Question
UART configuration directly with registers, NUCLEO-H563ZI board
I am using the NUCLEO-H563ZI board and I am trying to configure the UART2 using only registers.
I started by creating a fresh and simple new code with STM32CubeIDE for UART transmit because I wanted to use a simple uart_transmit function but I had trouble making it work until I activated the USB as Host_Only from the .ioc
Pinout & Configuration and only then was I able to use the HAL_UART_Transmit to send a text to a terminal and I would like to know why that is.
Then I want to be able to configure the UART2 directly with the registers but then the code breaks how can I make this work? Thank you.
/* USER CODE BEGIN Header */
/**
******************************************************************************
* @file : main.c
* @brief : Main program body
******************************************************************************
* @attention
*
* Copyright (c) 2024 STMicroelectronics.
* All rights reserved.
*
* This software is licensed under terms that can be found in the LICENSE file
* in the root directory of this software component.
* If no LICENSE file comes with this software, it is provided AS-IS.
*
******************************************************************************
*/
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "app_usbx_host.h"
/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
/* USER CODE END Includes */
/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */
/* USER CODE END PTD */
/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* USER CODE END PD */
/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */
/* USER CODE END PM */
/* Private variables ---------------------------------------------------------*/
UART_HandleTypeDef huart2;
HCD_HandleTypeDef hhcd_USB_DRD_FS;
/* USER CODE BEGIN PV */
/* USER CODE END PV */
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_ICACHE_Init(void);
static void MX_USART2_UART_Init(void);
static void MX_USB_HCD_Init(void);
/* USER CODE BEGIN PFP */
uint8_t data[] = "HELLO WORLD \r\n";
/* USER CODE END PFP */
/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart)
{
HAL_UART_Transmit (&huart2, data, sizeof (data), 1000);
}
/* USER CODE END 0 */
/**
* @brief The application entry point.
* @retval int
*/
int main(void)
{
/* USER CODE BEGIN 1 */
/* USER CODE END 1 */
/* MCU Configuration--------------------------------------------------------*/
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_ICACHE_Init();
MX_USART2_UART_Init();
MX_USB_HCD_Init();
MX_USBX_Host_Init();
/* USER CODE BEGIN 2 */
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
HAL_UART_Transmit (&huart2, data, sizeof (data), 1000);
HAL_Delay (1000);
}
/* USER CODE END 3 */
}
/**
* @brief System Clock Configuration
* @retval None
*/
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
/** Configure the main internal regulator output voltage
*/
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE0);
while(!__HAL_PWR_GET_FLAG(PWR_FLAG_VOSRDY)) {}
/** Initializes the RCC Oscillators according to the specified parameters
* in the RCC_OscInitTypeDef structure.
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI48|RCC_OSCILLATORTYPE_CSI;
RCC_OscInitStruct.HSI48State = RCC_HSI48_ON;
