Why I need to add delay after HAL_UART_Transmit_DMA and before memset at IRQ call back function
void vcom_IRQHandler(void) // external interrupt for USART2_IRQHandler { HAL_UART_IRQHandler(&UartHandle); USER_UART_IRQHandler(&UartHandle); } void USER_UART_IRQHandler(UART_HandleTypeDef *huart) { if(USART2 == ...