stm32串口1重映射

### STM32 UART Pin Remapping In STM32 microcontrollers, the Alternate Function (AF) remapping feature allows changing the default pins used by peripherals such as UART to alternative ones. This flexibility is particularly useful when designing PCB layouts or avoiding conflicts with other functionalities. To perform UART pin remapping on an STM32 device: The `RCC_APB2PeriphClockCmd` function enables the peripheral clock for GPIO and AFIO modules which are necessary before configuring any alternate functions[^1]. For newer HAL libraries, this step might be handled internally within initialization routines but remains crucial knowledge. For actual pin remapping of UART signals, specific bits inside the `AFIO_MAPR` register must be configured appropriately depending upon the desired UART instance and target pins. Each UART has predefined sets of possible alternate locations that can serve its TX/RX lines; these options vary between different STM32 families and models[^2]. Here's a code snippet demonstrating how one could enable USART1_TX & RX remap using standard peripheral library syntax: ```c // Enable clocks for required peripherals RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE); // Configure AFIO MAPR Register according to your needs. GPIO_PinRemapConfig(GPIO_Remap_USART1, ENABLE); ``` Additionally, after setting up hardware configuration through registers like above, proper initialization structures should also set corresponding parameters indicating usage of alternate functions via their respective fields in structure members related to mode settings during setup phase[^3].

### STM32 UART Remapping Configuration and Implementation In STM32 microcontrollers, UART pin remapping can be achieved through configuring the Alternate Function I/O (AFIO) peripheral. This allows for flexibility in choosing which pins will serve as TX/RX lines for UART communication. For implementing UART remapping on an STM32 device: The AFIO_MAPR register controls alternate function remappings including those for various peripherals like USARTs. To perform a remap operation specifically for USART1 or other USART instances, one must set specific bits within this register according to the desired new location of the UART signals[^1]. Here's how to configure it using standard peripheral library functions provided with STM32 firmware libraries: ```c // Example code snippet showing how to do GPIO and USART initialization along with remapping. GPIO_InitTypeDef GPIO_InitStruct; USART_InitTypeDef USART_InitStruct; /* Enable clocks */ RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE); RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE); /* Configure USART1_TX and USART1_RX as alternate function push-pull */ GPIO_InitStruct.GPIO_Pin = GPIO_Pin_9; // Original TX Pin PA9 GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz; GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF_PP; GPIO_Init(GPIOA, &GPIO_InitStruct); GPIO_InitStruct.GPIO_Pin = GPIO_Pin_10; // Original RX Pin PA10 GPIO_InitStruct.GPIO_Mode = GPIO_Mode_IN_FLOATING; GPIO_Init(GPIOA, &GPIO_InitStruct); // Perform partial remap if necessary based on your target board layout if (needRemap){ GPIO_PinRemapConfig(GPIO_PartialRemap_USART1, ENABLE); } /* Initialize USART settings */ USART_InitStruct.USART_BaudRate = 9600; USART_InitStruct.USART_WordLength = USART_WordLength_8b; USART_InitStruct.USART_StopBits = USART_StopBits_1; USART_InitStruct.USART_Parity = USART_Parity_No ; USART_InitStruct.USART_HardwareFlowControl = USART_HardwareFlowControl_None; USART_InitStruct.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; USART_Init(USART1, &USART_InitStruct); /* Enable USART */ USART_Cmd(USART1, ENABLE); ``` This example demonstrates setting up USART1 but similar principles apply when working with different USART modules available on the chip. The actual configuration may vary depending upon whether full or partial remaps are supported by hardware design and what alternative locations you wish to use instead of default ones specified during initial setup stages.