RCC_OscInitStruct.CSIState = RCC_CSI_ON;
RCC_OscInitStruct.CSICalibrationValue = RCC_CSICALIBRATION_DEFAULT;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLL1_SOURCE_CSI;
RCC_OscInitStruct.PLL.PLLM = 1;
RCC_OscInitStruct.PLL.PLLN = 125;
RCC_OscInitStruct.PLL.PLLP = 2;
RCC_OscInitStruct.PLL.PLLQ = 2;
RCC_OscInitStruct.PLL.PLLR = 2;
RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1_VCIRANGE_2;
RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1_VCORANGE_WIDE;
RCC_OscInitStruct.PLL.PLLFRACN = 0;
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_CLOCKTYPE_PCLK2
|RCC_CLOCKTYPE_PCLK3;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
RCC_ClkInitStruct.APB3CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5) != HAL_OK)
{
Error_Handler();
}
}
/**
* @brief ICACHE Initialization Function
* None
* @retval None
*/
static void MX_ICACHE_Init(void)
{
/* USER CODE BEGIN ICACHE_Init 0 */
/* USER CODE END ICACHE_Init 0 */
/* USER CODE BEGIN ICACHE_Init 1 */
/* USER CODE END ICACHE_Init 1 */
/** Enable instruction cache (default 2-ways set associative cache)
*/
if (HAL_ICACHE_Enable() != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN ICACHE_Init 2 */
/* USER CODE END ICACHE_Init 2 */
}
/**
* @brief USART2 Initialization Function
* None
* @retval None
*/
static void MX_USART2_UART_Init(void)
{
/* USER CODE BEGIN USART2_Init 0 */
RCC->AHB2ENR |= RCC_AHB2ENR_GPIODEN; // ENABLE GPIO PORT D CLOCK (BIT 0)
RCC->APB1LENR |= RCC_APB1LENR_USART2EN; // ENABLE UART2 CLOCK (BIT 14)
///*
GPIOD->MODER &= ~((3u << 10) // CLEAR PD5
|(3u << 12)); // CLEAR PD6
// SET PIN MODES
GPIOD->MODER |= ((2u << 10) // SET PD5 TO AF
|(2u << 12)); // SET PD6 TO AF
GPIOD->AFR[2] &= ~((15u << 20) // CLEAR PD5 AF
|(15u << 24)); // CLEAR PD6 AF
// SET ALTERNATE FUNCTION
GPIOD->AFR[2] |= ((7u << 20) // SET PD5 AF
|(7u << 24)); // SET PD6 AF
//*/
USART2->CR1 &= ~(USART_CR1_M1 // CLEAR M1 FOR 1 START BIT AND 8 DATA BITS (28)
|(0x03 << 26) // INHIBIT INTERRUPTS AT BITS 26 AND 27 (27/26)
|USART_CR1_OVER8 // OVERSAMPLING BY 16 (15)
|USART_CR1_CMIE // INHIBIT CHARACTER MATCH INTERRUPT (14)
|USART_CR1_MME // DON'T ENABLE MUTE MODE (13)
|USART_CR1_M0 // CLEAR M0 FOR 1 START BIT AND 8 DATA BITS (12)
|USART_CR1_PCE // NOT IMPLEMENTING PARITY CONTROL (10)
|(0x1F << 3) // INHIBIT INTERRUPTS AT BITS 4 TO 8 (4-8)
|USART_CR1_TE // DON'T ENABLE TRANSMITTER JUST YET (3)
|USART_CR1_RE // DON'T ENABLE RECEIVER JUST YET (2)
|USART_CR1_UE); // DON'T ENABLE UART2 JUST YET (0)
// CONFIGURE USART CR2 REGISTER
// CLEAR BITS
USART2->CR2 &= ~(USART_CR2_RTOEN // DISABLE RECEIVER TIMEOUT (23)
|USART_CR2_ABREN // NO AUTOMATIC BAUD RATE DETECTION (20)
|USART_CR2_MSBFIRST // TRANSMIT/RECEIVE LSB FIRST (19)
|(0x03 << 16) // IDLE STATE HIGH FOR RX/TX PINS (17/16)
|USART_CR2_SWAP // DON'T SWAP FUNCTION OF RX/TX PINS (15)
|USART_CR2_LINEN // NO LIN MODE (14)
|(0x03 << 12) // 1 STOP BIT (13/12)
|USART_CR2_CLKEN // DON'T USE CLOCK WITH UART (11)
|USART_CR2_LBDIE); // NO LIN BREAK DETECTION INTERRUPT (6)
// CONFIGURE USART CR3 REGISTER
// CLEAR BITS
USART2->CR3 &= ~(USART_CR3_TCBGTIE // NO TRANSMISSION COMPLETE BEFORE GUART TIME INTERRUPT (24)
|USART_CR3_DEM // NO DRIVER ENABLE MODE (14)
|(0x7F << 3) // DISABLE VARIOUS IRRELEVANT MODES (9-3)
|USART_CR3_IREN // NO IrDA MODE (1)
