[STM32H750B-DK] Ethernet peripheral not responding - DMACSR reads 0 after all attempts

ksale.1 · ‎2026-03-03

Hello everyone,

I've been working on getting Ethernet working on the STM32H750B-DK discovery board with TouchGFX and LwIP. After extensive debugging, I suspect a hardware issue and would appreciate your advice on confirming this.

What Works ✓

TouchGFX display runs perfectly
USART3 debug output works (Tera Term shows messages)
PHY communication works (we get "Link established!")

The Problem ✗

The Ethernet MAC peripheral itself appears completely dead. We've tried:

1. Direct MDIO Access Works

Successfully read PHY registers
PHY responds and reports link up
This proves MDIO/MDC pins are working

2. ETH Peripheral Shows No Life

ETH DMACSR after reset: 0x00000000
ETH DMACSR after system reset: 0x00000000

Reading ETH->DMACSR always returns 0
This register should never be 0 on a live peripheral

3. What We've Tried

Software attempts:

Enabled all ETH clocks (__HAL_RCC_ETH1MAC_CLK_ENABLE() etc.)
Forced and released peripheral reset
Tried system-level reset via RCC (RCC_AHB1RSTR_ETH1MACRST)
De-init and re-init with correct descriptors (0x30040000 etc.)
Bypassed MX_LWIP_Init() completely
Manual PHY configuration (gets link)

CubeMX configuration verified:

ETH set to RMII mode
All RMII pins correctly assigned (PA1, PA2, PA7, PC1, PC4, PC5, PG11, PG13, PG14)
LAN8742 PHY selected
Linker script has proper .lwip_sec section at 0x30040000

4. The Smoking Gun

ETH DMACSR after reset: 0x00000000
ETH still not responding - trying system reset
ETH DMACSR after system reset: 0x00000000
ETH HAL Init FAILED with error: 1

The DMACSR register should never read 0 on a working peripheral. Even with no link, it should return a non-zero value.

Questions for the Community

Is DMACSR = 0 definitive proof of dead hardware? What else could cause this?
Are there any jumpers or solder bridges on the STM32H750B-DK that need to be closed for Ethernet to work?
What should DMACSR read on a properly functioning STM32H750? (Even with no cable?)
Any way to verify if the ETH peripheral is getting power/clocks?
Could this be a faulty chip/board? The board is new and the display works perfectly.
Is there a factory demo that uses Ethernet I can flash to confirm hardware works?

What We See in Debug Output

Pre-RTOS: UART is working!
About to start RTOS...
LWIP task STARTING...
Manually configuring PHY...
Link established!
ETH power-up sequence...
All ETH clocks enabled
ETH reset released
ETH DMACSR after reset: 0x00000000
ETH still not responding - trying system reset
ETH DMACSR after system reset: 0x00000000
RxDesc: 0x30040000, TxDesc: 0x30040100, RxBuffLen: 1536
ETH HAL Init FAILED with error: 1
Setting up network interface...
IP set to: 192.168.1.110
Network interface is UP
Starting echo servers...
Heartbeat #0 - IP: 192.168.1.110

Any help would be greatly appreciated! I've spent days on this and suspect hardware failure, but want to be certain before replacing the board.

Board: STM32H750B-DK DK32H760B$AT1
CubeMX Version: 6.16.0
TouchGFX Version: 4.26.0
Ethernet PHY: LAN8742 (onboard)

Thanks in advance!

ksale.1 · ‎2026-03-05

Given that the working example uses MII mode and my board is the same model, my board almost certainly uses MII mode with the PHY as clock master (example in https://github.com/stm32-hotspot/STM32H7-LwIP-Examples/tree/main/STM32H750_Disco_ETH). This means:

My 48MHz MCO experiment was misguided (wrong frequency, wrong mode)

PA1 should be receiving 25MHz from PHY, not generating 50MHz

The DMACSR=0 issue is likely due to the descriptor address mismatch we already identified, not the clock

First, I'll fix the descriptor addresses as follows:

Setting Current Should Be

ETH Mode	RMII	MII
Rx Desc Address	0x30000100	0x30040000
Tx Desc Address	0x30000100	0x30040060
Rx Buffers Address	0x30000200	0x30040200
MCO1/PA8	Configured	Remove MCO1 config
Linker Script	Has .lwip_sec	Good as is

this is the most likely cause of DMACSR=0

Revert MCO1 configuration -

set PA8 back to default/TIM function

Test again

LCE · ‎2026-03-05

If the PHY is the LAN8742A as on most ST boards, it's surely an RMII interface.

ksale.1 · ‎2026-03-05

Looking at the board schematics, it indicates MII mode:

MII Signal STM32 Pin Status

ETH_TX_CLK	PC3	✓ Configured
ETH_TX_EN	PG11	✓ Configured
ETH_TXD0	PG13	✓ Configured
ETH_TXD1	PG12	✓ Configured
ETH_TXD2	PC2	✓ Configured
ETH_TXD3	PE2	✓ Configured
ETH_RX_CLK	PA1	✓ Configured
ETH_RX_DV	PA7	✓ Configured
ETH_RXD0	PC4	✓ Configured
ETH_RXD1	PC5	✓ Configured
ETH_RXD2	PB0	✓ Configured
ETH_RXD3	PB1	✓ Configured
ETH_CRS	PA0	✓ Configured
ETH_COL	PA3	✓ Configured
ETH_MDC	PC1	✓ Configured
ETH_MDIO	PA2	✓ Configured
ETH_RX_ER	PI10	✓ Configured

ksale.1 · ‎2026-03-05

I am trying to communicate with UART3 to Tera Team, will you help verify please:

/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file           : main.c
  * @brief          : Main program body
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2022 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 "cmsis_os.h"
#include "lwip.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */
#include "lwip/apps/lwiperf.h"
#include <string.h>
#include <stdio.h>
#include "stm32h7xx_hal_uart.h"  // Specific UART header
#include "stm32h7xx_hal.h"        // Master HAL header
/* 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 ---------------------------------------------------------*/
ADC_HandleTypeDef hadc3;
UART_HandleTypeDef huart3;  // UART handle for debug output

/* Definitions for defaultTask */
osThreadId_t defaultTaskHandle;
const osThreadAttr_t defaultTask_attributes = {
  .name = "defaultTask",
  .stack_size = 512 * 4,
  .priority = (osPriority_t) osPriorityNormal,
};
/* USER CODE BEGIN PV */

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MPU_Config(void);
static void MX_GPIO_Init(void);
static void MX_ADC3_Init(void);
void StartDefaultTask(void *argument);
void MX_USART3_UART_Init(void);  // Add prototype

/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */

  /* USER CODE END 1 */

  /* MPU Configuration--------------------------------------------------------*/
  MPU_Config();

  /* Enable I-Cache---------------------------------------------------------*/
  SCB_EnableICache();

  /* Enable D-Cache---------------------------------------------------------*/
  SCB_EnableDCache();

  /* 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_ADC3_Init();
  MX_USART3_UART_Init();  // Initialize UART for debug
  /* USER CODE BEGIN 2 */

  /* USER CODE END 2 */

  /* Init scheduler */
  osKernelInitialize();

  /* USER CODE BEGIN RTOS_MUTEX */
  /* add mutexes, ... */
  /* USER CODE END RTOS_MUTEX */

  /* USER CODE BEGIN RTOS_SEMAPHORES */
  /* add semaphores, ... */
  /* USER CODE END RTOS_SEMAPHORES */

  /* USER CODE BEGIN RTOS_TIMERS */
  /* start timers, add new ones, ... */
  /* USER CODE END RTOS_TIMERS */

  /* USER CODE BEGIN RTOS_QUEUES */
  /* add queues, ... */
  /* USER CODE END RTOS_QUEUES */

  /* Create the thread(s) */
  /* creation of defaultTask */
  defaultTaskHandle = osThreadNew(StartDefaultTask, NULL, &defaultTask_attributes);

  /* USER CODE BEGIN RTOS_THREADS */
  /* add threads, ... */
  /* USER CODE END RTOS_THREADS */

  /* USER CODE BEGIN RTOS_EVENTS */
  /* add events, ... */
  /* USER CODE END RTOS_EVENTS */

  /* Start scheduler */
  osKernelStart();

  /* We should never get here as control is now taken by the scheduler */
  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */
  }
  /* USER CODE END 3 */
}

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Supply configuration update enable
  */
  HAL_PWREx_ConfigSupply(PWR_LDO_SUPPLY);

  /** Configure the main internal regulator output voltage
  */
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);

  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_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_BYPASS;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLM = 5;
  RCC_OscInitStruct.PLL.PLLN = 160;
  RCC_OscInitStruct.PLL.PLLP = 2;
  RCC_OscInitStruct.PLL.PLLQ = 4;
  RCC_OscInitStruct.PLL.PLLR = 2;
  RCC_OscInitStruct.PLL.PLLRGE = RCC_PLL1VCIRANGE_2;
  RCC_OscInitStruct.PLL.PLLVCOSEL = RCC_PLL1VCOWIDE;
  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_D3PCLK1|RCC_CLOCKTYPE_D1PCLK1;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.SYSCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_HCLK_DIV2;
  RCC_ClkInitStruct.APB3CLKDivider = RCC_APB3_DIV2;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_APB1_DIV2;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_APB2_DIV2;
  RCC_ClkInitStruct.APB4CLKDivider = RCC_APB4_DIV2;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
  {
    Error_Handler();
  }
}

/**
  * @brief ADC3 Initialization Function
  * @PAram None
  * @retval None
  */
static void MX_ADC3_Init(void)
{

  /* USER CODE BEGIN ADC3_Init 0 */

  /* USER CODE END ADC3_Init 0 */

  ADC_ChannelConfTypeDef sConfig = {0};

  /* USER CODE BEGIN ADC3_Init 1 */

  /* USER CODE END ADC3_Init 1 */

  /** Common config
  */
  hadc3.Instance = ADC3;
  hadc3.Init.Resolution = ADC_RESOLUTION_16B;
  hadc3.Init.ScanConvMode = ADC_SCAN_DISABLE;
  hadc3.Init.EOCSelection = ADC_EOC_SINGLE_CONV;
  hadc3.Init.LowPowerAutoWait = DISABLE;
  hadc3.Init.ContinuousConvMode = DISABLE;
  hadc3.Init.NbrOfConversion = 1;
  hadc3.Init.DiscontinuousConvMode = DISABLE;
  hadc3.Init.ExternalTrigConv = ADC_SOFTWARE_START;
  hadc3.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE;
  hadc3.Init.ConversionDataManagement = ADC_CONVERSIONDATA_DR;
  hadc3.Init.Overrun = ADC_OVR_DATA_PRESERVED;
  hadc3.Init.LeftBitShift = ADC_LEFTBITSHIFT_NONE;
  hadc3.Init.OversamplingMode = DISABLE;
  if (HAL_ADC_Init(&hadc3) != HAL_OK)
  {
    Error_Handler();
  }

  /** Configure Regular Channel
  */
  sConfig.Channel = ADC_CHANNEL_1;
  sConfig.Rank = ADC_REGULAR_RANK_1;
  sConfig.SamplingTime = ADC_SAMPLETIME_1CYCLE_5;
  sConfig.SingleDiff = ADC_DIFFERENTIAL_ENDED;
  sConfig.OffsetNumber = ADC_OFFSET_NONE;
  sConfig.Offset = 0;
  sConfig.OffsetSignedSaturation = DISABLE;
  if (HAL_ADC_ConfigChannel(&hadc3, &sConfig) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN ADC3_Init 2 */

  /* USER CODE END ADC3_Init 2 */

}

/**
  * @brief USART3 Initialization Function
  * @PAram None
  * @retval None
  */
void MX_USART3_UART_Init(void)
{
    huart3.Instance = USART3;
    huart3.Init.BaudRate = 115200;
    huart3.Init.WordLength = UART_WORDLENGTH_8B;
    huart3.Init.StopBits = UART_STOPBITS_1;
    huart3.Init.Parity = UART_PARITY_NONE;
    huart3.Init.Mode = UART_MODE_TX_RX;
    huart3.Init.HwFlowCtl = UART_HWCONTROL_NONE;
    huart3.Init.OverSampling = UART_OVERSAMPLING_16;
    if (HAL_UART_Init(&huart3) != HAL_OK)
    {
        Error_Handler();
    }
}

/**
  * @brief GPIO Initialization Function
  * @PAram None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
  GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOI_CLK_ENABLE();
  __HAL_RCC_GPIOB_CLK_ENABLE();
  __HAL_RCC_GPIOK_CLK_ENABLE();
  __HAL_RCC_GPIOG_CLK_ENABLE();
  __HAL_RCC_GPIOC_CLK_ENABLE();
  __HAL_RCC_GPIOE_CLK_ENABLE();
  __HAL_RCC_GPIOJ_CLK_ENABLE();
  __HAL_RCC_GPIOD_CLK_ENABLE();
  __HAL_RCC_GPIOH_CLK_ENABLE();
  __HAL_RCC_GPIOA_CLK_ENABLE();
  __HAL_RCC_GPIOF_CLK_ENABLE();

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(LD2_GPIO_Port, LD2_Pin, GPIO_PIN_RESET);

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(LD1_GPIO_Port, LD1_Pin, GPIO_PIN_RESET);

  /*Configure GPIO pin Output Level */
  HAL_GPIO_WritePin(LCD_RST_GPIO_Port, LCD_RST_Pin, GPIO_PIN_RESET);

  /*Configure GPIO pins : PI6 PI5 PI4 PI7 */
  GPIO_InitStruct.Pin = GPIO_PIN_6|GPIO_PIN_5|GPIO_PIN_4|GPIO_PIN_7;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF10_SAI2;
  HAL_GPIO_Init(GPIOI, &GPIO_InitStruct);

  /*Configure GPIO pins : FDCAN2_RX_Pin FDCAN2_TX_Pin */
  GPIO_InitStruct.Pin = FDCAN2_RX_Pin|FDCAN2_TX_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF9_FDCAN2;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

  /*Configure GPIO pins : PK5 PK4 PK6 PK3
                           PK7 PK2 */
  GPIO_InitStruct.Pin = GPIO_PIN_5|GPIO_PIN_4|GPIO_PIN_6|GPIO_PIN_3
                          |GPIO_PIN_7|GPIO_PIN_2;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF14_LTDC;
  HAL_GPIO_Init(GPIOK, &GPIO_InitStruct);

  /*Configure GPIO pin : PG10 */
  GPIO_InitStruct.Pin = GPIO_PIN_10;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF10_SAI2;
  HAL_GPIO_Init(GPIOG, &GPIO_InitStruct);

  /*Configure GPIO pins : SDIO1_D2_Pin SDIO1_D3_Pin SDIO1_CK_Pin SDIO1_D0_Pin
                           SDIO1_D1_Pin SDIO1_D7_Pin SDIO1_D6_Pin */
  GPIO_InitStruct.Pin = SDIO1_D2_Pin|SDIO1_D3_Pin|SDIO1_CK_Pin|SDIO1_D0_Pin
                          |SDIO1_D1_Pin|SDIO1_D7_Pin|SDIO1_D6_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
  GPIO_InitStruct.Alternate = GPIO_AF12_SDIO1;
  HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);

  /*Configure GPIO pins : PI1 PI0 PI9 PI12
                           PI14 PI15 */
  GPIO_InitStruct.Pin = GPIO_PIN_1|GPIO_PIN_0|GPIO_PIN_9|GPIO_PIN_12
                          |GPIO_PIN_14|GPIO_PIN_15;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF14_LTDC;
  HAL_GPIO_Init(GPIOI, &GPIO_InitStruct);

  /*Configure GPIO pins : PE1 PE0 PE10 PE9
                           PE11 PE12 PE15 PE8
                           PE13 PE7 PE14 */
  GPIO_InitStruct.Pin = GPIO_PIN_1|GPIO_PIN_0|GPIO_PIN_10|GPIO_PIN_9
                          |GPIO_PIN_11|GPIO_PIN_12|GPIO_PIN_15|GPIO_PIN_8
                          |GPIO_PIN_13|GPIO_PIN_7|GPIO_PIN_14;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
  GPIO_InitStruct.Alternate = GPIO_AF12_FMC;
  HAL_GPIO_Init(GPIOE, &GPIO_InitStruct);

  /*Configure GPIO pin : PB6 */
  GPIO_InitStruct.Pin = GPIO_PIN_6;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF10_QUADSPI;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

  /*Configure GPIO pin : PB4 */
  GPIO_InitStruct.Pin = GPIO_PIN_4;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF7_SPI2;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

  /*Configure GPIO pins : LCD_DISP_Pin PJ14 PJ12 PJ13
                           PJ11 PJ10 PJ9 PJ0
                           PJ8 PJ7 PJ6 PJ1
                           PJ5 PJ3 PJ4 */
  GPIO_InitStruct.Pin = LCD_DISP_Pin|GPIO_PIN_14|GPIO_PIN_12|GPIO_PIN_13
                          |GPIO_PIN_11|GPIO_PIN_10|GPIO_PIN_9|GPIO_PIN_0
                          |GPIO_PIN_8|GPIO_PIN_7|GPIO_PIN_6|GPIO_PIN_1
                          |GPIO_PIN_5|GPIO_PIN_3|GPIO_PIN_4;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF14_LTDC;
  HAL_GPIO_Init(GPIOJ, &GPIO_InitStruct);

  /*Configure GPIO pin : PD3 */
  GPIO_InitStruct.Pin = 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_AF5_SPI2;
  HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);

  /*Configure GPIO pin : PI2 */
  GPIO_InitStruct.Pin = GPIO_PIN_2;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF5_SPI2;
  HAL_GPIO_Init(GPIOI, &GPIO_InitStruct);

  /*Configure GPIO pin : PH15 */
  GPIO_InitStruct.Pin = GPIO_PIN_15;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF3_TIM8;
  HAL_GPIO_Init(GPIOH, &GPIO_InitStruct);

  /*Configure GPIO pins : FDCAN1_RX_Pin FDCAN1_TX_Pin */
  GPIO_InitStruct.Pin = FDCAN1_RX_Pin|FDCAN1_TX_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF9_FDCAN1;
  HAL_GPIO_Init(GPIOH, &GPIO_InitStruct);

  /*Configure GPIO pin : LCD_DISPD7_Pin */
  GPIO_InitStruct.Pin = LCD_DISPD7_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(LCD_DISPD7_GPIO_Port, &GPIO_InitStruct);

  /*Configure GPIO pins : PE5 PE4 */
  GPIO_InitStruct.Pin = GPIO_PIN_5|GPIO_PIN_4;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF10_SAI4;
  HAL_GPIO_Init(GPIOE, &GPIO_InitStruct);

  /*Configure GPIO pins : SDIO1_D5_Pin SDIO1_D4_Pin */
  GPIO_InitStruct.Pin = SDIO1_D5_Pin|SDIO1_D4_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
  GPIO_InitStruct.Alternate = GPIO_AF12_SDIO1;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

  /*Configure GPIO pins : PG15 PG8 PG5 PG4
                           PG0 PG1 */
  GPIO_InitStruct.Pin = GPIO_PIN_15|GPIO_PIN_8|GPIO_PIN_5|GPIO_PIN_4
                          |GPIO_PIN_0|GPIO_PIN_1;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
  GPIO_InitStruct.Alternate = GPIO_AF12_FMC;
  HAL_GPIO_Init(GPIOG, &GPIO_InitStruct);

  /*Configure GPIO pin : SDIO1_CMD_Pin */
  GPIO_InitStruct.Pin = SDIO1_CMD_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
  GPIO_InitStruct.Alternate = GPIO_AF12_SDIO1;
  HAL_GPIO_Init(SDIO1_CMD_GPIO_Port, &GPIO_InitStruct);

  /*Configure GPIO pins : PD0 PD1 PD15 PD14
                           PD10 PD9 PD8 */
  GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_1|GPIO_PIN_15|GPIO_PIN_14
                          |GPIO_PIN_10|GPIO_PIN_9|GPIO_PIN_8;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
  GPIO_InitStruct.Alternate = GPIO_AF12_FMC;
  HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);

