#include #include #include #include "usart.h" #include "systick.h" void usart_init(int baudrate) { GPIO_InitTypeDef GPIO_InitStructure; USART_InitTypeDef USART_InitStructure; /* enable peripheral clock for USART3 */ RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART3, ENABLE); /* GPIOD clock enable */ RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOD, ENABLE); /* GPIOA Configuration: USART3 TX on PD8/9 */ GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8|GPIO_Pin_9; GPIO_Init(GPIOD, &GPIO_InitStructure); /* Connect USART3 pins to AF2 */ GPIO_PinAFConfig(GPIOD, GPIO_PinSource8, GPIO_AF_USART3); GPIO_PinAFConfig(GPIOD, GPIO_PinSource9, GPIO_AF_USART3); /* Disable USART */ USART_Cmd(USART3, DISABLE); systick_sleep(10); USART_DeInit(USART3); systick_sleep(10); USART_InitStructure.USART_BaudRate = baudrate; USART_InitStructure.USART_WordLength = USART_WordLength_8b; USART_InitStructure.USART_StopBits = USART_StopBits_1; USART_InitStructure.USART_Parity = USART_Parity_No; USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None; USART_InitStructure.USART_Mode = USART_Mode_Tx|USART_Mode_Rx; USART_Init(USART3, &USART_InitStructure); USART_Cmd(USART3, ENABLE); // enable USART3 } void usart_set_baudrate(int baudrate) { USART_InitTypeDef USART_InitStructure; USART_InitStructure.USART_BaudRate = baudrate; USART_InitStructure.USART_WordLength = USART_WordLength_8b; USART_InitStructure.USART_StopBits = USART_StopBits_1; USART_InitStructure.USART_Parity = USART_Parity_No; USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None; USART_InitStructure.USART_Mode = USART_Mode_Tx|USART_Mode_Rx; USART_Init(USART3, &USART_InitStructure); USART_Cmd(USART3, ENABLE); // enable USART3 } void usart_send(uint8_t byte) { USART_SendData(USART3, byte); while (!USART_GetFlagStatus(USART3, USART_FLAG_TXE)); } uint8_t usart_recv() { return USART_ReceiveData(USART3); }