2025-01-11 10:49 AM - last edited on 2025-01-11 10:53 AM by Andrew Neil
Hi,
I was working with Modbus Protocol with the external device(Aster TDS Meter).
The Modbus External device Settings in 9600baud rate, 8bit,parity none and 1stop bit
My Problem was when i connect the device with UART4 i am able to get the output properly but i need to use UART2 but while using UART2 not able to receive the data properly what i am missing?
UART4 Configuration
static void MX_USART4_UART_Init(void)
{
/* USER CODE BEGIN USART4_Init 0 */
/* USER CODE END USART4_Init 0 */
/* USER CODE BEGIN USART4_Init 1 */
/* USER CODE END USART4_Init 1 */
huart4.Instance = USART4;
huart4.Init.BaudRate = 9600;
huart4.Init.WordLength = UART_WORDLENGTH_8B;
huart4.Init.StopBits = UART_STOPBITS_1;
huart4.Init.Parity = UART_PARITY_NONE;
huart4.Init.Mode = UART_MODE_TX_RX;
huart4.Init.HwFlowCtl = UART_HWCONTROL_NONE;
huart4.Init.OverSampling = UART_OVERSAMPLING_16;
huart4.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;
huart4.Init.ClockPrescaler = UART_PRESCALER_DIV1;
huart4.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;
if (HAL_UART_Init(&huart4) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN USART4_Init 2 */
/* USER CODE END USART4_Init 2 */
}
UART 4 Connected with External device(Aster) with RS485 Module Working Fine....!
UART 2 Configuration:
static void MX_USART2_UART_Init(void)
{
/* USER CODE BEGIN USART2_Init 0 */
/* USER CODE END USART2_Init 0 */
/* USER CODE BEGIN USART2_Init 1 */
/* USER CODE END USART2_Init 1 */
huart2.Instance = USART2;
huart2.Init.BaudRate = 9600;
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_8_8) != HAL_OK)
{
Error_Handler();
}
if (HAL_UARTEx_SetRxFifoThreshold(&huart2, UART_RXFIFO_THRESHOLD_8_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 */
}
But In UART 2 Connected with External Device(Aster)Via RS485 module not working or not able to receive the data
So what makes the difference between UART2 and UART4
Expect the Configuration all other TX buffers RX buffers are same tested in both UART4 working fine but UART 2 not working!
Please explain where i am doing wrong!
Advance Thanks!
A.Mathew