  /*Configure GPIO pin : USB_OTG_FS2_ID_Pin */
  GPIO_InitStruct.Pin = USB_OTG_FS2_ID_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(USB_OTG_FS2_ID_GPIO_Port, &GPIO_InitStruct);

  /*Configure GPIO pin : B1_Pin */
  GPIO_InitStruct.Pin = B1_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(B1_GPIO_Port, &GPIO_InitStruct);

  /*Configure GPIO pin : PA8 */
  GPIO_InitStruct.Pin = GPIO_PIN_8;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF1_TIM1;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /*Configure GPIO pins : USB_OTG_FS2_P_Pin USB_OTG_FS2_N_Pin */
  GPIO_InitStruct.Pin = USB_OTG_FS2_P_Pin|USB_OTG_FS2_N_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF10_OTG1_FS;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /*Configure GPIO pins : PF2 PF1 PF0 PF3
                           PF5 PF4 PF13 PF14
                           PF12 PF15 PF11 */
  GPIO_InitStruct.Pin = GPIO_PIN_2|GPIO_PIN_1|GPIO_PIN_0|GPIO_PIN_3
                          |GPIO_PIN_5|GPIO_PIN_4|GPIO_PIN_13|GPIO_PIN_14
                          |GPIO_PIN_12|GPIO_PIN_15|GPIO_PIN_11;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
  GPIO_InitStruct.Alternate = GPIO_AF12_FMC;
  HAL_GPIO_Init(GPIOF, &GPIO_InitStruct);

  /*Configure GPIO pin : LD2_Pin */
  GPIO_InitStruct.Pin = LD2_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(LD2_GPIO_Port, &GPIO_InitStruct);

  /*Configure GPIO pin : LCD_INT_Pin */
  GPIO_InitStruct.Pin = LCD_INT_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_IT_RISING;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(LCD_INT_GPIO_Port, &GPIO_InitStruct);

  /*Configure GPIO pin : LCD_BL_Pin */
  GPIO_InitStruct.Pin = LCD_BL_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(LCD_BL_GPIO_Port, &GPIO_InitStruct);

  /*Configure GPIO pins : PF6 PF7 PF10 */
  GPIO_InitStruct.Pin = GPIO_PIN_6|GPIO_PIN_7|GPIO_PIN_10;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF9_QUADSPI;
  HAL_GPIO_Init(GPIOF, &GPIO_InitStruct);

  /*Configure GPIO pin : PC0 */
  GPIO_InitStruct.Pin = GPIO_PIN_0;
  GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);

  /*Configure GPIO pin : PF9 */
  GPIO_InitStruct.Pin = GPIO_PIN_9;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF10_QUADSPI;
  HAL_GPIO_Init(GPIOF, &GPIO_InitStruct);

  /*Configure GPIO pins : PH5 PH6 PH7 */
  GPIO_InitStruct.Pin = GPIO_PIN_5|GPIO_PIN_6|GPIO_PIN_7;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
  GPIO_InitStruct.Alternate = GPIO_AF12_FMC;
  HAL_GPIO_Init(GPIOH, &GPIO_InitStruct);

  /*Configure GPIO pins : VCP_TX_Pin VCP_RX_Pin */
  GPIO_InitStruct.Pin = VCP_TX_Pin|VCP_RX_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF7_USART3;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

  /*Configure GPIO pin : OTG_FS2_OverCurrent_Pin */
  GPIO_InitStruct.Pin = OTG_FS2_OverCurrent_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_IT_RISING;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  HAL_GPIO_Init(OTG_FS2_OverCurrent_GPIO_Port, &GPIO_InitStruct);

  /*Configure GPIO pin : PA6 */
  GPIO_InitStruct.Pin = GPIO_PIN_6;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF9_TIM13;
  HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /*Configure GPIO pin : PH9 */
  GPIO_InitStruct.Pin = GPIO_PIN_9;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF14_LTDC;
  HAL_GPIO_Init(GPIOH, &GPIO_InitStruct);