|USART_CR3_EIE); // INHIBIT ERROR INTERRUPT (0)
// SET BITS
USART2->CR3 |= (USART_CR3_OVRDIS // DISABLE OVERRUN FUNCTIONALITY (12)
|USART_CR3_ONEBIT); // USE ONE SAMPLE BIT METHOD (11)
// SET BAUD RATE IN BRR REGISTER
USART2->BRR = 2170;
// VALUE THAT SETS BAUD RATE TO 115,200 AT INPUT FREQUENCY OF 4MHZ
// ENABLE UART
USART2->CR1 |= (USART_CR1_TE // ENABLE TRANSMITTER (3)
|USART_CR1_RE // ENABLE RECEIVER (2)
|USART_CR1_UE); // ENABLE UART2 (0)
/*
USART2->CR1 = 0x00; // Clear ALL
USART2->CR1 |= (1<<13); // UE = 1... Enable USART
USART2->BRR = 2170; // Baud rate of 115200, PCLK1 at 45MHz
USART2->CR1 |= (1<<2); // RE=1.. Enable the Receiver
USART2->CR1 |= (1<<3);
*/
/* USER CODE END USART2_Init 0 */
/* USER CODE BEGIN USART2_Init 1 */
/* USER CODE END USART2_Init 1 */
/*
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();
}
if (HAL_UARTEx_SetTxFifoThreshold(&huart2, UART_TXFIFO_THRESHOLD_1_8) != HAL_OK)
{
Error_Handler();
}
if (HAL_UARTEx_SetRxFifoThreshold(&huart2, UART_RXFIFO_THRESHOLD_1_8) != HAL_OK)
{
Error_Handler();
}
if (HAL_UARTEx_DisableFifoMode(&huart2) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN USART2_Init 2 */
/* USER CODE END USART2_Init 2 */
}
/**
* @brief USB Initialization Function
* None
* @retval None
*/
static void MX_USB_HCD_Init(void)
{
/* USER CODE BEGIN USB_Init 0 */
/* USER CODE END USB_Init 0 */
/* USER CODE BEGIN USB_Init 1 */
/* USER CODE END USB_Init 1 */
hhcd_USB_DRD_FS.Instance = USB_DRD_FS;
hhcd_USB_DRD_FS.Init.dev_endpoints = 8;
hhcd_USB_DRD_FS.Init.Host_channels = 8;
hhcd_USB_DRD_FS.Init.speed = USBD_FS_SPEED;
hhcd_USB_DRD_FS.Init.phy_itface = HCD_PHY_EMBEDDED;
hhcd_USB_DRD_FS.Init.Sof_enable = DISABLE;
hhcd_USB_DRD_FS.Init.low_power_enable = DISABLE;
hhcd_USB_DRD_FS.Init.vbus_sensing_enable = DISABLE;
hhcd_USB_DRD_FS.Init.bulk_doublebuffer_enable = DISABLE;
hhcd_USB_DRD_FS.Init.iso_singlebuffer_enable = DISABLE;
if (HAL_HCD_Init(&hhcd_USB_DRD_FS) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN USB_Init 2 */
/* USER CODE END USB_Init 2 */
}
/**
* @brief GPIO Initialization Function
* None
* @retval None
*/
static void MX_GPIO_Init(void)
{
/* USER CODE BEGIN MX_GPIO_Init_1 */
/* USER CODE END MX_GPIO_Init_1 */
/* GPIO Ports Clock Enable */
__HAL_RCC_GPIOH_CLK_ENABLE();
__HAL_RCC_GPIOA_CLK_ENABLE();
__HAL_RCC_GPIOD_CLK_ENABLE();
/* USER CODE BEGIN MX_GPIO_Init_2 */
/* USER CODE END MX_GPIO_Init_2 */
}
/* USER CODE BEGIN 4 */
/* USER CODE END 4 */
/**
* @brief This function is executed in case of error occurrence.
* @retval None
*/
void Error_Handler(void)
{
/* USER CODE BEGIN Error_Handler_Debug */
/* User can add his own implementation to report the HAL error return state */
__disable_irq();
while (1)
{
}
/* USER CODE END Error_Handler_Debug */
}
#ifdef USE_FULL_ASSERT
/**
* @brief Reports the name of the source file and the source line number
* where the assert_param error has occurred.
* file: pointer to the source file name
* line: assert_param error line source number
* @retval None
*/
void assert_failed(uint8_t *file, uint32_t line)
{
/* USER CODE BEGIN 6 */
/* User can add his own implementation to report the file name and line number,
ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
/* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */