#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <stm32c0xx_hal.h>
// ST Nucleo Green user LED (PA5)
#define LED_PORT GPIOA
#define LED_PIN GPIO_PIN_5
#define LED_PORT_CLK_ENABLE __HAL_RCC_GPIOA_CLK_ENABLE
UART_HandleTypeDef huart2;
void SystemClock_Config(void);
static void MX_USART2_UART_Init(void);
void initGPIO()
{
GPIO_InitTypeDef GPIO_Config;
GPIO_Config.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_Config.Pull = GPIO_NOPULL;
GPIO_Config.Speed = GPIO_SPEED_FREQ_HIGH;
GPIO_Config.Pin = LED_PIN;
LED_PORT_CLK_ENABLE();
HAL_GPIO_Init(LED_PORT, &GPIO_Config);
__HAL_RCC_GPIOA_CLK_ENABLE();
}
int main(void)
{
HAL_Init();
SystemClock_Config();
initGPIO();
MX_USART2_UART_Init();
printf("Hello, %s!\n", "Wokwi");
char received;
while (1)
{
if (HAL_UART_Receive(&huart2, (uint8_t *)&received, 1, HAL_MAX_DELAY) == HAL_OK)
{
if (received == '1') // Toggle LED on 't' received
{
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_5, GPIO_PIN_SET);
}
else if(received == '0')
{
HAL_GPIO_WritePin(GPIOA, GPIO_PIN_5, GPIO_PIN_RESET);
}
}
}
return 0;
}
/**
@brief System Clock Configuration
@retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
/** Initializes the RCC Oscillators according to the specified parameters
in the RCC_OscInitTypeDef structure.
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.HSIDiv = RCC_HSI_DIV1;
RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}
/** Initializes the CPU, AHB and APB buses clocks
*/
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_SYSCLK
| RCC_CLOCKTYPE_PCLK1;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
RCC_ClkInitStruct.SYSCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.AHBCLKDivider = RCC_HCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_APB1_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_1) != HAL_OK)
{
Error_Handler();
}
}
/**
@brief USART2 Initialization Function
@param None
@retval None
*/
static void MX_USART2_UART_Init(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
__HAL_RCC_GPIOA_CLK_ENABLE();
// PA2 ------> USART2_TX
// PA3 ------> USART2_RX
GPIO_InitStruct.Pin = GPIO_PIN_2|GPIO_PIN_3;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
GPIO_InitStruct.Alternate = GPIO_AF1_USART2;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
huart2.Instance = USART2;
huart2.Init.BaudRate = 115200;
huart2.Init.WordLength = UART_WORDLENGTH_8B;
huart2.Init.StopBits = UART_STOPBITS_1;
huart2.Init.Parity = UART_PARITY_NONE;
huart2.Init.Mode = UART_MODE_TX_RX;
huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;
huart2.Init.OverSampling = UART_OVERSAMPLING_16;
huart2.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;
huart2.Init.ClockPrescaler = UART_PRESCALER_DIV1;
huart2.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;
if (HAL_UART_Init(&huart2) != HAL_OK)
{
Error_Handler();
}
}
void Error_Handler(void)
{
/* User can add his own implementation to report the HAL error return state */
}
// The following makes printf() write to USART2:
#define STDOUT_FILENO 1
#define STDERR_FILENO 2
int _write(int file, uint8_t *ptr, int len)
{
switch (file)
{
case STDOUT_FILENO:
HAL_UART_Transmit(&huart2, ptr, len, HAL_MAX_DELAY);
break;
case STDERR_FILENO:
HAL_UART_Transmit(&huart2, ptr, len, HAL_MAX_DELAY);
break;
default:
return -1;
}
return len;
}