB1ENR_USART2EN;
// mode pd8- tx and pd9 - rx
GPIOA -> MODER &= ~(GPIO_MODER_MODER1_0);
GPIOA -> MODER |= GPIO_MODER_MODER1_1;
//alternate function A7
// GPIOA->AFR[0] |= 0x77 << (4*5);
//type of gpio alternate function
GPIOA -> OTYPER &= ~(GPIO_OTYPER_OT_2);
GPIOA -> OTYPER &= ~(GPIO_OTYPER_OT_3);
//speed
GPIOA -> OSPEEDR |= GPIO_OSPEEDER_OSPEEDR1;
//push pull resisitor
GPIOA -> PUPDR &= ~(GPIO_PUPDR_PUPDR1);
//uart_configration();
// start bit
//data word length 7 , 8 and 9
//stop 2 nd 1
//baud rate 9600
//parity bits
//mode
USART2 -> CR1 &= ~USART_CR1_M0;
USART2 -> BRR = 9600;
USART2 -> CR2 &= ~(USART_CR2_STOP_1);
USART2 -> CR1 &= ~(USART_CR1_OVER8);
USART2 -> CR1 |= (USART_CR1_TE | USART_CR1_RE );
USART2 -> CR1 |= USART_CR1_UE;
uint8_t a= 12;
PutString(&a);
}
void PutChar(int8_t ch)
{
while(!(USART2->ISR & USART_ISR_TXE));
USART2->TDR = ch;
}
void PutString( uint8_t * str)
{
while(*str != 0)
{
PutChar( *str);
str++;
}
}
int rec_data()
{
/* Wait until the data is ready to be received. */
while (!(USART2->ISR & USART_ISR_RXNE));
// read RX data, combine with DR mask (we only accept a max of 9 Bits)
return ((uint8_t)(USART2->RDR & 0xFF));
}
void flash_led()
{
LED_On(1);
delay();
LED_Off(1);
delay();
}
void delay()
{
for(int i=0;i<500000;i++);
}