  /*Configure GPIO pin : PD11 */
  GPIO_InitStruct.Pin = GPIO_PIN_11;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF9_QUADSPI;
  HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);

  /*Configure GPIO pin : LD1_Pin */
  GPIO_InitStruct.Pin = LD1_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(LD1_GPIO_Port, &GPIO_InitStruct);

  /*Configure GPIO pin : LCD_RST_Pin */
  GPIO_InitStruct.Pin = LCD_RST_Pin;
  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  HAL_GPIO_Init(LCD_RST_GPIO_Port, &GPIO_InitStruct);

  /*Configure GPIO pin : PB15 */
  GPIO_InitStruct.Pin = GPIO_PIN_15;
  GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
  GPIO_InitStruct.Pull = GPIO_NOPULL;
  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.Alternate = GPIO_AF5_SPI2;
  HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

  /*AnalogSwitch Config */
  HAL_SYSCFG_AnalogSwitchConfig(SYSCFG_SWITCH_PA0, SYSCFG_SWITCH_PA0_OPEN);

  /*AnalogSwitch Config */
  HAL_SYSCFG_AnalogSwitchConfig(SYSCFG_SWITCH_PA1, SYSCFG_SWITCH_PA1_OPEN);

}

/* USER CODE BEGIN 4 */

/* USER CODE END 4 */

/* USER CODE BEGIN Header_StartDefaultTask */
/**
  * @brief  Function implementing the defaultTask thread.
  * @PAram  argument: Not used
  * @retval None
  */
/* USER CODE END Header_StartDefaultTask */
void StartDefaultTask(void *argument)
{
  /* USER CODE BEGIN 5 */
  char msg[] = "Working example with UART!\r\n";
  HAL_UART_Transmit(&huart3, (uint8_t*)msg, strlen(msg), HAL_MAX_DELAY);
  
  /* init code for LWIP */
  MX_LWIP_Init();
  
  char initMsg[] = "LwIP initialized successfully\r\n";
  HAL_UART_Transmit(&huart3, (uint8_t*)initMsg, strlen(initMsg), HAL_MAX_DELAY);
  
  /* ETH_CODE: Adding lwiperf to measure TCP/IP performance.
     * iperf 2.0.6 (or older?) is required for the tests. Newer iperf2 versions
     * might work without data check, but they send different headers.
     * iperf3 is not compatible at all.
     * Adding lwiperf.c file to the project is necessary.
     * The default include path should already contain
     * 'lwip/apps/lwiperf.h'
     */
  char iperfMsg[] = "Starting iperf servers...\r\n";
  HAL_UART_Transmit(&huart3, (uint8_t*)iperfMsg, strlen(iperfMsg), HAL_MAX_DELAY);
  
  LOCK_TCPIP_CORE();
  lwiperf_start_tcp_server_default(NULL, NULL);

  ip4_addr_t remote_addr;
  IP4_ADDR(&remote_addr, 192, 168, 1, 1);
  lwiperf_start_tcp_client_default(&remote_addr, NULL, NULL);
  UNLOCK_TCPIP_CORE();
  
  char readyMsg[] = "Network ready - try ping 192.168.1.10\r\n";
  HAL_UART_Transmit(&huart3, (uint8_t*)readyMsg, strlen(readyMsg), HAL_MAX_DELAY);
  
  /* Infinite loop */
  int counter = 0;
  for(;;)
  {
    osDelay(5000);
    char heartbeat[64];
    sprintf(heartbeat, "Heartbeat #%d - system running\r\n", counter++);
    HAL_UART_Transmit(&huart3, (uint8_t*)heartbeat, strlen(heartbeat), HAL_MAX_DELAY);
  }
  /* USER CODE END 5 */
}

/* MPU Configuration */

void MPU_Config(void)
{
  MPU_Region_InitTypeDef MPU_InitStruct = {0};

  /* Disables the MPU */
  HAL_MPU_Disable();

  /** Initializes and configures the Region and the memory to be protected
  */
  MPU_InitStruct.Enable = MPU_REGION_ENABLE;
  MPU_InitStruct.Number = MPU_REGION_NUMBER0;
  MPU_InitStruct.BaseAddress = 0x0;
  MPU_InitStruct.Size = MPU_REGION_SIZE_4GB;
  MPU_InitStruct.SubRegionDisable = 0x87;
  MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL0;
  MPU_InitStruct.AccessPermission = MPU_REGION_NO_ACCESS;
  MPU_InitStruct.DisableExec = MPU_INSTRUCTION_ACCESS_DISABLE;
  MPU_InitStruct.IsShareable = MPU_ACCESS_SHAREABLE;
  MPU_InitStruct.IsCacheable = MPU_ACCESS_NOT_CACHEABLE;
  MPU_InitStruct.IsBufferable = MPU_ACCESS_NOT_BUFFERABLE;

  HAL_MPU_ConfigRegion(&MPU_InitStruct);

  /** Initializes and configures the Region and the memory to be protected
  */
  MPU_InitStruct.Number = MPU_REGION_NUMBER1;
  MPU_InitStruct.BaseAddress = 0x30020000;
  MPU_InitStruct.Size = MPU_REGION_SIZE_128KB;
  MPU_InitStruct.SubRegionDisable = 0x0;
  MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL1;
  MPU_InitStruct.AccessPermission = MPU_REGION_FULL_ACCESS;
  MPU_InitStruct.IsShareable = MPU_ACCESS_NOT_SHAREABLE;

  HAL_MPU_ConfigRegion(&MPU_InitStruct);

  /** Initializes and configures the Region and the memory to be protected
  */
  MPU_InitStruct.Number = MPU_REGION_NUMBER2;
  MPU_InitStruct.BaseAddress = 0x30040000;
  MPU_InitStruct.Size = MPU_REGION_SIZE_512B;
  MPU_InitStruct.TypeExtField = MPU_TEX_LEVEL0;
  MPU_InitStruct.IsShareable = MPU_ACCESS_SHAREABLE;
  MPU_InitStruct.IsBufferable = MPU_ACCESS_BUFFERABLE;

  HAL_MPU_ConfigRegion(&MPU_InitStruct);
  /* Enables the MPU */
  HAL_MPU_Enable(MPU_PRIVILEGED_DEFAULT);

}

/**
  * @brief  Period elapsed callback in non blocking mode
  * @note   This function is called  when TIM6 interrupt took place, inside
  * HAL_TIM_IRQHandler(). It makes a direct call to HAL_IncTick() to increment
  * a global variable "uwTick" used as application time base.
  * @PAram  htim : TIM handle
  * @retval None
  */
void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{
  /* USER CODE BEGIN Callback 0 */

  /* USER CODE END Callback 0 */
  if (htim->Instance == TIM6) {
    HAL_IncTick();
  }
  /* USER CODE BEGIN Callback 1 */

  /* USER CODE END Callback 1 */
}

/**
  * @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.
  * @PAram  file: pointer to the source file name
  * @PAram  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 */

Pavel A. · ‎2026-03-05

> I am trying to communicate with UART3 to Tera Team, will you help verify please:

It looks OK. USART3, should be on pins PB10, PB11. Anything does not work?

ksale.1 · ‎2026-03-06

AT LAST PINGING: Request timed out.
Request timed out.
Reply from 192.168.1.10: bytes=32 time<1ms TTL=255
Reply from 192.168.1.10: bytes=32 time<1ms TTL=255
Reply from 192.168.1.10: bytes=32 time<1ms TTL=255
Reply from 192.168.1.10: bytes=32 time<1ms TTL=255
Reply from 192.168.1.10: bytes=32 time<1ms TTL=255
Reply from 192.168.1.10: bytes=32 time<1ms TTL=255
Reply from 192.168.1.10: bytes=32 time<1ms TTL=255
Reply from 192.168.1.10: bytes=32 time<1ms TTL=255
Reply from 192.168.1.10: bytes=32 time<1ms TTL=255

Ping statistics for 192.168.1.10:
Packets: Sent = 52, Received = 9, Lost = 43 (82% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0ms
Control-C
^C
C:\Windows\System32>